API for individual devices to register with the syscfg management system is added.

Devices register with matching information, and any features or configurations that match will be loaded into the device.

The feature and configuration loading is extended so that on load these are loaded into any currently registered devices. This allows configuration loading after devices have been registered.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- .../hwtracing/coresight/coresight-config.h | 98 +++++ .../hwtracing/coresight/coresight-syscfg.c | 338 +++++++++++++++++- .../hwtracing/coresight/coresight-syscfg.h | 19 + include/linux/coresight.h | 5 + 4 files changed, 459 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 21aa7464dcdc..685fb46ce893 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -139,4 +139,102 @@ struct cscfg_config_desc { const u64 *presets; /* nr_presets * nr_total_params */ };

+/** + * config register instance - part of a loaded feature. + * maps register values to csdev driver structures + * + * @reg_desc: value to use when setting feature on device / store for + * readback of volatile values. + * @driver_regval: pointer to internal driver element used to set the value + * in hardware. + */ +struct cscfg_regval_csdev { + struct cscfg_regval_desc reg_desc; + void *driver_regval; +}; + +/** + * config parameter instance - part of a loaded feature. + * + * @feat_csdev: parent feature + * @reg_csdev: register value updated by this parameter. + * @current_value: current value of parameter - may be set by user via + * sysfs, or modified during device operation. + * @val64: true if 64 bit value + */ +struct cscfg_parameter_csdev { + struct cscfg_feature_csdev *feat_csdev; + struct cscfg_regval_csdev *reg_csdev; + u64 current_value; + bool val64; +}; + +/** + * Feature instance loaded into a CoreSight device. + * + * When a feature is loaded into a specific device, then this structure holds + * the connections between the register / parameter values used and the + * internal data structures that are written when the feature is enabled. + * + * Since applying a feature modifies internal data structures in the device, + * then we have a reference to the device spinlock to protect access to these + * structures (@drv_spinlock). + * + * @feat_desc: pointer to the static descriptor for this feature. + * @csdev: parent CoreSight device instance. + * @node: list entry into feature list for this device. + * @drv_spinlock: device spinlock for access to driver register data. + * @nr_params: number of parameters. + * @params_csdev: current parameter values on this device + * @nr_regs: number of registers to be programmed. + * @regs_csdev: Programming details for the registers + */ +struct cscfg_feature_csdev { + const struct cscfg_feature_desc *feat_desc; + struct coresight_device *csdev; + struct list_head node; + spinlock_t *drv_spinlock; + int nr_params; + struct cscfg_parameter_csdev *params_csdev; + int nr_regs; + struct cscfg_regval_csdev *regs_csdev; +}; + +/** + * Configuration instance when loaded into a CoreSight device. + * + * The instance contains references to loaded features on this device that are + * used by the configuration. + * + * @config_desc:reference to the descriptor for this configuration + * @csdev: parent coresight device for this configuration instance. + * @enabled: true if configuration is enabled on this device. + * @node: list entry within the coresight device + * @nr_feat: Number of features on this device that are used in the + * configuration. + * @feats_csdev:references to the device features to enable. + */ +struct cscfg_config_csdev { + const struct cscfg_config_desc *config_desc; + struct coresight_device *csdev; + bool enabled; + struct list_head node; + int nr_feat; + struct cscfg_feature_csdev *feats_csdev[0]; +}; + +/** + * Coresight device operations. + * + * Registered coresight devices provide these operations to manage feature + * instances compatible with the device hardware and drivers + * + * @load_feat: Pass a feature descriptor into the device and create the + * loaded feature instance (struct cscfg_feature_csdev). + */ +struct cscfg_csdev_feat_ops { + int (*load_feat)(struct coresight_device *csdev, + struct cscfg_feature_csdev *feat_csdev); +}; + #endif /* _CORESIGHT_CORESIGHT_CONFIG_H */ diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index 417db3f92c2f..e93e62c1efbb 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -25,6 +25,199 @@ static struct cscfg_manager *cscfg_mgr;

/* load features and configuations into the lists */

+/* protect the cfg lists in the csdev instances */ +static DEFINE_MUTEX(cscfg_csdev_mutex); + +/* get name feature instance from a coresight device list of features */ +static struct cscfg_feature_csdev * +cscfg_get_feat_csdev(struct coresight_device *csdev, const char *name) +{ + struct cscfg_feature_csdev *feat_csdev = NULL; + + list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node) { + if (strcmp(feat_csdev->feat_desc->name, name) == 0) + return feat_csdev; + } + return NULL; +} + +/* allocate the device config instance - with max number of used features */ +static struct cscfg_config_csdev * +cscfg_alloc_csdev_cfg(struct coresight_device *csdev, int nr_feats) +{ + struct cscfg_config_csdev *config_csdev = NULL; + struct device *dev = csdev->dev.parent; + + /* this is being allocated using the devm for the coresight device */ + config_csdev = devm_kzalloc(dev, + offsetof(struct cscfg_config_csdev, feats_csdev[nr_feats]), + GFP_KERNEL); + if (!config_csdev) + return NULL; + + config_csdev->csdev = csdev; + return config_csdev; +} + +/* Load a config into a device if there are any feature matches between config and device */ +static int cscfg_add_csdev_cfg(struct coresight_device *csdev, + struct cscfg_config_desc *config_desc) +{ + struct cscfg_config_csdev *config_csdev = NULL; + struct cscfg_feature_csdev *feat_csdev; + int i; + + /* look at each required feature and see if it matches any feature on the device */ + for (i = 0; i < config_desc->nr_feat_refs; i++) { + /* look for a matching name */ + feat_csdev = cscfg_get_feat_csdev(csdev, config_desc->feat_ref_names[i]); + if (feat_csdev) { + /* + * At least one feature on this device matches the config + * add a config instance to the device and a reference to the feature. + */ + if (!config_csdev) { + config_csdev = cscfg_alloc_csdev_cfg(csdev, + config_desc->nr_feat_refs); + if (!config_csdev) + return -ENOMEM; + config_csdev->config_desc = config_desc; + } + config_csdev->feats_csdev[config_csdev->nr_feat++] = feat_csdev; + } + } + /* if matched features, add config to device.*/ + if (config_csdev) { + mutex_lock(&cscfg_csdev_mutex); + list_add(&config_csdev->node, &csdev->config_csdev_list); + mutex_unlock(&cscfg_csdev_mutex); + } + + return 0; +} + +/* + * Add the config to the set of registered devices - call with mutex locked. + * Iterates through devices - any device that matches one or more of the + * configuration features will load it, the others will ignore it. + */ +static int cscfg_add_cfg_to_csdevs(struct cscfg_config_desc *config_desc) +{ + struct cscfg_registered_csdev *csdev_item; + int err; + + list_for_each_entry(csdev_item, &cscfg_mgr->csdev_desc_list, item) { + err = cscfg_add_csdev_cfg(csdev_item->csdev, config_desc); + if (err) + return err; + } + return 0; +} + +/* + * Allocate a feature object for load into a csdev. + * memory allocated using the csdev->dev object using devm managed allocator. + */ +static struct cscfg_feature_csdev * +cscfg_alloc_csdev_feat(struct coresight_device *csdev, struct cscfg_feature_desc *feat_desc) +{ + struct cscfg_feature_csdev *feat_csdev = NULL; + struct device *dev = csdev->dev.parent; + int i; + + feat_csdev = devm_kzalloc(dev, sizeof(struct cscfg_feature_csdev), GFP_KERNEL); + if (!feat_csdev) + return NULL; + + /* parameters are optional - could be 0 */ + feat_csdev->nr_params = feat_desc->nr_params; + + /* + * if we need parameters, zero alloc the space here, the load routine in + * the csdev device driver will fill out some information according to + * feature descriptor. + */ + if (feat_csdev->nr_params) { + feat_csdev->params_csdev = devm_kcalloc(dev, feat_csdev->nr_params, + sizeof(struct cscfg_parameter_csdev), + GFP_KERNEL); + if (!feat_csdev->params_csdev) + return NULL; + + /* + * fill in the feature reference in the param - other fields + * handled by loader in csdev. + */ + for (i = 0; i < feat_csdev->nr_params; i++) + feat_csdev->params_csdev[i].feat_csdev = feat_csdev; + } + + /* + * Always have registers to program - again the load routine in csdev device + * will fill out according to feature descriptor and device requirements. + */ + feat_csdev->nr_regs = feat_desc->nr_regs; + feat_csdev->regs_csdev = devm_kcalloc(dev, feat_csdev->nr_regs, + sizeof(struct cscfg_regval_csdev), + GFP_KERNEL); + if (!feat_csdev->regs_csdev) + return NULL; + + /* load the feature default values */ + feat_csdev->feat_desc = feat_desc; + feat_csdev->csdev = csdev; + + return feat_csdev; +} + +/* load one feature into one coresight device */ +static int cscfg_load_feat_csdev(struct coresight_device *csdev, + struct cscfg_feature_desc *feat_desc, + struct cscfg_csdev_feat_ops *ops) +{ + struct cscfg_feature_csdev *feat_csdev; + int err; + + if (!ops->load_feat) + return -EINVAL; + + feat_csdev = cscfg_alloc_csdev_feat(csdev, feat_desc); + if (!feat_csdev) + return -ENOMEM; + + /* load the feature into the device */ + err = ops->load_feat(csdev, feat_csdev); + if (err) + return err; + + /* add to internal csdev feature list */ + mutex_lock(&cscfg_csdev_mutex); + list_add(&feat_csdev->node, &csdev->feature_csdev_list); + mutex_unlock(&cscfg_csdev_mutex); + + return 0; +} + +/* + * Add feature to any matching devices - call with mutex locked. + * Iterates through devices - any device that matches the feature will be + * called to load it. + */ +static int cscfg_add_feat_to_csdevs(struct cscfg_feature_desc *feat_desc) +{ + struct cscfg_registered_csdev *csdev_item; + int err; + + list_for_each_entry(csdev_item, &cscfg_mgr->csdev_desc_list, item) { + if (csdev_item->match_flags & feat_desc->match_flags) { + err = cscfg_load_feat_csdev(csdev_item->csdev, feat_desc, &csdev_item->ops); + if (err) + return err; + } + } + return 0; +} + /* check feature list for a named feature - call with mutex locked. */ static bool cscfg_match_list_feat(const char *name) { @@ -53,8 +246,14 @@ static int cscfg_check_feat_for_cfg(struct cscfg_config_desc *config_desc) */ static int cscfg_load_feat(struct cscfg_feature_desc *feat_desc) { - list_add(&feat_desc->item, &cscfg_mgr->feat_desc_list); + int err;

