[PATCH v5 05/10] coresight: syscfg: Add API to activate and enable configurations
Mike Leach
mike.leach at linaro.org
Tue Mar 16 18:03:55 GMT 2021
Configurations are first activated, then when any coresight device is
enabled, the active configurations are checked and any matching
one is enabled.
This patch provides the activation / enable API.
Signed-off-by: Mike Leach <mike.leach at linaro.org>
---
.../hwtracing/coresight/coresight-config.h | 2 +
.../hwtracing/coresight/coresight-syscfg.c | 122 ++++++++++++++++++
.../hwtracing/coresight/coresight-syscfg.h | 8 ++
include/linux/coresight.h | 2 +
4 files changed, 134 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
index 38fd1c71eb05..f1a5957a25c9 100644
--- a/drivers/hwtracing/coresight/coresight-config.h
+++ b/drivers/hwtracing/coresight/coresight-config.h
@@ -127,6 +127,7 @@ struct cscfg_feature_desc {
* @nr_total_params: Sum of all parameters declared by used features
* @presets: Array of preset values.
* @event_ea: Extended attribute for perf event value
+ * @active_cnt: ref count for activate on this configuration.
*
*/
struct cscfg_config_desc {
@@ -139,6 +140,7 @@ struct cscfg_config_desc {
int nr_total_params;
const u64 *presets; /* nr_presets * nr_total_params */
struct dev_ext_attribute *event_ea;
+ atomic_t active_cnt;
};
/**
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c
index 03014a2142c1..c44746d6cd6d 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.c
+++ b/drivers/hwtracing/coresight/coresight-syscfg.c
@@ -284,6 +284,7 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc)
return err;
list_add(&config_desc->item, &cscfg_mgr->config_desc_list);
+ atomic_set(&config_desc->active_cnt, 0);
return 0;
}
@@ -451,6 +452,126 @@ void cscfg_unregister_csdev(struct coresight_device *csdev)
}
EXPORT_SYMBOL_GPL(cscfg_unregister_csdev);
+void cscfg_csdev_reset_feats(struct coresight_device *csdev)
+{
+ struct cscfg_feature_csdev *feat_csdev;
+
+ mutex_lock(&cscfg_csdev_mutex);
+ if (list_empty(&csdev->feature_csdev_list))
+ goto unlock_exit;
+
+ list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node)
+ cscfg_reset_feat(feat_csdev);
+
+unlock_exit:
+ mutex_unlock(&cscfg_csdev_mutex);
+}
+EXPORT_SYMBOL_GPL(cscfg_csdev_reset_feats);
+
+/**
+ * Mark a config descriptor as active.
+ * This will be seen when csdev devices are activated in the system.
+ *
+ * Selection by hash value - generated from the configuration name when it
+ * was loaded and added to the cs_etm/configurations file system for selection
+ * by perf.
+ *
+ * @cfg_hash: Hash value of the selected configuration name.
+ */
+int cscfg_activate_config(unsigned long cfg_hash)
+{
+ struct cscfg_config_desc *config_desc;
+ int err = -EINVAL;
+
+ mutex_lock(&cscfg_mutex);
+
+ list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
+ if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
+ /*
+ * increment the global active count - control changes to
+ * active configurations
+ */
+ atomic_inc(&cscfg_mgr->sys_active_cnt);
+
+ /*
+ * mark the descriptor as active so enable config on a
+ * device instance will use it
+ */
+ atomic_inc(&config_desc->active_cnt);
+
+ err = 0;
+ dev_dbg(cscfg_device(), "Activate config %s.\n", config_desc->name);
+ break;
+ }
+ }
+ mutex_unlock(&cscfg_mutex);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(cscfg_activate_config);
+
+void cscfg_deactivate_config(unsigned long cfg_hash)
+{
+ struct cscfg_config_desc *config_desc;
+
+ mutex_lock(&cscfg_mutex);
+
+ list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) {
+ if ((unsigned long)config_desc->event_ea->var == cfg_hash) {
+ atomic_dec(&config_desc->active_cnt);
+ atomic_dec(&cscfg_mgr->sys_active_cnt);
+ dev_dbg(cscfg_device(), "Deactivate config %s.\n", config_desc->name);
+ break;
+ }
+ }
+ mutex_unlock(&cscfg_mutex);
+}
+EXPORT_SYMBOL_GPL(cscfg_deactivate_config);
+
+/* Find and program any active config for the supplied device.*/
+int cscfg_csdev_enable_active_config(struct coresight_device *csdev,
