remoteproc: sysmon: Add ability to send type of notification

Current implementation of the sysmon driver does not support adding
notifications for other remoteproc events - prepare, start, unprepare.
Clients on the remoteproc side might be interested in knowing when a
remoteproc boots up. This change adds the ability to send the notification
type along with the name. For example, audio DSP is interested in knowing
when modem has crashed so that it can perform cleanup and wait for modem to
boot up before it starts processing data again.

Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Siddharth Gupta <sidgup@codeaurora.org>
Link: https://lore.kernel.org/r/1586389003-26675-2-git-send-email-sidgup@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

drivers/remoteproc/qcom_sysmon.c

@@ -46,6 +46,25 @@ struct qcom_sysmon {
 	struct sockaddr_qrtr ssctl;
 };
 
+enum {
+	SSCTL_SSR_EVENT_BEFORE_POWERUP,
+	SSCTL_SSR_EVENT_AFTER_POWERUP,
+	SSCTL_SSR_EVENT_BEFORE_SHUTDOWN,
+	SSCTL_SSR_EVENT_AFTER_SHUTDOWN,
+};
+
+static const char * const sysmon_state_string[] = {
+	[SSCTL_SSR_EVENT_BEFORE_POWERUP]	= "before_powerup",
+	[SSCTL_SSR_EVENT_AFTER_POWERUP]		= "after_powerup",
+	[SSCTL_SSR_EVENT_BEFORE_SHUTDOWN]	= "before_shutdown",
+	[SSCTL_SSR_EVENT_AFTER_SHUTDOWN]	= "after_shutdown",
+};
+
+struct sysmon_event {
+	const char *subsys_name;
+	u32 ssr_event;
+};
+
 static DEFINE_MUTEX(sysmon_lock);
 static LIST_HEAD(sysmon_list);
 
@@ -54,13 +73,15 @@ static LIST_HEAD(sysmon_list);
  * @sysmon:	sysmon context
  * @name:	other remote's name
  */
-static void sysmon_send_event(struct qcom_sysmon *sysmon, const char *name)
+static void sysmon_send_event(struct qcom_sysmon *sysmon,
+			      const struct sysmon_event *event)
 {
 	char req[50];
 	int len;
 	int ret;
 
-	len = snprintf(req, sizeof(req), "ssr:%s:before_shutdown", name);
+	len = snprintf(req, sizeof(req), "ssr:%s:%s", event->subsys_name,
+		       sysmon_state_string[event->ssr_event]);
 	if (len >= sizeof(req))
 		return;
 
@@ -148,13 +169,6 @@ static int sysmon_callback(struct rpmsg_device *rpdev, void *data, int count,
 
 #define SSCTL_SUBSYS_NAME_LENGTH	15
 
-enum {
-	SSCTL_SSR_EVENT_BEFORE_POWERUP,
-	SSCTL_SSR_EVENT_AFTER_POWERUP,
-	SSCTL_SSR_EVENT_BEFORE_SHUTDOWN,
-	SSCTL_SSR_EVENT_AFTER_SHUTDOWN,
-};
-
 enum {
 	SSCTL_SSR_EVENT_FORCED,
 	SSCTL_SSR_EVENT_GRACEFUL,
@@ -331,7 +345,8 @@ static void ssctl_request_shutdown(struct qcom_sysmon *sysmon)
  * @sysmon:	sysmon context
  * @name:	other remote's name
  */
-static void ssctl_send_event(struct qcom_sysmon *sysmon, const char *name)
+static void ssctl_send_event(struct qcom_sysmon *sysmon,
+			     const struct sysmon_event *event)
 {
 	struct ssctl_subsys_event_resp resp;
 	struct ssctl_subsys_event_req req;
@@ -346,9 +361,9 @@ static void ssctl_send_event(struct qcom_sysmon *sysmon, const char *name)
 	}
 
 	memset(&req, 0, sizeof(req));
-	strlcpy(req.subsys_name, name, sizeof(req.subsys_name));
+	strlcpy(req.subsys_name, event->subsys_name, sizeof(req.subsys_name));
 	req.subsys_name_len = strlen(req.subsys_name);
-	req.event = SSCTL_SSR_EVENT_BEFORE_SHUTDOWN;
+	req.event = event->ssr_event;
 	req.evt_driven_valid = true;
 	req.evt_driven = SSCTL_SSR_EVENT_FORCED;
 
@@ -432,8 +447,12 @@ static int sysmon_start(struct rproc_subdev *subdev)
 static void sysmon_stop(struct rproc_subdev *subdev, bool crashed)
 {
 	struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon, subdev);
+	struct sysmon_event event = {
+		.subsys_name = sysmon->name,
+		.ssr_event = SSCTL_SSR_EVENT_BEFORE_SHUTDOWN
+	};
 
-	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)sysmon->name);
+	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)&event);
 
 	/* Don't request graceful shutdown if we've crashed */
 	if (crashed)
@@ -456,19 +475,20 @@ static int sysmon_notify(struct notifier_block *nb, unsigned long event,
 {
 	struct qcom_sysmon *sysmon = container_of(nb, struct qcom_sysmon, nb);
 	struct rproc *rproc = sysmon->rproc;
-	const char *ssr_name = data;
+	struct sysmon_event *sysmon_event = data;
 
 	/* Skip non-running rprocs and the originating instance */
-	if (rproc->state != RPROC_RUNNING || !strcmp(data, sysmon->name)) {
+	if (rproc->state != RPROC_RUNNING ||
+	    !strcmp(sysmon_event->subsys_name, sysmon->name)) {
 		dev_dbg(sysmon->dev, "not notifying %s\n", sysmon->name);
 		return NOTIFY_DONE;
 	}
 
 	/* Only SSCTL version 2 supports SSR events */
 	if (sysmon->ssctl_version == 2)
-		ssctl_send_event(sysmon, ssr_name);
+		ssctl_send_event(sysmon, sysmon_event);
 	else if (sysmon->ept)
-		sysmon_send_event(sysmon, ssr_name);
+		sysmon_send_event(sysmon, sysmon_event);
 
 	return NOTIFY_DONE;
 }