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-rw-r--r--drivers/hwtracing/intel_th/Kconfig24
-rw-r--r--drivers/hwtracing/intel_th/Makefile3
-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/intel_th.h244
6 files changed, 1033 insertions, 0 deletions
diff --git a/drivers/hwtracing/intel_th/Kconfig b/drivers/hwtracing/intel_th/Kconfig
new file mode 100644
index 000000000000..0cb01ee9090e
--- /dev/null
+++ b/drivers/hwtracing/intel_th/Kconfig
@@ -0,0 +1,24 @@
+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_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..dfd7906462da
--- /dev/null
+++ b/drivers/hwtracing/intel_th/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_INTEL_TH)		+= intel_th.o
+intel_th-y			:= core.o
+intel_th-$(CONFIG_INTEL_TH_DEBUG) += debug.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/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