@@ -8,6 +8,7 @@ menuconfig CORESIGHT
depends on OF || ACPI
select ARM_AMBA
select PERF_EVENTS
+ select CONFIGFS_FS
help
This framework provides a kernel interface for the CoreSight debug
and trace drivers to register themselves with. It's intended to build
@@ -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
new file mode 100644
@@ -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(¶m_item->group,
+ feat_desc->params_desc[i].name,
+ &cscfg_param_view_type);
+ configfs_add_default_group(¶m_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);
+}
new file mode 100644
@@ -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 */
@@ -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
@@ -286,6 +287,72 @@ 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.
*
@@ -307,6 +374,8 @@ 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);
@@ -321,6 +390,8 @@ 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);
@@ -716,6 +787,7 @@ 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);
}
@@ -729,6 +801,10 @@ 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);
@@ -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,