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-rw-r--r--drivers/hwtracing/coresight/coresight-etm3x.c107
-rw-r--r--drivers/hwtracing/coresight/coresight-etm4x.c22
-rw-r--r--drivers/hwtracing/coresight/coresight.c5
-rw-r--r--drivers/hwtracing/intel_th/Kconfig72
-rw-r--r--drivers/hwtracing/intel_th/Makefile18
-rw-r--r--drivers/hwtracing/intel_th/core.c692
-rw-r--r--drivers/hwtracing/intel_th/debug.c36
-rw-r--r--drivers/hwtracing/intel_th/debug.h34
-rw-r--r--drivers/hwtracing/intel_th/gth.c706
-rw-r--r--drivers/hwtracing/intel_th/gth.h66
-rw-r--r--drivers/hwtracing/intel_th/intel_th.h244
-rw-r--r--drivers/hwtracing/intel_th/msu.c1509
-rw-r--r--drivers/hwtracing/intel_th/msu.h116
-rw-r--r--drivers/hwtracing/intel_th/pci.c86
-rw-r--r--drivers/hwtracing/intel_th/pti.c252
-rw-r--r--drivers/hwtracing/intel_th/pti.h29
-rw-r--r--drivers/hwtracing/intel_th/sth.c259
-rw-r--r--drivers/hwtracing/intel_th/sth.h42
-rw-r--r--drivers/hwtracing/stm/Kconfig26
-rw-r--r--drivers/hwtracing/stm/Makefile9
-rw-r--r--drivers/hwtracing/stm/console.c80
-rw-r--r--drivers/hwtracing/stm/core.c1032
-rw-r--r--drivers/hwtracing/stm/dummy_stm.c66
-rw-r--r--drivers/hwtracing/stm/policy.c529
-rw-r--r--drivers/hwtracing/stm/stm.h87
25 files changed, 6073 insertions, 51 deletions
diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x.c
index bf2476ed9356..d630b7ece735 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x.c
@@ -191,7 +191,8 @@ static void etm_set_prog(struct etm_drvdata *drvdata)
isb();
if (coresight_timeout_etm(drvdata, ETMSR, ETMSR_PROG_BIT, 1)) {
dev_err(drvdata->dev,
- "timeout observed when probing at offset %#x\n", ETMSR);
+ "%s: timeout observed when probing at offset %#x\n",
+ __func__, ETMSR);
}
}
@@ -209,7 +210,8 @@ static void etm_clr_prog(struct etm_drvdata *drvdata)
isb();
if (coresight_timeout_etm(drvdata, ETMSR, ETMSR_PROG_BIT, 0)) {
dev_err(drvdata->dev,
- "timeout observed when probing at offset %#x\n", ETMSR);
+ "%s: timeout observed when probing at offset %#x\n",
+ __func__, ETMSR);
}
}
@@ -313,14 +315,6 @@ static void etm_enable_hw(void *info)
dev_dbg(drvdata->dev, "cpu: %d enable smp call done\n", drvdata->cpu);
}
-static int etm_trace_id_simple(struct etm_drvdata *drvdata)
-{
- if (!drvdata->enable)
- return drvdata->traceid;
-
- return (etm_readl(drvdata, ETMTRACEIDR) & ETM_TRACEID_MASK);
-}
-
static int etm_trace_id(struct coresight_device *csdev)
{
struct etm_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -1506,44 +1500,17 @@ static ssize_t timestamp_event_store(struct device *dev,
}
static DEVICE_ATTR_RW(timestamp_event);
-static ssize_t status_show(struct device *dev,
- struct device_attribute *attr, char *buf)
+static ssize_t cpu_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
{
- int ret;
- unsigned long flags;
+ int val;
struct etm_drvdata *drvdata = dev_get_drvdata(dev->parent);
- pm_runtime_get_sync(drvdata->dev);
- spin_lock_irqsave(&drvdata->spinlock, flags);
-
- CS_UNLOCK(drvdata->base);
- ret = sprintf(buf,
- "ETMCCR: 0x%08x\n"
- "ETMCCER: 0x%08x\n"
- "ETMSCR: 0x%08x\n"
- "ETMIDR: 0x%08x\n"
- "ETMCR: 0x%08x\n"
- "ETMTRACEIDR: 0x%08x\n"
- "Enable event: 0x%08x\n"
- "Enable start/stop: 0x%08x\n"
- "Enable control: CR1 0x%08x CR2 0x%08x\n"
- "CPU affinity: %d\n",
- drvdata->etmccr, drvdata->etmccer,
- etm_readl(drvdata, ETMSCR), etm_readl(drvdata, ETMIDR),
- etm_readl(drvdata, ETMCR), etm_trace_id_simple(drvdata),
- etm_readl(drvdata, ETMTEEVR),
- etm_readl(drvdata, ETMTSSCR),
- etm_readl(drvdata, ETMTECR1),
- etm_readl(drvdata, ETMTECR2),
- drvdata->cpu);
- CS_LOCK(drvdata->base);
-
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- pm_runtime_put(drvdata->dev);
+ val = drvdata->cpu;
+ return scnprintf(buf, PAGE_SIZE, "%d\n", val);
- return ret;
}
-static DEVICE_ATTR_RO(status);
+static DEVICE_ATTR_RO(cpu);
static ssize_t traceid_show(struct device *dev,
struct device_attribute *attr, char *buf)
@@ -1619,11 +1586,61 @@ static struct attribute *coresight_etm_attrs[] = {
&dev_attr_ctxid_mask.attr,
&dev_attr_sync_freq.attr,
&dev_attr_timestamp_event.attr,
- &dev_attr_status.attr,
&dev_attr_traceid.attr,
+ &dev_attr_cpu.attr,
+ NULL,
+};
+
+#define coresight_simple_func(name, offset) \
+static ssize_t name##_show(struct device *_dev, \
+ struct device_attribute *attr, char *buf) \
+{ \
+ struct etm_drvdata *drvdata = dev_get_drvdata(_dev->parent); \
+ return scnprintf(buf, PAGE_SIZE, "0x%x\n", \
+ readl_relaxed(drvdata->base + offset)); \
+} \
+DEVICE_ATTR_RO(name)
+
+coresight_simple_func(etmccr, ETMCCR);
+coresight_simple_func(etmccer, ETMCCER);
+coresight_simple_func(etmscr, ETMSCR);
+coresight_simple_func(etmidr, ETMIDR);
+coresight_simple_func(etmcr, ETMCR);
+coresight_simple_func(etmtraceidr, ETMTRACEIDR);
+coresight_simple_func(etmteevr, ETMTEEVR);
+coresight_simple_func(etmtssvr, ETMTSSCR);
+coresight_simple_func(etmtecr1, ETMTECR1);
+coresight_simple_func(etmtecr2, ETMTECR2);
+
+static struct attribute *coresight_etm_mgmt_attrs[] = {
+ &dev_attr_etmccr.attr,
+ &dev_attr_etmccer.attr,
+ &dev_attr_etmscr.attr,
+ &dev_attr_etmidr.attr,
+ &dev_attr_etmcr.attr,
+ &dev_attr_etmtraceidr.attr,
+ &dev_attr_etmteevr.attr,
+ &dev_attr_etmtssvr.attr,
+ &dev_attr_etmtecr1.attr,
+ &dev_attr_etmtecr2.attr,
+ NULL,
+};
+
+static const struct attribute_group coresight_etm_group = {
+ .attrs = coresight_etm_attrs,
+};
+
+
+static const struct attribute_group coresight_etm_mgmt_group = {
+ .attrs = coresight_etm_mgmt_attrs,
+ .name = "mgmt",
+};
+
+static const struct attribute_group *coresight_etm_groups[] = {
+ &coresight_etm_group,
+ &coresight_etm_mgmt_group,
NULL,
};
-ATTRIBUTE_GROUPS(coresight_etm);
static int etm_cpu_callback(struct notifier_block *nfb, unsigned long action,
void *hcpu)
diff --git a/drivers/hwtracing/coresight/coresight-etm4x.c b/drivers/hwtracing/coresight/coresight-etm4x.c
index 254a81a4e6f4..a6707642bb23 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x.c
@@ -136,7 +136,9 @@ static void etm4_enable_hw(void *info)
writel_relaxed(drvdata->cntr_val[i],
drvdata->base + TRCCNTVRn(i));
}
- for (i = 0; i < drvdata->nr_resource; i++)
+
+ /* Resource selector pair 0 is always implemented and reserved */
+ for (i = 2; i < drvdata->nr_resource * 2; i++)
writel_relaxed(drvdata->res_ctrl[i],
drvdata->base + TRCRSCTLRn(i));
@@ -489,8 +491,9 @@ static ssize_t reset_store(struct device *dev,
drvdata->cntr_val[i] = 0x0;
}
- drvdata->res_idx = 0x0;
- for (i = 0; i < drvdata->nr_resource; i++)
+ /* Resource selector pair 0 is always implemented and reserved */
+ drvdata->res_idx = 0x2;
+ for (i = 2; i < drvdata->nr_resource * 2; i++)
drvdata->res_ctrl[i] = 0x0;
for (i = 0; i < drvdata->nr_ss_cmp; i++) {
@@ -1732,7 +1735,7 @@ static ssize_t res_idx_store(struct device *dev,
if (kstrtoul(buf, 16, &val))
return -EINVAL;
/* Resource selector pair 0 is always implemented and reserved */
- if ((val == 0) || (val >= drvdata->nr_resource))
+ if (val < 2 || val >= drvdata->nr_resource * 2)
return -EINVAL;
/*
@@ -2416,8 +2419,13 @@ static void etm4_init_arch_data(void *info)
drvdata->nr_addr_cmp = BMVAL(etmidr4, 0, 3);
/* NUMPC, bits[15:12] number of PE comparator inputs for tracing */
drvdata->nr_pe_cmp = BMVAL(etmidr4, 12, 15);
- /* NUMRSPAIR, bits[19:16] the number of resource pairs for tracing */
- drvdata->nr_resource = BMVAL(etmidr4, 16, 19);
+ /*
+ * NUMRSPAIR, bits[19:16]
+ * The number of resource pairs conveyed by the HW starts at 0, i.e a
+ * value of 0x0 indicate 1 resource pair, 0x1 indicate two and so on.
+ * As such add 1 to the value of NUMRSPAIR for a better representation.
+ */
+ drvdata->nr_resource = BMVAL(etmidr4, 16, 19) + 1;
/*
* NUMSSCC, bits[23:20] the number of single-shot
* comparator control for tracing
@@ -2504,6 +2512,8 @@ static void etm4_init_default_data(struct etmv4_drvdata *drvdata)
drvdata->cntr_val[i] = 0x0;
}
+ /* Resource selector pair 0 is always implemented and reserved */
+ drvdata->res_idx = 0x2;
for (i = 2; i < drvdata->nr_resource * 2; i++)
drvdata->res_ctrl[i] = 0x0;
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index 894531d315b8..e25492137d8b 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -240,6 +240,11 @@ static int coresight_enable_path(struct list_head *path)
int ret = 0;
struct coresight_device *cd;
+ /*
+ * At this point we have a full @path, from source to sink. The
+ * sink is the first entry and the source the last one. Go through
+ * all the components and enable them one by one.
+ */
list_for_each_entry(cd, path, path_link) {
if (cd == list_first_entry(path, struct coresight_device,
path_link)) {
diff --git a/drivers/hwtracing/intel_th/Kconfig b/drivers/hwtracing/intel_th/Kconfig
new file mode 100644
index 000000000000..b7a9073d968b
--- /dev/null
+++ b/drivers/hwtracing/intel_th/Kconfig
@@ -0,0 +1,72 @@
+config INTEL_TH
+ tristate "Intel(R) Trace Hub controller"
+ help
+ Intel(R) Trace Hub (TH) is a set of hardware blocks (subdevices) that
+ produce, switch and output trace data from multiple hardware and
+ software sources over several types of trace output ports encoded
+ in System Trace Protocol (MIPI STPv2) and is intended to perform
+ full system debugging.
+
+ This option enables intel_th bus and common code used by TH
+ subdevices to interact with each other and hardware and for
+ platform glue layers to drive Intel TH devices.
+
+ Say Y here to enable Intel(R) Trace Hub controller support.
+
+if INTEL_TH
+
+config INTEL_TH_PCI
+ tristate "Intel(R) Trace Hub PCI controller"
+ depends on PCI
+ help
+ Intel(R) Trace Hub may exist as a PCI device. This option enables
+ support glue layer for PCI-based Intel TH.
+
+ Say Y here to enable PCI Intel TH support.
+
+config INTEL_TH_GTH
+ tristate "Intel(R) Trace Hub Global Trace Hub"
+ help
+ Global Trace Hub (GTH) is the central component of the
+ Intel TH infrastructure and acts as a switch for source
+ and output devices. This driver is required for other
+ Intel TH subdevices to initialize.
+
+ Say Y here to enable GTH subdevice of Intel(R) Trace Hub.
+
+config INTEL_TH_STH
+ tristate "Intel(R) Trace Hub Software Trace Hub support"
+ depends on STM
+ help
+ Software Trace Hub (STH) enables trace data from software
+ trace sources to be sent out via Intel(R) Trace Hub. It
+ uses stm class device to interface with its sources.
+
+ Say Y here to enable STH subdevice of Intel(R) Trace Hub.
+
+config INTEL_TH_MSU
+ tristate "Intel(R) Trace Hub Memory Storage Unit"
+ help
+ Memory Storage Unit (MSU) trace output device enables
+ storing STP traces to system memory. It supports single
+ and multiblock modes of operation and provides read()
+ and mmap() access to the collected data.
+
+ Say Y here to enable MSU output device for Intel TH.
+
+config INTEL_TH_PTI
+ tristate "Intel(R) Trace Hub PTI output"
+ help
+ Parallel Trace Interface unit (PTI) is a trace output device
+ of Intel TH architecture that facilitates STP trace output via
+ a PTI port.
+
+ Say Y to enable PTI output of Intel TH data.
+
+config INTEL_TH_DEBUG
+ bool "Intel(R) Trace Hub debugging"
+ depends on DEBUG_FS
+ help
+ Say Y here to enable debugging.
+
+endif
diff --git a/drivers/hwtracing/intel_th/Makefile b/drivers/hwtracing/intel_th/Makefile
new file mode 100644
index 000000000000..81d42fe918f7
--- /dev/null
+++ b/drivers/hwtracing/intel_th/Makefile
@@ -0,0 +1,18 @@
+obj-$(CONFIG_INTEL_TH) += intel_th.o
+intel_th-y := core.o
+intel_th-$(CONFIG_INTEL_TH_DEBUG) += debug.o
+
+obj-$(CONFIG_INTEL_TH_PCI) += intel_th_pci.o
+intel_th_pci-y := pci.o
+
+obj-$(CONFIG_INTEL_TH_GTH) += intel_th_gth.o
+intel_th_gth-y := gth.o
+
+obj-$(CONFIG_INTEL_TH_STH) += intel_th_sth.o
+intel_th_sth-y := sth.o
+
+obj-$(CONFIG_INTEL_TH_MSU) += intel_th_msu.o
+intel_th_msu-y := msu.o
+
+obj-$(CONFIG_INTEL_TH_PTI) += intel_th_pti.o
+intel_th_pti-y := pti.o
diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c
new file mode 100644
index 000000000000..165d3001c301
--- /dev/null
+++ b/drivers/hwtracing/intel_th/core.c
@@ -0,0 +1,692 @@
+/*
+ * Intel(R) Trace Hub driver core
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/sysfs.h>
+#include <linux/kdev_t.h>
+#include <linux/debugfs.h>
+#include <linux/idr.h>
+#include <linux/pci.h>
+#include <linux/dma-mapping.h>
+
+#include "intel_th.h"
+#include "debug.h"
+
+static DEFINE_IDA(intel_th_ida);
+
+static int intel_th_match(struct device *dev, struct device_driver *driver)
+{
+ struct intel_th_driver *thdrv = to_intel_th_driver(driver);
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+
+ if (thdev->type == INTEL_TH_SWITCH &&
+ (!thdrv->enable || !thdrv->disable))
+ return 0;
+
+ return !strcmp(thdev->name, driver->name);
+}
+
+static int intel_th_child_remove(struct device *dev, void *data)
+{
+ device_release_driver(dev);
+
+ return 0;
+}
+
+static int intel_th_probe(struct device *dev)
+{
+ struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+ struct intel_th_driver *hubdrv;
+ struct intel_th_device *hub = NULL;
+ int ret;
+
+ if (thdev->type == INTEL_TH_SWITCH)
+ hub = thdev;
+ else if (dev->parent)
+ hub = to_intel_th_device(dev->parent);
+
+ if (!hub || !hub->dev.driver)
+ return -EPROBE_DEFER;
+
+ hubdrv = to_intel_th_driver(hub->dev.driver);
+
+ ret = thdrv->probe(to_intel_th_device(dev));
+ if (ret)
+ return ret;
+
+ if (thdev->type == INTEL_TH_OUTPUT &&
+ !intel_th_output_assigned(thdev))
+ ret = hubdrv->assign(hub, thdev);
+
+ return ret;
+}
+
+static int intel_th_remove(struct device *dev)
+{
+ struct intel_th_driver *thdrv = to_intel_th_driver(dev->driver);
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+ struct intel_th_device *hub = to_intel_th_device(dev->parent);
+ int err;
+
+ if (thdev->type == INTEL_TH_SWITCH) {
+ err = device_for_each_child(dev, thdev, intel_th_child_remove);
+ if (err)
+ return err;
+ }
+
+ thdrv->remove(thdev);
+
+ if (intel_th_output_assigned(thdev)) {
+ struct intel_th_driver *hubdrv =
+ to_intel_th_driver(dev->parent->driver);
+
+ if (hub->dev.driver)
+ hubdrv->unassign(hub, thdev);
+ }
+
+ return 0;
+}
+
+static struct bus_type intel_th_bus = {
+ .name = "intel_th",
+ .dev_attrs = NULL,
+ .match = intel_th_match,
+ .probe = intel_th_probe,
+ .remove = intel_th_remove,
+};
+
+static void intel_th_device_free(struct intel_th_device *thdev);
+
+static void intel_th_device_release(struct device *dev)
+{
+ intel_th_device_free(to_intel_th_device(dev));
+}
+
+static struct device_type intel_th_source_device_type = {
+ .name = "intel_th_source_device",
+ .release = intel_th_device_release,
+};
+
+static char *intel_th_output_devnode(struct device *dev, umode_t *mode,
+ kuid_t *uid, kgid_t *gid)
+{
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+ char *node;
+
+ if (thdev->id >= 0)
+ node = kasprintf(GFP_KERNEL, "intel_th%d/%s%d", 0, thdev->name,
+ thdev->id);
+ else
+ node = kasprintf(GFP_KERNEL, "intel_th%d/%s", 0, thdev->name);
+
+ return node;
+}
+
+static ssize_t port_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+
+ if (thdev->output.port >= 0)
+ return scnprintf(buf, PAGE_SIZE, "%u\n", thdev->output.port);
+
+ return scnprintf(buf, PAGE_SIZE, "unassigned\n");
+}
+
+static DEVICE_ATTR_RO(port);
+
+static int intel_th_output_activate(struct intel_th_device *thdev)
+{
+ struct intel_th_driver *thdrv = to_intel_th_driver(thdev->dev.driver);
+
+ if (thdrv->activate)
+ return thdrv->activate(thdev);
+
+ intel_th_trace_enable(thdev);
+
+ return 0;
+}
+
+static void intel_th_output_deactivate(struct intel_th_device *thdev)
+{
+ struct intel_th_driver *thdrv = to_intel_th_driver(thdev->dev.driver);
+
+ if (thdrv->deactivate)
+ thdrv->deactivate(thdev);
+ else
+ intel_th_trace_disable(thdev);
+}
+
+static ssize_t active_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", thdev->output.active);
+}
+
+static ssize_t active_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct intel_th_device *thdev = to_intel_th_device(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ if (!!val != thdev->output.active) {
+ if (val)
+ ret = intel_th_output_activate(thdev);
+ else
+ intel_th_output_deactivate(thdev);
+ }
+
+ return ret ? ret : size;
+}
+
+static DEVICE_ATTR_RW(active);
+
+static struct attribute *intel_th_output_attrs[] = {
+ &dev_attr_port.attr,
+ &dev_attr_active.attr,
+ NULL,
+};
+
+ATTRIBUTE_GROUPS(intel_th_output);
+
+static struct device_type intel_th_output_device_type = {
+ .name = "intel_th_output_device",
+ .groups = intel_th_output_groups,
+ .release = intel_th_device_release,
+ .devnode = intel_th_output_devnode,
+};
+
+static struct device_type intel_th_switch_device_type = {
+ .name = "intel_th_switch_device",
+ .release = intel_th_device_release,
+};
+
+static struct device_type *intel_th_device_type[] = {
+ [INTEL_TH_SOURCE] = &intel_th_source_device_type,
+ [INTEL_TH_OUTPUT] = &intel_th_output_device_type,
+ [INTEL_TH_SWITCH] = &intel_th_switch_device_type,
+};
+
+int intel_th_driver_register(struct intel_th_driver *thdrv)
+{
+ if (!thdrv->probe || !thdrv->remove)
+ return -EINVAL;
+
+ thdrv->driver.bus = &intel_th_bus;
+
+ return driver_register(&thdrv->driver);
+}
+EXPORT_SYMBOL_GPL(intel_th_driver_register);
+
+void intel_th_driver_unregister(struct intel_th_driver *thdrv)
+{
+ driver_unregister(&thdrv->driver);
+}
+EXPORT_SYMBOL_GPL(intel_th_driver_unregister);
+
+static struct intel_th_device *
+intel_th_device_alloc(struct intel_th *th, unsigned int type, const char *name,
+ int id)
+{
+ struct device *parent;
+ struct intel_th_device *thdev;
+
+ if (type == INTEL_TH_SWITCH)
+ parent = th->dev;
+ else
+ parent = &th->hub->dev;
+
+ thdev = kzalloc(sizeof(*thdev) + strlen(name) + 1, GFP_KERNEL);
+ if (!thdev)
+ return NULL;
+
+ thdev->id = id;
+ thdev->type = type;
+
+ strcpy(thdev->name, name);
+ device_initialize(&thdev->dev);
+ thdev->dev.bus = &intel_th_bus;
+ thdev->dev.type = intel_th_device_type[type];
+ thdev->dev.parent = parent;
+ thdev->dev.dma_mask = parent->dma_mask;
+ thdev->dev.dma_parms = parent->dma_parms;
+ dma_set_coherent_mask(&thdev->dev, parent->coherent_dma_mask);
+ if (id >= 0)
+ dev_set_name(&thdev->dev, "%d-%s%d", th->id, name, id);
+ else
+ dev_set_name(&thdev->dev, "%d-%s", th->id, name);
+
+ return thdev;
+}
+
+static int intel_th_device_add_resources(struct intel_th_device *thdev,
+ struct resource *res, int nres)
+{
+ struct resource *r;
+
+ r = kmemdup(res, sizeof(*res) * nres, GFP_KERNEL);
+ if (!r)
+ return -ENOMEM;
+
+ thdev->resource = r;
+ thdev->num_resources = nres;
+
+ return 0;
+}
+
+static void intel_th_device_remove(struct intel_th_device *thdev)
+{
+ device_del(&thdev->dev);
+ put_device(&thdev->dev);
+}
+
+static void intel_th_device_free(struct intel_th_device *thdev)
+{
+ kfree(thdev->resource);
+ kfree(thdev);
+}
+
+/*
+ * Intel(R) Trace Hub subdevices
+ */
+static struct intel_th_subdevice {
+ const char *name;
+ struct resource res[3];
+ unsigned nres;
+ unsigned type;
+ unsigned otype;
+ int id;
+} intel_th_subdevices[TH_SUBDEVICE_MAX] = {
+ {
+ .nres = 1,
+ .res = {
+ {
+ .start = REG_GTH_OFFSET,
+ .end = REG_GTH_OFFSET + REG_GTH_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ },
+ .name = "gth",
+ .type = INTEL_TH_SWITCH,
+ .id = -1,
+ },
+ {
+ .nres = 2,
+ .res = {
+ {
+ .start = REG_MSU_OFFSET,
+ .end = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
+ .start = BUF_MSU_OFFSET,
+ .end = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ },
+ .name = "msc",
+ .id = 0,
+ .type = INTEL_TH_OUTPUT,
+ .otype = GTH_MSU,
+ },
+ {
+ .nres = 2,
+ .res = {
+ {
+ .start = REG_MSU_OFFSET,
+ .end = REG_MSU_OFFSET + REG_MSU_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
+ .start = BUF_MSU_OFFSET,
+ .end = BUF_MSU_OFFSET + BUF_MSU_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ },
+ .name = "msc",
+ .id = 1,
+ .type = INTEL_TH_OUTPUT,
+ .otype = GTH_MSU,
+ },
+ {
+ .nres = 2,
+ .res = {
+ {
+ .start = REG_STH_OFFSET,
+ .end = REG_STH_OFFSET + REG_STH_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ {
+ .start = TH_MMIO_SW,
+ .end = 0,
+ .flags = IORESOURCE_MEM,
+ },
+ },
+ .id = -1,
+ .name = "sth",
+ .type = INTEL_TH_SOURCE,
+ },
+ {
+ .nres = 1,
+ .res = {
+ {
+ .start = REG_PTI_OFFSET,
+ .end = REG_PTI_OFFSET + REG_PTI_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ },
+ .id = -1,
+ .name = "pti",
+ .type = INTEL_TH_OUTPUT,
+ .otype = GTH_PTI,
+ },
+ {
+ .nres = 1,
+ .res = {
+ {
+ .start = REG_DCIH_OFFSET,
+ .end = REG_DCIH_OFFSET + REG_DCIH_LENGTH - 1,
+ .flags = IORESOURCE_MEM,
+ },
+ },
+ .id = -1,
+ .name = "dcih",
+ .type = INTEL_TH_OUTPUT,
+ },
+};
+
+static int intel_th_populate(struct intel_th *th, struct resource *devres,
+ unsigned int ndevres, int irq)
+{
+ struct resource res[3];
+ unsigned int req = 0;
+ int i, err;
+
+ /* create devices for each intel_th_subdevice */
+ for (i = 0; i < ARRAY_SIZE(intel_th_subdevices); i++) {
+ struct intel_th_subdevice *subdev = &intel_th_subdevices[i];
+ struct intel_th_device *thdev;
+ int r;
+
+ thdev = intel_th_device_alloc(th, subdev->type, subdev->name,
+ subdev->id);
+ if (!thdev) {
+ err = -ENOMEM;
+ goto kill_subdevs;
+ }
+
+ memcpy(res, subdev->res,
+ sizeof(struct resource) * subdev->nres);
+
+ for (r = 0; r < subdev->nres; r++) {
+ int bar = TH_MMIO_CONFIG;
+
+ /*
+ * Take .end == 0 to mean 'take the whole bar',
+ * .start then tells us which bar it is. Default to
+ * TH_MMIO_CONFIG.
