[PATCH v2 06/12] coresight: Move all sysfs code to sysfs file
From: James Clark
Date: Mon Jan 29 2024 - 10:42:43 EST
At the moment the core file contains both sysfs functionality and
core functionality, while the Perf mode is in a separate file in
coresight-etm-perf.c
Many of the functions have ambiguous names like
coresight_enable_source() which actually only work in relation to the
sysfs mode. To avoid further confusion, move everything that isn't core
functionality into the sysfs file and append _sysfs to the ambiguous
functions.
Signed-off-by: James Clark <james.clark@xxxxxxx>
---
drivers/hwtracing/coresight/coresight-core.c | 394 +-----------------
.../coresight/coresight-etm3x-core.c | 4 +-
.../coresight/coresight-etm4x-core.c | 4 +-
drivers/hwtracing/coresight/coresight-priv.h | 5 +-
drivers/hwtracing/coresight/coresight-stm.c | 4 +-
drivers/hwtracing/coresight/coresight-sysfs.c | 390 +++++++++++++++++
include/linux/coresight.h | 8 +-
7 files changed, 407 insertions(+), 402 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index e59fa9a906a3..0243b1de0315 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -9,7 +9,6 @@
#include <linux/types.h>
#include <linux/device.h>
#include <linux/io.h>
-#include <linux/idr.h>
#include <linux/err.h>
#include <linux/export.h>
#include <linux/slab.h>
@@ -25,15 +24,12 @@
#include "coresight-priv.h"
#include "coresight-syscfg.h"
-static DEFINE_MUTEX(coresight_mutex);
-static DEFINE_PER_CPU(struct coresight_device *, csdev_sink);
-
/*
- * Use IDR to map the hash of the source's device name
- * to the pointer of path for the source. The idr is for
- * the sources which aren't associated with CPU.
+ * Mutex used to lock all sysfs enable and disable actions and loading and
+ * unloading devices by the Coresight core.
*/
-static DEFINE_IDR(path_idr);
+DEFINE_MUTEX(coresight_mutex);
+static DEFINE_PER_CPU(struct coresight_device *, csdev_sink);
/**
* struct coresight_node - elements of a path, from source to sink
@@ -45,12 +41,6 @@ struct coresight_node {
struct list_head link;
};
-/*
- * When operating Coresight drivers from the sysFS interface, only a single
- * path can exist from a tracer (associated to a CPU) to a sink.
- */
-static DEFINE_PER_CPU(struct list_head *, tracer_path);
-
/*
* When losing synchronisation a new barrier packet needs to be inserted at the
* beginning of the data collected in a buffer. That way the decoder knows that
@@ -61,34 +51,6 @@ EXPORT_SYMBOL_GPL(coresight_barrier_pkt);
static const struct cti_assoc_op *cti_assoc_ops;
-ssize_t coresight_simple_show_pair(struct device *_dev,
- struct device_attribute *attr, char *buf)
-{
- struct coresight_device *csdev = container_of(_dev, struct coresight_device, dev);
- struct cs_pair_attribute *cs_attr = container_of(attr, struct cs_pair_attribute, attr);
- u64 val;
-
- pm_runtime_get_sync(_dev->parent);
- val = csdev_access_relaxed_read_pair(&csdev->access, cs_attr->lo_off, cs_attr->hi_off);
- pm_runtime_put_sync(_dev->parent);
- return sysfs_emit(buf, "0x%llx\n", val);
-}
-EXPORT_SYMBOL_GPL(coresight_simple_show_pair);
-
-ssize_t coresight_simple_show32(struct device *_dev,
- struct device_attribute *attr, char *buf)
-{
- struct coresight_device *csdev = container_of(_dev, struct coresight_device, dev);
- struct cs_off_attribute *cs_attr = container_of(attr, struct cs_off_attribute, attr);
- u64 val;
-
- pm_runtime_get_sync(_dev->parent);
- val = csdev_access_relaxed_read32(&csdev->access, cs_attr->off);
- pm_runtime_put_sync(_dev->parent);
- return sysfs_emit(buf, "0x%llx\n", val);
-}
-EXPORT_SYMBOL_GPL(coresight_simple_show32);
-
void coresight_set_cti_ops(const struct cti_assoc_op *cti_op)
{
cti_assoc_ops = cti_op;
@@ -324,29 +286,6 @@ static void coresight_disable_link(struct coresight_device *csdev,
link_ops(csdev)->disable(csdev, inconn, outconn);
}
-int coresight_enable_source(struct coresight_device *csdev, enum cs_mode mode,
- void *data)
-{
- int ret;
-
- /*
- * Comparison with CS_MODE_SYSFS works without taking any device
- * specific spinlock because the truthyness of that comparison can only
- * change with coresight_mutex held, which we already have here.
