7 files changed, 786 insertions, 0 deletions

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index 6ff30e25af55..45d3822c8c8c 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -110,4 +110,16 @@ config CORESIGHT_CPU_DEBUG
 	  properly, please refer Documentation/trace/coresight-cpu-debug.rst
 	  for detailed description and the example for usage.
 
+config CORESIGHT_CTI
+	bool "CoreSight Cross Trigger Interface (CTI) driver"
+	depends on ARM || ARM64
+	help
+	  This driver provides support for CoreSight CTI and CTM components.
+	  These provide hardware triggering events between CoreSight trace
+	  source and sink components. These can be used to halt trace or
+	  inject events into the trace stream. CTI also provides a software
+	  control to trigger the same halt events. This can provide fast trace
+	  halt compared to disabling sources and sinks normally in driver
+	  software.
+
 endif
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 3c0ac421e211..0e3e72f0f510 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -17,3 +17,6 @@ obj-$(CONFIG_CORESIGHT_SOURCE_ETM4X) += coresight-etm4x.o \
 obj-$(CONFIG_CORESIGHT_STM) += coresight-stm.o
 obj-$(CONFIG_CORESIGHT_CPU_DEBUG) += coresight-cpu-debug.o
 obj-$(CONFIG_CORESIGHT_CATU) += coresight-catu.o
+obj-$(CONFIG_CORESIGHT_CTI) += coresight-cti.o \
+				coresight-cti-platform.o \
+				coresight-cti-sysfs.o
diff --git a/drivers/hwtracing/coresight/coresight-cti-platform.c b/drivers/hwtracing/coresight/coresight-cti-platform.c
new file mode 100644
index 000000000000..665be86c585d
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-cti-platform.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019, The Linaro Limited. All rights reserved.
+ */
+
+#include <linux/of.h>
+
+#include "coresight-cti.h"
+
+/* get the hardware configuration & connection data. */
+int cti_plat_get_hw_data(struct device *dev,
+			 struct cti_drvdata *drvdata)
+{
+	int rc = 0;
+	struct cti_device *cti_dev = &drvdata->ctidev;
+
+	/* if no connections, just add a single default based on max IN-OUT */
+	if (cti_dev->nr_trig_con == 0)
+		rc = cti_add_default_connection(dev, drvdata);
+	return rc;
+}
+
+struct coresight_platform_data *
+coresight_cti_get_platform_data(struct device *dev)
+{
+	int ret = -ENOENT;
+	struct coresight_platform_data *pdata = NULL;
+	struct fwnode_handle *fwnode = dev_fwnode(dev);
+	struct cti_drvdata *drvdata = dev_get_drvdata(dev);
+
+	if (IS_ERR_OR_NULL(fwnode))
+		goto error;
+
+	/*
+	 * Alloc platform data but leave it zero init. CTI does not use the
+	 * same connection infrastructuree as trace path components but an
+	 * empty struct enables us to use the standard coresight component
+	 * registration code.
+	 */
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	/* get some CTI specifics */
+	ret = cti_plat_get_hw_data(dev, drvdata);
+
+	if (!ret)
+		return pdata;
+error:
+	return ERR_PTR(ret);
+}
diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
new file mode 100644
index 000000000000..6d2790568071
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
@@ -0,0 +1,83 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2019 Linaro Limited, All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#include <linux/coresight.h>
+
+#include "coresight-cti.h"
+
+/* basic attributes */
+static ssize_t enable_show(struct device *dev,
+			   struct device_attribute *attr,
+			   char *buf)
+{
+	int enable_req;
+	bool enabled, powered;
+	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	enable_req = atomic_read(&drvdata->config.enable_req_count);
+	spin_lock(&drvdata->spinlock);
+	powered = drvdata->config.hw_powered;