+ /* add feature to any matching registered devices */ + err = cscfg_add_feat_to_csdevs(feat_desc); + if (err) + return err; + + list_add(&feat_desc->item, &cscfg_mgr->feat_desc_list); return 0; }

@@ -71,6 +270,11 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) if (err) return err;

+ /* add config to any matching registered device */ + err = cscfg_add_cfg_to_csdevs(config_desc); + if (err) + return err; + list_add(&config_desc->item, &cscfg_mgr->config_desc_list); return 0; } @@ -125,6 +329,138 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs, } EXPORT_SYMBOL_GPL(cscfg_load_config_sets);

+/* Handle coresight device registration and add configs and features to devices */ + +/* iterate through config lists and load matching configs to device */ +static int cscfg_add_cfgs_csdev(struct coresight_device *csdev) +{ + struct cscfg_config_desc *config_desc; + int err = 0; + + list_for_each_entry(config_desc, &cscfg_mgr->config_desc_list, item) { + err = cscfg_add_csdev_cfg(csdev, config_desc); + if (err) + break; + } + return err; +} + +/* iterate through feature lists and load matching features to device */ +static int cscfg_add_feats_csdev(struct coresight_device *csdev, + u32 match_flags, + struct cscfg_csdev_feat_ops *ops) +{ + struct cscfg_feature_desc *feat_desc; + int err = 0; + + if (!ops->load_feat) + return -EINVAL; + + list_for_each_entry(feat_desc, &cscfg_mgr->feat_desc_list, item) { + if (feat_desc->match_flags & match_flags) { + err = cscfg_load_feat_csdev(csdev, feat_desc, ops); + if (err) + break; + } + } + return err; +} + +/* Add coresight device to list and copy its matching info */ +static int cscfg_list_add_csdev(struct coresight_device *csdev, + u32 match_flags, + struct cscfg_csdev_feat_ops *ops) +{ + struct cscfg_registered_csdev *csdev_item; + + /* allocate the list entry structure */ + csdev_item = kzalloc(sizeof(struct cscfg_registered_csdev), GFP_KERNEL); + if (!csdev_item) + return -ENOMEM; + + csdev_item->csdev = csdev; + csdev_item->match_flags = match_flags; + csdev_item->ops.load_feat = ops->load_feat; + list_add(&csdev_item->item, &cscfg_mgr->csdev_desc_list); + + INIT_LIST_HEAD(&csdev->feature_csdev_list); + INIT_LIST_HEAD(&csdev->config_csdev_list); + + return 0; +} + +/* remove a coresight device from the list and free data */ +static void cscfg_list_remove_csdev(struct coresight_device *csdev) +{ + struct cscfg_registered_csdev *csdev_item, *tmp; + + list_for_each_entry_safe(csdev_item, tmp, &cscfg_mgr->csdev_desc_list, item) { + if (csdev_item->csdev == csdev) { + list_del(&csdev_item->item); + kfree(csdev_item); + break; + } + } +} + +/** + * cscfg_register_csdev - register a coresight device with the syscfg manager. + * + * Registers the coresight device with the system. @match_flags used to check + * if the device is a match for registered features. Any currently registered + * configurations and features that match the device will be loaded onto it. + * + * @csdev: The coresight device to register. + * @match_flags: Matching information to load features. + * @ops: Standard operations supported by the device. + */ +int cscfg_register_csdev(struct coresight_device *csdev, + u32 match_flags, + struct cscfg_csdev_feat_ops *ops) +{ + int ret = 0; + + mutex_lock(&cscfg_mutex); + + /* add device to list of registered devices */ + ret = cscfg_list_add_csdev(csdev, match_flags, ops); + if (ret) + goto reg_csdev_unlock; + + /* now load any registered features and configs matching the device. */ + ret = cscfg_add_feats_csdev(csdev, match_flags, ops); + if (ret) { + cscfg_list_remove_csdev(csdev); + goto reg_csdev_unlock; + } + + ret = cscfg_add_cfgs_csdev(csdev); + if (ret) { + cscfg_list_remove_csdev(csdev); + goto reg_csdev_unlock; + } + + pr_info("CSCFG registered %s", dev_name(&csdev->dev)); + +reg_csdev_unlock: + mutex_unlock(&cscfg_mutex); + return ret; +} +EXPORT_SYMBOL_GPL(cscfg_register_csdev); + +/** + * cscfg_unregister_csdev - remove coresight device from syscfg manager. + * + * @csdev: Device to remove. + */ +void cscfg_unregister_csdev(struct coresight_device *csdev) +{ + mutex_lock(&cscfg_mutex); + cscfg_list_remove_csdev(csdev); + mutex_unlock(&cscfg_mutex); +} +EXPORT_SYMBOL_GPL(cscfg_unregister_csdev); + /* Initialise system configuration management device. */

struct device *cscfg_device(void) diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 18be9b58cd0b..5bcae3b374c6 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -35,6 +35,22 @@ struct cscfg_manager { /* get reference to dev in cscfg_manager */ struct device *cscfg_device(void);

