--- /dev/null
+Intel(R) Trace Hub (TH)
+=======================
+
+Overview
+--------
+
+Intel(R) Trace Hub (TH) is a set of hardware blocks 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. For more information on the hardware, see Intel(R) Trace
+Hub developer's manual [1].
+
+It consists of trace sources, trace destinations (outputs) and a
+switch (Global Trace Hub, GTH). These devices are placed on a bus of
+their own ("intel_th"), where they can be discovered and configured
+via sysfs attributes.
+
+Currently, the following Intel TH subdevices (blocks) are supported:
+ - Software Trace Hub (STH), trace source, which is a System Trace
+ Module (STM) device,
+ - Memory Storage Unit (MSU), trace output, which allows storing
+ trace hub output in system memory,
+ - Parallel Trace Interface output (PTI), trace output to an external
+ debug host via a PTI port,
+ - Global Trace Hub (GTH), which is a switch and a central component
+ of Intel(R) Trace Hub architecture.
+
+Common attributes for output devices are described in
+Documentation/ABI/testing/sysfs-bus-intel_th-output-devices, the most
+notable of them is "active", which enables or disables trace output
+into that particular output device.
+
+GTH allows directing different STP masters into different output ports
+via its "masters" attribute group. More detailed GTH interface
+description is at Documentation/ABI/testing/sysfs-bus-intel_th-devices-gth.
+
+STH registers an stm class device, through which it provides interface
+to userspace and kernelspace software trace sources. See
+Documentation/tracing/stm.txt for more information on that.
+
+MSU can be configured to collect trace data into a system memory
+buffer, which can later on be read from its device nodes via read() or
+mmap() interface.
+
+On the whole, Intel(R) Trace Hub does not require any special
+userspace software to function; everything can be configured, started
+and collected via sysfs attributes, and device nodes.
+
+[1] https://software.intel.com/sites/default/files/managed/d3/3c/intel-th-developer-manual.pdf
+
+Bus and Subdevices
+------------------
+
+For each Intel TH device in the system a bus of its own is
+created and assigned an id number that reflects the order in which TH
+devices were emumerated. All TH subdevices (devices on intel_th bus)
+begin with this id: 0-gth, 0-msc0, 0-msc1, 0-pti, 0-sth, which is
+followed by device's name and an optional index.
+
+Output devices also get a device node in /dev/intel_thN, where N is
+the Intel TH device id. For example, MSU's memory buffers, when
+allocated, are accessible via /dev/intel_th0/msc{0,1}.
+
+Quick example
+-------------
+
+# figure out which GTH port is the first memory controller:
+
+$ cat /sys/bus/intel_th/devices/0-msc0/port
+0
+
+# looks like it's port 0, configure master 33 to send data to port 0:
+
+$ echo 0 > /sys/bus/intel_th/devices/0-gth/masters/33
+
+# allocate a 2-windowed multiblock buffer on the first memory
+# controller, each with 64 pages:
+
+$ echo multi > /sys/bus/intel_th/devices/0-msc0/mode
+$ echo 64,64 > /sys/bus/intel_th/devices/0-msc0/nr_pages
+
+# enable wrapping for this controller, too:
+
+$ echo 1 > /sys/bus/intel_th/devices/0-msc0/wrap
+
+# and enable tracing into this port:
+
+$ echo 1 > /sys/bus/intel_th/devices/0-msc0/active
+
+# .. send data to master 33, see stm.txt for more details ..
+# .. wait for traces to pile up ..
+# .. and stop the trace:
+
+$ echo 0 > /sys/bus/intel_th/devices/0-msc0/active
+
+# and now you can collect the trace from the device node:
+
+$ cat /dev/intel_th0/msc0 > my_stp_trace
--- /dev/null
+/*
+ * 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>");
--- /dev/null
+/*
+ * 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