+	enabled = drvdata->config.hw_enabled;
+	spin_unlock(&drvdata->spinlock);
+
+	if (powered)
+		return sprintf(buf, "%d\n", enabled);
+	else
+		return sprintf(buf, "%d\n", !!enable_req);
+}
+
+static ssize_t enable_store(struct device *dev,
+			    struct device_attribute *attr,
+			    const char *buf, size_t size)
+{
+	int ret = 0;
+	unsigned long val;
+	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	if (val)
+		ret = cti_enable(drvdata->csdev);
+	else
+		ret = cti_disable(drvdata->csdev);
+	if (ret)
+		return ret;
+	return size;
+}
+static DEVICE_ATTR_RW(enable);
+
+static ssize_t powered_show(struct device *dev,
+			    struct device_attribute *attr,
+			    char *buf)
+{
+	bool powered;
+	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	spin_lock(&drvdata->spinlock);
+	powered = drvdata->config.hw_powered;
+	spin_unlock(&drvdata->spinlock);
+
+	return sprintf(buf, "%d\n", powered);
+}
+static DEVICE_ATTR_RO(powered);
+
+/* attribute and group sysfs tables. */
+static struct attribute *coresight_cti_attrs[] = {
+	&dev_attr_enable.attr,
+	&dev_attr_powered.attr,
+	NULL,
+};
+
+static const struct attribute_group coresight_cti_group = {
+	.attrs = coresight_cti_attrs,
+};
+
+const struct attribute_group *coresight_cti_groups[] = {
+	&coresight_cti_group,
+	NULL,
+};
diff --git a/drivers/hwtracing/coresight/coresight-cti.c b/drivers/hwtracing/coresight/coresight-cti.c
new file mode 100644
index 000000000000..c71b72d12534
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-cti.c
@@ -0,0 +1,446 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018 Linaro Limited, All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#include "coresight-cti.h"
+
+/**
+ * CTI devices can be associated with a PE, or be connected to CoreSight
+ * hardware. We have a list of all CTIs irrespective of CPU bound or
+ * otherwise.
+ *
+ * We assume that the non-CPU CTIs are always powered as we do with sinks etc.
+ *
+ * We leave the client to figure out if all the CTIs are interconnected with
+ * the same CTM, in general this is the case but does not always have to be.
+ */
+
+/* net of CTI devices connected via CTM */
+LIST_HEAD(ect_net);
+
+/* protect the list */
+static DEFINE_MUTEX(ect_mutex);
+
+#define csdev_to_cti_drvdata(csdev)	\
+	dev_get_drvdata(csdev->dev.parent)
+
+/*
+ * CTI naming. CTI bound to cores will have the name cti_cpu<N> where
+ * N is the CPU ID. System CTIs will have the name cti_sys<I> where I
+ * is an index allocated by order of discovery.
+ *
+ * CTI device name list - for CTI not bound to cores.
+ */
+DEFINE_CORESIGHT_DEVLIST(cti_sys_devs, "cti_sys");
+
+/* write set of regs to hardware - call with spinlock claimed */
+void cti_write_all_hw_regs(struct cti_drvdata *drvdata)
+{
+	struct cti_config *config = &drvdata->config;
+	int i;
+
+	CS_UNLOCK(drvdata->base);
+
+	/* disable CTI before writing registers */
+	writel_relaxed(0, drvdata->base + CTICONTROL);
+
+	/* write the CTI trigger registers */
+	for (i = 0; i < config->nr_trig_max; i++) {
+		writel_relaxed(config->ctiinen[i], drvdata->base + CTIINEN(i));
+		writel_relaxed(config->ctiouten[i],
+			       drvdata->base + CTIOUTEN(i));
+	}
+
+	/* other regs */
+	writel_relaxed(config->ctigate, drvdata->base + CTIGATE);
+	writel_relaxed(config->asicctl, drvdata->base + ASICCTL);
+	writel_relaxed(config->ctiappset, drvdata->base + CTIAPPSET);
+
+	/* re-enable CTI */
+	writel_relaxed(1, drvdata->base + CTICONTROL);
+
+	CS_LOCK(drvdata->base);
+}
+
+static void cti_enable_hw_smp_call(void *info)
+{
+	struct cti_drvdata *drvdata = info;
+
+	cti_write_all_hw_regs(drvdata);
+}
+
