From patchwork Tue Dec 12 15:54:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: James Clark X-Patchwork-Id: 13489564 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id BA954C4332F for ; Tue, 12 Dec 2023 15:56:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LR/rBxVCCS1OVFpM0FGiY6kmK2hmj3dpSQMlZhQPiWQ=; b=CHz3OacrQh2Ut/ 3/mETzBq6JwD5qtdaxpu7rQ1hJArPGoLMHnjbfWi6BnR4DYk6G12JpUSGJBtGQ6m2f47Bp+6csqoc AGcRTbkHUZEagJvyJfzN5thzMS8bsk2bYjCdkcQvCV6EwmQv9vIRjOIrowlTf2xwtFrmkT1LDjrhN DFdsQbEfJPARzCKtIJN0lWBj+YX/jIvhyUDx7rSjyjNCXdscEyJAyKnhMADiMcb+UY5xGT3NGlqrk Oi1GrmcvFcAx6iA6Q+Ri+lT/9MzT19gRWe3rbW9YhJP6sGBgitwqkh1AEvk/7cV+lDa/4rZa3IgiA pCaqtfQpMOKqOhUsKbiQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rD56f-00C8IK-1M; Tue, 12 Dec 2023 15:55:37 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1rD56X-00C8Eg-2K for linux-arm-kernel@lists.infradead.org; Tue, 12 Dec 2023 15:55:33 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 68F98143D; Tue, 12 Dec 2023 07:56:15 -0800 (PST) Received: from e127643.broadband (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 77E793F738; Tue, 12 Dec 2023 07:55:27 -0800 (PST) From: James Clark To: coresight@lists.linaro.org, suzuki.poulose@arm.com Cc: James Clark , Mike Leach , Alexander Shishkin , Maxime Coquelin , Alexandre Torgue , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com Subject: [PATCH 6/8] coresight: Move all sysfs code to sysfs file Date: Tue, 12 Dec 2023 15:54:03 +0000 Message-Id: <20231212155407.1429121-7-james.clark@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231212155407.1429121-1-james.clark@arm.com> References: <20231212155407.1429121-1-james.clark@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231212_075529_910001_C769B1E4 X-CRM114-Status: GOOD ( 35.30 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 --- 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 1d0bd1586590..eb72cdd1a273 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -9,7 +9,6 @@ #include #include #include -#include #include #include #include @@ -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 ce1995a2827f..cbb4ac8be133 100644 --- a/drivers/hwtracing/coresight/coresight-etm4x-core.c +++ b/drivers/hwtracing/coresight/coresight-etm4x-core.c @@ -1650,7 +1650,7 @@ 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; } @@ -2098,7 +2098,7 @@ 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 #include +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 +#include #include #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)