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@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- .../hwtracing/coresight/coresight-config.h | 2 + .../hwtracing/coresight/coresight-syscfg.c | 172 ++++++++++++++++++ .../hwtracing/coresight/coresight-syscfg.h | 8 + include/linux/coresight.h | 2 + 4 files changed, 184 insertions(+)
diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 0667581822c1..25eb6c632692 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 e35f8c0ac2f8..b234e45c153f 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -283,6 +283,7 @@ 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; }
@@ -468,6 +469,176 @@ void cscfg_unregister_csdev(struct coresight_device *csdev) } EXPORT_SYMBOL_GPL(cscfg_unregister_csdev);
+/** + * cscfg_csdev_reset_feats - reset features for a CoreSight device. + * + * Resets all parameters and register values for any features loaded + * into @csdev to their default values. + * + * @csdev: The CoreSight device. + */ +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); + +/** + * cscfg_activate_config - Mark a configuration descriptor as active. + * + * This will be seen when csdev devices are enabled in the system. + * Only activated configurations can be enabled on individual devices. + * Activation protects the configuration from alteration or removal while + * active. + * + * 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. + * + * Increments the configuration descriptor active count and the global active + * count. + * + * @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); + +/** + * cscfg_deactivate_config - Mark a config descriptor as inactive. + * + * Decrement the configuration and global active counts. + * + * @cfg_hash: Hash value of the selected configuration name. + */ +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); + +/** + * cscfg_csdev_enable_active_config - Enable matching active configuration for device. + * + * Enables the configuration selected by @cfg_hash if the configuration is supported + * on the device and has been activated. + * + * If active and supported the CoreSight device @csdev will be programmed with the + * configuration, using @preset parameters. + * + * Should be called before driver hardware enable for the requested device, prior to + * programming and enabling the physical hardware. + * + * @csdev: CoreSight device to program. + * @cfg_hash: Selector for the configuration. + * @preset: Preset parameter values to use, 0 for current / default values. + */ +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); + +/** + * cscfg_csdev_disable_active_config - disable an active config on the device. + * + * Disables the active configuration on the CoreSight device @csdev. + * Disable will save the values of any registers marked in the configurations + * as save on disable. + * + * Should be called after driver hardware disable for the requested device, + * after disabling the physical hardware and reading back registers. + * + * @csdev: The CoreSight 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); + csdev->active_cscfg_ctxt = NULL; + } + mutex_unlock(&cscfg_csdev_mutex); +} +EXPORT_SYMBOL_GPL(cscfg_csdev_disable_active_config); + /* Initialise system configuration management device. */
struct device *cscfg_device(void) @@ -536,6 +707,7 @@ 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 6fb516e1b22e..a348049ee08b 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -222,6 +222,7 @@ 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; @@ -246,6 +247,7 @@ struct coresight_device { /* system configuration and feature lists */ struct list_head feature_csdev_list; struct list_head config_csdev_list; + void *active_cscfg_ctxt; };
/*