+/* write regs to hardware and enable */
+static int cti_enable_hw(struct cti_drvdata *drvdata)
+{
+	struct cti_config *config = &drvdata->config;
+	struct device *dev = &drvdata->csdev->dev;
+	int rc = 0;
+
+	pm_runtime_get_sync(dev->parent);
+	spin_lock(&drvdata->spinlock);
+
+	/* no need to do anything if enabled or unpowered*/
+	if (config->hw_enabled || !config->hw_powered)
+		goto cti_state_unchanged;
+
+	/* claim the device */
+	rc = coresight_claim_device(drvdata->base);
+	if (rc)
+		goto cti_err_not_enabled;
+
+	if (drvdata->ctidev.cpu >= 0) {
+		rc = smp_call_function_single(drvdata->ctidev.cpu,
+					      cti_enable_hw_smp_call,
+					      drvdata, 1);
+		if (rc)
+			goto cti_err_not_enabled;
+	} else {
+		cti_write_all_hw_regs(drvdata);
+	}
+
+	config->hw_enabled = true;
+	atomic_inc(&drvdata->config.enable_req_count);
+	spin_unlock(&drvdata->spinlock);
+	return rc;
+
+cti_state_unchanged:
+	atomic_inc(&drvdata->config.enable_req_count);
+
+	/* cannot enable due to error */
+cti_err_not_enabled:
+	spin_unlock(&drvdata->spinlock);
+	pm_runtime_put(dev->parent);
+	return rc;
+}
+
+/* disable hardware */
+static int cti_disable_hw(struct cti_drvdata *drvdata)
+{
+	struct cti_config *config = &drvdata->config;
+	struct device *dev = &drvdata->csdev->dev;
+
+	spin_lock(&drvdata->spinlock);
+
+	/* check refcount - disable on 0 */
+	if (atomic_dec_return(&drvdata->config.enable_req_count) > 0)
+		goto cti_not_disabled;
+
+	/* no need to do anything if disabled or cpu unpowered */
+	if (!config->hw_enabled || !config->hw_powered)
+		goto cti_not_disabled;
+
+	CS_UNLOCK(drvdata->base);
+
+	/* disable CTI */
+	writel_relaxed(0, drvdata->base + CTICONTROL);
+	config->hw_enabled = false;
+
+	coresight_disclaim_device_unlocked(drvdata->base);
+	CS_LOCK(drvdata->base);
+	spin_unlock(&drvdata->spinlock);
+	pm_runtime_put(dev);
+	return 0;
+
+	/* not disabled this call */
+cti_not_disabled:
+	spin_unlock(&drvdata->spinlock);
+	return 0;
+}
+
+/*
+ * Look at the HW DEVID register for some of the HW settings.
+ * DEVID[15:8] - max number of in / out triggers.
+ */
+#define CTI_DEVID_MAXTRIGS(devid_val) ((int) BMVAL(devid_val, 8, 15))
+
+/* DEVID[19:16] - number of CTM channels */
+#define CTI_DEVID_CTMCHANNELS(devid_val) ((int) BMVAL(devid_val, 16, 19))
+
+static void cti_set_default_config(struct device *dev,
+				   struct cti_drvdata *drvdata)
+{
+	struct cti_config *config = &drvdata->config;
+	u32 devid;
+
+	devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
+	config->nr_trig_max = CTI_DEVID_MAXTRIGS(devid);
+
+	/*
+	 * no current hardware should exceed this, but protect the driver
+	 * in case of fault / out of spec hw
+	 */
+	if (config->nr_trig_max > CTIINOUTEN_MAX) {
+		dev_warn_once(dev,
+			"Limiting HW MaxTrig value(%d) to driver max(%d)\n",
+			config->nr_trig_max, CTIINOUTEN_MAX);
+		config->nr_trig_max = CTIINOUTEN_MAX;
+	}
+
+	config->nr_ctm_channels = CTI_DEVID_CTMCHANNELS(devid);
+
+	/* Most regs default to 0 as zalloc'ed except...*/
+	config->trig_filter_enable = true;
+	config->ctigate = GENMASK(config->nr_ctm_channels - 1, 0);
+	atomic_set(&config->enable_req_count, 0);
+}
+
+/*
+ * Add a connection entry to the list of connections for this
+ * CTI device.
+ */
+int cti_add_connection_entry(struct device *dev, struct cti_drvdata *drvdata,
+			     struct cti_trig_con *tc,
+			     struct coresight_device *csdev,
+			     const char *assoc_dev_name)
+{
+	struct cti_device *cti_dev = &drvdata->ctidev;
+
+	tc->con_dev = csdev;
+	/*
+	 * Prefer actual associated CS device dev name to supplied value -
+	 * which is likely to be node name / other conn name.