+ */
+ if (!res[r].end && res[r].flags == IORESOURCE_MEM) {
+ bar = res[r].start;
+ res[r].start = 0;
+ res[r].end = resource_size(&devres[bar]) - 1;
+ }
+
+ if (res[r].flags & IORESOURCE_MEM) {
+ res[r].start += devres[bar].start;
+ res[r].end += devres[bar].start;
+
+ dev_dbg(th->dev, "%s:%d @ %pR\n",
+ subdev->name, r, &res[r]);
+ } else if (res[r].flags & IORESOURCE_IRQ) {
+ res[r].start = irq;
+ }
+ }
+
+ err = intel_th_device_add_resources(thdev, res, subdev->nres);
+ if (err) {
+ put_device(&thdev->dev);
+ goto kill_subdevs;
+ }
+
+ if (subdev->type == INTEL_TH_OUTPUT) {
+ thdev->dev.devt = MKDEV(th->major, i);
+ thdev->output.type = subdev->otype;
+ thdev->output.port = -1;
+ }
+
+ err = device_add(&thdev->dev);
+ if (err) {
+ put_device(&thdev->dev);
+ goto kill_subdevs;
+ }
+
+ /* need switch driver to be loaded to enumerate the rest */
+ if (subdev->type == INTEL_TH_SWITCH && !req) {
+ th->hub = thdev;
+ err = request_module("intel_th_%s", subdev->name);
+ if (!err)
+ req++;
+ }
+
+ th->thdev[i] = thdev;
+ }
+
+ return 0;
+
+kill_subdevs:
+ for (i-- ; i >= 0; i--)
+ intel_th_device_remove(th->thdev[i]);
+
+ return err;
+}
+
+static int match_devt(struct device *dev, void *data)
+{
+ dev_t devt = (dev_t)(unsigned long)data;
+
+ return dev->devt == devt;
+}
+
+static int intel_th_output_open(struct inode *inode, struct file *file)
+{
+ const struct file_operations *fops;
+ struct intel_th_driver *thdrv;
+ struct device *dev;
+ int err;
+
+ dev = bus_find_device(&intel_th_bus, NULL,
+ (void *)(unsigned long)inode->i_rdev,
+ match_devt);
+ if (!dev || !dev->driver)
+ return -ENODEV;
+
+ thdrv = to_intel_th_driver(dev->driver);
+ fops = fops_get(thdrv->fops);
+ if (!fops)
+ return -ENODEV;
+
+ replace_fops(file, fops);
+
+ file->private_data = to_intel_th_device(dev);
+
+ if (file->f_op->open) {
+ err = file->f_op->open(inode, file);
+ return err;
+ }
+
+ return 0;
+}
+
+static const struct file_operations intel_th_output_fops = {
+ .open = intel_th_output_open,
+ .llseek = noop_llseek,
+};
+
+/**
+ * intel_th_alloc() - allocate a new Intel TH device and its subdevices
+ * @dev: parent device
+ * @devres: parent's resources
+ * @ndevres: number of resources
+ * @irq: irq number
+ */
+struct intel_th *
+intel_th_alloc(struct device *dev, struct resource *devres,
+ unsigned int ndevres, int irq)
+{
+ struct intel_th *th;
+ int err;
+
+ th = kzalloc(sizeof(*th), GFP_KERNEL);
+ if (!th)
+ return ERR_PTR(-ENOMEM);
+
+ th->id = ida_simple_get(&intel_th_ida, 0, 0, GFP_KERNEL);
+ if (th->id < 0) {
+ err = th->id;
+ goto err_alloc;
+ }
+
+ th->major = __register_chrdev(0, 0, TH_POSSIBLE_OUTPUTS,
+ "intel_th/output", &intel_th_output_fops);
+ if (th->major < 0) {
+ err = th->major;
+ goto err_ida;
+ }
+ th->dev = dev;
+
+ err = intel_th_populate(th, devres, ndevres, irq);
+ if (err)
+ goto err_chrdev;
+
+ return th;
+
+err_chrdev:
+ __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
+ "intel_th/output");
+
+err_ida:
+ ida_simple_remove(&intel_th_ida, th->id);
+
+err_alloc:
+ kfree(th);
+
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(intel_th_alloc);
+
+void intel_th_free(struct intel_th *th)
+{
+ int i;
+
+ for (i = 0; i < TH_SUBDEVICE_MAX; i++)
+ if (th->thdev[i] != th->hub)
+ intel_th_device_remove(th->thdev[i]);
+
+ intel_th_device_remove(th->hub);
+
+ __unregister_chrdev(th->major, 0, TH_POSSIBLE_OUTPUTS,
+ "intel_th/output");
+
+ ida_simple_remove(&intel_th_ida, th->id);
+
+ kfree(th);
+}
+EXPORT_SYMBOL_GPL(intel_th_free);
+
+/**
+ * intel_th_trace_enable() - enable tracing for an output device
+ * @thdev: output device that requests tracing be enabled
+ */
+int intel_th_trace_enable(struct intel_th_device *thdev)
+{
+ struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
+ struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
+
+ if (WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH))
+ return -EINVAL;
+
+ if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
+ return -EINVAL;
+
+ hubdrv->enable(hub, &thdev->output);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(intel_th_trace_enable);
+
+/**
+ * intel_th_trace_disable() - disable tracing for an output device
+ * @thdev: output device that requests tracing be disabled
+ */
+int intel_th_trace_disable(struct intel_th_device *thdev)
+{
+ struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
+ struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
+
+ WARN_ON_ONCE(hub->type != INTEL_TH_SWITCH);
+ if (WARN_ON_ONCE(thdev->type != INTEL_TH_OUTPUT))
+ return -EINVAL;
+
+ hubdrv->disable(hub, &thdev->output);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(intel_th_trace_disable);
+
+int intel_th_set_output(struct intel_th_device *thdev,
+ unsigned int master)
+{
+ struct intel_th_device *hub = to_intel_th_device(thdev->dev.parent);
+ struct intel_th_driver *hubdrv = to_intel_th_driver(hub->dev.driver);
+
+ if (!hubdrv->set_output)
+ return -ENOTSUPP;
+
+ return hubdrv->set_output(hub, master);
+}
+EXPORT_SYMBOL_GPL(intel_th_set_output);
+
+static int __init intel_th_init(void)
+{
+ intel_th_debug_init();
+
+ return bus_register(&intel_th_bus);
+}
+subsys_initcall(intel_th_init);
+
+static void __exit intel_th_exit(void)
+{
+ intel_th_debug_done();
+
+ bus_unregister(&intel_th_bus);
+}
+module_exit(intel_th_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub controller driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/intel_th/debug.c b/drivers/hwtracing/intel_th/debug.c
new file mode 100644
index 000000000000..788a1f0a97ad
--- /dev/null
+++ b/drivers/hwtracing/intel_th/debug.c
@@ -0,0 +1,36 @@
+/*
+ * Intel(R) Trace Hub driver debugging
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <linux/types.h>
+#include <linux/device.h>
+#include <linux/debugfs.h>
+
+#include "intel_th.h"
+#include "debug.h"
+
+struct dentry *intel_th_dbg;
+
+void intel_th_debug_init(void)
+{
+ intel_th_dbg = debugfs_create_dir("intel_th", NULL);
+ if (IS_ERR(intel_th_dbg))
+ intel_th_dbg = NULL;
+}
+
+void intel_th_debug_done(void)
+{
+ debugfs_remove(intel_th_dbg);
+ intel_th_dbg = NULL;
+}
diff --git a/drivers/hwtracing/intel_th/debug.h b/drivers/hwtracing/intel_th/debug.h
new file mode 100644
index 000000000000..88311bad3ba4
--- /dev/null
+++ b/drivers/hwtracing/intel_th/debug.h
@@ -0,0 +1,34 @@
+/*
+ * Intel(R) Trace Hub driver debugging
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __INTEL_TH_DEBUG_H__
+#define __INTEL_TH_DEBUG_H__
+
+#ifdef CONFIG_INTEL_TH_DEBUG
+extern struct dentry *intel_th_dbg;
+
+void intel_th_debug_init(void);
+void intel_th_debug_done(void);
+#else
+static inline void intel_th_debug_init(void)
+{
+}
+
+static inline void intel_th_debug_done(void)
+{
+}
+#endif
+
+#endif /* __INTEL_TH_DEBUG_H__ */
diff --git a/drivers/hwtracing/intel_th/gth.c b/drivers/hwtracing/intel_th/gth.c
new file mode 100644
index 000000000000..2dc5378ccd3a
--- /dev/null
+++ b/drivers/hwtracing/intel_th/gth.c
@@ -0,0 +1,706 @@
+/*
+ * Intel(R) Trace Hub Global Trace Hub
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/bitmap.h>
+
+#include "intel_th.h"
+#include "gth.h"
+
+struct gth_device;
+
+/**
+ * struct gth_output - GTH view on an output port
+ * @gth: backlink to the GTH device
+ * @output: link to output device's output descriptor
+ * @index: output port number
+ * @port_type: one of GTH_* port type values
+ * @master: bitmap of masters configured for this output
+ */
+struct gth_output {
+ struct gth_device *gth;
+ struct intel_th_output *output;
+ unsigned int index;
+ unsigned int port_type;
+ DECLARE_BITMAP(master, TH_CONFIGURABLE_MASTERS + 1);
+};
+
+/**
+ * struct gth_device - GTH device
+ * @dev: driver core's device
+ * @base: register window base address
+ * @output_group: attributes describing output ports
+ * @master_group: attributes describing master assignments
+ * @output: output ports
+ * @master: master/output port assignments
+ * @gth_lock: serializes accesses to GTH bits
+ */
+struct gth_device {
+ struct device *dev;
+ void __iomem *base;
+
+ struct attribute_group output_group;
+ struct attribute_group master_group;
+ struct gth_output output[TH_POSSIBLE_OUTPUTS];
+ signed char master[TH_CONFIGURABLE_MASTERS + 1];
+ spinlock_t gth_lock;
+};
+
+static void gth_output_set(struct gth_device *gth, int port,
+ unsigned int config)
+{
+ unsigned long reg = port & 4 ? REG_GTH_GTHOPT1 : REG_GTH_GTHOPT0;
+ u32 val;
+ int shift = (port & 3) * 8;
+
+ val = ioread32(gth->base + reg);
+ val &= ~(0xff << shift);
+ val |= config << shift;
+ iowrite32(val, gth->base + reg);
+}
+
+static unsigned int gth_output_get(struct gth_device *gth, int port)
+{
+ unsigned long reg = port & 4 ? REG_GTH_GTHOPT1 : REG_GTH_GTHOPT0;
+ u32 val;
+ int shift = (port & 3) * 8;
+
+ val = ioread32(gth->base + reg);
+ val &= 0xff << shift;
+ val >>= shift;
+
+ return val;
+}
+
+static void gth_smcfreq_set(struct gth_device *gth, int port,
+ unsigned int freq)
+{
+ unsigned long reg = REG_GTH_SMCR0 + ((port / 2) * 4);
+ int shift = (port & 1) * 16;
+ u32 val;
+
+ val = ioread32(gth->base + reg);
+ val &= ~(0xffff << shift);
+ val |= freq << shift;
+ iowrite32(val, gth->base + reg);
+}
+
+static unsigned int gth_smcfreq_get(struct gth_device *gth, int port)
+{
+ unsigned long reg = REG_GTH_SMCR0 + ((port / 2) * 4);
+ int shift = (port & 1) * 16;
+ u32 val;
+
+ val = ioread32(gth->base + reg);
+ val &= 0xffff << shift;
+ val >>= shift;
+
+ return val;
+}
+
+/*
+ * "masters" attribute group
+ */
+
+struct master_attribute {
+ struct device_attribute attr;
+ struct gth_device *gth;
+ unsigned int master;
+};
+
+static void
+gth_master_set(struct gth_device *gth, unsigned int master, int port)
+{
+ unsigned int reg = REG_GTH_SWDEST0 + ((master >> 1) & ~3u);
+ unsigned int shift = (master & 0x7) * 4;
+ u32 val;
+
+ if (master >= 256) {
+ reg = REG_GTH_GSWTDEST;
+ shift = 0;
+ }
+
+ val = ioread32(gth->base + reg);
+ val &= ~(0xf << shift);
+ if (port >= 0)
+ val |= (0x8 | port) << shift;
+ iowrite32(val, gth->base + reg);
+}
+
+/*static int gth_master_get(struct gth_device *gth, unsigned int master)
+{
+ unsigned int reg = REG_GTH_SWDEST0 + ((master >> 1) & ~3u);
+ unsigned int shift = (master & 0x7) * 4;
+ u32 val;
+
+ if (master >= 256) {
+ reg = REG_GTH_GSWTDEST;
+ shift = 0;
+ }
+
+ val = ioread32(gth->base + reg);
+ val &= (0xf << shift);
+ val >>= shift;
+
+ return val ? val & 0x7 : -1;
+ }*/
+
+static ssize_t master_attr_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct master_attribute *ma =
+ container_of(attr, struct master_attribute, attr);
+ struct gth_device *gth = ma->gth;
+ size_t count;
+ int port;
+
+ spin_lock(&gth->gth_lock);
+ port = gth->master[ma->master];
+ spin_unlock(&gth->gth_lock);
+
+ if (port >= 0)
+ count = snprintf(buf, PAGE_SIZE, "%x\n", port);
+ else
+ count = snprintf(buf, PAGE_SIZE, "disabled\n");
+
+ return count;
+}
+
+static ssize_t master_attr_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct master_attribute *ma =
+ container_of(attr, struct master_attribute, attr);
+ struct gth_device *gth = ma->gth;
+ int old_port, port;
+
+ if (kstrtoint(buf, 10, &port) < 0)
+ return -EINVAL;
+
+ if (port >= TH_POSSIBLE_OUTPUTS || port < -1)
+ return -EINVAL;
+
+ spin_lock(&gth->gth_lock);
+
+ /* disconnect from the previous output port, if any */
+ old_port = gth->master[ma->master];
+ if (old_port >= 0) {
+ gth->master[ma->master] = -1;
+ clear_bit(ma->master, gth->output[old_port].master);
+ if (gth->output[old_port].output->active)
+ gth_master_set(gth, ma->master, -1);
+ }
+
+ /* connect to the new output port, if any */
+ if (port >= 0) {
+ /* check if there's a driver for this port */
+ if (!gth->output[port].output) {
+ count = -ENODEV;
+ goto unlock;
+ }
+
+ set_bit(ma->master, gth->output[port].master);
+
+ /* if the port is active, program this setting */
+ if (gth->output[port].output->active)
+ gth_master_set(gth, ma->master, port);
+ }
+
+ gth->master[ma->master] = port;
+
+unlock:
+ spin_unlock(&gth->gth_lock);
+
+ return count;
+}
+
+struct output_attribute {
+ struct device_attribute attr;
+ struct gth_device *gth;
+ unsigned int port;
+ unsigned int parm;
+};
+
+#define OUTPUT_PARM(_name, _mask, _r, _w, _what) \
+ [TH_OUTPUT_PARM(_name)] = { .name = __stringify(_name), \
+ .get = gth_ ## _what ## _get, \
+ .set = gth_ ## _what ## _set, \
+ .mask = (_mask), \
+ .readable = (_r), \
+ .writable = (_w) }
+
+static const struct output_parm {
+ const char *name;
+ unsigned int (*get)(struct gth_device *gth, int port);
+ void (*set)(struct gth_device *gth, int port,
+ unsigned int val);
+ unsigned int mask;
+ unsigned int readable : 1,
+ writable : 1;
+} output_parms[] = {
+ OUTPUT_PARM(port, 0x7, 1, 0, output),
+ OUTPUT_PARM(null, BIT(3), 1, 1, output),
+ OUTPUT_PARM(drop, BIT(4), 1, 1, output),
+ OUTPUT_PARM(reset, BIT(5), 1, 0, output),
+ OUTPUT_PARM(flush, BIT(7), 0, 1, output),
+ OUTPUT_PARM(smcfreq, 0xffff, 1, 1, smcfreq),
+};
+
+static void
+gth_output_parm_set(struct gth_device *gth, int port, unsigned int parm,
+ unsigned int val)
+{
+ unsigned int config = output_parms[parm].get(gth, port);
+ unsigned int mask = output_parms[parm].mask;
+ unsigned int shift = __ffs(mask);
+
+ config &= ~mask;
+ config |= (val << shift) & mask;
+ output_parms[parm].set(gth, port, config);
+}
+
+static unsigned int
+gth_output_parm_get(struct gth_device *gth, int port, unsigned int parm)
+{
+ unsigned int config = output_parms[parm].get(gth, port);
+ unsigned int mask = output_parms[parm].mask;
+ unsigned int shift = __ffs(mask);
+
+ config &= mask;
+ config >>= shift;
+ return config;
+}
+
+/*
+ * Reset outputs and sources
+ */
+static int intel_th_gth_reset(struct gth_device *gth)
+{
+ u32 scratchpad;
+ int port, i;
+
+ scratchpad = ioread32(gth->base + REG_GTH_SCRPD0);
+ if (scratchpad & SCRPD_DEBUGGER_IN_USE)
+ return -EBUSY;
+
+ /* output ports */
+ for (port = 0; port < 8; port++) {
+ if (gth_output_parm_get(gth, port, TH_OUTPUT_PARM(port)) ==
+ GTH_NONE)
+ continue;
+
+ gth_output_set(gth, port, 0);
+ gth_smcfreq_set(gth, port, 16);
+ }
+ /* disable overrides */
+ iowrite32(0, gth->base + REG_GTH_DESTOVR);
+
+ /* masters swdest_0~31 and gswdest */
+ for (i = 0; i < 33; i++)
+ iowrite32(0, gth->base + REG_GTH_SWDEST0 + i * 4);
+
+ /* sources */
+ iowrite32(0, gth->base + REG_GTH_SCR);
+ iowrite32(0xfc, gth->base + REG_GTH_SCR2);
+
+ return 0;
+}
+
+/*
+ * "outputs" attribute group
+ */
+
+static ssize_t output_attr_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct output_attribute *oa =
+ container_of(attr, struct output_attribute, attr);
+ struct gth_device *gth = oa->gth;
+ size_t count;
+
+ spin_lock(&gth->gth_lock);
+ count = snprintf(buf, PAGE_SIZE, "%x\n",
+ gth_output_parm_get(gth, oa->port, oa->parm));
+ spin_unlock(&gth->gth_lock);
+
+ return count;
+}
+
+static ssize_t output_attr_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct output_attribute *oa =
+ container_of(attr, struct output_attribute, attr);
+ struct gth_device *gth = oa->gth;
+ unsigned int config;
+
+ if (kstrtouint(buf, 16, &config) < 0)
+ return -EINVAL;
+
+ spin_lock(&gth->gth_lock);
+ gth_output_parm_set(gth, oa->port, oa->parm, config);
+ spin_unlock(&gth->gth_lock);
+
+ return count;
+}
+
+static int intel_th_master_attributes(struct gth_device *gth)
+{
+ struct master_attribute *master_attrs;
+ struct attribute **attrs;
+ int i, nattrs = TH_CONFIGURABLE_MASTERS + 2;
+
+ attrs = devm_kcalloc(gth->dev, nattrs, sizeof(void *), GFP_KERNEL);
+ if (!attrs)
+ return -ENOMEM;
+
+ master_attrs = devm_kcalloc(gth->dev, nattrs,
+ sizeof(struct master_attribute),
+ GFP_KERNEL);
+ if (!master_attrs)
+ return -ENOMEM;
+
+ for (i = 0; i < TH_CONFIGURABLE_MASTERS + 1; i++) {
+ char *name;
+
+ name = devm_kasprintf(gth->dev, GFP_KERNEL, "%d%s", i,
+ i == TH_CONFIGURABLE_MASTERS ? "+" : "");
+ if (!name)
+ return -ENOMEM;
+
+ master_attrs[i].attr.attr.name = name;
+ master_attrs[i].attr.attr.mode = S_IRUGO | S_IWUSR;
+ master_attrs[i].attr.show = master_attr_show;
+ master_attrs[i].attr.store = master_attr_store;
+
+ sysfs_attr_init(&master_attrs[i].attr.attr);
+ attrs[i] = &master_attrs[i].attr.attr;
+
+ master_attrs[i].gth = gth;
+ master_attrs[i].master = i;
+ }
+
+ gth->master_group.name = "masters";
+ gth->master_group.attrs = attrs;
+
+ return sysfs_create_group(&gth->dev->kobj, &gth->master_group);
+}
+
+static int intel_th_output_attributes(struct gth_device *gth)
+{
+ struct output_attribute *out_attrs;
+ struct attribute **attrs;
+ int i, j, nouts = TH_POSSIBLE_OUTPUTS;
+ int nparms = ARRAY_SIZE(output_parms);
+ int nattrs = nouts * nparms + 1;
+
+ attrs = devm_kcalloc(gth->dev, nattrs, sizeof(void *), GFP_KERNEL);
+ if (!attrs)
+ return -ENOMEM;
+
+ out_attrs = devm_kcalloc(gth->dev, nattrs,
+ sizeof(struct output_attribute),
+ GFP_KERNEL);
+ if (!out_attrs)
+ return -ENOMEM;
+
+ for (i = 0; i < nouts; i++) {
+ for (j = 0; j < nparms; j++) {
+ unsigned int idx = i * nparms + j;
+ char *name;
+
+ name = devm_kasprintf(gth->dev, GFP_KERNEL, "%d_%s", i,
+ output_parms[j].name);
+ if (!name)
+ return -ENOMEM;
+
+ out_attrs[idx].attr.attr.name = name;
+
+ if (output_parms[j].readable) {
+ out_attrs[idx].attr.attr.mode |= S_IRUGO;
+ out_attrs[idx].attr.show = output_attr_show;
+ }
+
+ if (output_parms[j].writable) {
+ out_attrs[idx].attr.attr.mode |= S_IWUSR;
+ out_attrs[idx].attr.store = output_attr_store;
+ }
+
+ sysfs_attr_init(&out_attrs[idx].attr.attr);
+ attrs[idx] = &out_attrs[idx].attr.attr;
+
+ out_attrs[idx].gth = gth;
+ out_attrs[idx].port = i;
+ out_attrs[idx].parm = j;
+ }
+ }
+
+ gth->output_group.name = "outputs";
+ gth->output_group.attrs = attrs;
+
+ return sysfs_create_group(&gth->dev->kobj, &gth->output_group);
+}
+
+/**
+ * intel_th_gth_disable() - enable tracing to an output device
+ * @thdev: GTH device
+ * @output: output device's descriptor
+ *
+ * This will deconfigure all masters set to output to this device,
+ * disable tracing using force storeEn off signal and wait for the
+ * "pipeline empty" bit for corresponding output port.
