From 863981e96738983919de841ec669e157e6bdaeb0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Sun, 11 Sep 2016 04:34:46 -0300 Subject: Linux-libre 4.7.1-gnu --- drivers/hwtracing/coresight/coresight.c | 157 ++++++++++++++++++++++++-------- 1 file changed, 121 insertions(+), 36 deletions(-) (limited to 'drivers/hwtracing/coresight/coresight.c') diff --git a/drivers/hwtracing/coresight/coresight.c b/drivers/hwtracing/coresight/coresight.c index 2ea596109..d08d1ab9b 100644 --- a/drivers/hwtracing/coresight/coresight.c +++ b/drivers/hwtracing/coresight/coresight.c @@ -43,7 +43,15 @@ 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 *, sysfs_path); +static DEFINE_PER_CPU(struct list_head *, tracer_path); + +/* + * As of this writing only a single STM can be found in CS topologies. Since + * there is no way to know if we'll ever see more and what kind of + * configuration they will enact, for the time being only define a single path + * for STM. + */ +static struct list_head *stm_path; static int coresight_id_match(struct device *dev, void *data) { @@ -257,15 +265,27 @@ static void coresight_disable_source(struct coresight_device *csdev) void coresight_disable_path(struct list_head *path) { + u32 type; struct coresight_node *nd; struct coresight_device *csdev, *parent, *child; list_for_each_entry(nd, path, link) { csdev = nd->csdev; + type = csdev->type; + + /* + * ETF devices are tricky... They can be a link or a sink, + * depending on how they are configured. If an ETF has been + * "activated" it will be configured as a sink, otherwise + * go ahead with the link configuration. + */ + if (type == CORESIGHT_DEV_TYPE_LINKSINK) + type = (csdev == coresight_get_sink(path)) ? + CORESIGHT_DEV_TYPE_SINK : + CORESIGHT_DEV_TYPE_LINK; - switch (csdev->type) { + switch (type) { case CORESIGHT_DEV_TYPE_SINK: - case CORESIGHT_DEV_TYPE_LINKSINK: coresight_disable_sink(csdev); break; case CORESIGHT_DEV_TYPE_SOURCE: @@ -286,15 +306,27 @@ int coresight_enable_path(struct list_head *path, u32 mode) { int ret = 0; + u32 type; struct coresight_node *nd; struct coresight_device *csdev, *parent, *child; list_for_each_entry_reverse(nd, path, link) { csdev = nd->csdev; + type = csdev->type; - switch (csdev->type) { + /* + * ETF devices are tricky... They can be a link or a sink, + * depending on how they are configured. If an ETF has been + * "activated" it will be configured as a sink, otherwise + * go ahead with the link configuration. + */ + if (type == CORESIGHT_DEV_TYPE_LINKSINK) + type = (csdev == coresight_get_sink(path)) ? + CORESIGHT_DEV_TYPE_SINK : + CORESIGHT_DEV_TYPE_LINK; + + switch (type) { case CORESIGHT_DEV_TYPE_SINK: - case CORESIGHT_DEV_TYPE_LINKSINK: ret = coresight_enable_sink(csdev, mode); if (ret) goto err; @@ -353,7 +385,6 @@ static int _coresight_build_path(struct coresight_device *csdev, int i; bool found = false; struct coresight_node *node; - struct coresight_connection *conn; /* An activated sink has been found. Enqueue the element */ if ((csdev->type == CORESIGHT_DEV_TYPE_SINK || @@ -362,8 +393,9 @@ static int _coresight_build_path(struct coresight_device *csdev, /* Not a sink - recursively explore each port found on this element */ for (i = 0; i < csdev->nr_outport; i++) { - conn = &csdev->conns[i]; - if (_coresight_build_path(conn->child_dev, path) == 0) { + struct coresight_device *child_dev = csdev->conns[i].child_dev; + + if (child_dev && _coresight_build_path(child_dev, path) == 0) { found = true; break; } @@ -393,6 +425,7 @@ out: struct list_head *coresight_build_path(struct coresight_device *csdev) { struct list_head *path; + int rc; path = kzalloc(sizeof(struct list_head), GFP_KERNEL); if (!path) @@ -400,9 +433,10 @@ struct list_head *coresight_build_path(struct coresight_device *csdev) INIT_LIST_HEAD(path); - if (_coresight_build_path(csdev, path)) { + rc = _coresight_build_path(csdev, path); + if (rc) { kfree(path); - path = NULL; + return ERR_PTR(rc); } return path; @@ -432,24 +466,52 @@ void coresight_release_path(struct list_head *path) path = NULL; } +/** 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) { + dev_err(&csdev->dev, "wrong device subtype in %s\n", function); + return -EINVAL; + } + + return 0; +} + int coresight_enable(struct coresight_device *csdev) { - int ret = 0; - int cpu; + int cpu, ret = 0; struct list_head *path; mutex_lock(&coresight_mutex); - if (csdev->type != CORESIGHT_DEV_TYPE_SOURCE) { - ret = -EINVAL; - dev_err(&csdev->dev, "wrong device type in %s\n", __func__); + + ret = coresight_validate_source(csdev, __func__); + if (ret) goto out; - } + if (csdev->enable) goto out; path = coresight_build_path(csdev); - if (!path) { + if (IS_ERR(path)) { pr_err("building path(s) failed\n"); + ret = PTR_ERR(path); goto out; } @@ -461,15 +523,25 @@ int coresight_enable(struct coresight_device *csdev) if (ret) goto err_source; - /* - * 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(sysfs_path, cpu) = path; + switch (csdev->subtype.source_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: + stm_path = path; + break; + default: + /* We can't be here */ + break; + } out: mutex_unlock(&coresight_mutex); @@ -486,23 +558,36 @@ EXPORT_SYMBOL_GPL(coresight_enable); void coresight_disable(struct coresight_device *csdev) { - int cpu; - struct list_head *path; + int cpu, ret; + struct list_head *path = NULL; mutex_lock(&coresight_mutex); - if (csdev->type != CORESIGHT_DEV_TYPE_SOURCE) { - dev_err(&csdev->dev, "wrong device type in %s\n", __func__); + + ret = coresight_validate_source(csdev, __func__); + if (ret) goto out; - } + if (!csdev->enable) goto out; - cpu = source_ops(csdev)->cpu_id(csdev); - path = per_cpu(sysfs_path, cpu); + 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: + path = stm_path; + stm_path = NULL; + break; + default: + /* We can't be here */ + break; + } + coresight_disable_source(csdev); coresight_disable_path(path); coresight_release_path(path); - per_cpu(sysfs_path, cpu) = NULL; out: mutex_unlock(&coresight_mutex); @@ -514,7 +599,7 @@ static ssize_t enable_sink_show(struct device *dev, { struct coresight_device *csdev = to_coresight_device(dev); - return scnprintf(buf, PAGE_SIZE, "%u\n", (unsigned)csdev->activated); + return scnprintf(buf, PAGE_SIZE, "%u\n", csdev->activated); } static ssize_t enable_sink_store(struct device *dev, @@ -544,7 +629,7 @@ static ssize_t enable_source_show(struct device *dev, { struct coresight_device *csdev = to_coresight_device(dev); - return scnprintf(buf, PAGE_SIZE, "%u\n", (unsigned)csdev->enable); + return scnprintf(buf, PAGE_SIZE, "%u\n", csdev->enable); } static ssize_t enable_source_store(struct device *dev, -- cgit v1.2.3-54-g00ecf