+	 */
+	if (csdev)
+		tc->con_dev_name = dev_name(&csdev->dev);
+	else if (assoc_dev_name != NULL) {
+		tc->con_dev_name = devm_kstrdup(dev,
+						assoc_dev_name, GFP_KERNEL);
+		if (!tc->con_dev_name)
+			return -ENOMEM;
+	}
+	list_add_tail(&tc->node, &cti_dev->trig_cons);
+	cti_dev->nr_trig_con++;
+
+	/* add connection usage bit info to overall info */
+	drvdata->config.trig_in_use |= tc->con_in->used_mask;
+	drvdata->config.trig_out_use |= tc->con_out->used_mask;
+
+	return 0;
+}
+
+/* create a trigger connection with appropriately sized signal groups */
+struct cti_trig_con *cti_allocate_trig_con(struct device *dev, int in_sigs,
+					   int out_sigs)
+{
+	struct cti_trig_con *tc = NULL;
+	struct cti_trig_grp *in = NULL, *out = NULL;
+
+	tc = devm_kzalloc(dev, sizeof(struct cti_trig_con), GFP_KERNEL);
+	if (!tc)
+		return tc;
+
+	in = devm_kzalloc(dev,
+			  offsetof(struct cti_trig_grp, sig_types[in_sigs]),
+			  GFP_KERNEL);
+	if (!in)
+		return NULL;
+
+	out = devm_kzalloc(dev,
+			   offsetof(struct cti_trig_grp, sig_types[out_sigs]),
+			   GFP_KERNEL);
+	if (!out)
+		return NULL;
+
+	tc->con_in = in;
+	tc->con_out = out;
+	tc->con_in->nr_sigs = in_sigs;
+	tc->con_out->nr_sigs = out_sigs;
+	return tc;
+}
+
+/*
+ * Add a default connection if nothing else is specified.
+ * single connection based on max in/out info, no assoc device
+ */
+int cti_add_default_connection(struct device *dev, struct cti_drvdata *drvdata)
+{
+	int ret = 0;
+	int n_trigs = drvdata->config.nr_trig_max;
+	u32 n_trig_mask = GENMASK(n_trigs - 1, 0);
+	struct cti_trig_con *tc = NULL;
+
+	/*
+	 * Assume max trigs for in and out,
+	 * all used, default sig types allocated
+	 */
+	tc = cti_allocate_trig_con(dev, n_trigs, n_trigs);
+	if (!tc)
+		return -ENOMEM;
+
+	tc->con_in->used_mask = n_trig_mask;
+	tc->con_out->used_mask = n_trig_mask;
+	ret = cti_add_connection_entry(dev, drvdata, tc, NULL, "default");
+	return ret;
+}
+
+/** cti ect operations **/
+int cti_enable(struct coresight_device *csdev)
+{
+	struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
+
+	return cti_enable_hw(drvdata);
+}
+
+int cti_disable(struct coresight_device *csdev)
+{
+	struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
+
+	return cti_disable_hw(drvdata);
+}
+
+const struct coresight_ops_ect cti_ops_ect = {
+	.enable = cti_enable,
+	.disable = cti_disable,
+};
+
+const struct coresight_ops cti_ops = {
+	.ect_ops = &cti_ops_ect,
+};
+
+/*
+ * Free up CTI specific resources
+ * called by dev->release, need to call down to underlying csdev release.