+ */
+static void intel_th_gth_disable(struct intel_th_device *thdev,
+ struct intel_th_output *output)
+{
+ struct gth_device *gth = dev_get_drvdata(&thdev->dev);
+ unsigned long count;
+ int master;
+ u32 reg;
+
+ spin_lock(&gth->gth_lock);
+ output->active = false;
+
+ for_each_set_bit(master, gth->output[output->port].master,
+ TH_CONFIGURABLE_MASTERS) {
+ gth_master_set(gth, master, -1);
+ }
+ spin_unlock(&gth->gth_lock);
+
+ iowrite32(0, gth->base + REG_GTH_SCR);
+ iowrite32(0xfd, gth->base + REG_GTH_SCR2);
+
+ /* wait on pipeline empty for the given port */
+ for (reg = 0, count = GTH_PLE_WAITLOOP_DEPTH;
+ count && !(reg & BIT(output->port)); count--) {
+ reg = ioread32(gth->base + REG_GTH_STAT);
+ cpu_relax();
+ }
+
+ /* clear force capture done for next captures */
+ iowrite32(0xfc, gth->base + REG_GTH_SCR2);
+
+ if (!count)
+ dev_dbg(&thdev->dev, "timeout waiting for GTH[%d] PLE\n",
+ output->port);
+}
+
+/**
+ * intel_th_gth_enable() - enable tracing to an output device
+ * @thdev: GTH device
+ * @output: output device's descriptor
+ *
+ * This will configure all masters set to output to this device and
+ * enable tracing using force storeEn signal.
+ */
+static void intel_th_gth_enable(struct intel_th_device *thdev,
+ struct intel_th_output *output)
+{
+ struct gth_device *gth = dev_get_drvdata(&thdev->dev);
+ u32 scr = 0xfc0000;
+ int master;
+
+ spin_lock(&gth->gth_lock);
+ for_each_set_bit(master, gth->output[output->port].master,
+ TH_CONFIGURABLE_MASTERS + 1) {
+ gth_master_set(gth, master, output->port);
+ }
+
+ if (output->multiblock)
+ scr |= 0xff;
+
+ output->active = true;
+ spin_unlock(&gth->gth_lock);
+
+ iowrite32(scr, gth->base + REG_GTH_SCR);
+ iowrite32(0, gth->base + REG_GTH_SCR2);
+}
+
+/**
+ * intel_th_gth_assign() - assign output device to a GTH output port
+ * @thdev: GTH device
+ * @othdev: output device
+ *
+ * This will match a given output device parameters against present
+ * output ports on the GTH and fill out relevant bits in output device's
+ * descriptor.
+ *
+ * Return: 0 on success, -errno on error.
+ */
+static int intel_th_gth_assign(struct intel_th_device *thdev,
+ struct intel_th_device *othdev)
+{
+ struct gth_device *gth = dev_get_drvdata(&thdev->dev);
+ int i, id;
+
+ if (othdev->type != INTEL_TH_OUTPUT)
+ return -EINVAL;
+
+ for (i = 0, id = 0; i < TH_POSSIBLE_OUTPUTS; i++) {
+ if (gth->output[i].port_type != othdev->output.type)
+ continue;
+
+ if (othdev->id == -1 || othdev->id == id)
+ goto found;
+
+ id++;
+ }
+
+ return -ENOENT;
+
+found:
+ spin_lock(&gth->gth_lock);
+ othdev->output.port = i;
+ othdev->output.active = false;
+ gth->output[i].output = &othdev->output;
+ spin_unlock(&gth->gth_lock);
+
+ return 0;
+}
+
+/**
+ * intel_th_gth_unassign() - deassociate an output device from its output port
+ * @thdev: GTH device
+ * @othdev: output device
+ */
+static void intel_th_gth_unassign(struct intel_th_device *thdev,
+ struct intel_th_device *othdev)
+{
+ struct gth_device *gth = dev_get_drvdata(&thdev->dev);
+ int port = othdev->output.port;
+
+ spin_lock(&gth->gth_lock);
+ othdev->output.port = -1;
+ othdev->output.active = false;
+ gth->output[port].output = NULL;
+ spin_unlock(&gth->gth_lock);
+}
+
+static int
+intel_th_gth_set_output(struct intel_th_device *thdev, unsigned int master)
+{
+ struct gth_device *gth = dev_get_drvdata(&thdev->dev);
+ int port = 0; /* FIXME: make default output configurable */
+
+ /*
+ * everything above TH_CONFIGURABLE_MASTERS is controlled by the
+ * same register
+ */
+ if (master > TH_CONFIGURABLE_MASTERS)
+ master = TH_CONFIGURABLE_MASTERS;
+
+ spin_lock(&gth->gth_lock);
+ if (gth->master[master] == -1) {
+ set_bit(master, gth->output[port].master);
+ gth->master[master] = port;
+ }
+ spin_unlock(&gth->gth_lock);
+
+ return 0;
+}
+
+static int intel_th_gth_probe(struct intel_th_device *thdev)
+{
+ struct device *dev = &thdev->dev;
+ struct gth_device *gth;
+ struct resource *res;
+ void __iomem *base;
+ int i, ret;
+
+ res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ gth = devm_kzalloc(dev, sizeof(*gth), GFP_KERNEL);
+ if (!gth)
+ return -ENOMEM;
+
+ gth->dev = dev;
+ gth->base = base;
+ spin_lock_init(&gth->gth_lock);
+
+ ret = intel_th_gth_reset(gth);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < TH_CONFIGURABLE_MASTERS + 1; i++)
+ gth->master[i] = -1;
+
+ for (i = 0; i < TH_POSSIBLE_OUTPUTS; i++) {
+ gth->output[i].gth = gth;
+ gth->output[i].index = i;
+ gth->output[i].port_type =
+ gth_output_parm_get(gth, i, TH_OUTPUT_PARM(port));
+ }
+
+ if (intel_th_output_attributes(gth) ||
+ intel_th_master_attributes(gth)) {
+ pr_warn("Can't initialize sysfs attributes\n");
+
+ if (gth->output_group.attrs)
+ sysfs_remove_group(&gth->dev->kobj, &gth->output_group);
+ return -ENOMEM;
+ }
+
+ dev_set_drvdata(dev, gth);
+
+ return 0;
+}
+
+static void intel_th_gth_remove(struct intel_th_device *thdev)
+{
+ struct gth_device *gth = dev_get_drvdata(&thdev->dev);
+
+ sysfs_remove_group(&gth->dev->kobj, &gth->output_group);
+ sysfs_remove_group(&gth->dev->kobj, &gth->master_group);
+}
+
+static struct intel_th_driver intel_th_gth_driver = {
+ .probe = intel_th_gth_probe,
+ .remove = intel_th_gth_remove,
+ .assign = intel_th_gth_assign,
+ .unassign = intel_th_gth_unassign,
+ .set_output = intel_th_gth_set_output,
+ .enable = intel_th_gth_enable,
+ .disable = intel_th_gth_disable,
+ .driver = {
+ .name = "gth",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_driver(intel_th_gth_driver,
+ intel_th_driver_register,
+ intel_th_driver_unregister);
+
+MODULE_ALIAS("intel_th_switch");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub Global Trace Hub driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/intel_th/gth.h b/drivers/hwtracing/intel_th/gth.h
new file mode 100644
index 000000000000..3b714b7a61db
--- /dev/null
+++ b/drivers/hwtracing/intel_th/gth.h
@@ -0,0 +1,66 @@
+/*
+ * Intel(R) Trace Hub Global Trace Hub (GTH) data structures
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __INTEL_TH_GTH_H__
+#define __INTEL_TH_GTH_H__
+
+/* Map output port parameter bits to symbolic names */
+#define TH_OUTPUT_PARM(name) \
+ TH_OUTPUT_ ## name
+
+enum intel_th_output_parm {
+ /* output port type */
+ TH_OUTPUT_PARM(port),
+ /* generate NULL packet */
+ TH_OUTPUT_PARM(null),
+ /* packet drop */
+ TH_OUTPUT_PARM(drop),
+ /* port in reset state */
+ TH_OUTPUT_PARM(reset),
+ /* flush out data */
+ TH_OUTPUT_PARM(flush),
+ /* mainenance packet frequency */
+ TH_OUTPUT_PARM(smcfreq),
+};
+
+/*
+ * Register offsets
+ */
+enum {
+ REG_GTH_GTHOPT0 = 0x00, /* Output ports 0..3 config */
+ REG_GTH_GTHOPT1 = 0x04, /* Output ports 4..7 config */
+ REG_GTH_SWDEST0 = 0x08, /* Switching destination masters 0..7 */
+ REG_GTH_GSWTDEST = 0x88, /* Global sw trace destination */
+ REG_GTH_SMCR0 = 0x9c, /* STP mainenance for ports 0/1 */
+ REG_GTH_SMCR1 = 0xa0, /* STP mainenance for ports 2/3 */
+ REG_GTH_SMCR2 = 0xa4, /* STP mainenance for ports 4/5 */
+ REG_GTH_SMCR3 = 0xa8, /* STP mainenance for ports 6/7 */
+ REG_GTH_SCR = 0xc8, /* Source control (storeEn override) */
+ REG_GTH_STAT = 0xd4, /* GTH status */
+ REG_GTH_SCR2 = 0xd8, /* Source control (force storeEn off) */
+ REG_GTH_DESTOVR = 0xdc, /* Destination override */
+ REG_GTH_SCRPD0 = 0xe0, /* ScratchPad[0] */
+ REG_GTH_SCRPD1 = 0xe4, /* ScratchPad[1] */
+ REG_GTH_SCRPD2 = 0xe8, /* ScratchPad[2] */
+ REG_GTH_SCRPD3 = 0xec, /* ScratchPad[3] */
+};
+
+/* Externall debugger is using Intel TH */
+#define SCRPD_DEBUGGER_IN_USE BIT(24)
+
+/* waiting for Pipeline Empty bit(s) to assert for GTH */
+#define GTH_PLE_WAITLOOP_DEPTH 10000
+
+#endif /* __INTEL_TH_GTH_H__ */
diff --git a/drivers/hwtracing/intel_th/intel_th.h b/drivers/hwtracing/intel_th/intel_th.h
new file mode 100644
index 000000000000..57fd72b20fae
--- /dev/null
+++ b/drivers/hwtracing/intel_th/intel_th.h
@@ -0,0 +1,244 @@
+/*
+ * Intel(R) Trace Hub data structures
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __INTEL_TH_H__
+#define __INTEL_TH_H__
+
+/* intel_th_device device types */
+enum {
+ /* Devices that generate trace data */
+ INTEL_TH_SOURCE = 0,
+ /* Output ports (MSC, PTI) */
+ INTEL_TH_OUTPUT,
+ /* Switch, the Global Trace Hub (GTH) */
+ INTEL_TH_SWITCH,
+};
+
+/**
+ * struct intel_th_output - descriptor INTEL_TH_OUTPUT type devices
+ * @port: output port number, assigned by the switch
+ * @type: GTH_{MSU,CTP,PTI}
+ * @multiblock: true for multiblock output configuration
+ * @active: true when this output is enabled
+ *
+ * Output port descriptor, used by switch driver to tell which output
+ * port this output device corresponds to. Filled in at output device's
+ * probe time by switch::assign(). Passed from output device driver to
+ * switch related code to enable/disable its port.
+ */
+struct intel_th_output {
+ int port;
+ unsigned int type;
+ bool multiblock;
+ bool active;
+};
+
+/**
+ * struct intel_th_device - device on the intel_th bus
+ * @dev: device
+ * @resource: array of resources available to this device
+ * @num_resources: number of resources in @resource array
+ * @type: INTEL_TH_{SOURCE,OUTPUT,SWITCH}
+ * @id: device instance or -1
+ * @output: output descriptor for INTEL_TH_OUTPUT devices
+ * @name: device name to match the driver
+ */
+struct intel_th_device {
+ struct device dev;
+ struct resource *resource;
+ unsigned int num_resources;
+ unsigned int type;
+ int id;
+
+ /* INTEL_TH_OUTPUT specific */
+ struct intel_th_output output;
+
+ char name[];
+};
+
+#define to_intel_th_device(_d) \
+ container_of((_d), struct intel_th_device, dev)
+
+/**
+ * intel_th_device_get_resource() - obtain @num'th resource of type @type
+ * @thdev: the device to search the resource for
+ * @type: resource type
+ * @num: number of the resource
+ */
+static inline struct resource *
+intel_th_device_get_resource(struct intel_th_device *thdev, unsigned int type,
+ unsigned int num)
+{
+ int i;
+
+ for (i = 0; i < thdev->num_resources; i++)
+ if (resource_type(&thdev->resource[i]) == type && !num--)
+ return &thdev->resource[i];
+
+ return NULL;
+}
+
+/**
+ * intel_th_output_assigned() - if an output device is assigned to a switch port
+ * @thdev: the output device
+ *
+ * Return: true if the device is INTEL_TH_OUTPUT *and* is assigned a port
+ */
+static inline bool
+intel_th_output_assigned(struct intel_th_device *thdev)
+{
+ return thdev->type == INTEL_TH_OUTPUT &&
+ thdev->output.port >= 0;
+}
+
+/**
+ * struct intel_th_driver - driver for an intel_th_device device
+ * @driver: generic driver
+ * @probe: probe method
+ * @remove: remove method
+ * @assign: match a given output type device against available outputs
+ * @unassign: deassociate an output type device from an output port
+ * @enable: enable tracing for a given output device
+ * @disable: disable tracing for a given output device
+ * @fops: file operations for device nodes
+ *
+ * Callbacks @probe and @remove are required for all device types.
+ * Switch device driver needs to fill in @assign, @enable and @disable
+ * callbacks.
+ */
+struct intel_th_driver {
+ struct device_driver driver;
+ int (*probe)(struct intel_th_device *thdev);
+ void (*remove)(struct intel_th_device *thdev);
+ /* switch (GTH) ops */
+ int (*assign)(struct intel_th_device *thdev,
+ struct intel_th_device *othdev);
+ void (*unassign)(struct intel_th_device *thdev,
+ struct intel_th_device *othdev);
+ void (*enable)(struct intel_th_device *thdev,
+ struct intel_th_output *output);
+ void (*disable)(struct intel_th_device *thdev,
+ struct intel_th_output *output);
+ /* output ops */
+ void (*irq)(struct intel_th_device *thdev);
+ int (*activate)(struct intel_th_device *thdev);
+ void (*deactivate)(struct intel_th_device *thdev);
+ /* file_operations for those who want a device node */
+ const struct file_operations *fops;
+
+ /* source ops */
+ int (*set_output)(struct intel_th_device *thdev,
+ unsigned int master);
+};
+
+#define to_intel_th_driver(_d) \
+ container_of((_d), struct intel_th_driver, driver)
+
+static inline struct intel_th_device *
+to_intel_th_hub(struct intel_th_device *thdev)
+{
+ struct device *parent = thdev->dev.parent;
+
+ if (!parent)
+ return NULL;
+
+ return to_intel_th_device(parent);
+}
+
+struct intel_th *
+intel_th_alloc(struct device *dev, struct resource *devres,
+ unsigned int ndevres, int irq);
+void intel_th_free(struct intel_th *th);
+
+int intel_th_driver_register(struct intel_th_driver *thdrv);
+void intel_th_driver_unregister(struct intel_th_driver *thdrv);
+
+int intel_th_trace_enable(struct intel_th_device *thdev);
+int intel_th_trace_disable(struct intel_th_device *thdev);
+int intel_th_set_output(struct intel_th_device *thdev,
+ unsigned int master);
+
+enum {
+ TH_MMIO_CONFIG = 0,
+ TH_MMIO_SW = 2,
+ TH_MMIO_END,
+};
+
+#define TH_SUBDEVICE_MAX 6
+#define TH_POSSIBLE_OUTPUTS 8
+#define TH_CONFIGURABLE_MASTERS 256
+#define TH_MSC_MAX 2
+
+/**
+ * struct intel_th - Intel TH controller
+ * @dev: driver core's device
+ * @thdev: subdevices
+ * @hub: "switch" subdevice (GTH)
+ * @id: this Intel TH controller's device ID in the system
+ * @major: device node major for output devices
+ */
+struct intel_th {
+ struct device *dev;
+
+ struct intel_th_device *thdev[TH_SUBDEVICE_MAX];
+ struct intel_th_device *hub;
+
+ int id;
+ int major;
+#ifdef CONFIG_INTEL_TH_DEBUG
+ struct dentry *dbg;
+#endif
+};
+
+/*
+ * Register windows
+ */
+enum {
+ /* Global Trace Hub (GTH) */
+ REG_GTH_OFFSET = 0x0000,
+ REG_GTH_LENGTH = 0x2000,
+
+ /* Software Trace Hub (STH) [0x4000..0x4fff] */
+ REG_STH_OFFSET = 0x4000,
+ REG_STH_LENGTH = 0x2000,
+
+ /* Memory Storage Unit (MSU) [0xa0000..0xa1fff] */
+ REG_MSU_OFFSET = 0xa0000,
+ REG_MSU_LENGTH = 0x02000,
+
+ /* Internal MSU trace buffer [0x80000..0x9ffff] */
+ BUF_MSU_OFFSET = 0x80000,
+ BUF_MSU_LENGTH = 0x20000,
+
+ /* PTI output == same window as GTH */
+ REG_PTI_OFFSET = REG_GTH_OFFSET,
+ REG_PTI_LENGTH = REG_GTH_LENGTH,
+
+ /* DCI Handler (DCIH) == some window as MSU */
+ REG_DCIH_OFFSET = REG_MSU_OFFSET,
+ REG_DCIH_LENGTH = REG_MSU_LENGTH,
+};
+
+/*
+ * GTH, output ports configuration
+ */
+enum {
+ GTH_NONE = 0,
+ GTH_MSU, /* memory/usb */
+ GTH_CTP, /* Common Trace Port */
+ GTH_PTI = 4, /* MIPI-PTI */
+};
+
+#endif
diff --git a/drivers/hwtracing/intel_th/msu.c b/drivers/hwtracing/intel_th/msu.c
new file mode 100644
index 000000000000..70ca27e45602
--- /dev/null
+++ b/drivers/hwtracing/intel_th/msu.c
@@ -0,0 +1,1509 @@
+/*
+ * Intel(R) Trace Hub Memory Storage Unit
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/uaccess.h>
+#include <linux/sizes.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/fs.h>
+#include <linux/io.h>
+#include <linux/dma-mapping.h>
+
+#include <asm/cacheflush.h>
+
+#include "intel_th.h"
+#include "msu.h"
+
+#define msc_dev(x) (&(x)->thdev->dev)
+
+/**
+ * struct msc_block - multiblock mode block descriptor
+ * @bdesc: pointer to hardware descriptor (beginning of the block)
+ * @addr: physical address of the block
+ */
+struct msc_block {
+ struct msc_block_desc *bdesc;
+ dma_addr_t addr;
+};
+
+/**
+ * struct msc_window - multiblock mode window descriptor
+ * @entry: window list linkage (msc::win_list)
+ * @pgoff: page offset into the buffer that this window starts at
+ * @nr_blocks: number of blocks (pages) in this window
+ * @block: array of block descriptors
+ */
+struct msc_window {
+ struct list_head entry;
+ unsigned long pgoff;
+ unsigned int nr_blocks;
+ struct msc *msc;
+ struct msc_block block[0];
+};
+
+/**
+ * struct msc_iter - iterator for msc buffer
+ * @entry: msc::iter_list linkage
+ * @msc: pointer to the MSC device
+ * @start_win: oldest window
+ * @win: current window
+ * @offset: current logical offset into the buffer
+ * @start_block: oldest block in the window
+ * @block: block number in the window
+ * @block_off: offset into current block
+ * @wrap_count: block wrapping handling
+ * @eof: end of buffer reached
+ */
+struct msc_iter {
+ struct list_head entry;
+ struct msc *msc;
+ struct msc_window *start_win;
+ struct msc_window *win;
+ unsigned long offset;
+ int start_block;
+ int block;
+ unsigned int block_off;
+ unsigned int wrap_count;
+ unsigned int eof;
+};
+
+/**
+ * struct msc - MSC device representation
+ * @reg_base: register window base address
+ * @thdev: intel_th_device pointer
+ * @win_list: list of windows in multiblock mode
+ * @nr_pages: total number of pages allocated for this buffer
+ * @single_sz: amount of data in single mode
+ * @single_wrap: single mode wrap occurred
+ * @base: buffer's base pointer
+ * @base_addr: buffer's base address
+ * @user_count: number of users of the buffer
+ * @mmap_count: number of mappings
+ * @buf_mutex: mutex to serialize access to buffer-related bits
+
+ * @enabled: MSC is enabled
+ * @wrap: wrapping is enabled
+ * @mode: MSC operating mode
+ * @burst_len: write burst length
+ * @index: number of this MSC in the MSU
+ */
+struct msc {
+ void __iomem *reg_base;
+ struct intel_th_device *thdev;
+
+ struct list_head win_list;
+ unsigned long nr_pages;
+ unsigned long single_sz;
+ unsigned int single_wrap : 1;
+ void *base;
+ dma_addr_t base_addr;
+
+ /* <0: no buffer, 0: no users, >0: active users */
+ atomic_t user_count;
+
+ atomic_t mmap_count;
+ struct mutex buf_mutex;
+
+ struct mutex iter_mutex;
+ struct list_head iter_list;
+
+ /* config */
+ unsigned int enabled : 1,
+ wrap : 1;
+ unsigned int mode;
+ unsigned int burst_len;
+ unsigned int index;
+};
+
+static inline bool msc_block_is_empty(struct msc_block_desc *bdesc)
+{
+ /* header hasn't been written */
+ if (!bdesc->valid_dw)
+ return true;
+
+ /* valid_dw includes the header */
+ if (!msc_data_sz(bdesc))
+ return true;
+
+ return false;
+}
+
+/**
+ * msc_oldest_window() - locate the window with oldest data
+ * @msc: MSC device
+ *
+ * This should only be used in multiblock mode. Caller should hold the
+ * msc::user_count reference.