- */
- lockdep_assert_held(&coresight_mutex);
- if (local_read(&csdev->mode) != CS_MODE_SYSFS) {
- ret = source_ops(csdev)->enable(csdev, data, mode);
- if (ret)
- return ret;
- }
-
- atomic_inc(&csdev->refcnt);
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(coresight_enable_source);
-
static bool coresight_is_helper(struct coresight_device *csdev)
{
return csdev->type == CORESIGHT_DEV_TYPE_HELPER;
@@ -392,30 +331,6 @@ void coresight_disable_source(struct coresight_device *csdev, void *data)
}
EXPORT_SYMBOL_GPL(coresight_disable_source);
-/**
- * coresight_disable_source_sysfs - Drop the reference count by 1 and disable
- * the device if there are no users left.
- *
- * @csdev: The coresight device to disable
- * @data: Opaque data to pass on to the disable function of the source device.
- * For example in perf mode this is a pointer to the struct perf_event.
- *
- * Returns true if the device has been disabled.
- */
-static bool coresight_disable_source_sysfs(struct coresight_device *csdev,
- void *data)
-{
- lockdep_assert_held(&coresight_mutex);
- if (local_read(&csdev->mode) != CS_MODE_SYSFS)
- return false;
-
- if (atomic_dec_return(&csdev->refcnt) == 0) {
- coresight_disable_source(csdev, data);
- return true;
- }
- return false;
-}
-
/*
* coresight_disable_path_from : Disable components in the given path beyond
* @nd in the list. If @nd is NULL, all the components, except the SOURCE are
@@ -572,39 +487,6 @@ struct coresight_device *coresight_get_sink(struct list_head *path)
return csdev;
}
-/**
- * coresight_find_activated_sysfs_sink - returns the first sink activated via
- * sysfs using connection based search starting from the source reference.
- *
- * @csdev: Coresight source device reference
- */
-static struct coresight_device *
-coresight_find_activated_sysfs_sink(struct coresight_device *csdev)
-{
- int i;
- struct coresight_device *sink = NULL;
-
- if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
- csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
- csdev->sysfs_sink_activated)
- return csdev;
-
- /*
- * Recursively explore each port found on this element.
- */
- for (i = 0; i < csdev->pdata->nr_outconns; i++) {
- struct coresight_device *child_dev;
-
- child_dev = csdev->pdata->out_conns[i]->dest_dev;
- if (child_dev)
- sink = coresight_find_activated_sysfs_sink(child_dev);
- if (sink)
- return sink;
- }
-
- return NULL;
-}
-
static int coresight_sink_by_id(struct device *dev, const void *data)
{
struct coresight_device *csdev = to_coresight_device(dev);
@@ -1015,274 +897,6 @@ static void coresight_clear_default_sink(struct coresight_device *csdev)
}
}
-/** coresight_validate_source - make sure a source has the right credentials
- * @csdev: the device structure for a source.
- * @function: the function this was called from.
- *
- * Assumes the coresight_mutex is held.