+/** + * List entry for Coresight devices that are registered as supporting complex + * config operations. + * + * @csdev: The registered device. + * @match_flags: The matching type information for adding features. + * @ops: Operations supported by the registered device. + * @item: list entry. + */ +struct cscfg_registered_csdev { + struct coresight_device *csdev; + u32 match_flags; + struct cscfg_csdev_feat_ops ops; + struct list_head item; +}; + /* internal core operations for cscfg */ int __init cscfg_init(void); void cscfg_exit(void); @@ -42,5 +58,8 @@ void cscfg_exit(void); /* syscfg manager external API */ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs, struct cscfg_feature_desc **feat_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);

#endif /* CORESIGHT_SYSCFG_H */ diff --git a/include/linux/coresight.h b/include/linux/coresight.h index 85008a65e21f..6fb516e1b22e 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -220,6 +220,8 @@ struct coresight_sysfs_link { * @nr_links: number of sysfs links created to other components from this * device. These will appear in the "connections" group. * @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. */ struct coresight_device { struct coresight_platform_data *pdata; @@ -241,6 +243,9 @@ struct coresight_device { int nr_links; bool has_conns_grp; bool ect_enabled; /* true only if associated ect device is enabled */ + /* system configuration and feature lists */ + struct list_head feature_csdev_list; + struct list_head config_csdev_list; };

/*

Loaded coresight configurations are registered in the cs_etm\events sub directory. This extends the etm-perf code to handle these registrations, and the cs_syscfg driver to perform the registration on load.

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-etm-perf.c | 134 ++++++++++++++---- .../hwtracing/coresight/coresight-etm-perf.h | 8 ++ .../hwtracing/coresight/coresight-syscfg.c | 11 ++ 4 files changed, 127 insertions(+), 28 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h index 5a39cbbc38a4..0667581822c1 100644 --- a/drivers/hwtracing/coresight/coresight-config.h +++ b/drivers/hwtracing/coresight/coresight-config.h @@ -126,6 +126,7 @@ struct cscfg_feature_desc { * @nr_presets: Number of sets of presets supplied by this configuration. * @nr_total_params: Sum of all parameters declared by used features * @presets: Array of preset values. + * @event_ea: Extended attribute for perf event value * */ struct cscfg_config_desc { @@ -137,6 +138,7 @@ struct cscfg_config_desc { int nr_presets; int nr_total_params; const u64 *presets; /* nr_presets * nr_total_params */ + struct dev_ext_attribute *event_ea; };

/** diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 15310c72f89f..26b4bca156aa 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -18,8 +18,10 @@ #include <linux/types.h> #include <linux/workqueue.h>

+#include "coresight-config.h" #include "coresight-etm-perf.h" #include "coresight-priv.h" +#include "coresight-syscfg.h"

static struct pmu etm_pmu; static bool etm_perf_up; @@ -57,8 +59,13 @@ PMU_FORMAT_ATTR(contextid1, "config:" __stringify(ETM_OPT_CTXTID)); PMU_FORMAT_ATTR(contextid2, "config:" __stringify(ETM_OPT_CTXTID2)); PMU_FORMAT_ATTR(timestamp, "config:" __stringify(ETM_OPT_TS)); PMU_FORMAT_ATTR(retstack, "config:" __stringify(ETM_OPT_RETSTK)); +/* preset - if sink ID is used as a configuration selector */ +PMU_FORMAT_ATTR(preset, "config:0-3"); /* Sink ID - same for all ETMs */ PMU_FORMAT_ATTR(sinkid, "config2:0-31"); +/* config ID - set if a system configuration is selected */ +PMU_FORMAT_ATTR(configid, "config2:32-63"); +

/* * contextid always traces the "PID". The PID is in CONTEXTIDR_EL1 @@ -88,6 +95,8 @@ static struct attribute *etm_config_formats_attr[] = { &format_attr_timestamp.attr, &format_attr_retstack.attr, &format_attr_sinkid.attr, + &format_attr_preset.attr, + &format_attr_configid.attr, NULL, };

@@ -105,9 +114,19 @@ static const struct attribute_group etm_pmu_sinks_group = { .attrs = etm_config_sinks_attr, };

+static struct attribute *etm_config_events_attr[] = { + NULL, +}; + +static const struct attribute_group etm_pmu_events_group = { + .name = "events", + .attrs = etm_config_events_attr, +}; + static const struct attribute_group *etm_pmu_attr_groups[] = { &etm_pmu_format_group, &etm_pmu_sinks_group, + &etm_pmu_events_group, NULL, };

@@ -286,7 +305,7 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, INIT_WORK(&event_data->work, free_event_data);

/* First get the selected sink from user space. */ - if (event->attr.config2) { + if (event->attr.config2 & GENMASK_ULL(31, 0)) { id = (u32)event->attr.config2; sink = user_sink = coresight_get_sink_by_id(id); } @@ -658,68 +677,127 @@ static ssize_t etm_perf_sink_name_show(struct device *dev, return scnprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)(ea->var)); }

-int etm_perf_add_symlink_sink(struct coresight_device *csdev) +static struct dev_ext_attribute * +etm_perf_add_symlink_group(struct device *dev, const char *name, const char *group_name) { - int ret; + struct dev_ext_attribute *ea; unsigned long hash; - const char *name; + int ret; struct device *pmu_dev = etm_pmu.dev; - struct device *dev = &csdev->dev; - struct dev_ext_attribute *ea; - - if (csdev->type != CORESIGHT_DEV_TYPE_SINK && - csdev->type != CORESIGHT_DEV_TYPE_LINKSINK) - return -EINVAL; - - if (csdev->ea != NULL) - return -EINVAL;

if (!etm_perf_up) - return -EPROBE_DEFER; + return ERR_PTR(-EPROBE_DEFER);

ea = devm_kzalloc(dev, sizeof(*ea), GFP_KERNEL); if (!ea) - return -ENOMEM; + return ERR_PTR(-ENOMEM);

- name = dev_name(dev); - /* See function coresight_get_sink_by_id() to know where this is used */ + /* + * If this function is called adding a sink then the hash is used for + * sink selection - see function coresight_get_sink_by_id(). + * If adding a configuration then the hash is used for selection in + * cscfg_activate_config() + */ hash = hashlen_hash(hashlen_string(NULL, name));

sysfs_attr_init(&ea->attr.attr); ea->attr.attr.name = devm_kstrdup(dev, name, GFP_KERNEL); if (!ea->attr.attr.name) - return -ENOMEM; + return ERR_PTR(-ENOMEM);

ea->attr.attr.mode = 0444; - ea->attr.show = etm_perf_sink_name_show; ea->var = (unsigned long *)hash;

ret = sysfs_add_file_to_group(&pmu_dev->kobj, - &ea->attr.attr, "sinks"); + &ea->attr.attr, group_name);