+ *
+ * Return: the oldest window with valid data
+ */
+static struct msc_window *msc_oldest_window(struct msc *msc)
+{
+ struct msc_window *win;
+ u32 reg = ioread32(msc->reg_base + REG_MSU_MSC0NWSA);
+ unsigned long win_addr = (unsigned long)reg << PAGE_SHIFT;
+ unsigned int found = 0;
+
+ if (list_empty(&msc->win_list))
+ return NULL;
+
+ /*
+ * we might need a radix tree for this, depending on how
+ * many windows a typical user would allocate; ideally it's
+ * something like 2, in which case we're good
+ */
+ list_for_each_entry(win, &msc->win_list, entry) {
+ if (win->block[0].addr == win_addr)
+ found++;
+
+ /* skip the empty ones */
+ if (msc_block_is_empty(win->block[0].bdesc))
+ continue;
+
+ if (found)
+ return win;
+ }
+
+ return list_entry(msc->win_list.next, struct msc_window, entry);
+}
+
+/**
+ * msc_win_oldest_block() - locate the oldest block in a given window
+ * @win: window to look at
+ *
+ * Return: index of the block with the oldest data
+ */
+static unsigned int msc_win_oldest_block(struct msc_window *win)
+{
+ unsigned int blk;
+ struct msc_block_desc *bdesc = win->block[0].bdesc;
+
+ /* without wrapping, first block is the oldest */
+ if (!msc_block_wrapped(bdesc))
+ return 0;
+
+ /*
+ * with wrapping, last written block contains both the newest and the
+ * oldest data for this window.
+ */
+ for (blk = 0; blk < win->nr_blocks; blk++) {
+ bdesc = win->block[blk].bdesc;
+
+ if (msc_block_last_written(bdesc))
+ return blk;
+ }
+
+ return 0;
+}
+
+/**
+ * msc_is_last_win() - check if a window is the last one for a given MSC
+ * @win: window
+ * Return: true if @win is the last window in MSC's multiblock buffer
+ */
+static inline bool msc_is_last_win(struct msc_window *win)
+{
+ return win->entry.next == &win->msc->win_list;
+}
+
+/**
+ * msc_next_window() - return next window in the multiblock buffer
+ * @win: current window
+ *
+ * Return: window following the current one
+ */
+static struct msc_window *msc_next_window(struct msc_window *win)
+{
+ if (msc_is_last_win(win))
+ return list_entry(win->msc->win_list.next, struct msc_window,
+ entry);
+
+ return list_entry(win->entry.next, struct msc_window, entry);
+}
+
+static struct msc_block_desc *msc_iter_bdesc(struct msc_iter *iter)
+{
+ return iter->win->block[iter->block].bdesc;
+}
+
+static void msc_iter_init(struct msc_iter *iter)
+{
+ memset(iter, 0, sizeof(*iter));
+ iter->start_block = -1;
+ iter->block = -1;
+}
+
+static struct msc_iter *msc_iter_install(struct msc *msc)
+{
+ struct msc_iter *iter;
+
+ iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+ if (!iter)
+ return NULL;
+
+ msc_iter_init(iter);
+ iter->msc = msc;
+
+ mutex_lock(&msc->iter_mutex);
+ list_add_tail(&iter->entry, &msc->iter_list);
+ mutex_unlock(&msc->iter_mutex);
+
+ return iter;
+}
+
+static void msc_iter_remove(struct msc_iter *iter, struct msc *msc)
+{
+ mutex_lock(&msc->iter_mutex);
+ list_del(&iter->entry);
+ mutex_unlock(&msc->iter_mutex);
+
+ kfree(iter);
+}
+
+static void msc_iter_block_start(struct msc_iter *iter)
+{
+ if (iter->start_block != -1)
+ return;
+
+ iter->start_block = msc_win_oldest_block(iter->win);
+ iter->block = iter->start_block;
+ iter->wrap_count = 0;
+
+ /*
+ * start with the block with oldest data; if data has wrapped
+ * in this window, it should be in this block
+ */
+ if (msc_block_wrapped(msc_iter_bdesc(iter)))
+ iter->wrap_count = 2;
+
+}
+
+static int msc_iter_win_start(struct msc_iter *iter, struct msc *msc)
+{
+ /* already started, nothing to do */
+ if (iter->start_win)
+ return 0;
+
+ iter->start_win = msc_oldest_window(msc);
+ if (!iter->start_win)
+ return -EINVAL;
+
+ iter->win = iter->start_win;
+ iter->start_block = -1;
+
+ msc_iter_block_start(iter);
+
+ return 0;
+}
+
+static int msc_iter_win_advance(struct msc_iter *iter)
+{
+ iter->win = msc_next_window(iter->win);
+ iter->start_block = -1;
+
+ if (iter->win == iter->start_win) {
+ iter->eof++;
+ return 1;
+ }
+
+ msc_iter_block_start(iter);
+
+ return 0;
+}
+
+static int msc_iter_block_advance(struct msc_iter *iter)
+{
+ iter->block_off = 0;
+
+ /* wrapping */
+ if (iter->wrap_count && iter->block == iter->start_block) {
+ iter->wrap_count--;
+ if (!iter->wrap_count)
+ /* copied newest data from the wrapped block */
+ return msc_iter_win_advance(iter);
+ }
+
+ /* no wrapping, check for last written block */
+ if (!iter->wrap_count && msc_block_last_written(msc_iter_bdesc(iter)))
+ /* copied newest data for the window */
+ return msc_iter_win_advance(iter);
+
+ /* block advance */
+ if (++iter->block == iter->win->nr_blocks)
+ iter->block = 0;
+
+ /* no wrapping, sanity check in case there is no last written block */
+ if (!iter->wrap_count && iter->block == iter->start_block)
+ return msc_iter_win_advance(iter);
+
+ return 0;
+}
+
+/**
+ * msc_buffer_iterate() - go through multiblock buffer's data
+ * @iter: iterator structure
+ * @size: amount of data to scan
+ * @data: callback's private data
+ * @fn: iterator callback
+ *
+ * This will start at the window which will be written to next (containing
+ * the oldest data) and work its way to the current window, calling @fn
+ * for each chunk of data as it goes.
+ *
+ * Caller should have msc::user_count reference to make sure the buffer
+ * doesn't disappear from under us.
+ *
+ * Return: amount of data actually scanned.
+ */
+static ssize_t
+msc_buffer_iterate(struct msc_iter *iter, size_t size, void *data,
+ unsigned long (*fn)(void *, void *, size_t))
+{
+ struct msc *msc = iter->msc;
+ size_t len = size;
+ unsigned int advance;
+
+ if (iter->eof)
+ return 0;
+
+ /* start with the oldest window */
+ if (msc_iter_win_start(iter, msc))
+ return 0;
+
+ do {
+ unsigned long data_bytes = msc_data_sz(msc_iter_bdesc(iter));
+ void *src = (void *)msc_iter_bdesc(iter) + MSC_BDESC;
+ size_t tocopy = data_bytes, copied = 0;
+ size_t remaining = 0;
+
+ advance = 1;
+
+ /*
+ * If block wrapping happened, we need to visit the last block
+ * twice, because it contains both the oldest and the newest
+ * data in this window.
+ *
+ * First time (wrap_count==2), in the very beginning, to collect
+ * the oldest data, which is in the range
+ * (data_bytes..DATA_IN_PAGE).
+ *
+ * Second time (wrap_count==1), it's just like any other block,
+ * containing data in the range of [MSC_BDESC..data_bytes].
+ */
+ if (iter->block == iter->start_block && iter->wrap_count) {
+ tocopy = DATA_IN_PAGE - data_bytes;
+ src += data_bytes;
+ }
+
+ if (!tocopy)
+ goto next_block;
+
+ tocopy -= iter->block_off;
+ src += iter->block_off;
+
+ if (len < tocopy) {
+ tocopy = len;
+ advance = 0;
+ }
+
+ remaining = fn(data, src, tocopy);
+
+ if (remaining)
+ advance = 0;
+
+ copied = tocopy - remaining;
+ len -= copied;
+ iter->block_off += copied;
+ iter->offset += copied;
+
+ if (!advance)
+ break;
+
+next_block:
+ if (msc_iter_block_advance(iter))
+ break;
+
+ } while (len);
+
+ return size - len;
+}
+
+/**
+ * msc_buffer_clear_hw_header() - clear hw header for multiblock
+ * @msc: MSC device
+ */
+static void msc_buffer_clear_hw_header(struct msc *msc)
+{
+ struct msc_window *win;
+
+ mutex_lock(&msc->buf_mutex);
+ list_for_each_entry(win, &msc->win_list, entry) {
+ unsigned int blk;
+ size_t hw_sz = sizeof(struct msc_block_desc) -
+ offsetof(struct msc_block_desc, hw_tag);
+
+ for (blk = 0; blk < win->nr_blocks; blk++) {
+ struct msc_block_desc *bdesc = win->block[blk].bdesc;
+
+ memset(&bdesc->hw_tag, 0, hw_sz);
+ }
+ }
+ mutex_unlock(&msc->buf_mutex);
+}
+
+/**
+ * msc_configure() - set up MSC hardware
+ * @msc: the MSC device to configure
+ *
+ * Program storage mode, wrapping, burst length and trace buffer address
+ * into a given MSC. If msc::enabled is set, enable the trace, too.
+ */
+static int msc_configure(struct msc *msc)
+{
+ u32 reg;
+
+ if (msc->mode > MSC_MODE_MULTI)
+ return -ENOTSUPP;
+
+ if (msc->mode == MSC_MODE_MULTI)
+ msc_buffer_clear_hw_header(msc);
+
+ reg = msc->base_addr >> PAGE_SHIFT;
+ iowrite32(reg, msc->reg_base + REG_MSU_MSC0BAR);
+
+ if (msc->mode == MSC_MODE_SINGLE) {
+ reg = msc->nr_pages;
+ iowrite32(reg, msc->reg_base + REG_MSU_MSC0SIZE);
+ }
+
+ reg = ioread32(msc->reg_base + REG_MSU_MSC0CTL);
+ reg &= ~(MSC_MODE | MSC_WRAPEN | MSC_EN | MSC_RD_HDR_OVRD);
+
+ reg |= msc->mode << __ffs(MSC_MODE);
+ reg |= msc->burst_len << __ffs(MSC_LEN);
+ /*if (msc->mode == MSC_MODE_MULTI)
+ reg |= MSC_RD_HDR_OVRD; */
+ if (msc->wrap)
+ reg |= MSC_WRAPEN;
+ if (msc->enabled)
+ reg |= MSC_EN;
+
+ iowrite32(reg, msc->reg_base + REG_MSU_MSC0CTL);
+
+ if (msc->enabled) {
+ msc->thdev->output.multiblock = msc->mode == MSC_MODE_MULTI;
+ intel_th_trace_enable(msc->thdev);
+ }
+
+ return 0;
+}
+
+/**
+ * msc_disable() - disable MSC hardware
+ * @msc: MSC device to disable
+ *
+ * If @msc is enabled, disable tracing on the switch and then disable MSC
+ * storage.
+ */
+static void msc_disable(struct msc *msc)
+{
+ unsigned long count;
+ u32 reg;
+
+ if (!msc->enabled)
+ return;
+
+ intel_th_trace_disable(msc->thdev);
+
+ for (reg = 0, count = MSC_PLE_WAITLOOP_DEPTH;
+ count && !(reg & MSCSTS_PLE); count--) {
+ reg = ioread32(msc->reg_base + REG_MSU_MSC0STS);
+ cpu_relax();
+ }
+
+ if (!count)
+ dev_dbg(msc_dev(msc), "timeout waiting for MSC0 PLE\n");
+
+ if (msc->mode == MSC_MODE_SINGLE) {
+ msc->single_wrap = !!(reg & MSCSTS_WRAPSTAT);
+
+ reg = ioread32(msc->reg_base + REG_MSU_MSC0MWP);
+ msc->single_sz = reg & ((msc->nr_pages << PAGE_SHIFT) - 1);
+ dev_dbg(msc_dev(msc), "MSCnMWP: %08x/%08lx, wrap: %d\n",
+ reg, msc->single_sz, msc->single_wrap);
+ }
+
+ reg = ioread32(msc->reg_base + REG_MSU_MSC0CTL);
+ reg &= ~MSC_EN;
+ iowrite32(reg, msc->reg_base + REG_MSU_MSC0CTL);
+ msc->enabled = 0;
+
+ iowrite32(0, msc->reg_base + REG_MSU_MSC0BAR);
+ iowrite32(0, msc->reg_base + REG_MSU_MSC0SIZE);
+
+ dev_dbg(msc_dev(msc), "MSCnNWSA: %08x\n",
+ ioread32(msc->reg_base + REG_MSU_MSC0NWSA));
+
+ reg = ioread32(msc->reg_base + REG_MSU_MSC0STS);
+ dev_dbg(msc_dev(msc), "MSCnSTS: %08x\n", reg);
+}
+
+static int intel_th_msc_activate(struct intel_th_device *thdev)
+{
+ struct msc *msc = dev_get_drvdata(&thdev->dev);
+ int ret = 0;
+
+ if (!atomic_inc_unless_negative(&msc->user_count))
+ return -ENODEV;
+
+ mutex_lock(&msc->iter_mutex);
+ if (!list_empty(&msc->iter_list))
+ ret = -EBUSY;
+ mutex_unlock(&msc->iter_mutex);
+
+ if (ret) {
+ atomic_dec(&msc->user_count);
+ return ret;
+ }
+
+ msc->enabled = 1;
+
+ return msc_configure(msc);
+}
+
+static void intel_th_msc_deactivate(struct intel_th_device *thdev)
+{
+ struct msc *msc = dev_get_drvdata(&thdev->dev);
+
+ msc_disable(msc);
+
+ atomic_dec(&msc->user_count);
+}
+
+/**
+ * msc_buffer_contig_alloc() - allocate a contiguous buffer for SINGLE mode
+ * @msc: MSC device
+ * @size: allocation size in bytes
+ *
+ * This modifies msc::base, which requires msc::buf_mutex to serialize, so the
+ * caller is expected to hold it.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int msc_buffer_contig_alloc(struct msc *msc, unsigned long size)
+{
+ unsigned int order = get_order(size);
+ struct page *page;
+
+ if (!size)
+ return 0;
+
+ page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order);
+ if (!page)
+ return -ENOMEM;
+
+ split_page(page, order);
+ msc->nr_pages = size >> PAGE_SHIFT;
+ msc->base = page_address(page);
+ msc->base_addr = page_to_phys(page);
+
+ return 0;
+}
+
+/**
+ * msc_buffer_contig_free() - free a contiguous buffer
+ * @msc: MSC configured in SINGLE mode
+ */
+static void msc_buffer_contig_free(struct msc *msc)
+{
+ unsigned long off;
+
+ for (off = 0; off < msc->nr_pages << PAGE_SHIFT; off += PAGE_SIZE) {
+ struct page *page = virt_to_page(msc->base + off);
+
+ page->mapping = NULL;
+ __free_page(page);
+ }
+
+ msc->nr_pages = 0;
+}
+
+/**
+ * msc_buffer_contig_get_page() - find a page at a given offset
+ * @msc: MSC configured in SINGLE mode
+ * @pgoff: page offset
+ *
+ * Return: page, if @pgoff is within the range, NULL otherwise.
+ */
+static struct page *msc_buffer_contig_get_page(struct msc *msc,
+ unsigned long pgoff)
+{
+ if (pgoff >= msc->nr_pages)
+ return NULL;
+
+ return virt_to_page(msc->base + (pgoff << PAGE_SHIFT));
+}
+
+/**
+ * msc_buffer_win_alloc() - alloc a window for a multiblock mode
+ * @msc: MSC device
+ * @nr_blocks: number of pages in this window
+ *
+ * This modifies msc::win_list and msc::base, which requires msc::buf_mutex
+ * to serialize, so the caller is expected to hold it.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int msc_buffer_win_alloc(struct msc *msc, unsigned int nr_blocks)
+{
+ struct msc_window *win;
+ unsigned long size = PAGE_SIZE;
+ int i, ret = -ENOMEM;
+
+ if (!nr_blocks)
+ return 0;
+
+ win = kzalloc(offsetof(struct msc_window, block[nr_blocks]),
+ GFP_KERNEL);
+ if (!win)
+ return -ENOMEM;
+
+ if (!list_empty(&msc->win_list)) {
+ struct msc_window *prev = list_entry(msc->win_list.prev,
+ struct msc_window, entry);
+
+ win->pgoff = prev->pgoff + prev->nr_blocks;
+ }
+
+ for (i = 0; i < nr_blocks; i++) {
+ win->block[i].bdesc = dma_alloc_coherent(msc_dev(msc), size,
+ &win->block[i].addr,
+ GFP_KERNEL);
+
+#ifdef CONFIG_X86
+ /* Set the page as uncached */
+ set_memory_uc((unsigned long)win->block[i].bdesc, 1);
+#endif
+
+ if (!win->block[i].bdesc)
+ goto err_nomem;
+ }
+
+ win->msc = msc;
+ win->nr_blocks = nr_blocks;
+
+ if (list_empty(&msc->win_list)) {
+ msc->base = win->block[0].bdesc;
+ msc->base_addr = win->block[0].addr;
+ }
+
+ list_add_tail(&win->entry, &msc->win_list);
+ msc->nr_pages += nr_blocks;
+
+ return 0;
+
+err_nomem:
+ for (i--; i >= 0; i--) {
+#ifdef CONFIG_X86
+ /* Reset the page to write-back before releasing */
+ set_memory_wb((unsigned long)win->block[i].bdesc, 1);
+#endif
+ dma_free_coherent(msc_dev(msc), size, win->block[i].bdesc,
+ win->block[i].addr);
+ }
+ kfree(win);
+
+ return ret;
+}
+
+/**
+ * msc_buffer_win_free() - free a window from MSC's window list
+ * @msc: MSC device
+ * @win: window to free
+ *
+ * This modifies msc::win_list and msc::base, which requires msc::buf_mutex
+ * to serialize, so the caller is expected to hold it.
+ */
+static void msc_buffer_win_free(struct msc *msc, struct msc_window *win)
+{
+ int i;
+
+ msc->nr_pages -= win->nr_blocks;
+
+ list_del(&win->entry);
+ if (list_empty(&msc->win_list)) {
+ msc->base = NULL;
+ msc->base_addr = 0;
+ }
+
+ for (i = 0; i < win->nr_blocks; i++) {
+ struct page *page = virt_to_page(win->block[i].bdesc);
+
+ page->mapping = NULL;
+#ifdef CONFIG_X86
+ /* Reset the page to write-back before releasing */
+ set_memory_wb((unsigned long)win->block[i].bdesc, 1);
+#endif
+ dma_free_coherent(msc_dev(win->msc), PAGE_SIZE,
+ win->block[i].bdesc, win->block[i].addr);
+ }
+
+ kfree(win);
+}
+
+/**
+ * msc_buffer_relink() - set up block descriptors for multiblock mode
+ * @msc: MSC device
+ *
+ * This traverses msc::win_list, which requires msc::buf_mutex to serialize,
+ * so the caller is expected to hold it.
+ */
+static void msc_buffer_relink(struct msc *msc)
+{
+ struct msc_window *win, *next_win;
+
+ /* call with msc::mutex locked */
+ list_for_each_entry(win, &msc->win_list, entry) {
+ unsigned int blk;
+ u32 sw_tag = 0;
+
+ /*
+ * Last window's next_win should point to the first window
+ * and MSC_SW_TAG_LASTWIN should be set.
+ */
+ if (msc_is_last_win(win)) {
+ sw_tag |= MSC_SW_TAG_LASTWIN;
+ next_win = list_entry(msc->win_list.next,
+ struct msc_window, entry);
+ } else {
+ next_win = list_entry(win->entry.next,
+ struct msc_window, entry);
+ }
+
+ for (blk = 0; blk < win->nr_blocks; blk++) {
+ struct msc_block_desc *bdesc = win->block[blk].bdesc;
+
+ memset(bdesc, 0, sizeof(*bdesc));
+
+ bdesc->next_win = next_win->block[0].addr >> PAGE_SHIFT;
+
+ /*
+ * Similarly to last window, last block should point
+ * to the first one.
