1 files changed, 273 insertions, 45 deletions

diff --git a/drivers/remoteproc/qcom_sysmon.c b/drivers/remoteproc/qcom_sysmon.c
index e976a602b015..660ac6fc4082 100644
--- a/drivers/remoteproc/qcom_sysmon.c
+++ b/drivers/remoteproc/qcom_sysmon.c
@@ -6,9 +6,9 @@
 #include <linux/module.h>
 #include <linux/notifier.h>
 #include <linux/slab.h>
+#include <linux/interrupt.h>
 #include <linux/io.h>
-#include <linux/notifier.h>
-#include <linux/of_platform.h>
+#include <linux/of_irq.h>
 #include <linux/platform_device.h>
 #include <linux/remoteproc/qcom_rproc.h>
 #include <linux/rpmsg.h>
@@ -21,10 +21,14 @@ struct qcom_sysmon {
 	struct rproc_subdev subdev;
 	struct rproc *rproc;
 
+	int state;
+	struct mutex state_lock;
+
 	struct list_head node;
 
 	const char *name;
 
+	int shutdown_irq;
 	int ssctl_version;
 	int ssctl_instance;
 
@@ -34,29 +38,54 @@ struct qcom_sysmon {
 
 	struct rpmsg_endpoint *ept;
 	struct completion comp;
+	struct completion ind_comp;
+	struct completion shutdown_comp;
+	struct completion ssctl_comp;
 	struct mutex lock;
 
 	bool ssr_ack;
+	bool shutdown_acked;
 
 	struct qmi_handle qmi;
 	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);
 
 /**
  * sysmon_send_event() - send notification of other remote's SSR event
  * @sysmon:	sysmon context
- * @name:	other remote's name
+ * @event:	sysmon event context
  */
-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;
 
@@ -87,10 +116,13 @@ out_unlock:
 /**
  * sysmon_request_shutdown() - request graceful shutdown of remote
  * @sysmon:	sysmon context
+ *
+ * Return: boolean indicator of the remote processor acking the request
  */
-static void sysmon_request_shutdown(struct qcom_sysmon *sysmon)
+static bool sysmon_request_shutdown(struct qcom_sysmon *sysmon)
 {
 	char *req = "ssr:shutdown";
+	bool acked = false;
 	int ret;
 
 	mutex_lock(&sysmon->lock);
@@ -113,9 +145,13 @@ static void sysmon_request_shutdown(struct qcom_sysmon *sysmon)
 	if (!sysmon->ssr_ack)
 		dev_err(sysmon->dev,
 			"unexpected response to sysmon shutdown request\n");
+	else
+		acked = true;
 
 out_unlock:
 	mutex_unlock(&sysmon->lock);
+
+	return acked;
 }
 
 static int sysmon_callback(struct rpmsg_device *rpdev, void *data, int count,
@@ -137,6 +173,7 @@ static int sysmon_callback(struct rpmsg_device *rpdev, void *data, int count,
 }
 
 #define SSCTL_SHUTDOWN_REQ		0x21
+#define SSCTL_SHUTDOWN_READY_IND	0x21
 #define SSCTL_SUBSYS_EVENT_REQ		0x23
 
 #define SSCTL_MAX_MSG_LEN		7
@@ -144,13 +181,6 @@ 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,
 };
@@ -159,7 +189,7 @@ struct ssctl_shutdown_resp {
 	struct qmi_response_type_v01 resp;
 };
 
-static struct qmi_elem_info ssctl_shutdown_resp_ei[] = {
+static const struct qmi_elem_info ssctl_shutdown_resp_ei[] = {
 	{
 		.data_type	= QMI_STRUCT,
 		.elem_len	= 1,
@@ -180,7 +210,7 @@ struct ssctl_subsys_event_req {
 	u32 evt_driven;
 };
 
-static struct qmi_elem_info ssctl_subsys_event_req_ei[] = {
+static const struct qmi_elem_info ssctl_subsys_event_req_ei[] = {
 	{
 		.data_type	= QMI_DATA_LEN,
 		.elem_len	= 1,
@@ -238,7 +268,7 @@ struct ssctl_subsys_event_resp {
 	struct qmi_response_type_v01 resp;
 };
 
-static struct qmi_elem_info ssctl_subsys_event_resp_ei[] = {
+static const struct qmi_elem_info ssctl_subsys_event_resp_ei[] = {
 	{
 		.data_type	= QMI_STRUCT,
 		.elem_len	= 1,
@@ -252,20 +282,64 @@ static struct qmi_elem_info ssctl_subsys_event_resp_ei[] = {
 	{}
 };
 