- */
-static int coresight_validate_source(struct coresight_device *csdev,
- const char *function)
-{
- u32 type, subtype;
-
- type = csdev->type;
- subtype = csdev->subtype.source_subtype;
-
- if (type != CORESIGHT_DEV_TYPE_SOURCE) {
- dev_err(&csdev->dev, "wrong device type in %s\n", function);
- return -EINVAL;
- }
-
- if (subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_PROC &&
- subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE &&
- subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM &&
- subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS) {
- dev_err(&csdev->dev, "wrong device subtype in %s\n", function);
- return -EINVAL;
- }
-
- return 0;
-}
-
-int coresight_enable(struct coresight_device *csdev)
-{
- int cpu, ret = 0;
- struct coresight_device *sink;
- struct list_head *path;
- enum coresight_dev_subtype_source subtype;
- u32 hash;
-
- subtype = csdev->subtype.source_subtype;
-
- mutex_lock(&coresight_mutex);
-
- ret = coresight_validate_source(csdev, __func__);
- if (ret)
- goto out;
-
- /*
- * mode == SYSFS implies that it's already enabled. Don't look at the
- * refcount to determine this because we don't claim the source until
- * coresight_enable_source() so can still race with Perf mode which
- * doesn't hold coresight_mutex.
- */
- if (local_read(&csdev->mode) == CS_MODE_SYSFS) {
- /*
- * There could be multiple applications driving the software
- * source. So keep the refcount for each such user when the
- * source is already enabled.
- */
- if (subtype == CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE)
- atomic_inc(&csdev->refcnt);
- goto out;
- }
-
- sink = coresight_find_activated_sysfs_sink(csdev);
- if (!sink) {
- ret = -EINVAL;
- goto out;
- }
-
- path = coresight_build_path(csdev, sink);
- if (IS_ERR(path)) {
- pr_err("building path(s) failed\n");
- ret = PTR_ERR(path);
- goto out;
- }
-
- ret = coresight_enable_path(path, CS_MODE_SYSFS, NULL);
- if (ret)
- goto err_path;
-
- ret = coresight_enable_source(csdev, CS_MODE_SYSFS, NULL);
- if (ret)
- goto err_source;
-
- switch (subtype) {
- case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
- /*
- * When working from sysFS it is important to keep track
- * of the paths that were created so that they can be
- * undone in 'coresight_disable()'. Since there can only
- * be a single session per tracer (when working from sysFS)
- * a per-cpu variable will do just fine.
- */
- cpu = source_ops(csdev)->cpu_id(csdev);
- per_cpu(tracer_path, cpu) = path;
- break;
- case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
- case CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM:
- case CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS:
- /*
- * Use the hash of source's device name as ID
- * and map the ID to the pointer of the path.
- */
- hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
- ret = idr_alloc_u32(&path_idr, path, &hash, hash, GFP_KERNEL);
- if (ret)
- goto err_source;
- break;
- default:
- /* We can't be here */
- break;
- }
-
-out:
- mutex_unlock(&coresight_mutex);
- return ret;
-
-err_source:
- coresight_disable_path(path);
-
-err_path:
- coresight_release_path(path);
- goto out;
-}
-EXPORT_SYMBOL_GPL(coresight_enable);
-
-void coresight_disable(struct coresight_device *csdev)
-{
- int cpu, ret;
- struct list_head *path = NULL;
- u32 hash;
-
- mutex_lock(&coresight_mutex);
-
- ret = coresight_validate_source(csdev, __func__);
- if (ret)
- goto out;
-
