[PATCH v4 09/13] firmware: arm_scmi: Add Power notifications support

Cristian Marussi
2020-03-04T16:26:50Z

Make SCMI Power protocol register with the notification core.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
---
V3 --> V4
- scmi_event field renamed
V2 --> V3
- added handle awareness
V1 --> V2
- simplified .set_notify_enabled() implementation moving the ALL_SRCIDs
logic out of protocol. ALL_SRCIDs logic is now in charge of the
notification core, together with proper reference counting of enables
- switched to devres protocol-registration
---
drivers/firmware/arm_scmi/power.c | 123 ++++++++++++++++++++++++++++++
include/linux/scmi_protocol.h | 15 ++++
2 files changed, 138 insertions(+)

diff --git a/drivers/firmware/arm_scmi/power.c b/drivers/firmware/arm_scmi/power.c
index cf7f0312381b..281da7e7e33a 100644
--- a/drivers/firmware/arm_scmi/power.c
+++ b/drivers/firmware/arm_scmi/power.c
@@ -6,6 +6,7 @@
*/

#include "common.h"
+#include "notify.h"

enum scmi_power_protocol_cmd {
POWER_DOMAIN_ATTRIBUTES = 0x3,
@@ -48,6 +49,12 @@ struct scmi_power_state_notify {
__le32 notify_enable;
};

+struct scmi_power_state_notify_payld {
+ __le32 agent_id;
+ __le32 domain_id;
+ __le32 power_state;
+};
+
struct power_dom_info {
bool state_set_sync;
bool state_set_async;
@@ -63,6 +70,11 @@ struct scmi_power_info {
struct power_dom_info *dom_info;
};

+static enum scmi_power_protocol_cmd evt_2_cmd[] = {
+ POWER_STATE_NOTIFY,
+ POWER_STATE_CHANGE_REQUESTED_NOTIFY,
+};
+
static int scmi_power_attributes_get(const struct scmi_handle *handle,
struct scmi_power_info *pi)
{
@@ -186,6 +198,111 @@ static struct scmi_power_ops power_ops = {
.state_get = scmi_power_state_get,
};

+static int scmi_power_request_notify(const struct scmi_handle *handle,
+ u32 domain, int message_id, bool enable)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct scmi_power_state_notify *notify;
+
+ ret = scmi_xfer_get_init(handle, message_id, SCMI_PROTOCOL_POWER,
+ 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_power_set_notify_enabled(const struct scmi_handle *handle,
+ u8 evt_id, 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;
+
+ ret = scmi_power_request_notify(handle, src_id, cmd_id, enable);
+ if (ret)
+ pr_warn("SCMI Notifications - Proto:%X - FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n",
+ SCMI_PROTOCOL_POWER, evt_id, src_id, ret);
+
+ return !ret ? true : false;
+}
+
+static void *scmi_power_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 POWER_STATE_CHANGED:
+ {
+ const struct scmi_power_state_notify_payld *p = payld;
+ struct scmi_power_state_changed_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->power_state = le32_to_cpu(p->power_state);
+ *src_id = r->domain_id;
+ rep = r;
+ break;
+ }
+ case POWER_STATE_CHANGE_REQUESTED:
+ {
+ const struct scmi_power_state_notify_payld *p = payld;
+ struct scmi_power_state_change_requested_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->power_state = le32_to_cpu(p->power_state);
+ *src_id = r->domain_id;
+ rep = r;
+ break;
+ }
+ default:
+ break;
+ }
+
+ return rep;
+}
+
+static const struct scmi_event power_events[] = {
+ {
+ .id = POWER_STATE_CHANGED,
+ .max_payld_sz = 12,
+ .max_report_sz =
+ sizeof(struct scmi_power_state_changed_report),
+ },
+ {
+ .id = POWER_STATE_CHANGE_REQUESTED,
+ .max_payld_sz = 12,
+ .max_report_sz =
+ sizeof(struct scmi_power_state_change_requested_report),
+ },
+};
+
+static const struct scmi_protocol_event_ops power_event_ops = {
+ .set_notify_enabled = scmi_power_set_notify_enabled,
+ .fill_custom_report = scmi_power_fill_custom_report,
+};
+
static int scmi_power_protocol_init(struct scmi_handle *handle)
{
int domain;
@@ -214,6 +331,12 @@ static int scmi_power_protocol_init(struct scmi_handle *handle)
scmi_power_domain_attributes_get(handle, domain, dom);
}

+ scmi_register_protocol_events(handle,
+ SCMI_PROTOCOL_POWER, PAGE_SIZE,
+ &power_event_ops, power_events,
+ ARRAY_SIZE(power_events),
+ pinfo->num_domains);
+
pinfo->version = version;
handle->power_ops = &power_ops;
handle->power_priv = pinfo;
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 797e1e03ae52..baa117f9eda3 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -377,4 +377,19 @@ typedef int (*scmi_prot_init_fn_t)(struct scmi_handle *);
int scmi_protocol_register(int protocol_id, scmi_prot_init_fn_t fn);
void scmi_protocol_unregister(int protocol_id);

+/* SCMI Notification API - Custom Event Reports */
+struct scmi_power_state_changed_report {
+ ktime_t timestamp;
+ u32 agent_id;
+ u32 domain_id;
+ u32 power_state;
+};
+
+struct scmi_power_state_change_requested_report {
+ ktime_t timestamp;
+ u32 agent_id;
+ u32 domain_id;
+ u32 power_state;
+};
+
#endif /* _LINUX_SCMI_PROTOCOL_H */
--
2.17.1