+static const struct qmi_elem_info ssctl_shutdown_ind_ei[] = {
+	{}
+};
+
+static void sysmon_ind_cb(struct qmi_handle *qmi, struct sockaddr_qrtr *sq,
+			  struct qmi_txn *txn, const void *data)
+{
+	struct qcom_sysmon *sysmon = container_of(qmi, struct qcom_sysmon, qmi);
+
+	complete(&sysmon->ind_comp);
+}
+
+static const struct qmi_msg_handler qmi_indication_handler[] = {
+	{
+		.type = QMI_INDICATION,
+		.msg_id = SSCTL_SHUTDOWN_READY_IND,
+		.ei = ssctl_shutdown_ind_ei,
+		.decoded_size = 0,
+		.fn = sysmon_ind_cb
+	},
+	{}
+};
+
+static bool ssctl_request_shutdown_wait(struct qcom_sysmon *sysmon)
+{
+	int ret;
+
+	ret = wait_for_completion_timeout(&sysmon->shutdown_comp, 10 * HZ);
+	if (ret)
+		return true;
+
+	ret = try_wait_for_completion(&sysmon->ind_comp);
+	if (ret)
+		return true;
+
+	dev_err(sysmon->dev, "timeout waiting for shutdown ack\n");
+	return false;
+}
+
 /**
  * ssctl_request_shutdown() - request shutdown via SSCTL QMI service
  * @sysmon:	sysmon context
+ *
+ * Return: boolean indicator of the remote processor acking the request
  */
-static void ssctl_request_shutdown(struct qcom_sysmon *sysmon)
+static bool ssctl_request_shutdown(struct qcom_sysmon *sysmon)
 {
 	struct ssctl_shutdown_resp resp;
 	struct qmi_txn txn;
+	bool acked = false;
 	int ret;
 
+	reinit_completion(&sysmon->ind_comp);
+	reinit_completion(&sysmon->shutdown_comp);
 	ret = qmi_txn_init(&sysmon->qmi, &txn, ssctl_shutdown_resp_ei, &resp);
 	if (ret < 0) {
 		dev_err(sysmon->dev, "failed to allocate QMI txn\n");
-		return;
+		return false;
 	}
 
 	ret = qmi_send_request(&sysmon->qmi, &sysmon->ssctl, &txn,
@@ -273,24 +347,32 @@ static void ssctl_request_shutdown(struct qcom_sysmon *sysmon)
 	if (ret < 0) {
 		dev_err(sysmon->dev, "failed to send shutdown request\n");
 		qmi_txn_cancel(&txn);
-		return;
+		return false;
 	}
 
 	ret = qmi_txn_wait(&txn, 5 * HZ);
-	if (ret < 0)
-		dev_err(sysmon->dev, "failed receiving QMI response\n");
-	else if (resp.resp.result)
-		dev_err(sysmon->dev, "shutdown request failed\n");
-	else
+	if (ret < 0) {
+		dev_err(sysmon->dev, "timeout waiting for shutdown response\n");
+	} else if (resp.resp.result) {
+		dev_err(sysmon->dev, "shutdown request rejected\n");
+	} else {
 		dev_dbg(sysmon->dev, "shutdown request completed\n");
+		acked = true;
+	}
+
+	if (sysmon->shutdown_irq > 0)
+		return ssctl_request_shutdown_wait(sysmon);
+
+	return acked;
 }
 
 /**
  * ssctl_send_event() - send notification of other remote's SSR event
  * @sysmon:	sysmon context
- * @name:	other remote's name
+ * @event:	sysmon event context
  */
-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;
@@ -305,9 +387,9 @@ 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));
+	strscpy(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;
 
@@ -315,18 +397,18 @@ static void ssctl_send_event(struct qcom_sysmon *sysmon, const char *name)
 			       SSCTL_SUBSYS_EVENT_REQ, 40,
 			       ssctl_subsys_event_req_ei, &req);
 	if (ret < 0) {
-		dev_err(sysmon->dev, "failed to send shutdown request\n");
+		dev_err(sysmon->dev, "failed to send subsystem event\n");
 		qmi_txn_cancel(&txn);
 		return;
 	}
 
 	ret = qmi_txn_wait(&txn, 5 * HZ);
 	if (ret < 0)
-		dev_err(sysmon->dev, "failed receiving QMI response\n");
+		dev_err(sysmon->dev, "timeout waiting for subsystem event response\n");
 	else if (resp.resp.result)
-		dev_err(sysmon->dev, "ssr event send failed\n");
+		dev_err(sysmon->dev, "subsystem event rejected\n");
 	else
-		dev_dbg(sysmon->dev, "ssr event send completed\n");
+		dev_dbg(sysmon->dev, "subsystem event accepted\n");
 }
 