- if (!coresight_disable_source_sysfs(csdev, NULL))
- goto out;
-
- switch (csdev->subtype.source_subtype) {
- case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
- cpu = source_ops(csdev)->cpu_id(csdev);
- path = per_cpu(tracer_path, cpu);
- per_cpu(tracer_path, cpu) = NULL;
- break;
- case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
- case CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM:
- case CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS:
- hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
- /* Find the path by the hash. */
- path = idr_find(&path_idr, hash);
- if (path == NULL) {
- pr_err("Path is not found for %s\n", dev_name(&csdev->dev));
- goto out;
- }
- idr_remove(&path_idr, hash);
- break;
- default:
- /* We can't be here */
- break;
- }
-
- coresight_disable_path(path);
- coresight_release_path(path);
-
-out:
- mutex_unlock(&coresight_mutex);
-}
-EXPORT_SYMBOL_GPL(coresight_disable);
-
-static ssize_t enable_sink_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct coresight_device *csdev = to_coresight_device(dev);
-
- return scnprintf(buf, PAGE_SIZE, "%u\n", csdev->sysfs_sink_activated);
-}
-
-static ssize_t enable_sink_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t size)
-{
- int ret;
- unsigned long val;
- struct coresight_device *csdev = to_coresight_device(dev);
-
- ret = kstrtoul(buf, 10, &val);
- if (ret)
- return ret;
-
- csdev->sysfs_sink_activated = !!val;
-
- return size;
-
-}
-static DEVICE_ATTR_RW(enable_sink);
-
-static ssize_t enable_source_show(struct device *dev,
- struct device_attribute *attr, char *buf)
-{
- struct coresight_device *csdev = to_coresight_device(dev);
-
- guard(mutex)(&coresight_mutex);
- return scnprintf(buf, PAGE_SIZE, "%u\n",
- local_read(&csdev->mode) == CS_MODE_SYSFS);
-}
-
-static ssize_t enable_source_store(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t size)
-{
- int ret = 0;
- unsigned long val;
- struct coresight_device *csdev = to_coresight_device(dev);
-
- ret = kstrtoul(buf, 10, &val);
- if (ret)
- return ret;
-
- if (val) {
- ret = coresight_enable(csdev);
- if (ret)
- return ret;
- } else {
- coresight_disable(csdev);
- }
-
- return size;
-}
-static DEVICE_ATTR_RW(enable_source);
-
-static struct attribute *coresight_sink_attrs[] = {
- &dev_attr_enable_sink.attr,
- NULL,
-};
-ATTRIBUTE_GROUPS(coresight_sink);
-
-static struct attribute *coresight_source_attrs[] = {
- &dev_attr_enable_source.attr,
- NULL,
-};
-ATTRIBUTE_GROUPS(coresight_source);
-
-static struct device_type coresight_dev_type[] = {
- {
- .name = "sink",
- .groups = coresight_sink_groups,
- },
- {
- .name = "link",
- },
- {
- .name = "linksink",
- .groups = coresight_sink_groups,
- },
- {
- .name = "source",
- .groups = coresight_source_groups,
- },
- {
- .name = "helper",
- }
-};
-/* Ensure the enum matches the names and groups */
-static_assert(ARRAY_SIZE(coresight_dev_type) == CORESIGHT_DEV_TYPE_MAX);
-
static void coresight_device_release(struct device *dev)
{
struct coresight_device *csdev = to_coresight_device(dev);
diff --git a/drivers/hwtracing/coresight/coresight-etm3x-core.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
index 29f62dfac673..a8be115636f0 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -714,7 +714,7 @@ static int etm_online_cpu(unsigned int cpu)
return 0;
if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
- coresight_enable(etmdrvdata[cpu]->csdev);
+ coresight_enable_sysfs(etmdrvdata[cpu]->csdev);
return 0;
}
