firmware: arm_scmi: Create debugfs files for SCMI communication debug metrics

Now that the basic support to collect the SCMI communication debug
metrics is in place, let us create debugfs files for the same so
that they are accessible to the users/debuggers.
Signed-off-by: Luke Parkin <luke.parkin@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Message-Id: <20240805131013.587016-5-sudeep.holla@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

drivers/firmware/arm_scmi/driver.c

@@ -2847,6 +2847,36 @@ static int scmi_device_request_notifier(struct notifier_block *nb,
 	return NOTIFY_OK;
 }
 
+static const char * const dbg_counter_strs[] = {
+	"sent_ok",
+	"sent_fail",
+	"sent_fail_polling_unsupported",
+	"sent_fail_channel_not_found",
+	"response_ok",
+	"notification_ok",
+	"delayed_response_ok",
+	"xfers_response_timeout",
+	"xfers_response_polled_timeout",
+	"response_polled_ok",
+	"err_msg_unexpected",
+	"err_msg_invalid",
+	"err_msg_nomem",
+	"err_protocol",
+};
+
+static void scmi_debugfs_counters_setup(struct scmi_debug_info *dbg,
+					struct dentry *trans)
+{
+	struct dentry *counters;
+	int idx;
+
+	counters = debugfs_create_dir("counters", trans);
+
+	for (idx = 0; idx < SCMI_DEBUG_COUNTERS_LAST; idx++)
+		debugfs_create_atomic_t(dbg_counter_strs[idx], 0400, counters,
+					&dbg->counters[idx]);
+}
+
 static void scmi_debugfs_common_cleanup(void *d)
 {
 	struct scmi_debug_info *dbg = d;
@@ -2913,6 +2943,9 @@ static struct scmi_debug_info *scmi_debugfs_common_setup(struct scmi_info *info)
 	debugfs_create_u32("rx_max_msg", 0400, trans,
 			   (u32 *)&info->rx_minfo.max_msg);
 
+	if (IS_ENABLED(CONFIG_ARM_SCMI_DEBUG_COUNTERS))
+		scmi_debugfs_counters_setup(dbg, trans);
+
 	dbg->top_dentry = top_dentry;
 
 	if (devm_add_action_or_reset(info->dev,