+ unsigned long cfg_hash, int preset)
+{
+ struct cscfg_config_csdev *config_csdev_active = NULL, *config_csdev_item;
+ const struct cscfg_config_desc *config_desc;
+ int err = 0;
+
+ /* quickly check global count */
+ if (!atomic_read(&cscfg_mgr->sys_active_cnt))
+ return 0;
+
+ mutex_lock(&cscfg_csdev_mutex);
+ list_for_each_entry(config_csdev_item, &csdev->config_csdev_list, node) {
+ config_desc = config_csdev_item->config_desc;
+ if ((atomic_read(&config_desc->active_cnt)) &&
+ ((unsigned long)config_desc->event_ea->var == cfg_hash)) {
+ config_csdev_active = config_csdev_item;
+ break;
+ }
+ }
+ if (config_csdev_active) {
+ err = cscfg_csdev_enable_config(config_csdev_active, preset);
+ if (!err)
+ csdev->active_cscfg_ctxt = (void *)config_csdev_active;
+ }
+ mutex_unlock(&cscfg_csdev_mutex);
+ return err;
+}
+EXPORT_SYMBOL_GPL(cscfg_csdev_enable_active_config);
+
+/* save and disable the active config for the device */
+void cscfg_csdev_disable_active_config(struct coresight_device *csdev)
+{
+ struct cscfg_config_csdev *config_csdev;
+
+ mutex_lock(&cscfg_csdev_mutex);
+ config_csdev = (struct cscfg_config_csdev *)csdev->active_cscfg_ctxt;
+ if (config_csdev)
+ cscfg_csdev_disable_config(config_csdev);
+ mutex_unlock(&cscfg_csdev_mutex);
+}
+EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config);
+
/* Initialise system configuration management device. */
struct device *cscfg_device(void)
@@ -519,6 +640,7 @@ int __init cscfg_init(void)
INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list);
INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list);
INIT_LIST_HEAD(&cscfg_mgr->config_desc_list);
+ atomic_set(&cscfg_mgr->sys_active_cnt, 0);
dev_info(cscfg_device(), "CoreSight Configuration manager initialised");
return 0;
diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h
index 5bcae3b374c6..a52775890670 100644
--- a/drivers/hwtracing/coresight/coresight-syscfg.h
+++ b/drivers/hwtracing/coresight/coresight-syscfg.h
@@ -24,12 +24,14 @@
* @csdev_desc_list: List of coresight devices registered with the configuration manager.
* @feat_desc_list: List of feature descriptors to load into registered devices.
* @config_desc_list: List of system configuration descriptors to load into registered devices.
+ * @sys_active_cnt: Total number of active config descriptor references.
*/
struct cscfg_manager {
struct device dev;
struct list_head csdev_desc_list;
struct list_head feat_desc_list;
struct list_head config_desc_list;
+ atomic_t sys_active_cnt;
};
/* get reference to dev in cscfg_manager */
@@ -61,5 +63,11 @@ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,
int cscfg_register_csdev(struct coresight_device *csdev, u32 match_flags,
struct cscfg_csdev_feat_ops *ops);
void cscfg_unregister_csdev(struct coresight_device *csdev);
+int cscfg_activate_config(unsigned long cfg_hash);
+void cscfg_deactivate_config(unsigned long cfg_hash);
+void cscfg_csdev_reset_feats(struct coresight_device *csdev);
+int cscfg_csdev_enable_active_config(struct coresight_device *csdev,
+ unsigned long cfg_hash, int preset);
+void cscfg_csdev_disable_active_config(struct coresight_device *csdev);
#endif /* CORESIGHT_SYSCFG_H */
diff --git a/include/linux/coresight.h b/include/linux/coresight.h
index d0126ed326a6..a3b39ce2d6ef 100644
--- a/include/linux/coresight.h
+++ b/include/linux/coresight.h
@@ -221,6 +221,7 @@ struct coresight_sysfs_link {
* @has_conns_grp: Have added a "connections" group for sysfs links.
* @feature_csdev_list: List of complex feature programming added to the device.
* @config_csdev_list: List of system configurations added to the device.
+ * @active_cscfg_ctxt: Context information for current active system configuration.
*/
struct coresight_device {
struct coresight_platform_data *pdata;
@@ -245,6 +246,7 @@ struct coresight_device {
/* system configuration and feature lists */
struct list_head feature_csdev_list;
struct list_head config_csdev_list;
+ void *active_cscfg_ctxt;
};
/*
--
2.17.1
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