[RFC PATCH 08/11] firmware: arm_scmi: Add Perf notifications support

[Cristian Marussi <cristian.marussi@arm.com>]

Make SCMI Perf protocol register with the notification core.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
 drivers/firmware/arm_scmi/perf.c | 162 ++++++++++++++++++++++++++++++-
 include/linux/scmi_protocol.h    |  20 ++++
 2 files changed, 181 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/perf.c b/drivers/firmware/arm_scmi/perf.c
index 88509ec637d0..3e09ced2adc8 100644
--- a/drivers/firmware/arm_scmi/perf.c
+++ b/drivers/firmware/arm_scmi/perf.c
@@ -14,6 +14,7 @@
 #include <linux/sort.h>
 
 #include "common.h"
+#include "notify.h"
 
 enum scmi_performance_protocol_cmd {
 	PERF_DOMAIN_ATTRIBUTES = 0x3,
@@ -86,6 +87,19 @@ struct scmi_perf_notify_level_or_limits {
 	__le32 notify_enable;
 };
 
+struct scmi_perf_limits_notify_payld {
+	__le32 agent_id;
+	__le32 domain_id;
+	__le32 range_max;
+	__le32 range_min;
+};
+
+struct scmi_perf_level_notify_payld {
+	__le32 agent_id;
+	__le32 domain_id;
+	__le32 performance_level;
+};
+
 struct scmi_msg_resp_perf_describe_levels {
 	__le16 num_returned;
 	__le16 num_remaining;
@@ -156,6 +170,14 @@ struct scmi_perf_info {
 	u64 stats_addr;
 	u32 stats_size;
 	struct perf_dom_info *dom_info;
+	const struct scmi_handle *handle;
+};
+
+static struct scmi_perf_info *pinfo;
+
+static enum scmi_performance_protocol_cmd evt_2_cmd[] = {
+	PERF_NOTIFY_LIMITS,
+	PERF_NOTIFY_LEVEL,
 };
 
 static int scmi_perf_attributes_get(const struct scmi_handle *handle,
@@ -488,6 +510,29 @@ static int scmi_perf_level_get(const struct scmi_handle *handle, u32 domain,
 	return scmi_perf_mb_level_get(handle, domain, level, poll);
 }
 
+static int scmi_perf_level_limits_notify(const struct scmi_handle *handle,
+					 u32 domain, int message_id,
+					 bool enable)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_perf_notify_level_or_limits *notify;
+
+	ret = scmi_xfer_get_init(handle, message_id, SCMI_PROTOCOL_PERF,
+				 sizeof(*notify), 0, &t);
+	if (ret)
+		return ret;
+
+	notify = t->tx.buf;
+	notify->domain = cpu_to_le32(domain);
+	notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
+
+	ret = scmi_do_xfer(handle, t);
+
+	scmi_xfer_put(handle, t);
+	return ret;
+}
+
 static bool scmi_perf_fc_size_is_valid(u32 msg, u32 size)
 {
 	if ((msg == PERF_LEVEL_GET || msg == PERF_LEVEL_SET) && size == 4)
@@ -710,11 +755,107 @@ static struct scmi_perf_ops perf_ops = {
 	.est_power_get = scmi_dvfs_est_power_get,
 };
 
