[Skiboot] [PATCH V6 01/15] core/pldm: Handle Watchdog timer.
Christophe Lombard
clombard at linux.ibm.com
Tue Aug 29 19:23:55 AEST 2023
Encode a PLDM platform event message to send the heartbeat to the BMC.
Watchdog is "armed" when a
PLDM_EVENT_MESSAGE_GLOBAL_ENABLE_ASYNC_KEEP_ALIVE is received.
Signed-off-by: Christophe Lombard <clombard at linux.ibm.com>
---
core/pldm/Makefile.inc | 1 +
core/pldm/pldm-watchdog.c | 142 ++++++++++++++++++++++++++++++++++++++
include/pldm.h | 5 ++
3 files changed, 148 insertions(+)
create mode 100644 core/pldm/pldm-watchdog.c
diff --git a/core/pldm/Makefile.inc b/core/pldm/Makefile.inc
index 87952dbfe..e3efcc2b1 100644
--- a/core/pldm/Makefile.inc
+++ b/core/pldm/Makefile.inc
@@ -11,6 +11,7 @@ PLDM_OBJS = pldm-mctp.o pldm-responder.o pldm-requester.o
PLDM_OBJS += pldm-base-requests.o pldm-platform-requests.o
PLDM_OBJS += pldm-bios-requests.o pldm-fru-requests.o
PLDM_OBJS += pldm-file-io-requests.o pldm-lid-files.o
+PLDM_OBJS += pldm-watchdog.o
PLDM = $(PLDM_DIR)/built-in.a
$(PLDM): $(PLDM_OBJS:%=$(PLDM_DIR)/%)
diff --git a/core/pldm/pldm-watchdog.c b/core/pldm/pldm-watchdog.c
new file mode 100644
index 000000000..5a36b3dad
--- /dev/null
+++ b/core/pldm/pldm-watchdog.c
@@ -0,0 +1,142 @@
+// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
+// Copyright 2022 IBM Corp.
+
+#define pr_fmt(fmt) "PLDM: " fmt
+
+#include <lock.h>
+#include <stdlib.h>
+#include <string.h>
+#include <opal.h>
+#include <timebase.h>
+#include <timer.h>
+#include <pldm/include/libpldm/platform.h>
+#include "pldm.h"
+
+#define DEFAULT_WATCHDOG_TIMEOUT_SEC (10 * 60) /* 10 min */
+
+/* Whether the watchdog timer is armed and Skiboot should be sending
+ * regular heartbeats.
+ */
+bool watchdog_armed;
+
+/* The period (in seconds) of the PLDM watchdog, as dictated by BMC */
+int watchdog_period_sec = DEFAULT_WATCHDOG_TIMEOUT_SEC;
+
+static uint8_t sequence_number;
+struct timer watchdog_timer;
+
+static void watchdog_reset_timer_complete(struct pldm_rx_data *rx,
+ void *data __unused)
+{
+ struct pldm_platform_event_message_resp response;
+ size_t payload_len;
+ int rc;
+
+ if (rx == NULL) {
+ prlog(PR_ERR, "%s: Response not received\n", __func__);
+ return;
+ }
+
+ /* Decode the message */
+ payload_len = rx->msg_len - sizeof(struct pldm_msg_hdr);
+
+ rc = decode_platform_event_message_resp(
+ rx->msg,
+ payload_len,
+ &response.completion_code,
+ &response.platform_event_status);
+ if (rc != PLDM_SUCCESS || response.completion_code != PLDM_SUCCESS) {
+ prlog(PR_ERR, "Decode PlatformEventMessage Error, rc: %d, cc: %d, pes: %d\n",
+ rc, response.completion_code,
+ response.platform_event_status);
+ }
+}
+
+static int pldm_watchdog_reset_timer(void)
+{
+ uint8_t heartbeat_elapsed_data[2];
+ struct pldm_tx_data *tx;
+ size_t payload_len;
+ size_t data_size;
+ int rc;
+
+ struct pldm_platform_event_message_req event_message_req = {
+ .format_version = PLDM_PLATFORM_EVENT_MESSAGE_FORMAT_VERSION,
+ .tid = HOST_TID,
+ .event_class = PLDM_HEARTBEAT_TIMER_ELAPSED_EVENT,
+ };
+
+ prlog(PR_TRACE, "%s - send the heartbeat to the BMC, sequence: %d, period: %d\n",
+ __func__, sequence_number, watchdog_period_sec);
+
+ /* Send the event request */
+ heartbeat_elapsed_data[0] = PLDM_PLATFORM_EVENT_MESSAGE_FORMAT_VERSION;
+
+ /* We need to make sure that we send the BMC the correct
+ * sequence number. To prevent possible race conditions for the
+ * sequence number, lock it while we're incrementing and
+ * sending it down.
+ */
+ heartbeat_elapsed_data[1] = sequence_number++;
+
+ payload_len = PLDM_PLATFORM_EVENT_MESSAGE_MIN_REQ_BYTES + sizeof(heartbeat_elapsed_data);
+
+ data_size = sizeof(struct pldm_msg_hdr) +
+ sizeof(struct pldm_platform_event_message_req) +
+ sizeof(heartbeat_elapsed_data);
+ tx = zalloc(sizeof(struct pldm_tx_data) + data_size);
+ if (!tx)
+ return OPAL_NO_MEM;
+ tx->data_size = data_size - 1;
+
+ /* Encode the platform event message request */
+ rc = encode_platform_event_message_req(
+ DEFAULT_INSTANCE_ID,
+ event_message_req.format_version,
+ event_message_req.tid,
+ event_message_req.event_class,
+ heartbeat_elapsed_data,
+ sizeof(heartbeat_elapsed_data),
+ (struct pldm_msg *)tx->data,
+ payload_len);
+ if (rc != PLDM_SUCCESS) {
+ prlog(PR_ERR, "Encode PlatformEventMessage Error, rc: %d\n", rc);
+ free(tx);
+ return OPAL_PARAMETER;
+ }
+
+ /* Send and get the response message bytes */
+ rc = pldm_requester_queue(tx, watchdog_reset_timer_complete, NULL);
+ if (rc) {
+ prlog(PR_ERR, "Communication Error, req: PlatformEventMessage, rc: %d\n", rc);
+ free(tx);
+ return rc;
+ }
+
+ free(tx);
+ return OPAL_SUCCESS;
+}
+
+static void watchdog_poller(struct timer *t __unused,
+ void *data __unused,
+ uint64_t now __unused)
+{
+ /* Whether the watchdog timer is armed and Skiboot should be sending
+ * regular heartbeats.
+ */
+ if (watchdog_armed)
+ pldm_watchdog_reset_timer();
+
+ schedule_timer(&watchdog_timer, secs_to_tb(watchdog_period_sec));
+}
+
+int pldm_watchdog_init(void)
+{
+ if (watchdog_armed)
+ pldm_watchdog_reset_timer();
+
+ init_timer(&watchdog_timer, watchdog_poller, NULL);
+ schedule_timer(&watchdog_timer, secs_to_tb(watchdog_period_sec));
+
+ return OPAL_SUCCESS;
+}
diff --git a/include/pldm.h b/include/pldm.h
index 8622453be..80ee85c00 100644
--- a/include/pldm.h
+++ b/include/pldm.h
@@ -48,4 +48,9 @@ int pldm_lid_files_init(struct blocklevel_device **bl);
*/
bool pldm_lid_files_exit(struct blocklevel_device *bl);
+/**
+ * Initialize and reset the watchdog
+ */
+int pldm_watchdog_init(void);
+
#endif /* __PLDM_H__ */
--
2.41.0
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