@@ -924,7 +924,7 @@ static int etm_probe(struct amba_device *adev, const struct amba_id *id)
dev_info(&drvdata->csdev->dev,
"%s initialized\n", (char *)coresight_get_uci_data(id));
if (boot_enable) {
- coresight_enable(drvdata->csdev);
+ coresight_enable_sysfs(drvdata->csdev);
drvdata->boot_enable = true;
}
diff --git a/drivers/hwtracing/coresight/coresight-etm4x-core.c b/drivers/hwtracing/coresight/coresight-etm4x-core.c
index ebf55b1f67d7..3480b563981c 100644
--- a/drivers/hwtracing/coresight/coresight-etm4x-core.c
+++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c
@@ -1648,7 +1648,7 @@ static int etm4_online_cpu(unsigned int cpu)
return etm4_probe_cpu(cpu);
if (etmdrvdata[cpu]->boot_enable && !etmdrvdata[cpu]->sticky_enable)
- coresight_enable(etmdrvdata[cpu]->csdev);
+ coresight_enable_sysfs(etmdrvdata[cpu]->csdev);
return 0;
}
@@ -2096,7 +2096,7 @@ static int etm4_add_coresight_dev(struct etm4_init_arg *init_arg)
drvdata->cpu, type_name, major, minor);
if (boot_enable) {
- coresight_enable(drvdata->csdev);
+ coresight_enable_sysfs(drvdata->csdev);
drvdata->boot_enable = true;
}
diff --git a/drivers/hwtracing/coresight/coresight-priv.h b/drivers/hwtracing/coresight/coresight-priv.h
index ced5be05a527..eb365236f9a9 100644
--- a/drivers/hwtracing/coresight/coresight-priv.h
+++ b/drivers/hwtracing/coresight/coresight-priv.h
@@ -12,6 +12,9 @@
#include <linux/coresight.h>
#include <linux/pm_runtime.h>
+extern struct mutex coresight_mutex;
+extern struct device_type coresight_dev_type[];
+
/*
* Coresight management registers (0xf00-0xfcc)
* 0xfa0 - 0xfa4: Management registers in PFTv1.0
@@ -229,8 +232,6 @@ void coresight_add_helper(struct coresight_device *csdev,
void coresight_set_percpu_sink(int cpu, struct coresight_device *csdev);
struct coresight_device *coresight_get_percpu_sink(int cpu);
-int coresight_enable_source(struct coresight_device *csdev, enum cs_mode mode,
- void *data);
void coresight_disable_source(struct coresight_device *csdev, void *data);
#endif
diff --git a/drivers/hwtracing/coresight/coresight-stm.c b/drivers/hwtracing/coresight/coresight-stm.c
index 190ba569b05a..af9b21224246 100644
--- a/drivers/hwtracing/coresight/coresight-stm.c
+++ b/drivers/hwtracing/coresight/coresight-stm.c
@@ -332,7 +332,7 @@ static int stm_generic_link(struct stm_data *stm_data,
if (!drvdata || !drvdata->csdev)
return -EINVAL;
- return coresight_enable(drvdata->csdev);
+ return coresight_enable_sysfs(drvdata->csdev);
}
static void stm_generic_unlink(struct stm_data *stm_data,
@@ -343,7 +343,7 @@ static void stm_generic_unlink(struct stm_data *stm_data,
if (!drvdata || !drvdata->csdev)
return;
- coresight_disable(drvdata->csdev);
+ coresight_disable_sysfs(drvdata->csdev);
}
static phys_addr_t
diff --git a/drivers/hwtracing/coresight/coresight-sysfs.c b/drivers/hwtracing/coresight/coresight-sysfs.c
index dd78e9fcfc4d..92cdf8139f23 100644
--- a/drivers/hwtracing/coresight/coresight-sysfs.c
+++ b/drivers/hwtracing/coresight/coresight-sysfs.c
@@ -5,10 +5,400 @@
*/
#include <linux/device.h>
+#include <linux/idr.h>
#include <linux/kernel.h>
#include "coresight-priv.h"
+/*
+ * Use IDR to map the hash of the source's device name
+ * to the pointer of path for the source. The idr is for
+ * the sources which aren't associated with CPU.
+ */
+static DEFINE_IDR(path_idr);
+
+/*
+ * When operating Coresight drivers from the sysFS interface, only a single
+ * path can exist from a tracer (associated to a CPU) to a sink.