+static bool scmi_perf_set_notify_enabled(u8 evt_id, const u32 *src_id,
+					 bool enable)
+{
+	int ret, cmd_id;
+
+	cmd_id = MAP_EVT_TO_ENABLE_CMD(evt_id, evt_2_cmd);
+	if (cmd_id < 0)
+		return false;
+
+	if (src_id) {
+		ret = scmi_perf_level_limits_notify(pinfo->handle,
+						    *src_id, cmd_id, enable);
+		if (ret)
+			pr_warn("Failed enabling SCMI Notifications - Perf - evt[%X] dom[%d] - ret:%d\n",
+				evt_id, *src_id, ret);
+	} else {
+		int r, dom;
+
+		ret = 1;
+		for (dom = 0; dom < pinfo->num_domains; dom++) {
+			r = scmi_perf_level_limits_notify(pinfo->handle, dom,
+							  cmd_id, enable);
+			if (r)
+				pr_warn("Failed enabling SCMI Notifications - Perf - evt[%X] dom[%d] - ret:%d\n",
+					evt_id, dom, r);
+			ret *= r;
+		}
+	}
+
+	return !ret ? true : false;
+}
+
+static void *scmi_perf_fill_custom_report(u8 evt_id, u64 timestamp,
+					  const void *payld, size_t payld_sz,
+					  void *report, u32 *src_id)
+{
+	void *rep = NULL;
+
+	switch (evt_id) {
+	case PERFORMANCE_LIMITS_CHANGED:
+	{
+		const struct scmi_perf_limits_notify_payld *p = payld;
+		struct scmi_perf_limits_report *r = report;
+
+		if (sizeof(*p) != payld_sz)
+			break;
+
+		r->timestamp = timestamp;
+		r->agent_id = le32_to_cpu(p->agent_id);
+		r->domain_id = le32_to_cpu(p->domain_id);
+		r->range_max = le32_to_cpu(p->range_max);
+		r->range_min = le32_to_cpu(p->range_min);
+		*src_id = r->domain_id;
+		rep = r;
+		break;
+	}
+	case PERFORMANCE_LEVEL_CHANGED:
+	{
+		const struct scmi_perf_level_notify_payld *p = payld;
+		struct scmi_perf_level_report *r = report;
+
+		if (sizeof(*p) != payld_sz)
+			break;
+
+		r->timestamp = timestamp;
+		r->agent_id = le32_to_cpu(p->agent_id);
+		r->domain_id = le32_to_cpu(p->domain_id);
+		r->performance_level = le32_to_cpu(p->performance_level);
+		*src_id = r->domain_id;
+		rep = r;
+		break;
+	}
+	default:
+		break;
+	}
+
+	return rep;
+}
+
+static const struct scmi_event perf_events[] = {
+	{
+		.evt_id = PERFORMANCE_LIMITS_CHANGED,
+		.max_payld_sz = 16,
+		.max_report_sz = sizeof(struct scmi_perf_limits_report),
+	},
+	{
+		.evt_id = PERFORMANCE_LEVEL_CHANGED,
+		.max_payld_sz = 12,
+		.max_report_sz = sizeof(struct scmi_perf_level_report),
+	},
+};
+
+static const struct scmi_protocol_event_ops perf_event_ops = {
+	.set_notify_enabled = scmi_perf_set_notify_enabled,
+	.fill_custom_report = scmi_perf_fill_custom_report,
+};
+
 static int scmi_perf_protocol_init(struct scmi_handle *handle)
 {
 	int domain;
 	u32 version;
-	struct scmi_perf_info *pinfo;
 
 	scmi_version_get(handle, SCMI_PROTOCOL_PERF, &version);
 
@@ -742,7 +883,12 @@ static int scmi_perf_protocol_init(struct scmi_handle *handle)
 			scmi_perf_domain_init_fc(handle, domain, &dom->fc_info);
 	}
 
+	scmi_register_protocol_events(SCMI_PROTOCOL_PERF, PAGE_SIZE,
+				      &perf_event_ops, perf_events,
+				      ARRAY_SIZE(perf_events));
+
 	pinfo->version = version;
+	pinfo->handle = handle;
 	handle->perf_ops = &perf_ops;
 	handle->perf_priv = pinfo;
 
@@ -755,3 +901,17 @@ static int __init scmi_perf_init(void)
 				      &scmi_perf_protocol_init);
 }
 subsys_initcall(scmi_perf_init);
+
+int scmi_register_perf_event_notifier(u8 evt_id, u32 *dom_id,
+				      struct notifier_block *nb)
+{
+	return scmi_register_event_notifier(SCMI_PROTOCOL_PERF, evt_id,
+					    dom_id, nb);
+}
+
+int scmi_unregister_perf_event_notifier(u8 evt_id, u32 *dom_id,
+					struct notifier_block *nb)
+{
+	return scmi_unregister_event_notifier(SCMI_PROTOCOL_PERF, evt_id,
+					      dom_id, nb);
+}
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 61bdfe0bebe2..a719f3cd394b 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -344,4 +344,24 @@ int scmi_register_power_event_notifier(u8 evt_id, u32 *dom_id,
 int scmi_unregister_power_event_notifier(u8 evt_id, u32 *dom_id,
 					 struct notifier_block *nb);
 
+struct scmi_perf_limits_report {
+	ktime_t	timestamp;
+	u32	agent_id;
+	u32	domain_id;
+	u32	range_max;
+	u32	range_min;
+};
+
+struct scmi_perf_level_report {
+	ktime_t	timestamp;
+	u32	agent_id;
+	u32	domain_id;
+	u32	performance_level;
+};
+
+int scmi_register_perf_event_notifier(u8 evt_id, u32 *dom_id,
+				      struct notifier_block *nb);
+int scmi_unregister_perf_event_notifier(u8 evt_id, u32 *dom_id,
+					struct notifier_block *nb);
+
 #endif /* _LINUX_SCMI_PROTOCOL_H */
-- 
2.17.1