+ */
+ if (blk == win->nr_blocks - 1) {
+ sw_tag |= MSC_SW_TAG_LASTBLK;
+ bdesc->next_blk =
+ win->block[0].addr >> PAGE_SHIFT;
+ } else {
+ bdesc->next_blk =
+ win->block[blk + 1].addr >> PAGE_SHIFT;
+ }
+
+ bdesc->sw_tag = sw_tag;
+ bdesc->block_sz = PAGE_SIZE / 64;
+ }
+ }
+
+ /*
+ * Make the above writes globally visible before tracing is
+ * enabled to make sure hardware sees them coherently.
+ */
+ wmb();
+}
+
+static void msc_buffer_multi_free(struct msc *msc)
+{
+ struct msc_window *win, *iter;
+
+ list_for_each_entry_safe(win, iter, &msc->win_list, entry)
+ msc_buffer_win_free(msc, win);
+}
+
+static int msc_buffer_multi_alloc(struct msc *msc, unsigned long *nr_pages,
+ unsigned int nr_wins)
+{
+ int ret, i;
+
+ for (i = 0; i < nr_wins; i++) {
+ ret = msc_buffer_win_alloc(msc, nr_pages[i]);
+ if (ret) {
+ msc_buffer_multi_free(msc);
+ return ret;
+ }
+ }
+
+ msc_buffer_relink(msc);
+
+ return 0;
+}
+
+/**
+ * msc_buffer_free() - free buffers for MSC
+ * @msc: MSC device
+ *
+ * Free MSC's storage buffers.
+ *
+ * This modifies msc::win_list and msc::base, which requires msc::buf_mutex to
+ * serialize, so the caller is expected to hold it.
+ */
+static void msc_buffer_free(struct msc *msc)
+{
+ if (msc->mode == MSC_MODE_SINGLE)
+ msc_buffer_contig_free(msc);
+ else if (msc->mode == MSC_MODE_MULTI)
+ msc_buffer_multi_free(msc);
+}
+
+/**
+ * msc_buffer_alloc() - allocate a buffer for MSC
+ * @msc: MSC device
+ * @size: allocation size in bytes
+ *
+ * Allocate a storage buffer for MSC, depending on the msc::mode, it will be
+ * either done via msc_buffer_contig_alloc() for SINGLE operation mode or
+ * msc_buffer_win_alloc() for multiblock operation. The latter allocates one
+ * window per invocation, so in multiblock mode this can be called multiple
+ * times for the same MSC to allocate multiple windows.
+ *
+ * This modifies msc::win_list and msc::base, which requires msc::buf_mutex
+ * to serialize, so the caller is expected to hold it.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int msc_buffer_alloc(struct msc *msc, unsigned long *nr_pages,
+ unsigned int nr_wins)
+{
+ int ret;
+
+ /* -1: buffer not allocated */
+ if (atomic_read(&msc->user_count) != -1)
+ return -EBUSY;
+
+ if (msc->mode == MSC_MODE_SINGLE) {
+ if (nr_wins != 1)
+ return -EINVAL;
+
+ ret = msc_buffer_contig_alloc(msc, nr_pages[0] << PAGE_SHIFT);
+ } else if (msc->mode == MSC_MODE_MULTI) {
+ ret = msc_buffer_multi_alloc(msc, nr_pages, nr_wins);
+ } else {
+ ret = -ENOTSUPP;
+ }
+
+ if (!ret) {
+ /* allocation should be visible before the counter goes to 0 */
+ smp_mb__before_atomic();
+
+ if (WARN_ON_ONCE(atomic_cmpxchg(&msc->user_count, -1, 0) != -1))
+ return -EINVAL;
+ }
+
+ return ret;
+}
+
+/**
+ * msc_buffer_unlocked_free_unless_used() - free a buffer unless it's in use
+ * @msc: MSC device
+ *
+ * This will free MSC buffer unless it is in use or there is no allocated
+ * buffer.
+ * Caller needs to hold msc::buf_mutex.
+ *
+ * Return: 0 on successful deallocation or if there was no buffer to
+ * deallocate, -EBUSY if there are active users.
+ */
+static int msc_buffer_unlocked_free_unless_used(struct msc *msc)
+{
+ int count, ret = 0;
+
+ count = atomic_cmpxchg(&msc->user_count, 0, -1);
+
+ /* > 0: buffer is allocated and has users */
+ if (count > 0)
+ ret = -EBUSY;
+ /* 0: buffer is allocated, no users */
+ else if (!count)
+ msc_buffer_free(msc);
+ /* < 0: no buffer, nothing to do */
+
+ return ret;
+}
+
+/**
+ * msc_buffer_free_unless_used() - free a buffer unless it's in use
+ * @msc: MSC device
+ *
+ * This is a locked version of msc_buffer_unlocked_free_unless_used().
+ */
+static int msc_buffer_free_unless_used(struct msc *msc)
+{
+ int ret;
+
+ mutex_lock(&msc->buf_mutex);
+ ret = msc_buffer_unlocked_free_unless_used(msc);
+ mutex_unlock(&msc->buf_mutex);
+
+ return ret;
+}
+
+/**
+ * msc_buffer_get_page() - get MSC buffer page at a given offset
+ * @msc: MSC device
+ * @pgoff: page offset into the storage buffer
+ *
+ * This traverses msc::win_list, so holding msc::buf_mutex is expected from
+ * the caller.
+ *
+ * Return: page if @pgoff corresponds to a valid buffer page or NULL.
+ */
+static struct page *msc_buffer_get_page(struct msc *msc, unsigned long pgoff)
+{
+ struct msc_window *win;
+
+ if (msc->mode == MSC_MODE_SINGLE)
+ return msc_buffer_contig_get_page(msc, pgoff);
+
+ list_for_each_entry(win, &msc->win_list, entry)
+ if (pgoff >= win->pgoff && pgoff < win->pgoff + win->nr_blocks)
+ goto found;
+
+ return NULL;
+
+found:
+ pgoff -= win->pgoff;
+ return virt_to_page(win->block[pgoff].bdesc);
+}
+
+/**
+ * struct msc_win_to_user_struct - data for copy_to_user() callback
+ * @buf: userspace buffer to copy data to
+ * @offset: running offset
+ */
+struct msc_win_to_user_struct {
+ char __user *buf;
+ unsigned long offset;
+};
+
+/**
+ * msc_win_to_user() - iterator for msc_buffer_iterate() to copy data to user
+ * @data: callback's private data
+ * @src: source buffer
+ * @len: amount of data to copy from the source buffer
+ */
+static unsigned long msc_win_to_user(void *data, void *src, size_t len)
+{
+ struct msc_win_to_user_struct *u = data;
+ unsigned long ret;
+
+ ret = copy_to_user(u->buf + u->offset, src, len);
+ u->offset += len - ret;
+
+ return ret;
+}
+
+
+/*
+ * file operations' callbacks
+ */
+
+static int intel_th_msc_open(struct inode *inode, struct file *file)
+{
+ struct intel_th_device *thdev = file->private_data;
+ struct msc *msc = dev_get_drvdata(&thdev->dev);
+ struct msc_iter *iter;
+
+ if (!capable(CAP_SYS_RAWIO))
+ return -EPERM;
+
+ iter = msc_iter_install(msc);
+ if (!iter)
+ return -ENOMEM;
+
+ file->private_data = iter;
+
+ return nonseekable_open(inode, file);
+}
+
+static int intel_th_msc_release(struct inode *inode, struct file *file)
+{
+ struct msc_iter *iter = file->private_data;
+ struct msc *msc = iter->msc;
+
+ msc_iter_remove(iter, msc);
+
+ return 0;
+}
+
+static ssize_t
+msc_single_to_user(struct msc *msc, char __user *buf, loff_t off, size_t len)
+{
+ unsigned long size = msc->nr_pages << PAGE_SHIFT, rem = len;
+ unsigned long start = off, tocopy = 0;
+
+ if (msc->single_wrap) {
+ start += msc->single_sz;
+ if (start < size) {
+ tocopy = min(rem, size - start);
+ if (copy_to_user(buf, msc->base + start, tocopy))
+ return -EFAULT;
+
+ buf += tocopy;
+ rem -= tocopy;
+ start += tocopy;
+ }
+
+ start &= size - 1;
+ if (rem) {
+ tocopy = min(rem, msc->single_sz - start);
+ if (copy_to_user(buf, msc->base + start, tocopy))
+ return -EFAULT;
+
+ rem -= tocopy;
+ }
+
+ return len - rem;
+ }
+
+ if (copy_to_user(buf, msc->base + start, rem))
+ return -EFAULT;
+
+ return len;
+}
+
+static ssize_t intel_th_msc_read(struct file *file, char __user *buf,
+ size_t len, loff_t *ppos)
+{
+ struct msc_iter *iter = file->private_data;
+ struct msc *msc = iter->msc;
+ size_t size;
+ loff_t off = *ppos;
+ ssize_t ret = 0;
+
+ if (!atomic_inc_unless_negative(&msc->user_count))
+ return 0;
+
+ if (msc->enabled) {
+ ret = -EBUSY;
+ goto put_count;
+ }
+
+ if (msc->mode == MSC_MODE_SINGLE && !msc->single_wrap)
+ size = msc->single_sz;
+ else
+ size = msc->nr_pages << PAGE_SHIFT;
+
+ if (!size)
+ return 0;
+
+ if (off >= size) {
+ len = 0;
+ goto put_count;
+ }
+ if (off + len >= size)
+ len = size - off;
+
+ if (msc->mode == MSC_MODE_SINGLE) {
+ ret = msc_single_to_user(msc, buf, off, len);
+ if (ret >= 0)
+ *ppos += ret;
+ } else if (msc->mode == MSC_MODE_MULTI) {
+ struct msc_win_to_user_struct u = {
+ .buf = buf,
+ .offset = 0,
+ };
+
+ ret = msc_buffer_iterate(iter, len, &u, msc_win_to_user);
+ if (ret >= 0)
+ *ppos = iter->offset;
+ } else {
+ ret = -ENOTSUPP;
+ }
+
+put_count:
+ atomic_dec(&msc->user_count);
+
+ return ret;
+}
+
+/*
+ * vm operations callbacks (vm_ops)
+ */
+
+static void msc_mmap_open(struct vm_area_struct *vma)
+{
+ struct msc_iter *iter = vma->vm_file->private_data;
+ struct msc *msc = iter->msc;
+
+ atomic_inc(&msc->mmap_count);
+}
+
+static void msc_mmap_close(struct vm_area_struct *vma)
+{
+ struct msc_iter *iter = vma->vm_file->private_data;
+ struct msc *msc = iter->msc;
+ unsigned long pg;
+
+ if (!atomic_dec_and_mutex_lock(&msc->mmap_count, &msc->buf_mutex))
+ return;
+
+ /* drop page _counts */
+ for (pg = 0; pg < msc->nr_pages; pg++) {
+ struct page *page = msc_buffer_get_page(msc, pg);
+
+ if (WARN_ON_ONCE(!page))
+ continue;
+
+ if (page->mapping)
+ page->mapping = NULL;
+ }
+
+ /* last mapping -- drop user_count */
+ atomic_dec(&msc->user_count);
+ mutex_unlock(&msc->buf_mutex);
+}
+
+static int msc_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct msc_iter *iter = vma->vm_file->private_data;
+ struct msc *msc = iter->msc;
+
+ vmf->page = msc_buffer_get_page(msc, vmf->pgoff);
+ if (!vmf->page)
+ return VM_FAULT_SIGBUS;
+
+ get_page(vmf->page);
+ vmf->page->mapping = vma->vm_file->f_mapping;
+ vmf->page->index = vmf->pgoff;
+
+ return 0;
+}
+
+static const struct vm_operations_struct msc_mmap_ops = {
+ .open = msc_mmap_open,
+ .close = msc_mmap_close,
+ .fault = msc_mmap_fault,
+};
+
+static int intel_th_msc_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ unsigned long size = vma->vm_end - vma->vm_start;
+ struct msc_iter *iter = vma->vm_file->private_data;
+ struct msc *msc = iter->msc;
+ int ret = -EINVAL;
+
+ if (!size || offset_in_page(size))
+ return -EINVAL;
+
+ if (vma->vm_pgoff)
+ return -EINVAL;
+
+ /* grab user_count once per mmap; drop in msc_mmap_close() */
+ if (!atomic_inc_unless_negative(&msc->user_count))
+ return -EINVAL;
+
+ if (msc->mode != MSC_MODE_SINGLE &&
+ msc->mode != MSC_MODE_MULTI)
+ goto out;
+
+ if (size >> PAGE_SHIFT != msc->nr_pages)
+ goto out;
+
+ atomic_set(&msc->mmap_count, 1);
+ ret = 0;
+
+out:
+ if (ret)
+ atomic_dec(&msc->user_count);
+
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ vma->vm_flags |= VM_DONTEXPAND | VM_DONTCOPY;
+ vma->vm_ops = &msc_mmap_ops;
+ return ret;
+}
+
+static const struct file_operations intel_th_msc_fops = {
+ .open = intel_th_msc_open,
+ .release = intel_th_msc_release,
+ .read = intel_th_msc_read,
+ .mmap = intel_th_msc_mmap,
+ .llseek = no_llseek,
+};
+
+static int intel_th_msc_init(struct msc *msc)
+{
+ atomic_set(&msc->user_count, -1);
+
+ msc->mode = MSC_MODE_MULTI;
+ mutex_init(&msc->buf_mutex);
+ INIT_LIST_HEAD(&msc->win_list);
+
+ mutex_init(&msc->iter_mutex);
+ INIT_LIST_HEAD(&msc->iter_list);
+
+ msc->burst_len =
+ (ioread32(msc->reg_base + REG_MSU_MSC0CTL) & MSC_LEN) >>
+ __ffs(MSC_LEN);
+
+ return 0;
+}
+
+static const char * const msc_mode[] = {
+ [MSC_MODE_SINGLE] = "single",
+ [MSC_MODE_MULTI] = "multi",
+ [MSC_MODE_EXI] = "ExI",
+ [MSC_MODE_DEBUG] = "debug",
+};
+
+static ssize_t
+wrap_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct msc *msc = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", msc->wrap);
+}
+
+static ssize_t
+wrap_store(struct device *dev, struct device_attribute *attr, const char *buf,
+ size_t size)
+{
+ struct msc *msc = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ msc->wrap = !!val;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(wrap);
+
+static ssize_t
+mode_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct msc *msc = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%s\n", msc_mode[msc->mode]);
+}
+
+static ssize_t
+mode_store(struct device *dev, struct device_attribute *attr, const char *buf,
+ size_t size)
+{
+ struct msc *msc = dev_get_drvdata(dev);
+ size_t len = size;
+ char *cp;
+ int i, ret;
+
+ if (!capable(CAP_SYS_RAWIO))
+ return -EPERM;
+
+ cp = memchr(buf, '\n', len);
+ if (cp)
+ len = cp - buf;
+
+ for (i = 0; i < ARRAY_SIZE(msc_mode); i++)
+ if (!strncmp(msc_mode[i], buf, len))
+ goto found;
+
+ return -EINVAL;
+
+found:
+ mutex_lock(&msc->buf_mutex);
+ ret = msc_buffer_unlocked_free_unless_used(msc);
+ if (!ret)
+ msc->mode = i;
+ mutex_unlock(&msc->buf_mutex);
+
+ return ret ? ret : size;
+}
+
+static DEVICE_ATTR_RW(mode);
+
+static ssize_t
+nr_pages_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+ struct msc *msc = dev_get_drvdata(dev);
+ struct msc_window *win;
+ size_t count = 0;
+
+ mutex_lock(&msc->buf_mutex);
+
+ if (msc->mode == MSC_MODE_SINGLE)
+ count = scnprintf(buf, PAGE_SIZE, "%ld\n", msc->nr_pages);
+ else if (msc->mode == MSC_MODE_MULTI) {
+ list_for_each_entry(win, &msc->win_list, entry) {
+ count += scnprintf(buf + count, PAGE_SIZE - count,
+ "%d%c", win->nr_blocks,
+ msc_is_last_win(win) ? '\n' : ',');
+ }
+ } else {
+ count = scnprintf(buf, PAGE_SIZE, "unsupported\n");
+ }
+
+ mutex_unlock(&msc->buf_mutex);
+
+ return count;
+}
+
+static ssize_t
+nr_pages_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct msc *msc = dev_get_drvdata(dev);
+ unsigned long val, *win = NULL, *rewin;
+ size_t len = size;
+ const char *p = buf;
+ char *end, *s;
+ int ret, nr_wins = 0;
+
+ if (!capable(CAP_SYS_RAWIO))
+ return -EPERM;
+
+ ret = msc_buffer_free_unless_used(msc);
+ if (ret)
+ return ret;
+
+ /* scan the comma-separated list of allocation sizes */
+ end = memchr(buf, '\n', len);
+ if (end)
+ len = end - buf;
+
+ do {
+ end = memchr(p, ',', len);
+ s = kstrndup(p, end ? end - p : len, GFP_KERNEL);
+ ret = kstrtoul(s, 10, &val);
+ kfree(s);
+
+ if (ret || !val)
+ goto free_win;
+
+ if (nr_wins && msc->mode == MSC_MODE_SINGLE) {
+ ret = -EINVAL;
+ goto free_win;
+ }
+
+ nr_wins++;
+ rewin = krealloc(win, sizeof(*win) * nr_wins, GFP_KERNEL);
+ if (!rewin) {
+ kfree(win);
+ return -ENOMEM;
+ }
+
+ win = rewin;
+ win[nr_wins - 1] = val;
+
+ if (!end)
+ break;
+
+ len -= end - p;
+ p = end + 1;
+ } while (len);
+
+ mutex_lock(&msc->buf_mutex);
+ ret = msc_buffer_alloc(msc, win, nr_wins);
+ mutex_unlock(&msc->buf_mutex);
+
+free_win:
+ kfree(win);
+
+ return ret ? ret : size;
+}
+
+static DEVICE_ATTR_RW(nr_pages);
+
+static struct attribute *msc_output_attrs[] = {
+ &dev_attr_wrap.attr,
+ &dev_attr_mode.attr,
+ &dev_attr_nr_pages.attr,
+ NULL,
+};
+
+static struct attribute_group msc_output_group = {
+ .attrs = msc_output_attrs,
+};
+
+static int intel_th_msc_probe(struct intel_th_device *thdev)
+{
+ struct device *dev = &thdev->dev;
+ struct resource *res;
+ struct msc *msc;
+ void __iomem *base;
+ int err;
+
+ res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ msc = devm_kzalloc(dev, sizeof(*msc), GFP_KERNEL);
+ if (!msc)
+ return -ENOMEM;
+
+ msc->index = thdev->id;
+
+ msc->thdev = thdev;
+ msc->reg_base = base + msc->index * 0x100;
+
+ err = intel_th_msc_init(msc);
+ if (err)
+ return err;
+
+ err = sysfs_create_group(&dev->kobj, &msc_output_group);
+ if (err)
+ return err;
+
+ dev_set_drvdata(dev, msc);
+
+ return 0;
+}
+
+static void intel_th_msc_remove(struct intel_th_device *thdev)
+{
+ sysfs_remove_group(&thdev->dev.kobj, &msc_output_group);
+}
+
+static struct intel_th_driver intel_th_msc_driver = {
+ .probe = intel_th_msc_probe,
+ .remove = intel_th_msc_remove,
+ .activate = intel_th_msc_activate,
+ .deactivate = intel_th_msc_deactivate,
+ .fops = &intel_th_msc_fops,
+ .driver = {
+ .name = "msc",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_driver(intel_th_msc_driver,
+ intel_th_driver_register,
+ intel_th_driver_unregister);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub Memory Storage Unit driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/intel_th/msu.h b/drivers/hwtracing/intel_th/msu.h
new file mode 100644
index 000000000000..9b710e4aa98a
--- /dev/null
+++ b/drivers/hwtracing/intel_th/msu.h
@@ -0,0 +1,116 @@
+/*
+ * Intel(R) Trace Hub Memory Storage Unit (MSU) data structures
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __INTEL_TH_MSU_H__
+#define __INTEL_TH_MSU_H__
+
+enum {
+ REG_MSU_MSUPARAMS = 0x0000,
+ REG_MSU_MSUSTS = 0x0008,
+ REG_MSU_MSC0CTL = 0x0100, /* MSC0 control */
+ REG_MSU_MSC0STS = 0x0104, /* MSC0 status */
+ REG_MSU_MSC0BAR = 0x0108, /* MSC0 output base address */
+ REG_MSU_MSC0SIZE = 0x010c, /* MSC0 output size */
+ REG_MSU_MSC0MWP = 0x0110, /* MSC0 write pointer */
+ REG_MSU_MSC0NWSA = 0x011c, /* MSC0 next window start address */
+
+ REG_MSU_MSC1CTL = 0x0200, /* MSC1 control */
+ REG_MSU_MSC1STS = 0x0204, /* MSC1 status */
+ REG_MSU_MSC1BAR = 0x0208, /* MSC1 output base address */
+ REG_MSU_MSC1SIZE = 0x020c, /* MSC1 output size */
+ REG_MSU_MSC1MWP = 0x0210, /* MSC1 write pointer */
+ REG_MSU_MSC1NWSA = 0x021c, /* MSC1 next window start address */
+};
+
+/* MSUSTS bits */
+#define MSUSTS_MSU_INT BIT(0)
+
+/* MSCnCTL bits */
+#define MSC_EN BIT(0)
+#define MSC_WRAPEN BIT(1)
+#define MSC_RD_HDR_OVRD BIT(2)
+#define MSC_MODE (BIT(4) | BIT(5))
+#define MSC_LEN (BIT(8) | BIT(9) | BIT(10))
+
+/* MSC operating modes (MSC_MODE) */
+enum {
+ MSC_MODE_SINGLE = 0,
+ MSC_MODE_MULTI,
+ MSC_MODE_EXI,
+ MSC_MODE_DEBUG,
+};
+
+/* MSCnSTS bits */
+#define MSCSTS_WRAPSTAT BIT(1) /* Wrap occurred */
+#define MSCSTS_PLE BIT(2) /* Pipeline Empty */
+
+/*
+ * Multiblock/multiwindow block descriptor
+ */
+struct msc_block_desc {
+ u32 sw_tag;
+ u32 block_sz;
+ u32 next_blk;
+ u32 next_win;
+ u32 res0[4];
+ u32 hw_tag;
+ u32 valid_dw;
+ u32 ts_low;
+ u32 ts_high;
+ u32 res1[4];
+} __packed;
+
+#define MSC_BDESC sizeof(struct msc_block_desc)
+#define DATA_IN_PAGE (PAGE_SIZE - MSC_BDESC)
+
+/* MSC multiblock sw tag bits */
+#define MSC_SW_TAG_LASTBLK BIT(0)
+#define MSC_SW_TAG_LASTWIN BIT(1)
+
+/* MSC multiblock hw tag bits */
+#define MSC_HW_TAG_TRIGGER BIT(0)
+#define MSC_HW_TAG_BLOCKWRAP BIT(1)
+#define MSC_HW_TAG_WINWRAP BIT(2)
+#define MSC_HW_TAG_ENDBIT BIT(3)
+
+static inline unsigned long msc_data_sz(struct msc_block_desc *bdesc)
+{
+ if (!bdesc->valid_dw)
+ return 0;
+
+ return bdesc->valid_dw * 4 - MSC_BDESC;
+}
+
+static inline bool msc_block_wrapped(struct msc_block_desc *bdesc)
+{
+ if (bdesc->hw_tag & MSC_HW_TAG_BLOCKWRAP)
+ return true;
+
+ return false;
+}
+
+static inline bool msc_block_last_written(struct msc_block_desc *bdesc)
+{
+ if ((bdesc->hw_tag & MSC_HW_TAG_ENDBIT) ||