 /**
@@ -353,7 +435,7 @@ static int ssctl_new_server(struct qmi_handle *qmi, struct qmi_service *svc)
 		break;
 	default:
 		return -EINVAL;
-	};
+	}
 
 	sysmon->ssctl_version = svc->version;
 
@@ -363,6 +445,8 @@ static int ssctl_new_server(struct qmi_handle *qmi, struct qmi_service *svc)
 
 	svc->priv = sysmon;
 
+	complete(&sysmon->ssctl_comp);
+
 	return 0;
 }
 
@@ -383,25 +467,113 @@ static const struct qmi_ops ssctl_ops = {
 	.del_server = ssctl_del_server,
 };
 
+static int sysmon_prepare(struct rproc_subdev *subdev)
+{
+	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_POWERUP
+	};
+
+	mutex_lock(&sysmon->state_lock);
+	sysmon->state = SSCTL_SSR_EVENT_BEFORE_POWERUP;
+	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)&event);
+	mutex_unlock(&sysmon->state_lock);
+
+	return 0;
+}
+
+/**
+ * sysmon_start() - start callback for the sysmon remoteproc subdevice
+ * @subdev:	instance of the sysmon subdevice
+ *
+ * Inform all the listners of sysmon notifications that the rproc associated
+ * to @subdev has booted up. The rproc that booted up also needs to know
+ * which rprocs are already up and running, so send start notifications
+ * on behalf of all the online rprocs.
+ */
 static int sysmon_start(struct rproc_subdev *subdev)
 {
+	struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon,
+						  subdev);
+	struct qcom_sysmon *target;
+	struct sysmon_event event = {
+		.subsys_name = sysmon->name,
+		.ssr_event = SSCTL_SSR_EVENT_AFTER_POWERUP
+	};
+
+	reinit_completion(&sysmon->ssctl_comp);
+	mutex_lock(&sysmon->state_lock);
+	sysmon->state = SSCTL_SSR_EVENT_AFTER_POWERUP;
+	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)&event);
+	mutex_unlock(&sysmon->state_lock);
+
+	mutex_lock(&sysmon_lock);
+	list_for_each_entry(target, &sysmon_list, node) {
+		mutex_lock(&target->state_lock);
+		if (target == sysmon || target->state != SSCTL_SSR_EVENT_AFTER_POWERUP) {
+			mutex_unlock(&target->state_lock);
+			continue;
+		}
+
+		event.subsys_name = target->name;
+		event.ssr_event = target->state;
+
+		if (sysmon->ssctl_version == 2)
+			ssctl_send_event(sysmon, &event);
+		else if (sysmon->ept)
+			sysmon_send_event(sysmon, &event);
+		mutex_unlock(&target->state_lock);
+	}
+	mutex_unlock(&sysmon_lock);
+
 	return 0;
 }
 
 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
+	};
+
+	sysmon->shutdown_acked = false;
 
-	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)sysmon->name);
+	mutex_lock(&sysmon->state_lock);
+	sysmon->state = SSCTL_SSR_EVENT_BEFORE_SHUTDOWN;
+	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)&event);
+	mutex_unlock(&sysmon->state_lock);
 
 	/* Don't request graceful shutdown if we've crashed */
 	if (crashed)
 		return;
 
+	if (sysmon->ssctl_instance) {
+		if (!wait_for_completion_timeout(&sysmon->ssctl_comp, HZ / 2))
+			dev_err(sysmon->dev, "timeout waiting for ssctl service\n");
+	}
+
 	if (sysmon->ssctl_version)
-		ssctl_request_shutdown(sysmon);
+		sysmon->shutdown_acked = ssctl_request_shutdown(sysmon);
 	else if (sysmon->ept)
-		sysmon_request_shutdown(sysmon);
+		sysmon->shutdown_acked = sysmon_request_shutdown(sysmon);
+}
+
+static void sysmon_unprepare(struct rproc_subdev *subdev)
+{
+	struct qcom_sysmon *sysmon = container_of(subdev, struct qcom_sysmon,
+						  subdev);
+	struct sysmon_event event = {
+		.subsys_name = sysmon->name,
+		.ssr_event = SSCTL_SSR_EVENT_AFTER_SHUTDOWN
+	};
+
+	mutex_lock(&sysmon->state_lock);
+	sysmon->state = SSCTL_SSR_EVENT_AFTER_SHUTDOWN;
+	blocking_notifier_call_chain(&sysmon_notifiers, 0, (void *)&event);
+	mutex_unlock(&sysmon->state_lock);
 }
 