+ */
+static void cti_device_release(struct device *dev)
+{
+	struct cti_drvdata *drvdata = dev_get_drvdata(dev->parent);
+	struct cti_drvdata *ect_item, *ect_tmp;
+
+	mutex_lock(&ect_mutex);
+
+	/* remove from the list */
+	list_for_each_entry_safe(ect_item, ect_tmp, &ect_net, node) {
+		if (ect_item == drvdata) {
+			list_del(&ect_item->node);
+			break;
+		}
+	}
+	mutex_unlock(&ect_mutex);
+
+	if (drvdata->csdev_release)
+		drvdata->csdev_release(dev);
+}
+
+static int cti_probe(struct amba_device *adev, const struct amba_id *id)
+{
+	int ret = 0;
+	void __iomem *base;
+	struct device *dev = &adev->dev;
+	struct cti_drvdata *drvdata = NULL;
+	struct coresight_desc cti_desc;
+	struct coresight_platform_data *pdata = NULL;
+	struct resource *res = &adev->res;
+
+	/* driver data*/
+	drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+	if (!drvdata) {
+		ret = -ENOMEM;
+		dev_info(dev, "%s, mem err\n", __func__);
+		goto err_out;
+	}
+
+	/* Validity for the resource is already checked by the AMBA core */
+	base = devm_ioremap_resource(dev, res);
+	if (IS_ERR(base)) {
+		ret = PTR_ERR(base);
+		dev_err(dev, "%s, remap err\n", __func__);
+		goto err_out;
+	}
+	drvdata->base = base;
+
+	dev_set_drvdata(dev, drvdata);
+
+	/* default CTI device info  */
+	drvdata->ctidev.cpu = -1;
+	drvdata->ctidev.nr_trig_con = 0;
+	drvdata->ctidev.ctm_id = 0;
+	INIT_LIST_HEAD(&drvdata->ctidev.trig_cons);
+
+	spin_lock_init(&drvdata->spinlock);
+
+	/* initialise CTI driver config values */
+	cti_set_default_config(dev, drvdata);
+
+	pdata = coresight_cti_get_platform_data(dev);
+	if (IS_ERR(pdata)) {
+		dev_err(dev, "coresight_cti_get_platform_data err\n");
+		ret =  PTR_ERR(pdata);
+		goto err_out;
+	}
+
+	/* default to powered - could change on PM notifications */
+	drvdata->config.hw_powered = true;
+
+	/* set up device name - will depend if cpu bound or otherwise */
+	if (drvdata->ctidev.cpu >= 0)
+		cti_desc.name = devm_kasprintf(dev, GFP_KERNEL, "cti_cpu%d",
+					       drvdata->ctidev.cpu);
+	else
+		cti_desc.name = coresight_alloc_device_name(&cti_sys_devs, dev);
+	if (!cti_desc.name) {
+		ret = -ENOMEM;
+		goto err_out;
+	}
+
+	/* set up coresight component description */
+	cti_desc.pdata = pdata;
+	cti_desc.type = CORESIGHT_DEV_TYPE_ECT;
+	cti_desc.subtype.ect_subtype = CORESIGHT_DEV_SUBTYPE_ECT_CTI;
+	cti_desc.ops = &cti_ops;
+	cti_desc.groups = coresight_cti_groups;
+	cti_desc.dev = dev;
+	drvdata->csdev = coresight_register(&cti_desc);
+	if (IS_ERR(drvdata->csdev)) {
+		ret = PTR_ERR(drvdata->csdev);
+		goto err_out;
+	}
+
+	/* add to list of CTI devices */
+	mutex_lock(&ect_mutex);
+	list_add(&drvdata->node, &ect_net);
+	mutex_unlock(&ect_mutex);
+
+	/* set up release chain */
+	drvdata->csdev_release = drvdata->csdev->dev.release;
+	drvdata->csdev->dev.release = cti_device_release;
+
+	/* all done - dec pm refcount */
+	pm_runtime_put(&adev->dev);
+	dev_info(&drvdata->csdev->dev, "CTI initialized\n");
+	return 0;
+
+err_out:
+	return ret;
+}
+
+static struct amba_cs_uci_id uci_id_cti[] = {
+	{
+		/*  CTI UCI data */
+		.devarch	= 0x47701a14, /* CTI v2 */
+		.devarch_mask	= 0xfff0ffff,
+		.devtype	= 0x00000014, /* maj(0x4-debug) min(0x1-ECT) */
+	}
+};
+
+static const struct amba_id cti_ids[] = {
+	CS_AMBA_ID(0x000bb906), /* Coresight CTI (SoC 400), C-A72, C-A57 */
+	CS_AMBA_ID(0x000bb922), /* CTI - C-A8 */
+	CS_AMBA_ID(0x000bb9a8), /* CTI - C-A53 */
+	CS_AMBA_ID(0x000bb9aa), /* CTI - C-A73 */
+	CS_AMBA_UCI_ID(0x000bb9da, uci_id_cti), /* CTI - C-A35 */
+	CS_AMBA_UCI_ID(0x000bb9ed, uci_id_cti), /* Coresight CTI (SoC 600) */
+	{ 0, 0},
+};
+
+static struct amba_driver cti_driver = {
+	.drv = {
+		.name	= "coresight-cti",
+		.owner = THIS_MODULE,
+		.suppress_bind_attrs = true,
+	},
+	.probe		= cti_probe,
+	.id_table	= cti_ids,
+};
+builtin_amba_driver(cti_driver);
diff --git a/drivers/hwtracing/coresight/coresight-cti.h b/drivers/hwtracing/coresight/coresight-cti.h
new file mode 100644
index 000000000000..d0ac90f49544
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-cti.h
@@ -0,0 +1,186 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (c) 2018 Linaro Limited, All rights reserved.