+ (msc_data_sz(bdesc) != DATA_IN_PAGE))
+ return true;
+
+ return false;
+}
+
+/* waiting for Pipeline Empty bit(s) to assert for MSC */
+#define MSC_PLE_WAITLOOP_DEPTH 10000
+
+#endif /* __INTEL_TH_MSU_H__ */
diff --git a/drivers/hwtracing/intel_th/pci.c b/drivers/hwtracing/intel_th/pci.c
new file mode 100644
index 000000000000..641e87936064
--- /dev/null
+++ b/drivers/hwtracing/intel_th/pci.c
@@ -0,0 +1,86 @@
+/*
+ * Intel(R) Trace Hub pci driver
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/sysfs.h>
+#include <linux/pci.h>
+
+#include "intel_th.h"
+
+#define DRIVER_NAME "intel_th_pci"
+
+#define BAR_MASK (BIT(TH_MMIO_CONFIG) | BIT(TH_MMIO_SW))
+
+static int intel_th_pci_probe(struct pci_dev *pdev,
+ const struct pci_device_id *id)
+{
+ struct intel_th *th;
+ int err;
+
+ err = pcim_enable_device(pdev);
+ if (err)
+ return err;
+
+ err = pcim_iomap_regions_request_all(pdev, BAR_MASK, DRIVER_NAME);
+ if (err)
+ return err;
+
+ th = intel_th_alloc(&pdev->dev, pdev->resource,
+ DEVICE_COUNT_RESOURCE, pdev->irq);
+ if (IS_ERR(th))
+ return PTR_ERR(th);
+
+ pci_set_drvdata(pdev, th);
+
+ return 0;
+}
+
+static void intel_th_pci_remove(struct pci_dev *pdev)
+{
+ struct intel_th *th = pci_get_drvdata(pdev);
+
+ intel_th_free(th);
+}
+
+static const struct pci_device_id intel_th_pci_id_table[] = {
+ {
+ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x9d26),
+ .driver_data = (kernel_ulong_t)0,
+ },
+ {
+ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0xa126),
+ .driver_data = (kernel_ulong_t)0,
+ },
+ { 0 },
+};
+
+MODULE_DEVICE_TABLE(pci, intel_th_pci_id_table);
+
+static struct pci_driver intel_th_pci_driver = {
+ .name = DRIVER_NAME,
+ .id_table = intel_th_pci_id_table,
+ .probe = intel_th_pci_probe,
+ .remove = intel_th_pci_remove,
+};
+
+module_pci_driver(intel_th_pci_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub PCI controller driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@intel.com>");
diff --git a/drivers/hwtracing/intel_th/pti.c b/drivers/hwtracing/intel_th/pti.c
new file mode 100644
index 000000000000..57cbfdcc7ef0
--- /dev/null
+++ b/drivers/hwtracing/intel_th/pti.c
@@ -0,0 +1,252 @@
+/*
+ * Intel(R) Trace Hub PTI output driver
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/sizes.h>
+#include <linux/printk.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/io.h>
+
+#include "intel_th.h"
+#include "pti.h"
+
+struct pti_device {
+ void __iomem *base;
+ struct intel_th_device *thdev;
+ unsigned int mode;
+ unsigned int freeclk;
+ unsigned int clkdiv;
+ unsigned int patgen;
+};
+
+/* map PTI widths to MODE settings of PTI_CTL register */
+static const unsigned int pti_mode[] = {
+ 0, 4, 8, 0, 12, 0, 0, 0, 16, 0, 0, 0, 0, 0, 0, 0,
+};
+
+static int pti_width_mode(unsigned int width)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(pti_mode); i++)
+ if (pti_mode[i] == width)
+ return i;
+
+ return -EINVAL;
+}
+
+static ssize_t mode_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", pti_mode[pti->mode]);
+}
+
+static ssize_t mode_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ ret = pti_width_mode(val);
+ if (ret < 0)
+ return ret;
+
+ pti->mode = ret;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(mode);
+
+static ssize_t
+freerunning_clock_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", pti->freeclk);
+}
+
+static ssize_t
+freerunning_clock_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ pti->freeclk = !!val;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(freerunning_clock);
+
+static ssize_t
+clock_divider_show(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%d\n", 1u << pti->clkdiv);
+}
+
+static ssize_t
+clock_divider_store(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ struct pti_device *pti = dev_get_drvdata(dev);
+ unsigned long val;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ if (!is_power_of_2(val) || val > 8 || !val)
+ return -EINVAL;
+
+ pti->clkdiv = val;
+
+ return size;
+}
+
+static DEVICE_ATTR_RW(clock_divider);
+
+static struct attribute *pti_output_attrs[] = {
+ &dev_attr_mode.attr,
+ &dev_attr_freerunning_clock.attr,
+ &dev_attr_clock_divider.attr,
+ NULL,
+};
+
+static struct attribute_group pti_output_group = {
+ .attrs = pti_output_attrs,
+};
+
+static int intel_th_pti_activate(struct intel_th_device *thdev)
+{
+ struct pti_device *pti = dev_get_drvdata(&thdev->dev);
+ u32 ctl = PTI_EN;
+
+ if (pti->patgen)
+ ctl |= pti->patgen << __ffs(PTI_PATGENMODE);
+ if (pti->freeclk)
+ ctl |= PTI_FCEN;
+ ctl |= pti->mode << __ffs(PTI_MODE);
+ ctl |= pti->clkdiv << __ffs(PTI_CLKDIV);
+
+ iowrite32(ctl, pti->base + REG_PTI_CTL);
+
+ intel_th_trace_enable(thdev);
+
+ return 0;
+}
+
+static void intel_th_pti_deactivate(struct intel_th_device *thdev)
+{
+ struct pti_device *pti = dev_get_drvdata(&thdev->dev);
+
+ intel_th_trace_disable(thdev);
+
+ iowrite32(0, pti->base + REG_PTI_CTL);
+}
+
+static void read_hw_config(struct pti_device *pti)
+{
+ u32 ctl = ioread32(pti->base + REG_PTI_CTL);
+
+ pti->mode = (ctl & PTI_MODE) >> __ffs(PTI_MODE);
+ pti->clkdiv = (ctl & PTI_CLKDIV) >> __ffs(PTI_CLKDIV);
+ pti->freeclk = !!(ctl & PTI_FCEN);
+
+ if (!pti_mode[pti->mode])
+ pti->mode = pti_width_mode(4);
+ if (!pti->clkdiv)
+ pti->clkdiv = 1;
+}
+
+static int intel_th_pti_probe(struct intel_th_device *thdev)
+{
+ struct device *dev = &thdev->dev;
+ struct resource *res;
+ struct pti_device *pti;
+ void __iomem *base;
+ int ret;
+
+ res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ pti = devm_kzalloc(dev, sizeof(*pti), GFP_KERNEL);
+ if (!pti)
+ return -ENOMEM;
+
+ pti->thdev = thdev;
+ pti->base = base;
+
+ read_hw_config(pti);
+
+ ret = sysfs_create_group(&dev->kobj, &pti_output_group);
+ if (ret)
+ return ret;
+
+ dev_set_drvdata(dev, pti);
+
+ return 0;
+}
+
+static void intel_th_pti_remove(struct intel_th_device *thdev)
+{
+}
+
+static struct intel_th_driver intel_th_pti_driver = {
+ .probe = intel_th_pti_probe,
+ .remove = intel_th_pti_remove,
+ .activate = intel_th_pti_activate,
+ .deactivate = intel_th_pti_deactivate,
+ .driver = {
+ .name = "pti",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_driver(intel_th_pti_driver,
+ intel_th_driver_register,
+ intel_th_driver_unregister);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub PTI output driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/intel_th/pti.h b/drivers/hwtracing/intel_th/pti.h
new file mode 100644
index 000000000000..20883f5628cf
--- /dev/null
+++ b/drivers/hwtracing/intel_th/pti.h
@@ -0,0 +1,29 @@
+/*
+ * Intel(R) Trace Hub PTI output data structures
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __INTEL_TH_STH_H__
+#define __INTEL_TH_STH_H__
+
+enum {
+ REG_PTI_CTL = 0x1c00,
+};
+
+#define PTI_EN BIT(0)
+#define PTI_FCEN BIT(1)
+#define PTI_MODE 0xf0
+#define PTI_CLKDIV 0x000f0000
+#define PTI_PATGENMODE 0x00f00000
+
+#endif /* __INTEL_TH_STH_H__ */
diff --git a/drivers/hwtracing/intel_th/sth.c b/drivers/hwtracing/intel_th/sth.c
new file mode 100644
index 000000000000..56101c33e10f
--- /dev/null
+++ b/drivers/hwtracing/intel_th/sth.c
@@ -0,0 +1,259 @@
+/*
+ * Intel(R) Trace Hub Software Trace Hub support
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/stm.h>
+
+#include "intel_th.h"
+#include "sth.h"
+
+struct sth_device {
+ void __iomem *base;
+ void __iomem *channels;
+ phys_addr_t channels_phys;
+ struct device *dev;
+ struct stm_data stm;
+ unsigned int sw_nmasters;
+};
+
+static struct intel_th_channel __iomem *
+sth_channel(struct sth_device *sth, unsigned int master, unsigned int channel)
+{
+ struct intel_th_channel __iomem *sw_map = sth->channels;
+
+ return &sw_map[(master - sth->stm.sw_start) * sth->stm.sw_nchannels +
+ channel];
+}
+
+static void sth_iowrite(void __iomem *dest, const unsigned char *payload,
+ unsigned int size)
+{
+ switch (size) {
+#ifdef CONFIG_64BIT
+ case 8:
+ writeq_relaxed(*(u64 *)payload, dest);
+ break;
+#endif
+ case 4:
+ writel_relaxed(*(u32 *)payload, dest);
+ break;
+ case 2:
+ writew_relaxed(*(u16 *)payload, dest);
+ break;
+ case 1:
+ writeb_relaxed(*(u8 *)payload, dest);
+ break;
+ default:
+ break;
+ }
+}
+
+static ssize_t sth_stm_packet(struct stm_data *stm_data, unsigned int master,
+ unsigned int channel, unsigned int packet,
+ unsigned int flags, unsigned int size,
+ const unsigned char *payload)
+{
+ struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
+ struct intel_th_channel __iomem *out =
+ sth_channel(sth, master, channel);
+ u64 __iomem *outp = &out->Dn;
+ unsigned long reg = REG_STH_TRIG;
+
+#ifndef CONFIG_64BIT
+ if (size > 4)
+ size = 4;
+#endif
+
+ size = rounddown_pow_of_two(size);
+
+ switch (packet) {
+ /* Global packets (GERR, XSYNC, TRIG) are sent with register writes */
+ case STP_PACKET_GERR:
+ reg += 4;
+ case STP_PACKET_XSYNC:
+ reg += 8;
+ case STP_PACKET_TRIG:
+ if (flags & STP_PACKET_TIMESTAMPED)
+ reg += 4;
+ iowrite8(*payload, sth->base + reg);
+ break;
+
+ case STP_PACKET_MERR:
+ sth_iowrite(&out->MERR, payload, size);
+ break;
+
+ case STP_PACKET_FLAG:
+ if (flags & STP_PACKET_TIMESTAMPED)
+ outp = (u64 __iomem *)&out->FLAG_TS;
+ else
+ outp = (u64 __iomem *)&out->FLAG;
+
+ size = 1;
+ sth_iowrite(outp, payload, size);
+ break;
+
+ case STP_PACKET_USER:
+ if (flags & STP_PACKET_TIMESTAMPED)
+ outp = &out->USER_TS;
+ else
+ outp = &out->USER;
+ sth_iowrite(outp, payload, size);
+ break;
+
+ case STP_PACKET_DATA:
+ outp = &out->Dn;
+
+ if (flags & STP_PACKET_TIMESTAMPED)
+ outp += 2;
+ if (flags & STP_PACKET_MARKED)
+ outp++;
+
+ sth_iowrite(outp, payload, size);
+ break;
+ }
+
+ return size;
+}
+
+static phys_addr_t
+sth_stm_mmio_addr(struct stm_data *stm_data, unsigned int master,
+ unsigned int channel, unsigned int nr_chans)
+{
+ struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
+ phys_addr_t addr;
+
+ master -= sth->stm.sw_start;
+ addr = sth->channels_phys + (master * sth->stm.sw_nchannels + channel) *
+ sizeof(struct intel_th_channel);
+
+ if (offset_in_page(addr) ||
+ offset_in_page(nr_chans * sizeof(struct intel_th_channel)))
+ return 0;
+
+ return addr;
+}
+
+static int sth_stm_link(struct stm_data *stm_data, unsigned int master,
+ unsigned int channel)
+{
+ struct sth_device *sth = container_of(stm_data, struct sth_device, stm);
+
+ intel_th_set_output(to_intel_th_device(sth->dev), master);
+
+ return 0;
+}
+
+static int intel_th_sw_init(struct sth_device *sth)
+{
+ u32 reg;
+
+ reg = ioread32(sth->base + REG_STH_STHCAP1);
+ sth->stm.sw_nchannels = reg & 0xff;
+
+ reg = ioread32(sth->base + REG_STH_STHCAP0);
+ sth->stm.sw_start = reg & 0xffff;
+ sth->stm.sw_end = reg >> 16;
+
+ sth->sw_nmasters = sth->stm.sw_end - sth->stm.sw_start;
+ dev_dbg(sth->dev, "sw_start: %x sw_end: %x masters: %x nchannels: %x\n",
+ sth->stm.sw_start, sth->stm.sw_end, sth->sw_nmasters,
+ sth->stm.sw_nchannels);
+
+ return 0;
+}
+
+static int intel_th_sth_probe(struct intel_th_device *thdev)
+{
+ struct device *dev = &thdev->dev;
+ struct sth_device *sth;
+ struct resource *res;
+ void __iomem *base, *channels;
+ int err;
+
+ res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ base = devm_ioremap(dev, res->start, resource_size(res));
+ if (!base)
+ return -ENOMEM;
+
+ res = intel_th_device_get_resource(thdev, IORESOURCE_MEM, 1);
+ if (!res)
+ return -ENODEV;
+
+ channels = devm_ioremap(dev, res->start, resource_size(res));
+ if (!channels)
+ return -ENOMEM;
+
+ sth = devm_kzalloc(dev, sizeof(*sth), GFP_KERNEL);
+ if (!sth)
+ return -ENOMEM;
+
+ sth->dev = dev;
+ sth->base = base;
+ sth->channels = channels;
+ sth->channels_phys = res->start;
+ sth->stm.name = dev_name(dev);
+ sth->stm.packet = sth_stm_packet;
+ sth->stm.mmio_addr = sth_stm_mmio_addr;
+ sth->stm.sw_mmiosz = sizeof(struct intel_th_channel);
+ sth->stm.link = sth_stm_link;
+
+ err = intel_th_sw_init(sth);
+ if (err)
+ return err;
+
+ err = stm_register_device(dev, &sth->stm, THIS_MODULE);
+ if (err) {
+ dev_err(dev, "stm_register_device failed\n");
+ return err;
+ }
+
+ dev_set_drvdata(dev, sth);
+
+ return 0;
+}
+
+static void intel_th_sth_remove(struct intel_th_device *thdev)
+{
+ struct sth_device *sth = dev_get_drvdata(&thdev->dev);
+
+ stm_unregister_device(&sth->stm);
+}
+
+static struct intel_th_driver intel_th_sth_driver = {
+ .probe = intel_th_sth_probe,
+ .remove = intel_th_sth_remove,
+ .driver = {
+ .name = "sth",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_driver(intel_th_sth_driver,
+ intel_th_driver_register,
+ intel_th_driver_unregister);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel(R) Trace Hub Software Trace Hub driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@intel.com>");
diff --git a/drivers/hwtracing/intel_th/sth.h b/drivers/hwtracing/intel_th/sth.h
new file mode 100644
index 000000000000..f1390cd4f2ed
--- /dev/null
+++ b/drivers/hwtracing/intel_th/sth.h
@@ -0,0 +1,42 @@
+/*
+ * Intel(R) Trace Hub Software Trace Hub (STH) data structures
+ *
+ * Copyright (C) 2014-2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#ifndef __INTEL_TH_STH_H__
+#define __INTEL_TH_STH_H__
+
+enum {
+ REG_STH_STHCAP0 = 0x0000, /* capabilities pt1 */
+ REG_STH_STHCAP1 = 0x0004, /* capabilities pt2 */
+ REG_STH_TRIG = 0x0008, /* TRIG packet payload */
+ REG_STH_TRIG_TS = 0x000c, /* TRIG_TS packet payload */
+ REG_STH_XSYNC = 0x0010, /* XSYNC packet payload */
+ REG_STH_XSYNC_TS = 0x0014, /* XSYNC_TS packet payload */
+ REG_STH_GERR = 0x0018, /* GERR packet payload */
+};
+
+struct intel_th_channel {
+ u64 Dn;
+ u64 DnM;
+ u64 DnTS;
+ u64 DnMTS;
+ u64 USER;
+ u64 USER_TS;
+ u32 FLAG;
+ u32 FLAG_TS;
+ u32 MERR;
+ u32 __unused;
+} __packed;
+
+#endif /* __INTEL_TH_STH_H__ */
diff --git a/drivers/hwtracing/stm/Kconfig b/drivers/hwtracing/stm/Kconfig
new file mode 100644
index 000000000000..83e9f591a54b
--- /dev/null
+++ b/drivers/hwtracing/stm/Kconfig
@@ -0,0 +1,26 @@
+config STM
+ tristate "System Trace Module devices"
+ select CONFIGFS_FS
+ help
+ A System Trace Module (STM) is a device exporting data in System
+ Trace Protocol (STP) format as defined by MIPI STP standards.
+ Examples of such devices are Intel(R) Trace Hub and Coresight STM.
+
+ Say Y here to enable System Trace Module device support.
+
+config STM_DUMMY
+ tristate "Dummy STM driver"
+ help
+ This is a simple dummy device that pretends to be an stm device
+ and discards your data. Use for stm class testing.
+
+ If you don't know what this is, say N.
+
+config STM_SOURCE_CONSOLE
+ tristate "Kernel console over STM devices"
+ help
+ This is a kernel space trace source that sends kernel log
+ messages to trace hosts over STM devices.
+
+ If you want to send kernel console messages over STM devices,
+ say Y.
diff --git a/drivers/hwtracing/stm/Makefile b/drivers/hwtracing/stm/Makefile
new file mode 100644
index 000000000000..f9312c38dd7a
--- /dev/null
+++ b/drivers/hwtracing/stm/Makefile
@@ -0,0 +1,9 @@
+obj-$(CONFIG_STM) += stm_core.o
+
+stm_core-y := core.o policy.o
+
+obj-$(CONFIG_STM_DUMMY) += dummy_stm.o
+
+obj-$(CONFIG_STM_SOURCE_CONSOLE) += stm_console.o
+
+stm_console-y := console.o
diff --git a/drivers/hwtracing/stm/console.c b/drivers/hwtracing/stm/console.c
new file mode 100644
index 000000000000..c9d9a8d2ff52
--- /dev/null
+++ b/drivers/hwtracing/stm/console.c
@@ -0,0 +1,80 @@
+/*
+ * Simple kernel console driver for STM devices
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * STM console will send kernel messages over STM devices to a trace host.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/console.h>
+#include <linux/slab.h>
+#include <linux/stm.h>
+
+static int stm_console_link(struct stm_source_data *data);
+static void stm_console_unlink(struct stm_source_data *data);
+
+static struct stm_console {
+ struct stm_source_data data;
+ struct console console;
+} stm_console = {
+ .data = {
+ .name = "console",
+ .nr_chans = 1,
+ .link = stm_console_link,
+ .unlink = stm_console_unlink,
+ },
+};
+
+static void
+stm_console_write(struct console *con, const char *buf, unsigned len)
+{
+ struct stm_console *sc = container_of(con, struct stm_console, console);
+
+ stm_source_write(&sc->data, 0, buf, len);
+}
+
+static int stm_console_link(struct stm_source_data *data)
+{
+ struct stm_console *sc = container_of(data, struct stm_console, data);
+
+ strcpy(sc->console.name, "stm_console");
+ sc->console.write = stm_console_write;
+ sc->console.flags = CON_ENABLED | CON_PRINTBUFFER;
+ register_console(&sc->console);
+
+ return 0;
+}
+
+static void stm_console_unlink(struct stm_source_data *data)
+{
+ struct stm_console *sc = container_of(data, struct stm_console, data);
+
+ unregister_console(&sc->console);
+}
+
+static int stm_console_init(void)
+{
+ return stm_source_register_device(NULL, &stm_console.data);
+}
+
+static void stm_console_exit(void)
+{
+ stm_source_unregister_device(&stm_console.data);
+}
+
+module_init(stm_console_init);
+module_exit(stm_console_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("stm_console driver");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/stm/core.c b/drivers/hwtracing/stm/core.c
new file mode 100644
index 000000000000..b6445d9e5453
--- /dev/null
+++ b/drivers/hwtracing/stm/core.c
@@ -0,0 +1,1032 @@
+/*
+ * System Trace Module (STM) infrastructure
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * STM class implements generic infrastructure for System Trace Module devices
+ * as defined in MIPI STPv2 specification.
+ */
+
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/compat.h>
+#include <linux/kdev_t.h>
+#include <linux/srcu.h>
+#include <linux/slab.h>
+#include <linux/stm.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include "stm.h"
+
+#include <uapi/linux/stm.h>
+
+static unsigned int stm_core_up;
+
+/*
+ * The SRCU here makes sure that STM device doesn't disappear from under a
+ * stm_source_write() caller, which may want to have as little overhead as
+ * possible.
