diff options
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-core.c')
-rw-r--r-- | drivers/hwtracing/coresight/coresight-core.c | 394 |
1 files changed, 4 insertions, 390 deletions
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index b8d6520d47c9..b83613e34289 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 @@ -46,12 +42,6 @@ struct coresight_node { }; /* - * 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 * it needs to look for another sync sequence. @@ -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); |