+ */
+static DEFINE_PER_CPU(struct list_head *, tracer_path);
+
+ssize_t coresight_simple_show_pair(struct device *_dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct coresight_device *csdev = container_of(_dev, struct coresight_device, dev);
+ struct cs_pair_attribute *cs_attr = container_of(attr, struct cs_pair_attribute, attr);
+ u64 val;
+
+ pm_runtime_get_sync(_dev->parent);
+ val = csdev_access_relaxed_read_pair(&csdev->access, cs_attr->lo_off, cs_attr->hi_off);
+ pm_runtime_put_sync(_dev->parent);
+ return sysfs_emit(buf, "0x%llx\n", val);
+}
+EXPORT_SYMBOL_GPL(coresight_simple_show_pair);
+
+ssize_t coresight_simple_show32(struct device *_dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct coresight_device *csdev = container_of(_dev, struct coresight_device, dev);
+ struct cs_off_attribute *cs_attr = container_of(attr, struct cs_off_attribute, attr);
+ u64 val;
+
+ pm_runtime_get_sync(_dev->parent);
+ val = csdev_access_relaxed_read32(&csdev->access, cs_attr->off);
+ pm_runtime_put_sync(_dev->parent);
+ return sysfs_emit(buf, "0x%llx\n", val);
+}
+EXPORT_SYMBOL_GPL(coresight_simple_show32);
+
+static int coresight_enable_source_sysfs(struct coresight_device *csdev,
+ enum cs_mode mode, void *data)
+{
+ int ret;
+
+ /*
+ * Comparison with CS_MODE_SYSFS works without taking any device
+ * specific spinlock because the truthyness of that comparison can only
+ * change with coresight_mutex held, which we already have here.
+ */
+ lockdep_assert_held(&coresight_mutex);
+ if (local_read(&csdev->mode) != CS_MODE_SYSFS) {
+ ret = source_ops(csdev)->enable(csdev, data, mode);
+ if (ret)
+ return ret;
+ }
+
+ atomic_inc(&csdev->refcnt);
+
+ return 0;
+}
+
+/**
+ * coresight_disable_source_sysfs - Drop the reference count by 1 and disable
+ * the device if there are no users left.
+ *
+ * @csdev: The coresight device to disable
+ * @data: Opaque data to pass on to the disable function of the source device.
+ * For example in perf mode this is a pointer to the struct perf_event.
+ *
+ * Returns true if the device has been disabled.
+ */
+static bool coresight_disable_source_sysfs(struct coresight_device *csdev,
+ void *data)
+{
+ lockdep_assert_held(&coresight_mutex);
+ if (local_read(&csdev->mode) != CS_MODE_SYSFS)
+ return false;
+
+ if (atomic_dec_return(&csdev->refcnt) == 0) {
+ coresight_disable_source(csdev, data);
+ return true;
+ }
+ return false;
+}
+
+/**
+ * coresight_find_activated_sysfs_sink - returns the first sink activated via
+ * sysfs using connection based search starting from the source reference.
+ *
+ * @csdev: Coresight source device reference
+ */
+static struct coresight_device *
+coresight_find_activated_sysfs_sink(struct coresight_device *csdev)
+{
+ int i;
+ struct coresight_device *sink = NULL;
+
+ if ((csdev->type == CORESIGHT_DEV_TYPE_SINK ||
+ csdev->type == CORESIGHT_DEV_TYPE_LINKSINK) &&
+ csdev->sysfs_sink_activated)
+ return csdev;
+
+ /*
+ * Recursively explore each port found on this element.
+ */
+ for (i = 0; i < csdev->pdata->nr_outconns; i++) {
+ struct coresight_device *child_dev;
+
+ child_dev = csdev->pdata->out_conns[i]->dest_dev;
+ if (child_dev)
+ sink = coresight_find_activated_sysfs_sink(child_dev);
+ if (sink)
+ return sink;
+ }
+
+ return NULL;
+}
+
+/** coresight_validate_source - make sure a source has the right credentials to
+ * be used via sysfs.
+ * @csdev: the device structure for a source.
+ * @function: the function this was called from.
+ *
+ * Assumes the coresight_mutex is held.
