[RFC PATCH v3 13/13] firmware: arm_scmi: Add Base notifications support

From: Cristian Marussi
Date: Mon Feb 24 2020 - 09:42:29 EST


Make SCMI Base protocol register with the notification core.

Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
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/base.c | 109 +++++++++++++++++++++++++++++++
include/linux/scmi_protocol.h | 8 +++
2 files changed, 117 insertions(+)

diff --git a/drivers/firmware/arm_scmi/base.c b/drivers/firmware/arm_scmi/base.c
index ce7d9203e41b..0d4bbf313a4a 100644
--- a/drivers/firmware/arm_scmi/base.c
+++ b/drivers/firmware/arm_scmi/base.c
@@ -6,6 +6,9 @@
*/

#include "common.h"
+#include "notify.h"
+
+#define SCMI_BASE_NUM_SOURCES 1

enum scmi_base_protocol_cmd {
BASE_DISCOVER_VENDOR = 0x3,
@@ -29,6 +32,19 @@ struct scmi_msg_resp_base_attributes {
__le16 reserved;
};

+struct scmi_msg_base_error_notify {
+ __le32 event_control;
+#define BASE_TP_NOTIFY_ALL BIT(0)
+};
+
+struct scmi_base_error_notify_payld {
+ __le32 agent_id;
+ __le32 error_status;
+#define IS_FATAL_ERROR(x) ((x) & BIT(31))
+#define ERROR_CMD_COUNT(x) FIELD_GET(GENMASK(9, 0), (x))
+ __le64 msg_reports[8192];
+};
+
/**
* scmi_base_attributes_get() - gets the implementation details
* that are associated with the base protocol.
@@ -222,6 +238,93 @@ static int scmi_base_discover_agent_get(const struct scmi_handle *handle,
return ret;
}

+static int scmi_base_error_notify(const struct scmi_handle *handle, bool enable)
+{
+ int ret;
+ u32 evt_cntl = enable ? BASE_TP_NOTIFY_ALL : 0;
+ struct scmi_xfer *t;
+ struct scmi_msg_base_error_notify *cfg;
+
+ ret = scmi_xfer_get_init(handle, BASE_NOTIFY_ERRORS,
+ SCMI_PROTOCOL_BASE, sizeof(*cfg), 0, &t);
+ if (ret)
+ return ret;
+
+ cfg = t->tx.buf;
+ cfg->event_control = cpu_to_le32(evt_cntl);
+
+ ret = scmi_do_xfer(handle, t);
+
+ scmi_xfer_put(handle, t);
+ return ret;
+}
+
+static bool scmi_base_set_notify_enabled(const struct scmi_handle *handle,
+ u8 evt_id, u32 src_id, bool enable)
+{
+ int ret;
+
+ ret = scmi_base_error_notify(handle, enable);
+ if (ret)
+ pr_warn("SCMI Notifications - Proto:%X - FAIL_ENABLED - evt[%X] ret:%d\n",
+ SCMI_PROTOCOL_BASE, evt_id, ret);
+
+ return !ret ? true : false;
+}
+
+static void *scmi_base_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 BASE_ERROR_EVENT:
+ {
+ int i;
+ const struct scmi_base_error_notify_payld *p = payld;
+ struct scmi_base_error_report *r = report;
+
+ /*
+ * BaseError notification payload is variable in size but
+ * up to a maximum length determined by the struct ponted by p.
+ * Instead payld_sz is the effective length of this notification
+ * payload so cannot be greater of the maximum allowed size as
+ * pointed by p.
+ */
+ if (sizeof(*p) < payld_sz)
+ break;
+
+ r->timestamp = timestamp;
+ r->agent_id = le32_to_cpu(p->agent_id);
+ r->fatal = IS_FATAL_ERROR(le32_to_cpu(p->error_status));
+ r->cmd_count = ERROR_CMD_COUNT(le32_to_cpu(p->error_status));
+ for (i = 0; i < r->cmd_count; i++)
+ r->reports[i] = le64_to_cpu(p->msg_reports[i]);
+ *src_id = 0;
+ rep = r;
+ break;
+ }
+ default:
+ break;
+ }
+
+ return rep;
+}
+
+static const struct scmi_event base_events[] = {
+ {
+ .evt_id = BASE_ERROR_EVENT,
+ .max_payld_sz = 8192,
+ .max_report_sz = sizeof(struct scmi_base_error_report),
+ },
+};
+
+static const struct scmi_protocol_event_ops base_event_ops = {
+ .set_notify_enabled = scmi_base_set_notify_enabled,
+ .fill_custom_report = scmi_base_fill_custom_report,
+};
+
int scmi_base_protocol_init(struct scmi_handle *h)
{
int id, ret;
@@ -256,6 +359,12 @@ int scmi_base_protocol_init(struct scmi_handle *h)
dev_dbg(dev, "Found %d protocol(s) %d agent(s)\n", rev->num_protocols,
rev->num_agents);

+ scmi_register_protocol_events(handle,
+ SCMI_PROTOCOL_BASE, (4 * PAGE_SIZE),
+ &base_event_ops, base_events,
+ ARRAY_SIZE(base_events),
+ SCMI_BASE_NUM_SOURCES);
+
for (id = 0; id < rev->num_agents; id++) {
scmi_base_discover_agent_get(handle, id, name);
dev_dbg(dev, "Agent %d: %s\n", id, name);
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 91c5fdf567d5..3a1bc8014f51 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -420,4 +420,12 @@ struct scmi_reset_issued_report {
u32 reset_state;
};

+struct scmi_base_error_report {
+ ktime_t timestamp;
+ u32 agent_id;
+ bool fatal;
+ u16 cmd_count;
+ u64 reports[8192];
+};
+
#endif /* _LINUX_SCMI_PROTOCOL_H */
--
2.17.1