diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index af00dca8d1ac..cd254526a7dc 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2012, The Linux Foundation. All rights reserved. + * Copyright (c) 2022 Qualcomm Innovation Center, Inc. All rights reserved. */ #include @@ -37,18 +38,16 @@ 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. + * struct coresight_path - path from source to sink + * @path: Address of path list. + * @link: hook to the list. */ -static DEFINE_PER_CPU(struct list_head *, tracer_path); +struct coresight_path { + struct list_head *path; + struct list_head link; +}; -/* - * 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 LIST_HEAD(cs_active_paths); /* * When losing synchronisation a new barrier packet needs to be inserted at the @@ -355,6 +354,7 @@ static void coresight_disable_sink(struct coresight_device *csdev) return; coresight_control_assoc_ectdev(csdev, false); csdev->enable = false; + csdev->activated = false; } static int coresight_enable_link(struct coresight_device *csdev, @@ -590,6 +590,20 @@ int coresight_enable_path(struct list_head *path, u32 mode, void *sink_data) goto out; } +static struct coresight_device *coresight_get_source(struct list_head *path) +{ + struct coresight_device *csdev; + + if (!path) + return NULL; + + csdev = list_first_entry(path, struct coresight_node, link)->csdev; + if (csdev->type != CORESIGHT_DEV_TYPE_SOURCE) + return NULL; + + return csdev; +} + struct coresight_device *coresight_get_sink(struct list_head *path) { struct coresight_device *csdev; @@ -1086,9 +1100,23 @@ static int coresight_validate_source(struct coresight_device *csdev, return 0; } +static int coresight_store_path(struct list_head *path) +{ + struct coresight_path *node; + + node = kzalloc(sizeof(struct coresight_path), GFP_KERNEL); + if (!node) + return -ENOMEM; + + node->path = path; + list_add(&node->link, &cs_active_paths); + + return 0; +} + int coresight_enable(struct coresight_device *csdev) { - int cpu, ret = 0; + int ret = 0; struct coresight_device *sink; struct list_head *path; enum coresight_dev_subtype_source subtype; @@ -1133,26 +1161,9 @@ int coresight_enable(struct coresight_device *csdev) 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: - stm_path = path; - break; - default: - /* We can't be here */ - break; - } - + ret = coresight_store_path(path); + if (ret) + goto err_source; out: mutex_unlock(&coresight_mutex); return ret; @@ -1168,8 +1179,11 @@ EXPORT_SYMBOL_GPL(coresight_enable); void coresight_disable(struct coresight_device *csdev) { - int cpu, ret; + int ret; struct list_head *path = NULL; + struct coresight_path *cspath = NULL; + struct coresight_path *cspath_next = NULL; + struct coresight_device *src_csdev = NULL; mutex_lock(&coresight_mutex); @@ -1180,21 +1194,20 @@ void coresight_disable(struct coresight_device *csdev) if (!csdev->enable || !coresight_disable_source(csdev)) 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: - path = stm_path; - stm_path = NULL; - break; - default: - /* We can't be here */ - break; + list_for_each_entry_safe(cspath, cspath_next, &cs_active_paths, link) { + src_csdev = coresight_get_source(cspath->path); + if (!src_csdev) + continue; + if (src_csdev == csdev) { + path = cspath->path; + list_del(&cspath->link); + kfree(cspath); + } } + if (path == NULL) + goto out; + coresight_disable_path(path); coresight_release_path(path);