- if (!ret) - csdev->ea = ea; + return ret ? ERR_PTR(ret) : ea; +}

- return ret; +int etm_perf_add_symlink_sink(struct coresight_device *csdev) +{ + const char *name; + struct device *dev = &csdev->dev; + int err = 0; + + if (csdev->type != CORESIGHT_DEV_TYPE_SINK && + csdev->type != CORESIGHT_DEV_TYPE_LINKSINK) + return -EINVAL; + + if (csdev->ea != NULL) + return -EINVAL; + + name = dev_name(dev); + csdev->ea = etm_perf_add_symlink_group(dev, name, "sinks"); + if (IS_ERR(csdev->ea)) { + err = PTR_ERR(csdev->ea); + csdev->ea = NULL; + } else + csdev->ea->attr.show = etm_perf_sink_name_show; + + return err; }

-void etm_perf_del_symlink_sink(struct coresight_device *csdev) +static void etm_perf_del_symlink_group(struct dev_ext_attribute *ea, const char *group_name) { struct device *pmu_dev = etm_pmu.dev; - struct dev_ext_attribute *ea = csdev->ea;

+ sysfs_remove_file_from_group(&pmu_dev->kobj, + &ea->attr.attr, group_name); +} + +void etm_perf_del_symlink_sink(struct coresight_device *csdev) +{ if (csdev->type != CORESIGHT_DEV_TYPE_SINK && csdev->type != CORESIGHT_DEV_TYPE_LINKSINK) return;

- if (!ea) + if (!csdev->ea) return;

- sysfs_remove_file_from_group(&pmu_dev->kobj, - &ea->attr.attr, "sinks"); + etm_perf_del_symlink_group(csdev->ea, "sinks"); csdev->ea = NULL; }

+static ssize_t etm_perf_cscfg_event_show(struct device *dev, + struct device_attribute *dattr, + char *buf) +{ + struct dev_ext_attribute *ea; + + ea = container_of(dattr, struct dev_ext_attribute, attr); + return scnprintf(buf, PAGE_SIZE, "configid=0x%lx\n", (unsigned long)(ea->var)); +} + +int etm_perf_add_symlink_cscfg(struct device *dev, struct cscfg_config_desc *config_desc) +{ + int err = 0; + + if (config_desc->event_ea != NULL) + return 0; + + config_desc->event_ea = etm_perf_add_symlink_group(dev, config_desc->name, "events"); + + /* set the show function to the custom cscfg event */ + if (!IS_ERR(config_desc->event_ea)) + config_desc->event_ea->attr.show = etm_perf_cscfg_event_show; + else { + err = PTR_ERR(config_desc->event_ea); + config_desc->event_ea = NULL; + } + + return err; +} + +void etm_perf_del_symlink_cscfg(struct cscfg_config_desc *config_desc) +{ + if (!config_desc->event_ea) + return; + + etm_perf_del_symlink_group(config_desc->event_ea, "events"); + config_desc->event_ea = NULL; +} + int __init etm_perf_init(void) { int ret; diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h index 29d90dfeba31..ba617fe2217e 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.h +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h @@ -11,6 +11,7 @@ #include "coresight-priv.h"

struct coresight_device; +struct cscfg_config_desc;

/* * In both ETMv3 and v4 the maximum number of address comparator implentable @@ -69,6 +70,9 @@ static inline void *etm_perf_sink_config(struct perf_output_handle *handle) return data->snk_config; return NULL; } +int etm_perf_add_symlink_cscfg(struct device *dev, + struct cscfg_config_desc *config_desc); +void etm_perf_del_symlink_cscfg(struct cscfg_config_desc *config_desc); #else static inline int etm_perf_symlink(struct coresight_device *csdev, bool link) { return -EINVAL; } @@ -79,6 +83,10 @@ static inline void *etm_perf_sink_config(struct perf_output_handle *handle) { return NULL; } +int etm_perf_add_symlink_cscfg(struct device *dev, + struct cscfg_config_desc *config_desc) +{ return -EINVAL; } +void etm_perf_del_symlink_cscfg(struct cscfg_config_desc *config_desc) {}

#endif /* CONFIG_CORESIGHT */

diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index c7f48d6b48f5..e35f8c0ac2f8 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -7,6 +7,7 @@ #include <linux/platform_device.h>

#include "coresight-config.h" +#include "coresight-etm-perf.h" #include "coresight-syscfg.h"

/* @@ -276,6 +277,11 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) if (err) return err;

+ /* add config to perf fs to allow selection */ + err = etm_perf_add_symlink_cscfg(cscfg_device(), config_desc); + if (err) + return err; + list_add(&config_desc->item, &cscfg_mgr->config_desc_list); return 0; } @@ -508,7 +514,12 @@ static int cscfg_create_device(void)

static void cscfg_clear_device(void) { + struct cscfg_config_desc *cfg_desc; + mutex_lock(&cscfg_mutex); + list_for_each_entry(cfg_desc, &cscfg_mgr->config_desc_list, item) { + etm_perf_del_symlink_cscfg(cfg_desc); + } device_unregister(cscfg_device()); mutex_unlock(&cscfg_mutex); }

Add calls to activate the selected configuration as perf starts and stops the tracing session.

Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Suzuki K Poulose suzuki.poulose@arm.com Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- drivers/hwtracing/coresight/coresight-etm-perf.c | 14 +++++++++++++- drivers/hwtracing/coresight/coresight-etm-perf.h | 2 ++ 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.c b/drivers/hwtracing/coresight/coresight-etm-perf.c index 26b4bca156aa..560baefdfed8 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.c +++ b/drivers/hwtracing/coresight/coresight-etm-perf.c @@ -215,6 +215,10 @@ static void free_event_data(struct work_struct *work) /* Free the sink buffers, if there are any */ free_sink_buffer(event_data);

+ /* clear any configuration we were using */ + if (event_data->cfg_hash) + cscfg_deactivate_config(event_data->cfg_hash); + for_each_cpu(cpu, mask) { struct list_head **ppath;

@@ -292,7 +296,7 @@ static bool sinks_compatible(struct coresight_device *a, static void *etm_setup_aux(struct perf_event *event, void **pages, int nr_pages, bool overwrite) { - u32 id; + u32 id, cfg_hash; int cpu = event->cpu; cpumask_t *mask; struct coresight_device *sink = NULL; @@ -310,6 +314,14 @@ static void *etm_setup_aux(struct perf_event *event, void **pages, sink = user_sink = coresight_get_sink_by_id(id); }

+ /* check if user wants a coresight configuration selected */ + cfg_hash = (u32)((event->attr.config2 & GENMASK_ULL(63, 32)) >> 32); + if (cfg_hash) { + if (cscfg_activate_config(cfg_hash)) + goto err; + event_data->cfg_hash = cfg_hash; + } + mask = &event_data->mask;

/* diff --git a/drivers/hwtracing/coresight/coresight-etm-perf.h b/drivers/hwtracing/coresight/coresight-etm-perf.h index ba617fe2217e..468f7799ab4f 100644 --- a/drivers/hwtracing/coresight/coresight-etm-perf.h +++ b/drivers/hwtracing/coresight/coresight-etm-perf.h @@ -49,12 +49,14 @@ struct etm_filters { * @work: Handle to free allocated memory outside IRQ context. * @mask: Hold the CPU(s) this event was set for. * @snk_config: The sink configuration. + * @cfg_hash: The hash id of any coresight config selected. * @path: An array of path, each slot for one CPU. */ struct etm_event_data { struct work_struct work; cpumask_t mask; void *snk_config; + u32 cfg_hash; struct list_head * __percpu *path; };

Adds configfs subsystem and attributes to the configuration manager to enable the listing of loaded configurations and features.

The default values of feature parameters can be accessed and altered from these attributes to affect all installed devices using the feature.