+ */
+static struct srcu_struct stm_source_srcu;
+
+static ssize_t masters_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct stm_device *stm = to_stm_device(dev);
+ int ret;
+
+ ret = sprintf(buf, "%u %u\n", stm->data->sw_start, stm->data->sw_end);
+
+ return ret;
+}
+
+static DEVICE_ATTR_RO(masters);
+
+static ssize_t channels_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct stm_device *stm = to_stm_device(dev);
+ int ret;
+
+ ret = sprintf(buf, "%u\n", stm->data->sw_nchannels);
+
+ return ret;
+}
+
+static DEVICE_ATTR_RO(channels);
+
+static struct attribute *stm_attrs[] = {
+ &dev_attr_masters.attr,
+ &dev_attr_channels.attr,
+ NULL,
+};
+
+ATTRIBUTE_GROUPS(stm);
+
+static struct class stm_class = {
+ .name = "stm",
+ .dev_groups = stm_groups,
+};
+
+static int stm_dev_match(struct device *dev, const void *data)
+{
+ const char *name = data;
+
+ return sysfs_streq(name, dev_name(dev));
+}
+
+/**
+ * stm_find_device() - find stm device by name
+ * @buf: character buffer containing the name
+ *
+ * This is called when either policy gets assigned to an stm device or an
+ * stm_source device gets linked to an stm device.
+ *
+ * This grabs device's reference (get_device()) and module reference, both
+ * of which the calling path needs to make sure to drop with stm_put_device().
+ *
+ * Return: stm device pointer or null if lookup failed.
+ */
+struct stm_device *stm_find_device(const char *buf)
+{
+ struct stm_device *stm;
+ struct device *dev;
+
+ if (!stm_core_up)
+ return NULL;
+
+ dev = class_find_device(&stm_class, NULL, buf, stm_dev_match);
+ if (!dev)
+ return NULL;
+
+ stm = to_stm_device(dev);
+ if (!try_module_get(stm->owner)) {
+ put_device(dev);
+ return NULL;
+ }
+
+ return stm;
+}
+
+/**
+ * stm_put_device() - drop references on the stm device
+ * @stm: stm device, previously acquired by stm_find_device()
+ *
+ * This drops the module reference and device reference taken by
+ * stm_find_device().
+ */
+void stm_put_device(struct stm_device *stm)
+{
+ module_put(stm->owner);
+ put_device(&stm->dev);
+}
+
+/*
+ * Internally we only care about software-writable masters here, that is the
+ * ones in the range [stm_data->sw_start..stm_data..sw_end], however we need
+ * original master numbers to be visible externally, since they are the ones
+ * that will appear in the STP stream. Thus, the internal bookkeeping uses
+ * $master - stm_data->sw_start to reference master descriptors and such.
+ */
+
+#define __stm_master(_s, _m) \
+ ((_s)->masters[(_m) - (_s)->data->sw_start])
+
+static inline struct stp_master *
+stm_master(struct stm_device *stm, unsigned int idx)
+{
+ if (idx < stm->data->sw_start || idx > stm->data->sw_end)
+ return NULL;
+
+ return __stm_master(stm, idx);
+}
+
+static int stp_master_alloc(struct stm_device *stm, unsigned int idx)
+{
+ struct stp_master *master;
+ size_t size;
+
+ size = ALIGN(stm->data->sw_nchannels, 8) / 8;
+ size += sizeof(struct stp_master);
+ master = kzalloc(size, GFP_ATOMIC);
+ if (!master)
+ return -ENOMEM;
+
+ master->nr_free = stm->data->sw_nchannels;
+ __stm_master(stm, idx) = master;
+
+ return 0;
+}
+
+static void stp_master_free(struct stm_device *stm, unsigned int idx)
+{
+ struct stp_master *master = stm_master(stm, idx);
+
+ if (!master)
+ return;
+
+ __stm_master(stm, idx) = NULL;
+ kfree(master);
+}
+
+static void stm_output_claim(struct stm_device *stm, struct stm_output *output)
+{
+ struct stp_master *master = stm_master(stm, output->master);
+
+ if (WARN_ON_ONCE(master->nr_free < output->nr_chans))
+ return;
+
+ bitmap_allocate_region(&master->chan_map[0], output->channel,
+ ilog2(output->nr_chans));
+
+ master->nr_free -= output->nr_chans;
+}
+
+static void
+stm_output_disclaim(struct stm_device *stm, struct stm_output *output)
+{
+ struct stp_master *master = stm_master(stm, output->master);
+
+ bitmap_release_region(&master->chan_map[0], output->channel,
+ ilog2(output->nr_chans));
+
+ output->nr_chans = 0;
+ master->nr_free += output->nr_chans;
+}
+
+/*
+ * This is like bitmap_find_free_region(), except it can ignore @start bits
+ * at the beginning.
+ */
+static int find_free_channels(unsigned long *bitmap, unsigned int start,
+ unsigned int end, unsigned int width)
+{
+ unsigned int pos;
+ int i;
+
+ for (pos = start; pos < end + 1; pos = ALIGN(pos, width)) {
+ pos = find_next_zero_bit(bitmap, end + 1, pos);
+ if (pos + width > end + 1)
+ break;
+
+ if (pos & (width - 1))
+ continue;
+
+ for (i = 1; i < width && !test_bit(pos + i, bitmap); i++)
+ ;
+ if (i == width)
+ return pos;
+ }
+
+ return -1;
+}
+
+static unsigned int
+stm_find_master_chan(struct stm_device *stm, unsigned int width,
+ unsigned int *mstart, unsigned int mend,
+ unsigned int *cstart, unsigned int cend)
+{
+ struct stp_master *master;
+ unsigned int midx;
+ int pos, err;
+
+ for (midx = *mstart; midx <= mend; midx++) {
+ if (!stm_master(stm, midx)) {
+ err = stp_master_alloc(stm, midx);
+ if (err)
+ return err;
+ }
+
+ master = stm_master(stm, midx);
+
+ if (!master->nr_free)
+ continue;
+
+ pos = find_free_channels(master->chan_map, *cstart, cend,
+ width);
+ if (pos < 0)
+ continue;
+
+ *mstart = midx;
+ *cstart = pos;
+ return 0;
+ }
+
+ return -ENOSPC;
+}
+
+static int stm_output_assign(struct stm_device *stm, unsigned int width,
+ struct stp_policy_node *policy_node,
+ struct stm_output *output)
+{
+ unsigned int midx, cidx, mend, cend;
+ int ret = -EINVAL;
+
+ if (width > stm->data->sw_nchannels)
+ return -EINVAL;
+
+ if (policy_node) {
+ stp_policy_node_get_ranges(policy_node,
+ &midx, &mend, &cidx, &cend);
+ } else {
+ midx = stm->data->sw_start;
+ cidx = 0;
+ mend = stm->data->sw_end;
+ cend = stm->data->sw_nchannels - 1;
+ }
+
+ spin_lock(&stm->mc_lock);
+ /* output is already assigned -- shouldn't happen */
+ if (WARN_ON_ONCE(output->nr_chans))
+ goto unlock;
+
+ ret = stm_find_master_chan(stm, width, &midx, mend, &cidx, cend);
+ if (ret)
+ goto unlock;
+
+ output->master = midx;
+ output->channel = cidx;
+ output->nr_chans = width;
+ stm_output_claim(stm, output);
+ dev_dbg(&stm->dev, "assigned %u:%u (+%u)\n", midx, cidx, width);
+
+ ret = 0;
+unlock:
+ spin_unlock(&stm->mc_lock);
+
+ return ret;
+}
+
+static void stm_output_free(struct stm_device *stm, struct stm_output *output)
+{
+ spin_lock(&stm->mc_lock);
+ if (output->nr_chans)
+ stm_output_disclaim(stm, output);
+ spin_unlock(&stm->mc_lock);
+}
+
+static int major_match(struct device *dev, const void *data)
+{
+ unsigned int major = *(unsigned int *)data;
+
+ return MAJOR(dev->devt) == major;
+}
+
+static int stm_char_open(struct inode *inode, struct file *file)
+{
+ struct stm_file *stmf;
+ struct device *dev;
+ unsigned int major = imajor(inode);
+ int err = -ENODEV;
+
+ dev = class_find_device(&stm_class, NULL, &major, major_match);
+ if (!dev)
+ return -ENODEV;
+
+ stmf = kzalloc(sizeof(*stmf), GFP_KERNEL);
+ if (!stmf)
+ return -ENOMEM;
+
+ stmf->stm = to_stm_device(dev);
+
+ if (!try_module_get(stmf->stm->owner))
+ goto err_free;
+
+ file->private_data = stmf;
+
+ return nonseekable_open(inode, file);
+
+err_free:
+ kfree(stmf);
+
+ return err;
+}
+
+static int stm_char_release(struct inode *inode, struct file *file)
+{
+ struct stm_file *stmf = file->private_data;
+
+ stm_output_free(stmf->stm, &stmf->output);
+ stm_put_device(stmf->stm);
+ kfree(stmf);
+
+ return 0;
+}
+
+static int stm_file_assign(struct stm_file *stmf, char *id, unsigned int width)
+{
+ struct stm_device *stm = stmf->stm;
+ int ret;
+
+ stmf->policy_node = stp_policy_node_lookup(stm, id);
+
+ ret = stm_output_assign(stm, width, stmf->policy_node, &stmf->output);
+
+ if (stmf->policy_node)
+ stp_policy_node_put(stmf->policy_node);
+
+ return ret;
+}
+
+static void stm_write(struct stm_data *data, unsigned int master,
+ unsigned int channel, const char *buf, size_t count)
+{
+ unsigned int flags = STP_PACKET_TIMESTAMPED;
+ const unsigned char *p = buf, nil = 0;
+ size_t pos;
+ ssize_t sz;
+
+ for (pos = 0, p = buf; count > pos; pos += sz, p += sz) {
+ sz = min_t(unsigned int, count - pos, 8);
+ sz = data->packet(data, master, channel, STP_PACKET_DATA, flags,
+ sz, p);
+ flags = 0;
+ }
+
+ data->packet(data, master, channel, STP_PACKET_FLAG, 0, 0, &nil);
+}
+
+static ssize_t stm_char_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct stm_file *stmf = file->private_data;
+ struct stm_device *stm = stmf->stm;
+ char *kbuf;
+ int err;
+
+ /*
+ * if no m/c have been assigned to this writer up to this
+ * point, use "default" policy entry
+ */
+ if (!stmf->output.nr_chans) {
+ err = stm_file_assign(stmf, "default", 1);
+ /*
+ * EBUSY means that somebody else just assigned this
+ * output, which is just fine for write()
+ */
+ if (err && err != -EBUSY)
+ return err;
+ }
+
+ kbuf = kmalloc(count + 1, GFP_KERNEL);
+ if (!kbuf)
+ return -ENOMEM;
+
+ err = copy_from_user(kbuf, buf, count);
+ if (err) {
+ kfree(kbuf);
+ return -EFAULT;
+ }
+
+ stm_write(stm->data, stmf->output.master, stmf->output.channel, kbuf,
+ count);
+
+ kfree(kbuf);
+
+ return count;
+}
+
+static int stm_char_mmap(struct file *file, struct vm_area_struct *vma)
+{
+ struct stm_file *stmf = file->private_data;
+ struct stm_device *stm = stmf->stm;
+ unsigned long size, phys;
+
+ if (!stm->data->mmio_addr)
+ return -EOPNOTSUPP;
+
+ if (vma->vm_pgoff)
+ return -EINVAL;
+
+ size = vma->vm_end - vma->vm_start;
+
+ if (stmf->output.nr_chans * stm->data->sw_mmiosz != size)
+ return -EINVAL;
+
+ phys = stm->data->mmio_addr(stm->data, stmf->output.master,
+ stmf->output.channel,
+ stmf->output.nr_chans);
+
+ if (!phys)
+ return -EINVAL;
+
+ vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+ vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
+ vm_iomap_memory(vma, phys, size);
+
+ return 0;
+}
+
+static int stm_char_policy_set_ioctl(struct stm_file *stmf, void __user *arg)
+{
+ struct stm_device *stm = stmf->stm;
+ struct stp_policy_id *id;
+ int ret = -EINVAL;
+ u32 size;
+
+ if (stmf->output.nr_chans)
+ return -EBUSY;
+
+ if (copy_from_user(&size, arg, sizeof(size)))
+ return -EFAULT;
+
+ if (size >= PATH_MAX + sizeof(*id))
+ return -EINVAL;
+
+ /*
+ * size + 1 to make sure the .id string at the bottom is terminated,
+ * which is also why memdup_user() is not useful here
+ */
+ id = kzalloc(size + 1, GFP_KERNEL);
+ if (!id)
+ return -ENOMEM;
+
+ if (copy_from_user(id, arg, size)) {
+ ret = -EFAULT;
+ goto err_free;
+ }
+
+ if (id->__reserved_0 || id->__reserved_1)
+ goto err_free;
+
+ if (id->width < 1 ||
+ id->width > PAGE_SIZE / stm->data->sw_mmiosz)
+ goto err_free;
+
+ ret = stm_file_assign(stmf, id->id, id->width);
+ if (ret)
+ goto err_free;
+
+ ret = 0;
+
+ if (stm->data->link)
+ ret = stm->data->link(stm->data, stmf->output.master,
+ stmf->output.channel);
+
+ if (ret) {
+ stm_output_free(stmf->stm, &stmf->output);
+ stm_put_device(stmf->stm);
+ }
+
+err_free:
+ kfree(id);
+
+ return ret;
+}
+
+static int stm_char_policy_get_ioctl(struct stm_file *stmf, void __user *arg)
+{
+ struct stp_policy_id id = {
+ .size = sizeof(id),
+ .master = stmf->output.master,
+ .channel = stmf->output.channel,
+ .width = stmf->output.nr_chans,
+ .__reserved_0 = 0,
+ .__reserved_1 = 0,
+ };
+
+ return copy_to_user(arg, &id, id.size) ? -EFAULT : 0;
+}
+
+static long
+stm_char_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ struct stm_file *stmf = file->private_data;
+ struct stm_data *stm_data = stmf->stm->data;
+ int err = -ENOTTY;
+ u64 options;
+
+ switch (cmd) {
+ case STP_POLICY_ID_SET:
+ err = stm_char_policy_set_ioctl(stmf, (void __user *)arg);
+ if (err)
+ return err;
+
+ return stm_char_policy_get_ioctl(stmf, (void __user *)arg);
+
+ case STP_POLICY_ID_GET:
+ return stm_char_policy_get_ioctl(stmf, (void __user *)arg);
+
+ case STP_SET_OPTIONS:
+ if (copy_from_user(&options, (u64 __user *)arg, sizeof(u64)))
+ return -EFAULT;
+
+ if (stm_data->set_options)
+ err = stm_data->set_options(stm_data,
+ stmf->output.master,
+ stmf->output.channel,
+ stmf->output.nr_chans,
+ options);
+
+ break;
+ default:
+ break;
+ }
+
+ return err;
+}
+
+#ifdef CONFIG_COMPAT
+static long
+stm_char_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+ return stm_char_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
+}
+#else
+#define stm_char_compat_ioctl NULL
+#endif
+
+static const struct file_operations stm_fops = {
+ .open = stm_char_open,
+ .release = stm_char_release,
+ .write = stm_char_write,
+ .mmap = stm_char_mmap,
+ .unlocked_ioctl = stm_char_ioctl,
+ .compat_ioctl = stm_char_compat_ioctl,
+ .llseek = no_llseek,
+};
+
+static void stm_device_release(struct device *dev)
+{
+ struct stm_device *stm = to_stm_device(dev);
+
+ kfree(stm);
+}
+
+int stm_register_device(struct device *parent, struct stm_data *stm_data,
+ struct module *owner)
+{
+ struct stm_device *stm;
+ unsigned int nmasters;
+ int err = -ENOMEM;
+
+ if (!stm_core_up)
+ return -EPROBE_DEFER;
+
+ if (!stm_data->packet || !stm_data->sw_nchannels)
+ return -EINVAL;
+
+ nmasters = stm_data->sw_end - stm_data->sw_start;
+ stm = kzalloc(sizeof(*stm) + nmasters * sizeof(void *), GFP_KERNEL);
+ if (!stm)
+ return -ENOMEM;
+
+ stm->major = register_chrdev(0, stm_data->name, &stm_fops);
+ if (stm->major < 0)
+ goto err_free;
+
+ device_initialize(&stm->dev);
+ stm->dev.devt = MKDEV(stm->major, 0);
+ stm->dev.class = &stm_class;
+ stm->dev.parent = parent;
+ stm->dev.release = stm_device_release;
+
+ err = kobject_set_name(&stm->dev.kobj, "%s", stm_data->name);
+ if (err)
+ goto err_device;
+
+ err = device_add(&stm->dev);
+ if (err)
+ goto err_device;
+
+ spin_lock_init(&stm->link_lock);
+ INIT_LIST_HEAD(&stm->link_list);
+
+ spin_lock_init(&stm->mc_lock);
+ mutex_init(&stm->policy_mutex);
+ stm->sw_nmasters = nmasters;
+ stm->owner = owner;
+ stm->data = stm_data;
+ stm_data->stm = stm;
+
+ return 0;
+
+err_device:
+ put_device(&stm->dev);
+err_free:
+ kfree(stm);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(stm_register_device);
+
+static void __stm_source_link_drop(struct stm_source_device *src,
+ struct stm_device *stm);
+
+void stm_unregister_device(struct stm_data *stm_data)
+{
+ struct stm_device *stm = stm_data->stm;
+ struct stm_source_device *src, *iter;
+ int i;
+
+ spin_lock(&stm->link_lock);
+ list_for_each_entry_safe(src, iter, &stm->link_list, link_entry) {
+ __stm_source_link_drop(src, stm);
+ }
+ spin_unlock(&stm->link_lock);
+
+ synchronize_srcu(&stm_source_srcu);
+
+ unregister_chrdev(stm->major, stm_data->name);
+
+ mutex_lock(&stm->policy_mutex);
+ if (stm->policy)
+ stp_policy_unbind(stm->policy);
+ mutex_unlock(&stm->policy_mutex);
+
+ for (i = 0; i < stm->sw_nmasters; i++)
+ stp_master_free(stm, i);
+
+ device_unregister(&stm->dev);
+ stm_data->stm = NULL;
+}
+EXPORT_SYMBOL_GPL(stm_unregister_device);
+
+/**
+ * stm_source_link_add() - connect an stm_source device to an stm device
+ * @src: stm_source device
+ * @stm: stm device
+ *
+ * This function establishes a link from stm_source to an stm device so that
+ * the former can send out trace data to the latter.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+static int stm_source_link_add(struct stm_source_device *src,
+ struct stm_device *stm)
+{
+ char *id;
+ int err;
+
+ spin_lock(&stm->link_lock);
+ spin_lock(&src->link_lock);
+
+ /* src->link is dereferenced under stm_source_srcu but not the list */
+ rcu_assign_pointer(src->link, stm);
+ list_add_tail(&src->link_entry, &stm->link_list);
+
+ spin_unlock(&src->link_lock);
+ spin_unlock(&stm->link_lock);
+
+ id = kstrdup(src->data->name, GFP_KERNEL);
+ if (id) {
+ src->policy_node =
+ stp_policy_node_lookup(stm, id);
+
+ kfree(id);
+ }
+
+ err = stm_output_assign(stm, src->data->nr_chans,
+ src->policy_node, &src->output);
+
+ if (src->policy_node)
+ stp_policy_node_put(src->policy_node);
+
+ if (err)
+ goto fail_detach;
+
+ /* this is to notify the STM device that a new link has been made */
+ if (stm->data->link)
+ err = stm->data->link(stm->data, src->output.master,
+ src->output.channel);
+
+ if (err)
+ goto fail_free_output;
+
+ /* this is to let the source carry out all necessary preparations */
+ if (src->data->link)
+ src->data->link(src->data);
+
+ return 0;
+
+fail_free_output:
+ stm_output_free(stm, &src->output);
+ stm_put_device(stm);
+
+fail_detach:
+ spin_lock(&stm->link_lock);
+ spin_lock(&src->link_lock);
+
+ rcu_assign_pointer(src->link, NULL);
+ list_del_init(&src->link_entry);
+
+ spin_unlock(&src->link_lock);
+ spin_unlock(&stm->link_lock);
+
+ return err;
+}
+
+/**
+ * __stm_source_link_drop() - detach stm_source from an stm device
+ * @src: stm_source device
+ * @stm: stm device
+ *
+ * If @stm is @src::link, disconnect them from one another and put the
+ * reference on the @stm device.
+ *
+ * Caller must hold stm::link_lock.
+ */
+static void __stm_source_link_drop(struct stm_source_device *src,
+ struct stm_device *stm)
+{
+ struct stm_device *link;
+
+ spin_lock(&src->link_lock);
+ link = srcu_dereference_check(src->link, &stm_source_srcu, 1);
+ if (WARN_ON_ONCE(link != stm)) {
+ spin_unlock(&src->link_lock);
+ return;
+ }
+
+ stm_output_free(link, &src->output);
+ /* caller must hold stm::link_lock */
+ list_del_init(&src->link_entry);
+ /* matches stm_find_device() from stm_source_link_store() */
+ stm_put_device(link);
+ rcu_assign_pointer(src->link, NULL);
+
+ spin_unlock(&src->link_lock);
+}
+
+/**
+ * stm_source_link_drop() - detach stm_source from its stm device
+ * @src: stm_source device
+ *
+ * Unlinking means disconnecting from source's STM device; after this
+ * writes will be unsuccessful until it is linked to a new STM device.
+ *
+ * This will happen on "stm_source_link" sysfs attribute write to undo
+ * the existing link (if any), or on linked STM device's de-registration.