+ * Author: Mike Leach <mike.leach@linaro.org>
+ */
+
+#ifndef _CORESIGHT_CORESIGHT_CTI_H
+#define _CORESIGHT_CORESIGHT_CTI_H
+
+#include <asm/local.h>
+#include <linux/spinlock.h>
+#include "coresight-priv.h"
+
+/*
+ * Device registers
+ * 0x000 - 0x144: CTI programming and status
+ * 0xEDC - 0xEF8: CTI integration test.
+ * 0xF00 - 0xFFC: Coresight management registers.
+ */
+/* CTI programming registers */
+#define CTICONTROL		0x000
+#define CTIINTACK		0x010
+#define CTIAPPSET		0x014
+#define CTIAPPCLEAR		0x018
+#define CTIAPPPULSE		0x01C
+#define CTIINEN(n)		(0x020 + (4 * n))
+#define CTIOUTEN(n)		(0x0A0 + (4 * n))
+#define CTITRIGINSTATUS		0x130
+#define CTITRIGOUTSTATUS	0x134
+#define CTICHINSTATUS		0x138
+#define CTICHOUTSTATUS		0x13C
+#define CTIGATE			0x140
+#define ASICCTL			0x144
+/* Integration test registers */
+#define ITCHINACK		0xEDC /* WO CTI CSSoc 400 only*/
+#define ITTRIGINACK		0xEE0 /* WO CTI CSSoc 400 only*/
+#define ITCHOUT			0xEE4 /* WO RW-600 */
+#define ITTRIGOUT		0xEE8 /* WO RW-600 */
+#define ITCHOUTACK		0xEEC /* RO CTI CSSoc 400 only*/
+#define ITTRIGOUTACK		0xEF0 /* RO CTI CSSoc 400 only*/
+#define ITCHIN			0xEF4 /* RO */
+#define ITTRIGIN		0xEF8 /* RO */
+/* management registers */
+#define CTIDEVAFF0		0xFA8
+#define CTIDEVAFF1		0xFAC
+
+/*
+ * CTI CSSoc 600 has a max of 32 trigger signals per direction.
+ * CTI CSSoc 400 has 8 IO triggers - other CTIs can be impl def.
+ * Max of in and out defined in the DEVID register.
+ * - pick up actual number used from .dts parameters if present.
+ */
+#define CTIINOUTEN_MAX		32
+
+/**
+ * Group of related trigger signals
+ *
+ * @nr_sigs: number of signals in the group.
+ * @used_mask: bitmask representing the signal indexes in the group.
+ * @sig_types: array of types for the signals, length nr_sigs.
+ */
+struct cti_trig_grp {
+	int nr_sigs;
+	u32 used_mask;
+	int sig_types[];
+};
+
+/**
+ * Trigger connection - connection between a CTI and other (coresight) device
+ * lists input and output trigger signals for the device
+ *
+ * @con_in: connected CTIIN signals for the device.
+ * @con_out: connected CTIOUT signals for the device.
+ * @con_dev: coresight device connected to the CTI, NULL if not CS device
+ * @con_dev_name: name of connected device (CS or CPU)
+ * @node: entry node in list of connections.
+ */
+struct cti_trig_con {
+	struct cti_trig_grp *con_in;
+	struct cti_trig_grp *con_out;
+	struct coresight_device *con_dev;
+	const char *con_dev_name;
+	struct list_head node;
+};
+
+/**
+ * struct cti_device - description of CTI device properties.
+ *
+ * @nt_trig_con: Number of external devices connected to this device.
+ * @ctm_id: which CTM this device is connected to (by default it is
+ *          assumed there is a single CTM per SoC, ID 0).
+ * @trig_cons: list of connections to this device.