Signed-off-by: Mike Leach mike.leach@linaro.org --- drivers/hwtracing/coresight/Makefile | 3 +- .../coresight/coresight-syscfg-configfs.c | 396 ++++++++++++++++++ .../coresight/coresight-syscfg-configfs.h | 45 ++ .../hwtracing/coresight/coresight-syscfg.c | 76 ++++ .../hwtracing/coresight/coresight-syscfg.h | 7 + 5 files changed, 526 insertions(+), 1 deletion(-) create mode 100644 drivers/hwtracing/coresight/coresight-syscfg-configfs.c create mode 100644 drivers/hwtracing/coresight/coresight-syscfg-configfs.h

diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile index ad44f0fe3069..b6c4a48140ec 100644 --- a/drivers/hwtracing/coresight/Makefile +++ b/drivers/hwtracing/coresight/Makefile @@ -5,7 +5,8 @@ obj-$(CONFIG_CORESIGHT) += coresight.o coresight-y := coresight-core.o coresight-etm-perf.o coresight-platform.o \ coresight-sysfs.o coresight-syscfg.o coresight-config.o \ - coresight-cfg-preload.o coresight-cfg-afdo.o + coresight-cfg-preload.o coresight-cfg-afdo.o \ + coresight-syscfg-configfs.o obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o coresight-tmc-y := coresight-tmc-core.o coresight-tmc-etf.o \ coresight-tmc-etr.o diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.c b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c new file mode 100644 index 000000000000..c547816b9000 --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.c @@ -0,0 +1,396 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2020 Linaro Limited, All rights reserved. + * Author: Mike Leach mike.leach@linaro.org + */ + +#include <linux/configfs.h> + +#include "coresight-syscfg-configfs.h" + +/* create a default ci_type. */ +static inline struct config_item_type *cscfg_create_ci_type(void) +{ + struct config_item_type *ci_type; + + ci_type = devm_kzalloc(cscfg_device(), sizeof(*ci_type), GFP_KERNEL); + if (ci_type) + ci_type->ct_owner = THIS_MODULE; + + return ci_type; +} + +/* configurations sub-group */ + +/* attributes for the config view group */ +static ssize_t cscfg_cfg_description_show(struct config_item *item, char *page) +{ + struct cscfg_fs_config *fs_config = container_of(to_config_group(item), + struct cscfg_fs_config, group); + + return scnprintf(page, PAGE_SIZE, "%s", fs_config->config_desc->description); +} +CONFIGFS_ATTR_RO(cscfg_cfg_, description); + +static ssize_t cscfg_cfg_feature_refs_show(struct config_item *item, char *page) +{ + struct cscfg_fs_config *fs_config = container_of(to_config_group(item), + struct cscfg_fs_config, group); + const struct cscfg_config_desc *config_desc = fs_config->config_desc; + ssize_t ch_used = 0; + int i; + + for (i = 0; i < config_desc->nr_feat_refs; i++) + ch_used += scnprintf(page + ch_used, PAGE_SIZE - ch_used, + "%s\n", config_desc->feat_ref_names[i]); + return ch_used; +} +CONFIGFS_ATTR_RO(cscfg_cfg_, feature_refs); + +/* list preset values in order of features and params */ +static ssize_t cscfg_cfg_values_show(struct config_item *item, char *page) +{ + const struct cscfg_feature_desc *feat_desc; + const struct cscfg_config_desc *config_desc; + struct cscfg_fs_preset *fs_preset; + int i, j, val_idx, preset_idx; + ssize_t used = 0; + + fs_preset = container_of(to_config_group(item), struct cscfg_fs_preset, group); + config_desc = fs_preset->config_desc; + + if (!config_desc->nr_presets) + return 0; + + preset_idx = fs_preset->preset_num - 1; + + /* start index on the correct array line */ + val_idx = config_desc->nr_total_params * preset_idx; + + /* + * A set of presets is the sum of all params in used features, + * in order of declaration of features and params in the features + */ + for (i = 0; i < config_desc->nr_feat_refs; i++) { + feat_desc = cscfg_get_named_feat_desc(config_desc->feat_ref_names[i]); + for (j = 0; j < feat_desc->nr_params; j++) { + used += scnprintf(page + used, PAGE_SIZE - used, + "%s.%s = 0x%llx ", + feat_desc->name, + feat_desc->params_desc[j].name, + config_desc->presets[val_idx++]); + } + } + used += scnprintf(page + used, PAGE_SIZE - used, "\n"); + + return used; +} +CONFIGFS_ATTR_RO(cscfg_cfg_, values); + +static struct configfs_attribute *cscfg_config_view_attrs[] = { + &cscfg_cfg_attr_description, + &cscfg_cfg_attr_feature_refs, + NULL, +}; + +static struct config_item_type cscfg_config_view_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_config_view_attrs, +}; + +static struct configfs_attribute *cscfg_config_preset_attrs[] = { + &cscfg_cfg_attr_values, + NULL, +}; + +static struct config_item_type cscfg_config_preset_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_config_preset_attrs, +}; + +static int cscfg_add_preset_groups(struct cscfg_fs_config *cfg_view) +{ + int preset_num; + struct cscfg_fs_preset *cfg_fs_preset; + struct cscfg_config_desc *config_desc = cfg_view->config_desc; + char name[CONFIGFS_ITEM_NAME_LEN]; + + if (!config_desc->nr_presets) + return 0; + + for (preset_num = 1; preset_num <= config_desc->nr_presets; preset_num++) { + cfg_fs_preset = devm_kzalloc(cscfg_device(), + sizeof(struct cscfg_fs_preset), GFP_KERNEL); + + if (!cfg_fs_preset) + return -ENOMEM; + + snprintf(name, CONFIGFS_ITEM_NAME_LEN, "preset%d", preset_num); + cfg_fs_preset->preset_num = preset_num; + cfg_fs_preset->config_desc = cfg_view->config_desc; + config_group_init_type_name(&cfg_fs_preset->group, name, + &cscfg_config_preset_type); + configfs_add_default_group(&cfg_fs_preset->group, &cfg_view->group); + } + return 0; +} + +static struct config_group *cscfg_create_config_group(struct cscfg_config_desc *config_desc) +{ + struct cscfg_fs_config *cfg_view; + struct device *dev = cscfg_device(); + int err; + + if (!dev) + return ERR_PTR(-EINVAL); + + cfg_view = devm_kzalloc(dev, sizeof(struct cscfg_fs_config), GFP_KERNEL); + if (!cfg_view) + return ERR_PTR(-ENOMEM); + + cfg_view->config_desc = config_desc; + config_group_init_type_name(&cfg_view->group, config_desc->name, &cscfg_config_view_type); + + /* add in a preset<n> dir for each preset */ + err = cscfg_add_preset_groups(cfg_view); + if (err) + return ERR_PTR(err); + + return &cfg_view->group; +} + +/* attributes for features view */ + +static ssize_t cscfg_feat_description_show(struct config_item *item, char *page) +{ + struct cscfg_fs_feature *fs_feat = container_of(to_config_group(item), + struct cscfg_fs_feature, group); + + return scnprintf(page, PAGE_SIZE, "%s", fs_feat->feat_desc->description); +} +CONFIGFS_ATTR_RO(cscfg_feat_, description); + +static ssize_t cscfg_feat_matches_show(struct config_item *item, char *page) +{ + struct cscfg_fs_feature *fs_feat = container_of(to_config_group(item), + struct cscfg_fs_feature, group); + u32 match_flags = fs_feat->feat_desc->match_flags; + int used = 0; + + if (match_flags & CS_CFG_MATCH_CLASS_SRC_ALL) + used = scnprintf(page, PAGE_SIZE, "SRC_ALL "); + + if (match_flags & CS_CFG_MATCH_CLASS_SRC_ETM4) + used += scnprintf(page + used, PAGE_SIZE - used, "SRC_ETMV4 "); + + used += scnprintf(page + used, PAGE_SIZE - used, "\n"); + return used; +} +CONFIGFS_ATTR_RO(cscfg_feat_, matches); + +static ssize_t cscfg_feat_nr_params_show(struct config_item *item, char *page) +{ + struct cscfg_fs_feature *fs_feat = container_of(to_config_group(item), + struct cscfg_fs_feature, group); + + return scnprintf(page, PAGE_SIZE, "%d\n", fs_feat->feat_desc->nr_params); +} +CONFIGFS_ATTR_RO(cscfg_feat_, nr_params); + +/* base feature desc attrib structures */ +static struct configfs_attribute *cscfg_feature_view_attrs[] = { + &cscfg_feat_attr_description, + &cscfg_feat_attr_matches, + &cscfg_feat_attr_nr_params, + NULL, +}; + +static struct config_item_type cscfg_feature_view_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_feature_view_attrs, +}; + +static ssize_t cscfg_param_value_show(struct config_item *item, char *page) +{ + struct cscfg_fs_param *param_item = container_of(to_config_group(item), + struct cscfg_fs_param, group); + u64 value = param_item->feat_desc->params_desc[param_item->param_idx].value; + + return scnprintf(page, PAGE_SIZE, "0x%llx\n", value); +} + +static ssize_t cscfg_param_value_store(struct config_item *item, + const char *page, size_t size) +{ + struct cscfg_fs_param *param_item = container_of(to_config_group(item), + struct cscfg_fs_param, group); + struct cscfg_feature_desc *feat_desc = param_item->feat_desc; + int param_idx = param_item->param_idx; + u64 value; + int err; + + err = kstrtoull(page, 0, &value); + if (!err) + err = cscfg_update_feat_param_val(feat_desc, param_idx, value); + + return err ? err : size; +} +CONFIGFS_ATTR(cscfg_param_, value); + +static struct configfs_attribute *cscfg_param_view_attrs[] = { + &cscfg_param_attr_value, + NULL, +}; + +static struct config_item_type cscfg_param_view_type = { + .ct_owner = THIS_MODULE, + .ct_attrs = cscfg_param_view_attrs, +}; + +/* + * configfs has far less functionality provided to add attributes dynamically than sysfs, + * and the show and store fns pass the enclosing config_item so the actual attribute cannot + * be determined. Therefore we add each item as a group directory, with a value attribute. + */ +static int cscfg_create_params_group_items(struct cscfg_feature_desc *feat_desc, + struct config_group *params_group) +{ + struct device *dev = cscfg_device(); + struct cscfg_fs_param *param_item; + int i; + + /* parameter items - as groups with default_value attribute */ + for (i = 0; i < feat_desc->nr_params; i++) { + param_item = devm_kzalloc(dev, sizeof(struct cscfg_fs_param), GFP_KERNEL); + if (!param_item) + return -ENOMEM; + param_item->feat_desc = feat_desc; + param_item->param_idx = i; + config_group_init_type_name(&param_item->group, + feat_desc->params_desc[i].name, + &cscfg_param_view_type); + configfs_add_default_group(&param_item->group, params_group); + } + return 0; +} + +static struct config_group *cscfg_create_feature_group(struct cscfg_feature_desc *feat_desc) +{ + struct cscfg_fs_feature *feat_view; + struct config_item_type *params_group_type; + struct config_group *params_group = NULL; + struct device *dev = cscfg_device(); + int item_err; + + if (!dev) + return ERR_PTR(-EINVAL); + + feat_view = devm_kzalloc(dev, sizeof(struct cscfg_fs_feature), GFP_KERNEL); + if (!feat_view) + return ERR_PTR(-ENOMEM); + + if (feat_desc->nr_params) { + params_group = devm_kzalloc(dev, sizeof(struct config_group), GFP_KERNEL); + if (!params_group) + return ERR_PTR(-ENOMEM); + + params_group_type = cscfg_create_ci_type(); + if (!params_group_type) + return ERR_PTR(-ENOMEM); + } + + feat_view->feat_desc = feat_desc; + config_group_init_type_name(&feat_view->group, + feat_desc->name, + &cscfg_feature_view_type); + if (params_group) { + config_group_init_type_name(params_group, "params", params_group_type); + configfs_add_default_group(params_group, &feat_view->group); + item_err = cscfg_create_params_group_items(feat_desc, params_group); + if (item_err) + return ERR_PTR(item_err); + } + return &feat_view->group; +} + +static struct config_item_type cscfg_configs_type = { + .ct_owner = THIS_MODULE, +}; + +static struct config_group cscfg_configs_grp = { + .cg_item = { + .ci_namebuf = "configurations", + .ci_type = &cscfg_configs_type, + }, +}; + +/* add configuration to configurations group */ +int cscfg_configfs_add_config(struct cscfg_config_desc *config_desc) +{ + struct config_group *new_group; + int err; + + new_group = cscfg_create_config_group(config_desc); + if (IS_ERR(new_group)) + return PTR_ERR(new_group); + err = configfs_register_group(&cscfg_configs_grp, new_group); + return err; +} + +static struct config_item_type cscfg_features_type = { + .ct_owner = THIS_MODULE, +}; + +static struct config_group cscfg_features_grp = { + .cg_item = { + .ci_namebuf = "features", + .ci_type = &cscfg_features_type, + }, +}; + +/* add feature to features group */ +int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc) +{ + struct config_group *new_group; + int err; + + new_group = cscfg_create_feature_group(feat_desc); + if (IS_ERR(new_group)) + return PTR_ERR(new_group); + err = configfs_register_group(&cscfg_features_grp, new_group); + return err; +} + +int cscfg_configfs_init(struct cscfg_manager *cscfg_mgr) +{ + struct configfs_subsystem *subsys; + struct config_item_type *ci_type; + + if (!cscfg_mgr) + return -EINVAL; + + ci_type = cscfg_create_ci_type(); + if (!ci_type) + return -ENOMEM; + + subsys = &cscfg_mgr->cfgfs_subsys; + config_item_set_name(&subsys->su_group.cg_item, CSCFG_FS_SUBSYS_NAME); + subsys->su_group.cg_item.ci_type = ci_type; + + config_group_init(&subsys->su_group); + mutex_init(&subsys->su_mutex); + + /* Add default groups to subsystem */ + config_group_init(&cscfg_configs_grp); + configfs_add_default_group(&cscfg_configs_grp, &subsys->su_group); + + config_group_init(&cscfg_features_grp); + configfs_add_default_group(&cscfg_features_grp, &subsys->su_group); + + return configfs_register_subsystem(subsys); +} + +void cscfg_configfs_release(struct cscfg_manager *cscfg_mgr) +{ + configfs_unregister_subsystem(&cscfg_mgr->cfgfs_subsys); +} diff --git a/drivers/hwtracing/coresight/coresight-syscfg-configfs.h b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h new file mode 100644 index 000000000000..7d6ffe35ca4c --- /dev/null +++ b/drivers/hwtracing/coresight/coresight-syscfg-configfs.h @@ -0,0 +1,45 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Coresight system configuration driver - support for configfs. + */ + +#ifndef CORESIGHT_SYSCFG_CONFIGFS_H +#define CORESIGHT_SYSCFG_CONFIGFS_H + +#include <linux/configfs.h> +#include "coresight-syscfg.h" + +#define CSCFG_FS_SUBSYS_NAME "cs-syscfg" + +/* container for configuration view */ +struct cscfg_fs_config { + struct cscfg_config_desc *config_desc; + struct config_group group; +}; + +/* container for feature view */ +struct cscfg_fs_feature { + struct cscfg_feature_desc *feat_desc; + struct config_group group; +}; + +/* container for parameter view */ +struct cscfg_fs_param { + int param_idx; + struct cscfg_feature_desc *feat_desc; + struct config_group group; +}; + +/* container for preset view */ +struct cscfg_fs_preset { + int preset_num; + struct cscfg_config_desc *config_desc; + struct config_group group; +}; + +int cscfg_configfs_init(struct cscfg_manager *cscfg_mgr); +void cscfg_configfs_release(struct cscfg_manager *cscfg_mgr); +int cscfg_configfs_add_config(struct cscfg_config_desc *config_desc); +int cscfg_configfs_add_feature(struct cscfg_feature_desc *feat_desc); + +#endif /* CORESIGHT_SYSCFG_CONFIGFS_H */ diff --git a/drivers/hwtracing/coresight/coresight-syscfg.c b/drivers/hwtracing/coresight/coresight-syscfg.c index 41f742190639..180202402eb5 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.c +++ b/drivers/hwtracing/coresight/coresight-syscfg.c @@ -9,6 +9,7 @@ #include "coresight-config.h" #include "coresight-etm-perf.h" #include "coresight-syscfg.h" +#include "coresight-syscfg-configfs.h"