 /**
@@ -414,31 +586,40 @@ static int sysmon_notify(struct notifier_block *nb, unsigned long event,
 			 void *data)
 {
 	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 (sysmon->state != SSCTL_SSR_EVENT_AFTER_POWERUP ||
+	    !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;
 }
 
+static irqreturn_t sysmon_shutdown_interrupt(int irq, void *data)
+{
+	struct qcom_sysmon *sysmon = data;
+
+	complete(&sysmon->shutdown_comp);
+
+	return IRQ_HANDLED;
+}
+
 /**
  * qcom_add_sysmon_subdev() - create a sysmon subdev for the given remoteproc
  * @rproc:	rproc context to associate the subdev with
  * @name:	name of this subdev, to use in SSR
  * @ssctl_instance: instance id of the ssctl QMI service
  *
- * Return: A new qcom_sysmon object, or NULL on failure
+ * Return: A new qcom_sysmon object, or an error pointer on failure
  */
 struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
 					   const char *name,
@@ -449,7 +630,7 @@ struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
 
 	sysmon = kzalloc(sizeof(*sysmon), GFP_KERNEL);
 	if (!sysmon)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	sysmon->dev = rproc->dev.parent;
 	sysmon->rproc = rproc;
@@ -458,19 +639,50 @@ struct qcom_sysmon *qcom_add_sysmon_subdev(struct rproc *rproc,
 	sysmon->ssctl_instance = ssctl_instance;
 
 	init_completion(&sysmon->comp);
+	init_completion(&sysmon->ind_comp);
+	init_completion(&sysmon->shutdown_comp);
+	init_completion(&sysmon->ssctl_comp);
 	mutex_init(&sysmon->lock);
+	mutex_init(&sysmon->state_lock);
+
+	sysmon->shutdown_irq = of_irq_get_byname(sysmon->dev->of_node,
+						 "shutdown-ack");
+	if (sysmon->shutdown_irq < 0) {
+		if (sysmon->shutdown_irq != -ENODATA) {
+			dev_err(sysmon->dev,
+				"failed to retrieve shutdown-ack IRQ\n");
+			ret = sysmon->shutdown_irq;
+			kfree(sysmon);
+			return ERR_PTR(ret);
+		}
+	} else {
+		ret = devm_request_threaded_irq(sysmon->dev,
+						sysmon->shutdown_irq,
+						NULL, sysmon_shutdown_interrupt,
+						IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+						"q6v5 shutdown-ack", sysmon);
+		if (ret) {
+			dev_err(sysmon->dev,
+				"failed to acquire shutdown-ack IRQ\n");
+			kfree(sysmon);
+			return ERR_PTR(ret);
+		}
+	}
 
-	ret = qmi_handle_init(&sysmon->qmi, SSCTL_MAX_MSG_LEN, &ssctl_ops, NULL);
+	ret = qmi_handle_init(&sysmon->qmi, SSCTL_MAX_MSG_LEN, &ssctl_ops,
+			      qmi_indication_handler);
 	if (ret < 0) {
 		dev_err(sysmon->dev, "failed to initialize qmi handle\n");
 		kfree(sysmon);
-		return NULL;
+		return ERR_PTR(ret);
 	}
 
 	qmi_add_lookup(&sysmon->qmi, 43, 0, 0);
 
+	sysmon->subdev.prepare = sysmon_prepare;
 	sysmon->subdev.start = sysmon_start;
 	sysmon->subdev.stop = sysmon_stop;
+	sysmon->subdev.unprepare = sysmon_unprepare;
 
 	rproc_add_subdev(rproc, &sysmon->subdev);
 
@@ -509,6 +721,22 @@ void qcom_remove_sysmon_subdev(struct qcom_sysmon *sysmon)
 EXPORT_SYMBOL_GPL(qcom_remove_sysmon_subdev);
 
 /**
+ * qcom_sysmon_shutdown_acked() - query the success of the last shutdown
+ * @sysmon:	sysmon context
+ *
+ * When sysmon is used to request a graceful shutdown of the remote processor
+ * this can be used by the remoteproc driver to query the success, in order to
+ * know if it should fall back to other means of requesting a shutdown.
+ *
+ * Return: boolean indicator of the success of the last shutdown request
+ */
+bool qcom_sysmon_shutdown_acked(struct qcom_sysmon *sysmon)
+{
+	return sysmon && sysmon->shutdown_acked;
+}
+EXPORT_SYMBOL_GPL(qcom_sysmon_shutdown_acked);
+
+/**
  * sysmon_probe() - probe sys_mon channel
  * @rpdev:	rpmsg device handle
  *