diff options
author | Alexander Shishkin <alexander.shishkin@linux.intel.com> | 2015-09-22 15:47:19 +0300 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-10-04 20:28:58 +0100 |
commit | 14cdbf041788f150ec3b323583b80bfd5775f73e (patch) | |
tree | 1e0236ddb73b20cfd4ffa047a37dafb4bd470aa9 | |
parent | ba82664c134ef7ab97808f09a3c5e894b0a4900d (diff) | |
download | linux-14cdbf041788f150ec3b323583b80bfd5775f73e.tar.bz2 |
intel_th: Add PTI output driver
Parallel Trace Interface (PTI) unit is a trace output device that sends
data over a PTI port.
The driver provides interfaces to configure bus width, bus clock divider
and mode. Tracing is enabled via output device's "active" attribute.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | Documentation/ABI/testing/sysfs-bus-intel_th-devices-pti | 24 | ||||
-rw-r--r-- | drivers/hwtracing/intel_th/Kconfig | 9 | ||||
-rw-r--r-- | drivers/hwtracing/intel_th/Makefile | 3 | ||||
-rw-r--r-- | drivers/hwtracing/intel_th/pti.c | 252 | ||||
-rw-r--r-- | drivers/hwtracing/intel_th/pti.h | 29 |
5 files changed, 317 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-bus-intel_th-devices-pti b/Documentation/ABI/testing/sysfs-bus-intel_th-devices-pti new file mode 100644 index 000000000000..df0b24fd0218 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-intel_th-devices-pti @@ -0,0 +1,24 @@ +What: /sys/bus/intel_th/devices/<intel_th_id>-pti/mode +Date: June 2015 +KernelVersion: 4.3 +Contact: Alexander Shishkin <alexander.shishkin@linux.intel.com> +Description: (RW) Configure PTI output width. Currently supported values + are 4, 8, 12, 16. + +What: /sys/bus/intel_th/devices/<intel_th_id>-pti/freerunning_clock +Date: June 2015 +KernelVersion: 4.3 +Contact: Alexander Shishkin <alexander.shishkin@linux.intel.com> +Description: (RW) 0: PTI trace clock acts as a strobe which only toggles + when there is trace data to send. 1: PTI trace clock is a + free-running clock. + +What: /sys/bus/intel_th/devices/<intel_th_id>-pti/clock_divider +Date: June 2015 +KernelVersion: 4.3 +Contact: Alexander Shishkin <alexander.shishkin@linux.intel.com> +Description: (RW) Configure PTI port clock divider: + - 0: Intel TH clock rate, + - 1: 1/2 Intel TH clock rate, + - 2: 1/4 Intel TH clock rate, + - 3: 1/8 Intel TH clock rate. diff --git a/drivers/hwtracing/intel_th/Kconfig b/drivers/hwtracing/intel_th/Kconfig index d9a1217e27bf..b7a9073d968b 100644 --- a/drivers/hwtracing/intel_th/Kconfig +++ b/drivers/hwtracing/intel_th/Kconfig @@ -54,6 +54,15 @@ config INTEL_TH_MSU 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 diff --git a/drivers/hwtracing/intel_th/Makefile b/drivers/hwtracing/intel_th/Makefile index 4636757df2a1..81d42fe918f7 100644 --- a/drivers/hwtracing/intel_th/Makefile +++ b/drivers/hwtracing/intel_th/Makefile @@ -13,3 +13,6 @@ 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/pti.c b/drivers/hwtracing/intel_th/pti.c new file mode 100644 index 000000000000..1e3bbc89825c --- /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 (IS_ERR(base)) + return PTR_ERR(base); + + 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__ */ |