/* * cscfg_ API manages configurations and features for the entire coresight @@ -287,6 +288,72 @@ static int cscfg_load_config(struct cscfg_config_desc *config_desc) return 0; }

+/* get a feature descriptor by name */ +const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name) +{ + const struct cscfg_feature_desc *feat_desc = NULL, *feat_desc_item; + + mutex_lock(&cscfg_mutex); + + list_for_each_entry(feat_desc_item, &cscfg_mgr->feat_desc_list, item) { + if (strcmp(feat_desc_item->name, name) == 0) { + feat_desc = feat_desc_item; + break; + } + } + + mutex_unlock(&cscfg_mutex); + return feat_desc; +} + +/* called with cscfg_mutex held */ +static struct cscfg_feature_csdev * +cscfg_csdev_get_feat_from_desc(struct coresight_device *csdev, + struct cscfg_feature_desc *feat_desc) +{ + struct cscfg_feature_csdev *feat_csdev; + + list_for_each_entry(feat_csdev, &csdev->feature_csdev_list, node) { + if (feat_csdev->feat_desc == feat_desc) + return feat_csdev; + } + return NULL; +} + +int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc, + int param_idx, u64 value) +{ + int err = 0; + struct cscfg_feature_csdev *feat_csdev; + struct cscfg_registered_csdev *csdev_item; + + mutex_lock(&cscfg_mutex); + + /* check if any config active & return busy */ + if (atomic_read(&cscfg_mgr->sys_active_cnt)) { + err = -EBUSY; + goto unlock_exit; + } + + /* set the value */ + if ((param_idx < 0) || (param_idx >= feat_desc->nr_params)) { + err = -EINVAL; + goto unlock_exit; + } + feat_desc->params_desc[param_idx].value = value; + + /* update loaded instances.*/ + list_for_each_entry(csdev_item, &cscfg_mgr->csdev_desc_list, item) { + feat_csdev = cscfg_csdev_get_feat_from_desc(csdev_item->csdev, feat_desc); + if (feat_csdev) + feat_csdev->params_csdev[param_idx].current_value = value; + } + +unlock_exit: + mutex_unlock(&cscfg_mutex); + return err; +} + /** * cscfg_load_config_sets - API function to load feature and config sets. * @@ -308,6 +375,8 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs, if (feat_descs) { while (feat_descs[i]) { err = cscfg_load_feat(feat_descs[i]); + if (!err) + err = cscfg_configfs_add_feature(feat_descs[i]); if (err) { pr_err("coresight-syscfg: Failed to load feature %s\n", feat_descs[i]->name); @@ -322,6 +391,8 @@ int cscfg_load_config_sets(struct cscfg_config_desc **config_descs, if (config_descs) { while (config_descs[i]) { err = cscfg_load_config(config_descs[i]); + if (!err) + err = cscfg_configfs_add_config(config_descs[i]); if (err) { pr_err("coresight-syscfg: Failed to load configuration %s\n", config_descs[i]->name); @@ -691,6 +762,7 @@ static void cscfg_clear_device(void) list_for_each_entry(cfg_desc, &cscfg_mgr->config_desc_list, item) { etm_perf_del_symlink_cscfg(cfg_desc); } + cscfg_configfs_release(cscfg_mgr); device_unregister(cscfg_device()); mutex_unlock(&cscfg_mutex); } @@ -704,6 +776,10 @@ int __init cscfg_init(void) if (err) return err;

+ err = cscfg_configfs_init(cscfg_mgr); + if (err) + goto exit_err; + INIT_LIST_HEAD(&cscfg_mgr->csdev_desc_list); INIT_LIST_HEAD(&cscfg_mgr->feat_desc_list); INIT_LIST_HEAD(&cscfg_mgr->config_desc_list); diff --git a/drivers/hwtracing/coresight/coresight-syscfg.h b/drivers/hwtracing/coresight/coresight-syscfg.h index 7bb8c8e497ba..8d018efd6ead 100644 --- a/drivers/hwtracing/coresight/coresight-syscfg.h +++ b/drivers/hwtracing/coresight/coresight-syscfg.h @@ -6,6 +6,7 @@ #ifndef CORESIGHT_SYSCFG_H #define CORESIGHT_SYSCFG_H

+#include <linux/configfs.h> #include <linux/coresight.h> #include <linux/device.h>

@@ -25,6 +26,7 @@ * @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. + * @cfgfs_subsys: configfs subsystem used to manage configurations. */ struct cscfg_manager { struct device dev; @@ -32,6 +34,7 @@ struct cscfg_manager { struct list_head feat_desc_list; struct list_head config_desc_list; atomic_t sys_active_cnt; + struct configfs_subsystem cfgfs_subsys; };

/* get reference to dev in cscfg_manager */ @@ -57,6 +60,10 @@ struct cscfg_registered_csdev { int __init cscfg_init(void); void cscfg_exit(void); int cscfg_preload(void); +const struct cscfg_feature_desc *cscfg_get_named_feat_desc(const char *name); +int cscfg_update_feat_param_val(struct cscfg_feature_desc *feat_desc, + int param_idx, u64 value); +

/* syscfg manager external API */ int cscfg_load_config_sets(struct cscfg_config_desc **cfg_descs,

Adds documentation for the CoreSight System configuration manager.