+ */
+static void stm_source_link_drop(struct stm_source_device *src)
+{
+ struct stm_device *stm;
+ int idx;
+
+ idx = srcu_read_lock(&stm_source_srcu);
+ stm = srcu_dereference(src->link, &stm_source_srcu);
+
+ if (stm) {
+ if (src->data->unlink)
+ src->data->unlink(src->data);
+
+ spin_lock(&stm->link_lock);
+ __stm_source_link_drop(src, stm);
+ spin_unlock(&stm->link_lock);
+ }
+
+ srcu_read_unlock(&stm_source_srcu, idx);
+}
+
+static ssize_t stm_source_link_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct stm_source_device *src = to_stm_source_device(dev);
+ struct stm_device *stm;
+ int idx, ret;
+
+ idx = srcu_read_lock(&stm_source_srcu);
+ stm = srcu_dereference(src->link, &stm_source_srcu);
+ ret = sprintf(buf, "%s\n",
+ stm ? dev_name(&stm->dev) : "<none>");
+ srcu_read_unlock(&stm_source_srcu, idx);
+
+ return ret;
+}
+
+static ssize_t stm_source_link_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct stm_source_device *src = to_stm_source_device(dev);
+ struct stm_device *link;
+ int err;
+
+ stm_source_link_drop(src);
+
+ link = stm_find_device(buf);
+ if (!link)
+ return -EINVAL;
+
+ err = stm_source_link_add(src, link);
+ if (err)
+ stm_put_device(link);
+
+ return err ? : count;
+}
+
+static DEVICE_ATTR_RW(stm_source_link);
+
+static struct attribute *stm_source_attrs[] = {
+ &dev_attr_stm_source_link.attr,
+ NULL,
+};
+
+ATTRIBUTE_GROUPS(stm_source);
+
+static struct class stm_source_class = {
+ .name = "stm_source",
+ .dev_groups = stm_source_groups,
+};
+
+static void stm_source_device_release(struct device *dev)
+{
+ struct stm_source_device *src = to_stm_source_device(dev);
+
+ kfree(src);
+}
+
+/**
+ * stm_source_register_device() - register an stm_source device
+ * @parent: parent device
+ * @data: device description structure
+ *
+ * This will create a device of stm_source class that can write
+ * data to an stm device once linked.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+int stm_source_register_device(struct device *parent,
+ struct stm_source_data *data)
+{
+ struct stm_source_device *src;
+ int err;
+
+ if (!stm_core_up)
+ return -EPROBE_DEFER;
+
+ src = kzalloc(sizeof(*src), GFP_KERNEL);
+ if (!src)
+ return -ENOMEM;
+
+ device_initialize(&src->dev);
+ src->dev.class = &stm_source_class;
+ src->dev.parent = parent;
+ src->dev.release = stm_source_device_release;
+
+ err = kobject_set_name(&src->dev.kobj, "%s", data->name);
+ if (err)
+ goto err;
+
+ err = device_add(&src->dev);
+ if (err)
+ goto err;
+
+ spin_lock_init(&src->link_lock);
+ INIT_LIST_HEAD(&src->link_entry);
+ src->data = data;
+ data->src = src;
+
+ return 0;
+
+err:
+ put_device(&src->dev);
+ kfree(src);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(stm_source_register_device);
+
+/**
+ * stm_source_unregister_device() - unregister an stm_source device
+ * @data: device description that was used to register the device
+ *
+ * This will remove a previously created stm_source device from the system.
+ */
+void stm_source_unregister_device(struct stm_source_data *data)
+{
+ struct stm_source_device *src = data->src;
+
+ stm_source_link_drop(src);
+
+ device_destroy(&stm_source_class, src->dev.devt);
+}
+EXPORT_SYMBOL_GPL(stm_source_unregister_device);
+
+int stm_source_write(struct stm_source_data *data, unsigned int chan,
+ const char *buf, size_t count)
+{
+ struct stm_source_device *src = data->src;
+ struct stm_device *stm;
+ int idx;
+
+ if (!src->output.nr_chans)
+ return -ENODEV;
+
+ if (chan >= src->output.nr_chans)
+ return -EINVAL;
+
+ idx = srcu_read_lock(&stm_source_srcu);
+
+ stm = srcu_dereference(src->link, &stm_source_srcu);
+ if (stm)
+ stm_write(stm->data, src->output.master,
+ src->output.channel + chan,
+ buf, count);
+ else
+ count = -ENODEV;
+
+ srcu_read_unlock(&stm_source_srcu, idx);
+
+ return count;
+}
+EXPORT_SYMBOL_GPL(stm_source_write);
+
+static int __init stm_core_init(void)
+{
+ int err;
+
+ err = class_register(&stm_class);
+ if (err)
+ return err;
+
+ err = class_register(&stm_source_class);
+ if (err)
+ goto err_stm;
+
+ err = stp_configfs_init();
+ if (err)
+ goto err_src;
+
+ init_srcu_struct(&stm_source_srcu);
+
+ stm_core_up++;
+
+ return 0;
+
+err_src:
+ class_unregister(&stm_source_class);
+err_stm:
+ class_unregister(&stm_class);
+
+ return err;
+}
+
+module_init(stm_core_init);
+
+static void __exit stm_core_exit(void)
+{
+ cleanup_srcu_struct(&stm_source_srcu);
+ class_unregister(&stm_source_class);
+ class_unregister(&stm_class);
+ stp_configfs_exit();
+}
+
+module_exit(stm_core_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("System Trace Module device class");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/stm/dummy_stm.c b/drivers/hwtracing/stm/dummy_stm.c
new file mode 100644
index 000000000000..3709bef0b21f
--- /dev/null
+++ b/drivers/hwtracing/stm/dummy_stm.c
@@ -0,0 +1,66 @@
+/*
+ * A dummy STM device for stm/stm_source class testing.
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * STM class implements generic infrastructure for System Trace Module devices
+ * as defined in MIPI STPv2 specification.
+ */
+
+#undef DEBUG
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/stm.h>
+
+static ssize_t
+dummy_stm_packet(struct stm_data *stm_data, unsigned int master,
+ unsigned int channel, unsigned int packet, unsigned int flags,
+ unsigned int size, const unsigned char *payload)
+{
+#ifdef DEBUG
+ u64 pl = 0;
+
+ if (payload)
+ pl = *(u64 *)payload;
+
+ if (size < 8)
+ pl &= (1ull << (size * 8)) - 1;
+ trace_printk("[%u:%u] [pkt: %x/%x] (%llx)\n", master, channel,
+ packet, size, pl);
+#endif
+ return size;
+}
+
+static struct stm_data dummy_stm = {
+ .name = "dummy_stm",
+ .sw_start = 0x0000,
+ .sw_end = 0xffff,
+ .sw_nchannels = 0xffff,
+ .packet = dummy_stm_packet,
+};
+
+static int dummy_stm_init(void)
+{
+ return stm_register_device(NULL, &dummy_stm, THIS_MODULE);
+}
+
+static void dummy_stm_exit(void)
+{
+ stm_unregister_device(&dummy_stm);
+}
+
+module_init(dummy_stm_init);
+module_exit(dummy_stm_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("dummy_stm device");
+MODULE_AUTHOR("Alexander Shishkin <alexander.shishkin@linux.intel.com>");
diff --git a/drivers/hwtracing/stm/policy.c b/drivers/hwtracing/stm/policy.c
new file mode 100644
index 000000000000..6498a9dbb7bd
--- /dev/null
+++ b/drivers/hwtracing/stm/policy.c
@@ -0,0 +1,529 @@
+/*
+ * System Trace Module (STM) master/channel allocation policy management
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * A master/channel allocation policy allows mapping string identifiers to
+ * master and channel ranges, where allocation can be done.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/configfs.h>
+#include <linux/slab.h>
+#include <linux/stm.h>
+#include "stm.h"
+
+/*
+ * STP Master/Channel allocation policy configfs layout.
+ */
+
+struct stp_policy {
+ struct config_group group;
+ struct stm_device *stm;
+};
+
+struct stp_policy_node {
+ struct config_group group;
+ struct stp_policy *policy;
+ unsigned int first_master;
+ unsigned int last_master;
+ unsigned int first_channel;
+ unsigned int last_channel;
+};
+
+static struct configfs_subsystem stp_policy_subsys;
+
+void stp_policy_node_get_ranges(struct stp_policy_node *policy_node,
+ unsigned int *mstart, unsigned int *mend,
+ unsigned int *cstart, unsigned int *cend)
+{
+ *mstart = policy_node->first_master;
+ *mend = policy_node->last_master;
+ *cstart = policy_node->first_channel;
+ *cend = policy_node->last_channel;
+}
+
+static inline char *stp_policy_node_name(struct stp_policy_node *policy_node)
+{
+ return policy_node->group.cg_item.ci_name ? : "<none>";
+}
+
+static inline struct stp_policy *to_stp_policy(struct config_item *item)
+{
+ return item ?
+ container_of(to_config_group(item), struct stp_policy, group) :
+ NULL;
+}
+
+static inline struct stp_policy_node *
+to_stp_policy_node(struct config_item *item)
+{
+ return item ?
+ container_of(to_config_group(item), struct stp_policy_node,
+ group) :
+ NULL;
+}
+
+static ssize_t stp_policy_node_masters_show(struct stp_policy_node *policy_node,
+ char *page)
+{
+ ssize_t count;
+
+ count = sprintf(page, "%u %u\n", policy_node->first_master,
+ policy_node->last_master);
+
+ return count;
+}
+
+static ssize_t
+stp_policy_node_masters_store(struct stp_policy_node *policy_node,
+ const char *page, size_t count)
+{
+ unsigned int first, last;
+ struct stm_device *stm;
+ char *p = (char *)page;
+ ssize_t ret = -ENODEV;
+
+ if (sscanf(p, "%u %u", &first, &last) != 2)
+ return -EINVAL;
+
+ mutex_lock(&stp_policy_subsys.su_mutex);
+ stm = policy_node->policy->stm;
+ if (!stm)
+ goto unlock;
+
+ /* must be within [sw_start..sw_end], which is an inclusive range */
+ if (first > INT_MAX || last > INT_MAX || first > last ||
+ first < stm->data->sw_start ||
+ last > stm->data->sw_end) {
+ ret = -ERANGE;
+ goto unlock;
+ }
+
+ ret = count;
+ policy_node->first_master = first;
+ policy_node->last_master = last;
+
+unlock:
+ mutex_unlock(&stp_policy_subsys.su_mutex);
+
+ return ret;
+}
+
+static ssize_t
+stp_policy_node_channels_show(struct stp_policy_node *policy_node, char *page)
+{
+ ssize_t count;
+
+ count = sprintf(page, "%u %u\n", policy_node->first_channel,
+ policy_node->last_channel);
+
+ return count;
+}
+
+static ssize_t
+stp_policy_node_channels_store(struct stp_policy_node *policy_node,
+ const char *page, size_t count)
+{
+ unsigned int first, last;
+ struct stm_device *stm;
+ char *p = (char *)page;
+ ssize_t ret = -ENODEV;
+
+ if (sscanf(p, "%u %u", &first, &last) != 2)
+ return -EINVAL;
+
+ mutex_lock(&stp_policy_subsys.su_mutex);
+ stm = policy_node->policy->stm;
+ if (!stm)
+ goto unlock;
+
+ if (first > INT_MAX || last > INT_MAX || first > last ||
+ last >= stm->data->sw_nchannels) {
+ ret = -ERANGE;
+ goto unlock;
+ }
+
+ ret = count;
+ policy_node->first_channel = first;
+ policy_node->last_channel = last;
+
+unlock:
+ mutex_unlock(&stp_policy_subsys.su_mutex);
+
+ return ret;
+}
+
+static void stp_policy_node_release(struct config_item *item)
+{
+ kfree(to_stp_policy_node(item));
+}
+
+struct stp_policy_node_attribute {
+ struct configfs_attribute attr;
+ ssize_t (*show)(struct stp_policy_node *, char *);
+ ssize_t (*store)(struct stp_policy_node *, const char *, size_t);
+};
+
+static ssize_t stp_policy_node_attr_show(struct config_item *item,
+ struct configfs_attribute *attr,
+ char *page)
+{
+ struct stp_policy_node *policy_node = to_stp_policy_node(item);
+ struct stp_policy_node_attribute *pn_attr =
+ container_of(attr, struct stp_policy_node_attribute, attr);
+ ssize_t count = 0;
+
+ if (pn_attr->show)
+ count = pn_attr->show(policy_node, page);
+
+ return count;
+}
+
+static ssize_t stp_policy_node_attr_store(struct config_item *item,
+ struct configfs_attribute *attr,
+ const char *page, size_t len)
+{
+ struct stp_policy_node *policy_node = to_stp_policy_node(item);
+ struct stp_policy_node_attribute *pn_attr =
+ container_of(attr, struct stp_policy_node_attribute, attr);
+ ssize_t count = -EINVAL;
+
+ if (pn_attr->store)
+ count = pn_attr->store(policy_node, page, len);
+
+ return count;
+}
+
+static struct configfs_item_operations stp_policy_node_item_ops = {
+ .release = stp_policy_node_release,
+ .show_attribute = stp_policy_node_attr_show,
+ .store_attribute = stp_policy_node_attr_store,
+};
+
+static struct stp_policy_node_attribute stp_policy_node_attr_range = {
+ .attr = {
+ .ca_owner = THIS_MODULE,
+ .ca_name = "masters",
+ .ca_mode = S_IRUGO | S_IWUSR,
+ },
+ .show = stp_policy_node_masters_show,
+ .store = stp_policy_node_masters_store,
+};
+
+static struct stp_policy_node_attribute stp_policy_node_attr_channels = {
+ .attr = {
+ .ca_owner = THIS_MODULE,
+ .ca_name = "channels",
+ .ca_mode = S_IRUGO | S_IWUSR,
+ },
+ .show = stp_policy_node_channels_show,
+ .store = stp_policy_node_channels_store,
+};
+
+static struct configfs_attribute *stp_policy_node_attrs[] = {
+ &stp_policy_node_attr_range.attr,
+ &stp_policy_node_attr_channels.attr,
+ NULL,
+};
+
+static struct config_item_type stp_policy_type;
+static struct config_item_type stp_policy_node_type;
+
+static struct config_group *
+stp_policy_node_make(struct config_group *group, const char *name)
+{
+ struct stp_policy_node *policy_node, *parent_node;
+ struct stp_policy *policy;
+
+ if (group->cg_item.ci_type == &stp_policy_type) {
+ policy = container_of(group, struct stp_policy, group);
+ } else {
+ parent_node = container_of(group, struct stp_policy_node,
+ group);
+ policy = parent_node->policy;
+ }
+
+ if (!policy->stm)
+ return ERR_PTR(-ENODEV);
+
+ policy_node = kzalloc(sizeof(struct stp_policy_node), GFP_KERNEL);
+ if (!policy_node)
+ return ERR_PTR(-ENOMEM);
+
+ config_group_init_type_name(&policy_node->group, name,
+ &stp_policy_node_type);
+
+ policy_node->policy = policy;
+
+ /* default values for the attributes */
+ policy_node->first_master = policy->stm->data->sw_start;
+ policy_node->last_master = policy->stm->data->sw_end;
+ policy_node->first_channel = 0;
+ policy_node->last_channel = policy->stm->data->sw_nchannels - 1;
+
+ return &policy_node->group;
+}
+
+static void
+stp_policy_node_drop(struct config_group *group, struct config_item *item)
+{
+ config_item_put(item);
+}
+
+static struct configfs_group_operations stp_policy_node_group_ops = {
+ .make_group = stp_policy_node_make,
+ .drop_item = stp_policy_node_drop,
+};
+
+static struct config_item_type stp_policy_node_type = {
+ .ct_item_ops = &stp_policy_node_item_ops,
+ .ct_group_ops = &stp_policy_node_group_ops,
+ .ct_attrs = stp_policy_node_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+/*
+ * Root group: policies.
+ */
+static struct configfs_attribute stp_policy_attr_device = {
+ .ca_owner = THIS_MODULE,
+ .ca_name = "device",
+ .ca_mode = S_IRUGO,
+};
+
+static struct configfs_attribute *stp_policy_attrs[] = {
+ &stp_policy_attr_device,
+ NULL,
+};
+
+static ssize_t stp_policy_attr_show(struct config_item *item,
+ struct configfs_attribute *attr,
+ char *page)
+{
+ struct stp_policy *policy = to_stp_policy(item);
+ ssize_t count;
+
+ count = sprintf(page, "%s\n",
+ (policy && policy->stm) ?
+ policy->stm->data->name :
+ "<none>");
+
+ return count;
+}
+
+void stp_policy_unbind(struct stp_policy *policy)
+{
+ struct stm_device *stm = policy->stm;
+
+ if (WARN_ON_ONCE(!policy->stm))
+ return;
+
+ mutex_lock(&stm->policy_mutex);
+ stm->policy = NULL;
+ mutex_unlock(&stm->policy_mutex);
+
+ policy->stm = NULL;
+
+ stm_put_device(stm);
+}
+
+static void stp_policy_release(struct config_item *item)
+{
+ struct stp_policy *policy = to_stp_policy(item);
+
+ stp_policy_unbind(policy);
+ kfree(policy);
+}
+
+static struct configfs_item_operations stp_policy_item_ops = {
+ .release = stp_policy_release,
+ .show_attribute = stp_policy_attr_show,
+};
+
+static struct configfs_group_operations stp_policy_group_ops = {
+ .make_group = stp_policy_node_make,
+};
+
+static struct config_item_type stp_policy_type = {
+ .ct_item_ops = &stp_policy_item_ops,
+ .ct_group_ops = &stp_policy_group_ops,
+ .ct_attrs = stp_policy_attrs,
+ .ct_owner = THIS_MODULE,
+};
+
+static struct config_group *
+stp_policies_make(struct config_group *group, const char *name)
+{
+ struct config_group *ret;
+ struct stm_device *stm;
+ char *devname, *p;
+
+ devname = kasprintf(GFP_KERNEL, "%s", name);
+ if (!devname)
+ return ERR_PTR(-ENOMEM);
+
+ /*
+ * node must look like <device_name>.<policy_name>, where
+ * <device_name> is the name of an existing stm device and
+ * <policy_name> is an arbitrary string
+ */
+ p = strchr(devname, '.');
+ if (!p) {
+ kfree(devname);
+ return ERR_PTR(-EINVAL);
+ }
+
+ *p++ = '\0';
+
+ stm = stm_find_device(devname);
+ kfree(devname);
+
+ if (!stm)
+ return ERR_PTR(-ENODEV);
+
+ mutex_lock(&stm->policy_mutex);
+ if (stm->policy) {
+ ret = ERR_PTR(-EBUSY);
+ goto unlock_policy;
+ }
+
+ stm->policy = kzalloc(sizeof(*stm->policy), GFP_KERNEL);
+ if (!stm->policy) {
+ ret = ERR_PTR(-ENOMEM);
+ goto unlock_policy;
+ }
+
+ config_group_init_type_name(&stm->policy->group, name,
+ &stp_policy_type);
+ stm->policy->stm = stm;
+
+ ret = &stm->policy->group;
+
+unlock_policy:
+ mutex_unlock(&stm->policy_mutex);
+
+ if (IS_ERR(ret))
+ stm_put_device(stm);
+
+ return ret;
+}
+
+static struct configfs_group_operations stp_policies_group_ops = {
+ .make_group = stp_policies_make,
+};
+
+static struct config_item_type stp_policies_type = {
+ .ct_group_ops = &stp_policies_group_ops,
+ .ct_owner = THIS_MODULE,
+};
+
+static struct configfs_subsystem stp_policy_subsys = {
+ .su_group = {
+ .cg_item = {
+ .ci_namebuf = "stp-policy",
+ .ci_type = &stp_policies_type,
+ },
+ },
+};
+
+/*
+ * Lock the policy mutex from the outside
+ */
+static struct stp_policy_node *
+__stp_policy_node_lookup(struct stp_policy *policy, char *s)
+{
+ struct stp_policy_node *policy_node, *ret;
+ struct list_head *head = &policy->group.cg_children;
+ struct config_item *item;
+ char *start, *end = s;
+
+ if (list_empty(head))
+ return NULL;
+
+ /* return the first entry if everything else fails */
+ item = list_entry(head->next, struct config_item, ci_entry);
+ ret = to_stp_policy_node(item);
+
+next:
+ for (;;) {
+ start = strsep(&end, "/");
+ if (!start)
+ break;
+
+ if (!*start)
+ continue;
+
+ list_for_each_entry(item, head, ci_entry) {
+ policy_node = to_stp_policy_node(item);
+
+ if (!strcmp(start,
+ policy_node->group.cg_item.ci_name)) {
+ ret = policy_node;
+
+ if (!end)
+ goto out;
+
+ head = &policy_node->group.cg_children;
+ goto next;
+ }
+ }
+ break;
+ }
+
+out:
+ return ret;
+}
+
+
+struct stp_policy_node *
+stp_policy_node_lookup(struct stm_device *stm, char *s)
+{
+ struct stp_policy_node *policy_node = NULL;
+
+ mutex_lock(&stp_policy_subsys.su_mutex);
+
+ mutex_lock(&stm->policy_mutex);
+ if (stm->policy)
+ policy_node = __stp_policy_node_lookup(stm->policy, s);
+ mutex_unlock(&stm->policy_mutex);
+
+ if (policy_node)
+ config_item_get(&policy_node->group.cg_item);
+ mutex_unlock(&stp_policy_subsys.su_mutex);
+
+ return policy_node;
+}
+
+void stp_policy_node_put(struct stp_policy_node *policy_node)
+{
+ config_item_put(&policy_node->group.cg_item);
+}
+
+int __init stp_configfs_init(void)
+{
+ int err;
+
+ config_group_init(&stp_policy_subsys.su_group);
+ mutex_init(&stp_policy_subsys.su_mutex);
+ err = configfs_register_subsystem(&stp_policy_subsys);
+
+ return err;
+}
+
+void __exit stp_configfs_exit(void)
+{
+ configfs_unregister_subsystem(&stp_policy_subsys);
+}
diff --git a/drivers/hwtracing/stm/stm.h b/drivers/hwtracing/stm/stm.h
new file mode 100644
index 000000000000..95ece0292c99
--- /dev/null
+++ b/drivers/hwtracing/stm/stm.h
@@ -0,0 +1,87 @@
+/*
+ * System Trace Module (STM) infrastructure
+ * Copyright (c) 2014, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * STM class implements generic infrastructure for System Trace Module devices
+ * as defined in MIPI STPv2 specification.
+ */
+
+#ifndef _STM_STM_H_
+#define _STM_STM_H_
+
+struct stp_policy;
+struct stp_policy_node;
+
+struct stp_policy_node *
+stp_policy_node_lookup(struct stm_device *stm, char *s);
+void stp_policy_node_put(struct stp_policy_node *policy_node);
+void stp_policy_unbind(struct stp_policy *policy);
+
+void stp_policy_node_get_ranges(struct stp_policy_node *policy_node,
+ unsigned int *mstart, unsigned int *mend,
+ unsigned int *cstart, unsigned int *cend);
+int stp_configfs_init(void);
+void stp_configfs_exit(void);
+
+struct stp_master {
+ unsigned int nr_free;
+ unsigned long chan_map[0];
+};
+
+struct stm_device {
+ struct device dev;
+ struct module *owner;
+ struct stp_policy *policy;
+ struct mutex policy_mutex;
+ int major;
+ unsigned int sw_nmasters;
+ struct stm_data *data;
+ spinlock_t link_lock;
+ struct list_head link_list;
+ /* master allocation */
+ spinlock_t mc_lock;
+ struct stp_master *masters[0];
+};
+
+#define to_stm_device(_d) \
+ container_of((_d), struct stm_device, dev)
+
+struct stm_output {
+ unsigned int master;
+ unsigned int channel;
+ unsigned int nr_chans;
+};
+
+struct stm_file {
+ struct stm_device *stm;
+ struct stp_policy_node *policy_node;
+ struct stm_output output;
+};
+
+struct stm_device *stm_find_device(const char *name);
+void stm_put_device(struct stm_device *stm);
+
+struct stm_source_device {
+ struct device dev;
+ struct stm_source_data *data;
+ spinlock_t link_lock;
+ struct stm_device __rcu *link;
+ struct list_head link_entry;
+ /* one output per stm_source device */
+ struct stp_policy_node *policy_node;
+ struct stm_output output;
+};
+
+#define to_stm_source_device(_d) \
+ container_of((_d), struct stm_source_device, dev)
+
+#endif /* _STM_STM_H_ */