[PATCH 08/11] firmware: arm_scmi: Implement Reset .is_notify_supported callback

[Cristian Marussi]

Add a preliminary check to verify if Reset-related notify enable commands
are supported at all by the running platform, and then provide the callback
needed to allow the core SCMI notification subsytem to fine-grain check if
a specific resource domain supports notifications.

Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
 drivers/firmware/arm_scmi/reset.c | 37 ++++++++++++++++++++++++-------
 1 file changed, 29 insertions(+), 8 deletions(-)

diff --git a/drivers/firmware/arm_scmi/reset.c b/drivers/firmware/arm_scmi/reset.c
index 19970d9f9e36..1b318316535e 100644
--- a/drivers/firmware/arm_scmi/reset.c
+++ b/drivers/firmware/arm_scmi/reset.c
@@ -67,6 +67,7 @@ struct reset_dom_info {
 struct scmi_reset_info {
 	u32 version;
 	int num_domains;
+	bool notify_reset_cmd;
 	struct reset_dom_info *dom_info;
 };
 
@@ -89,18 +90,24 @@ static int scmi_reset_attributes_get(const struct scmi_protocol_handle *ph,
 	}
 
 	ph->xops->xfer_put(ph, t);
+
+	if (!ret)
+		if (!ph->hops->protocol_msg_check(ph, RESET_NOTIFY, NULL))
+			pi->notify_reset_cmd = true;
+
 	return ret;
 }
 
 static int
 scmi_reset_domain_attributes_get(const struct scmi_protocol_handle *ph,
-				 u32 domain, struct reset_dom_info *dom_info,
-				 u32 version)
+				 struct scmi_reset_info *pinfo,
+				 u32 domain, u32 version)
 {
 	int ret;
 	u32 attributes;
 	struct scmi_xfer *t;
 	struct scmi_msg_resp_reset_domain_attributes *attr;
+	struct reset_dom_info *dom_info = pinfo->dom_info + domain;
 
 	ret = ph->xops->xfer_get_init(ph, RESET_DOMAIN_ATTRIBUTES,
 				      sizeof(domain), sizeof(*attr), &t);
@@ -115,7 +122,9 @@ scmi_reset_domain_attributes_get(const struct scmi_protocol_handle *ph,
 		attributes = le32_to_cpu(attr->attributes);
 
 		dom_info->async_reset = SUPPORTS_ASYNC_RESET(attributes);
-		dom_info->reset_notify = SUPPORTS_NOTIFY_RESET(attributes);
+		if (pinfo->notify_reset_cmd)
+			dom_info->reset_notify =
+				SUPPORTS_NOTIFY_RESET(attributes);
 		dom_info->latency_us = le32_to_cpu(attr->latency);
 		if (dom_info->latency_us == U32_MAX)
 			dom_info->latency_us = 0;
@@ -226,6 +235,20 @@ static const struct scmi_reset_proto_ops reset_proto_ops = {
 	.deassert = scmi_reset_domain_deassert,
 };
 
+static bool scmi_reset_notify_supported(const struct scmi_protocol_handle *ph,
+					u8 evt_id, u32 src_id)
+{
+	struct reset_dom_info *dom;
+	struct scmi_reset_info *pi = ph->get_priv(ph);
+
+	if (evt_id != SCMI_EVENT_RESET_ISSUED || src_id >= pi->num_domains)
+		return false;
+
+	dom = pi->dom_info + src_id;
+
+	return dom->reset_notify;
+}
+
 static int scmi_reset_notify(const struct scmi_protocol_handle *ph,
 			     u32 domain_id, bool enable)
 {
@@ -301,6 +324,7 @@ static const struct scmi_event reset_events[] = {
 };
 
 static const struct scmi_event_ops reset_event_ops = {
+	.is_notify_supported = scmi_reset_notify_supported,
 	.get_num_sources = scmi_reset_get_num_sources,
 	.set_notify_enabled = scmi_reset_set_notify_enabled,
 	.fill_custom_report = scmi_reset_fill_custom_report,
@@ -339,11 +363,8 @@ static int scmi_reset_protocol_init(const struct scmi_protocol_handle *ph)
 	if (!pinfo->dom_info)
 		return -ENOMEM;
 
-	for (domain = 0; domain < pinfo->num_domains; domain++) {
-		struct reset_dom_info *dom = pinfo->dom_info + domain;
-
-		scmi_reset_domain_attributes_get(ph, domain, dom, version);
-	}
+	for (domain = 0; domain < pinfo->num_domains; domain++)
+		scmi_reset_domain_attributes_get(ph, pinfo, domain, version);
 
 	pinfo->version = version;
 	return ph->set_priv(ph, pinfo, version);
-- 
2.43.0