Cc: Jonathan Corbet corbet@lwn.net Cc: linux-doc@vger.kernel.org Signed-off-by: Mike Leach mike.leach@linaro.org Reviewed-by: Mathieu Poirier mathieu.poirier@linaro.org --- .../trace/coresight/coresight-config.rst | 244 ++++++++++++++++++ Documentation/trace/coresight/coresight.rst | 16 ++ 2 files changed, 260 insertions(+) create mode 100644 Documentation/trace/coresight/coresight-config.rst

diff --git a/Documentation/trace/coresight/coresight-config.rst b/Documentation/trace/coresight/coresight-config.rst new file mode 100644 index 000000000000..a4e3ef295240 --- /dev/null +++ b/Documentation/trace/coresight/coresight-config.rst @@ -0,0 +1,244 @@ +.. SPDX-License-Identifier: GPL-2.0 + +====================================== +CoreSight System Configuration Manager +====================================== + + :Author: Mike Leach mike.leach@linaro.org + :Date: October 2020 + +Introduction +============ + +The CoreSight System Configuration manager is an API that allows the +programming of the CoreSight system with pre-defined configurations that +can then be easily enabled from sysfs or perf. + +Many CoreSight components can be programmed in complex ways - especially ETMs. +In addition, components can interact across the CoreSight system, often via +the cross trigger components such as CTI and CTM. These system settings can +be defined and enabled as named configurations. + + +Basic Concepts +============== + +This section introduces the basic concepts of a CoreSight system configuration. + + +Features +-------- + +A feature is a named set of programming for a CoreSight device. The programming +is device dependent, and can be defined in terms of absolute register values, +resource usage and parameter values. + +The feature is defined using a descriptor. This descriptor is used to load onto +a matching device, either when the feature is loaded into the system, or when the +CoreSight device is registered with the configuration manager. + +The load process involves interpreting the descriptor into a set of register +accesses in the driver - the resource usage and parameter descriptions +translated into appropriate register accesses. This interpretation makes it easy +and efficient for the feature to be programmed onto the device when required. + +The feature will not be active on the device until the feature is enabled, and +the device itself is enabled. When the device is enabled then enabled features +will be programmed into the device hardware. + +A feature is enabled as part of a configuration being enabled on the system. + + +Parameter Value +~~~~~~~~~~~~~~~ + +A parameter value is a named value that may be set by the user prior to the +feature being enabled that can adjust the behaviour of the operation programmed +by the feature. + +For example, this could be a count value in a programmed operation that repeats +at a given rate. When the feature is enabled then the current value of the +parameter is used in programming the device. + +The feature descriptor defines a default value for a parameter, which is used +if the user does not supply a new value. + +Users can update parameter values using the configfs API for the CoreSight +system - which is described below. + +The current value of the parameter is loaded into the device when the feature +is enabled on that device. + + +Configurations +-------------- + +A configuration defines a set of features that are to be used in a trace +session where the configuration is selected. For any trace session only one +configuration may be selected. + +The features defined may be on any type of device that is registered +to support system configuration. A configuration may select features to be +enabled on a class of devices - i.e. any ETMv4, or specific devices, e.g. a +specific CTI on the system. + +As with the feature, a descriptor is used to define the configuration. +This will define the features that must be enabled as part of the configuration +as well as any preset values that can be used to override default parameter +values. + + +Preset Values +~~~~~~~~~~~~~ + +Preset values are easily selectable sets of parameter values for the features +that the configuration uses. The number of values in a single preset set, equals +the sum of parameter values in the features used by the configuration. + +e.g. a configuration consists of 3 features, one has 2 parameters, one has +a single parameter, and another has no parameters. A single preset set will +therefore have 3 values. + +Presets are optionally defined by the configuration, up to 15 can be defined. +If no preset is selected, then the parameter values defined in the feature +are used as normal. + + +Operation +~~~~~~~~~ + +The following steps take place in the operation of a configuration. + +1) In this example, the configuration is 'autofdo', which has an + associated feature 'strobing' that works on ETMv4 CoreSight Devices. + +2) The configuration is enabled. For example 'perf' may select the + configuration as part of its command line:: + + perf record -e cs_etm/autofdo/ myapp + + which will enable the 'autofdo' configuration. + +3) perf starts tracing on the system. As each ETMv4 that perf uses for + trace is enabled, the configuration manager will check if the ETMv4 + has a feature that relates to the currently active configuration. + In this case 'strobing' is enabled & programmed into the ETMv4. + +4) When the ETMv4 is disabled, any registers marked as needing to be + saved will be read back. + +5) At the end of the perf session, the configuration will be disabled. + + +Viewing Configurations and Features +=================================== + +The set of configurations and features that are currently loaded into the +system can be viewed using the configfs API. + +Mount configfs as normal and the 'cs-syscfg' subsystem will appear:: + + $ ls /config + cs-syscfg stp-policy + +This has two sub-directories:: + + $ cd cs-syscfg/ + $ ls + configurations features + +The system has the configuration 'autofdo' built in. It may be examined as +follows:: + + $ cd configurations/ + $ ls + autofdo + $ cd autofdo/ + $ ls + description preset1 preset3 preset5 preset7 preset9 + feature_refs preset2 preset4 preset6 preset8 + $ cat description + Setup ETMs with strobing for autofdo + $ cat feature_refs + strobing + +Each preset declared has a preset<n> subdirectory declared. The values for +the preset can be examined:: + + $ cat preset1/values + strobing.window = 0x1388 strobing.period = 0x2 + $ cat preset2/values + strobing.window = 0x1388 strobing.period = 0x4 + +The features referenced by the configuration can be examined in the features +directory:: + + $ cd ../../features/strobing/ + $ ls + description matches nr_params params + $ cat description + Generate periodic trace capture windows. + parameter 'window': a number of CPU cycles (W) + parameter 'period': trace enabled for W cycles every period x W cycles + $ cat matches + SRC_ETMV4 + $ cat nr_params + 2 + +Move to the params directory to examine and adjust parameters:: + + cd params + $ ls + period window + $ cd period + $ ls + value + $ cat value + 0x2710 + # echo 15000 > value + # cat value + 0x3a98 + +Parameters adjusted in this way are reflected in all device instances that have +loaded the feature. + + +Using Configurations in perf +============================ + +The configurations loaded into the CoreSight configuration management are +also declared in the perf 'cs_etm' event infrastructure so that they can +be selected when running trace under perf:: + + $ ls /sys/devices/cs_etm + configurations format perf_event_mux_interval_ms sinks type + events nr_addr_filters power + +Key directories here are 'configurations' - which lists the loaded +configurations, and 'events' - a generic perf directory which allows +selection on the perf command line.:: + + $ ls configurations/ + autofdo + $ cat configurations/autofdo + 0xa7c3dddd + +As with the sinks entries, this provides a hash of the configuration name. +The entry in the 'events' directory uses perfs built in syntax generator +to substitute the syntax for the name when evaluating the command:: + + $ ls events/ + autofdo + $ cat events/autofdo + configid=0xa7c3dddd + +The 'autofdo' configuration may be selected on the perf command line:: + + $ perf record -e cs_etm/autofdo/u --per-thread <application> + +A preset to override the current parameter values can also be selected:: + + $ perf record -e cs_etm/autofdo,preset=1/u --per-thread <application> + +When configurations are selected in this way, then the trace sink used is +automatically selected. diff --git a/Documentation/trace/coresight/coresight.rst b/Documentation/trace/coresight/coresight.rst index 169749efd8d1..7ec656c9f0dc 100644 --- a/Documentation/trace/coresight/coresight.rst +++ b/Documentation/trace/coresight/coresight.rst @@ -619,6 +619,20 @@ A separate documentation file is provided to explain the use of these devices. (:doc:`coresight-ect`) [#fourth]_.

+CoreSight System Configuration +------------------------------ + +CoreSight components can be complex devices with many programming options. +Furthermore, components can be programmed to interact with each other across the +complete system. + +A CoreSight System Configuration manager is provided to allow these complex programming +configurations to be selected and used easily from perf and sysfs. + +See the separate document for further information. +(:doc:`coresight-config`) [#fifth]_. + + .. [#first] Documentation/ABI/testing/sysfs-bus-coresight-devices-stm

.. [#second] Documentation/trace/stm.rst @@ -626,3 +640,5 @@ A separate documentation file is provided to explain the use of these devices. .. [#third] https://github.com/Linaro/perf-opencsd

.. [#fourth] Documentation/trace/coresight/coresight-ect.rst + +.. [#fifth] Documentation/trace/coresight/coresight-config.rst