coresight: etm-perf: Update to handle configuration selection

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.

Link: https://lore.kernel.org/r/20210723165444.1048-5-mike.leach@linaro.org
Signed-off-by: Mike Leach <mike.leach@linaro.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20210818194022.379573-5-mathieu.poirier@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hwtracing/coresight/coresight-config.h b/drivers/hwtracing/coresight/coresight-config.h
index 5a39cbb..0667581 100644 (file)
--- 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 b582e92..e42ab91 100644 (file)
--- 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 29d90df..ba617fe 100644 (file)
--- 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 5e4bd86..b93f2b4 100644 (file)
--- 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"
 
 /*
@@ -275,6 +276,11 @@ 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 @@ create_dev_exit_unlock:
 
 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);
 }