+ */
+static int coresight_validate_source_sysfs(struct coresight_device *csdev,
+ const char *function)
+{
+ u32 type, subtype;
+
+ type = csdev->type;
+ subtype = csdev->subtype.source_subtype;
+
+ if (type != CORESIGHT_DEV_TYPE_SOURCE) {
+ dev_err(&csdev->dev, "wrong device type in %s\n", function);
+ return -EINVAL;
+ }
+
+ if (subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_PROC &&
+ subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE &&
+ subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM &&
+ subtype != CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS) {
+ dev_err(&csdev->dev, "wrong device subtype in %s\n", function);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+int coresight_enable_sysfs(struct coresight_device *csdev)
+{
+ int cpu, ret = 0;
+ struct coresight_device *sink;
+ struct list_head *path;
+ enum coresight_dev_subtype_source subtype;
+ u32 hash;
+
+ subtype = csdev->subtype.source_subtype;
+
+ mutex_lock(&coresight_mutex);
+
+ ret = coresight_validate_source_sysfs(csdev, __func__);
+ if (ret)
+ goto out;
+
+ /*
+ * mode == SYSFS implies that it's already enabled. Don't look at the
+ * refcount to determine this because we don't claim the source until
+ * coresight_enable_source() so can still race with Perf mode which
+ * doesn't hold coresight_mutex.
+ */
+ if (local_read(&csdev->mode) == CS_MODE_SYSFS) {
+ /*
+ * There could be multiple applications driving the software
+ * source. So keep the refcount for each such user when the
+ * source is already enabled.
+ */
+ if (subtype == CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE)
+ atomic_inc(&csdev->refcnt);
+ goto out;
+ }
+
+ sink = coresight_find_activated_sysfs_sink(csdev);
+ if (!sink) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ path = coresight_build_path(csdev, sink);
+ if (IS_ERR(path)) {
+ pr_err("building path(s) failed\n");
+ ret = PTR_ERR(path);
+ goto out;
+ }
+
+ ret = coresight_enable_path(path, CS_MODE_SYSFS, NULL);
+ if (ret)
+ goto err_path;
+
+ ret = coresight_enable_source_sysfs(csdev, CS_MODE_SYSFS, NULL);
+ if (ret)
+ goto err_source;
+
+ switch (subtype) {
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
+ /*
+ * When working from sysFS it is important to keep track
+ * of the paths that were created so that they can be
+ * undone in 'coresight_disable()'. Since there can only
+ * be a single session per tracer (when working from sysFS)
+ * a per-cpu variable will do just fine.
+ */
+ cpu = source_ops(csdev)->cpu_id(csdev);
+ per_cpu(tracer_path, cpu) = path;
+ break;
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM:
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS:
+ /*
+ * Use the hash of source's device name as ID
+ * and map the ID to the pointer of the path.
+ */
+ hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
+ ret = idr_alloc_u32(&path_idr, path, &hash, hash, GFP_KERNEL);
+ if (ret)
+ goto err_source;
+ break;
+ default:
+ /* We can't be here */
+ break;
+ }
+
+out:
+ mutex_unlock(&coresight_mutex);
+ return ret;
+
+err_source:
+ coresight_disable_path(path);
+
+err_path:
+ coresight_release_path(path);
+ goto out;
+}
+EXPORT_SYMBOL_GPL(coresight_enable_sysfs);
+
+void coresight_disable_sysfs(struct coresight_device *csdev)
+{
+ int cpu, ret;
+ struct list_head *path = NULL;
+ u32 hash;
+
+ mutex_lock(&coresight_mutex);
+
+ ret = coresight_validate_source_sysfs(csdev, __func__);
+ if (ret)
+ goto out;
+
+ if (!coresight_disable_source_sysfs(csdev, NULL))
+ goto out;
+
+ switch (csdev->subtype.source_subtype) {
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_PROC:
+ cpu = source_ops(csdev)->cpu_id(csdev);
+ path = per_cpu(tracer_path, cpu);
+ per_cpu(tracer_path, cpu) = NULL;
+ break;
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_SOFTWARE:
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_TPDM:
+ case CORESIGHT_DEV_SUBTYPE_SOURCE_OTHERS:
+ hash = hashlen_hash(hashlen_string(NULL, dev_name(&csdev->dev)));
+ /* Find the path by the hash. */
+ path = idr_find(&path_idr, hash);
+ if (path == NULL) {
+ pr_err("Path is not found for %s\n", dev_name(&csdev->dev));
+ goto out;
+ }
+ idr_remove(&path_idr, hash);
+ break;
+ default:
+ /* We can't be here */
+ break;
+ }
+
+ coresight_disable_path(path);
+ coresight_release_path(path);
+
+out:
+ mutex_unlock(&coresight_mutex);
+}
+EXPORT_SYMBOL_GPL(coresight_disable_sysfs);
+
+static ssize_t enable_sink_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct coresight_device *csdev = to_coresight_device(dev);
+
+ return scnprintf(buf, PAGE_SIZE, "%u\n", csdev->sysfs_sink_activated);
+}
+
+static ssize_t enable_sink_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret;
+ unsigned long val;
+ struct coresight_device *csdev = to_coresight_device(dev);
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ csdev->sysfs_sink_activated = !!val;
+
+ return size;
+
+}
+static DEVICE_ATTR_RW(enable_sink);
+
+static ssize_t enable_source_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct coresight_device *csdev = to_coresight_device(dev);
+
+ guard(mutex)(&coresight_mutex);
+ return scnprintf(buf, PAGE_SIZE, "%u\n",
+ local_read(&csdev->mode) == CS_MODE_SYSFS);
+}
+
+static ssize_t enable_source_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t size)
+{
+ int ret = 0;
+ unsigned long val;
+ struct coresight_device *csdev = to_coresight_device(dev);
+
+ ret = kstrtoul(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ if (val) {
+ ret = coresight_enable_sysfs(csdev);
+ if (ret)
+ return ret;
+ } else {
+ coresight_disable_sysfs(csdev);
+ }
+
+ return size;
+}
+static DEVICE_ATTR_RW(enable_source);
+
+static struct attribute *coresight_sink_attrs[] = {
+ &dev_attr_enable_sink.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(coresight_sink);
+
+static struct attribute *coresight_source_attrs[] = {
+ &dev_attr_enable_source.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(coresight_source);
+
+struct device_type coresight_dev_type[] = {
+ {
+ .name = "sink",
+ .groups = coresight_sink_groups,
+ },
+ {
+ .name = "link",
+ },
+ {
+ .name = "linksink",
+ .groups = coresight_sink_groups,
+ },
+ {
+ .name = "source",
+ .groups = coresight_source_groups,
+ },
+ {
+ .name = "helper",
+ }
+};
+/* Ensure the enum matches the names and groups */
+static_assert(ARRAY_SIZE(coresight_dev_type) == CORESIGHT_DEV_TYPE_MAX);
+
/*
* Connections group - links attribute.
* Count of created links between coresight components in the group.
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index 46e6667f72ce..e8dd0df98881 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -578,8 +578,8 @@ static inline bool coresight_is_percpu_sink(struct coresight_device *csdev)
extern struct coresight_device *
coresight_register(struct coresight_desc *desc);
extern void coresight_unregister(struct coresight_device *csdev);
-extern int coresight_enable(struct coresight_device *csdev);
-extern void coresight_disable(struct coresight_device *csdev);
+extern int coresight_enable_sysfs(struct coresight_device *csdev);
+extern void coresight_disable_sysfs(struct coresight_device *csdev);
extern int coresight_timeout(struct csdev_access *csa, u32 offset,
int position, int value);
@@ -609,8 +609,8 @@ static inline struct coresight_device *
coresight_register(struct coresight_desc *desc) { return NULL; }
static inline void coresight_unregister(struct coresight_device *csdev) {}
static inline int
-coresight_enable(struct coresight_device *csdev) { return -ENOSYS; }
-static inline void coresight_disable(struct coresight_device *csdev) {}
+coresight_enable_sysfs(struct coresight_device *csdev) { return -ENOSYS; }
+static inline void coresight_disable_sysfs(struct coresight_device *csdev) {}
static inline int coresight_timeout(struct csdev_access *csa, u32 offset,
int position, int value)
--
2.34.1