+ * @cpu: CPU ID if associated with CPU, -1 otherwise.
+ */
+struct cti_device {
+	int nr_trig_con;
+	u32 ctm_id;
+	struct list_head trig_cons;
+	int cpu;
+};
+
+/**
+ * struct cti_config - configuration of the CTI device hardware
+ *
+ * @nr_trig_max: Max number of trigger signals implemented on device.
+ *		 (max of trig_in or trig_out) - from ID register.
+ * @nr_ctm_channels: number of available CTM channels - from ID register.
+ * @enable_req_count: CTI is enabled alongside >=1 associated devices.
+ * @hw_enabled: true if hw is currently enabled.
+ * @hw_powered: true if associated cpu powered on, or no cpu.
+ * @trig_in_use: bitfield of in triggers registered as in use.
+ * @trig_out_use: bitfield of out triggers registered as in use.
+ * @trig_out_filter: bitfield of out triggers that are blocked if filter
+ *		     enabled. Typically this would be dbgreq / restart on
+ *		     a core CTI.
+ * @trig_filter_enable: 1 if filtering enabled.
+ * @xtrig_rchan_sel: channel selection for xtrigger connection show.
+ * @ctiappset: CTI Software application channel set.
+ * @ctiinout_sel: register selector for INEN and OUTEN regs.
+ * @ctiinen: enable input trigger to a channel.
+ * @ctiouten: enable output trigger from a channel.
+ * @ctigate: gate channel output from CTI to CTM.
+ * @asicctl: asic control register.
+ */
+struct cti_config {
+	/* hardware description */
+	int nr_ctm_channels;
+	int nr_trig_max;
+
+	/* cti enable control */
+	atomic_t enable_req_count;
+	bool hw_enabled;
+	bool hw_powered;
+
+	/* registered triggers and filtering */
+	u32 trig_in_use;
+	u32 trig_out_use;
+	u32 trig_out_filter;
+	bool trig_filter_enable;
+	u8 xtrig_rchan_sel;
+
+	/* cti cross trig programmable regs */
+	u32 ctiappset;
+	u8 ctiinout_sel;
+	u32 ctiinen[CTIINOUTEN_MAX];
+	u32 ctiouten[CTIINOUTEN_MAX];
+	u32 ctigate;
+	u32 asicctl;
+};
+
+/**
+ * struct cti_drvdata - specifics for the CTI device
+ * @base:	Memory mapped base address for this component..
+ * @csdev:	Standard CoreSight device information.
+ * @ctidev:	Extra information needed by the CTI/CTM framework.
+ * @spinlock:	Control data access to one at a time.
+ * @config:	Configuration data for this CTI device.
+ * @node:	List entry of this device in the list of CTI devices.
+ * @csdev_release: release function for underlying coresight_device.
+ */
+struct cti_drvdata {
+	void __iomem *base;
+	struct coresight_device	*csdev;
+	struct cti_device ctidev;
+	spinlock_t spinlock;
+	struct cti_config config;
+	struct list_head node;
+	void (*csdev_release)(struct device *dev);
+};
+
+/* private cti driver fns & vars */
+extern const struct attribute_group *coresight_cti_groups[];
+int cti_add_default_connection(struct device *dev,
+			       struct cti_drvdata *drvdata);
+int cti_add_connection_entry(struct device *dev, struct cti_drvdata *drvdata,
+			     struct cti_trig_con *tc,
+			     struct coresight_device *csdev,
+			     const char *assoc_dev_name);
+struct cti_trig_con *cti_allocate_trig_con(struct device *dev, int in_sigs,
+					   int out_sigs);
+int cti_enable(struct coresight_device *csdev);
+int cti_disable(struct coresight_device *csdev);
+struct coresight_platform_data *
+coresight_cti_get_platform_data(struct device *dev);
+
+#endif  /* _CORESIGHT_CORESIGHT_CTI_H */
diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c
index ef20f74c85fa..1a5fdf2710ff 100644
--- a/drivers/hwtracing/coresight/coresight.c
+++ b/drivers/hwtracing/coresight/coresight.c
@@ -955,6 +955,9 @@ static struct device_type coresight_dev_type[] = {
 	{
 		.name = "helper",
 	},
+	{
+		.name = "ect",
+	},
 };
 
 static void coresight_device_release(struct device *dev)