idc: check if secondary core is down before sending IDC

If for any reason a secondary core is down, IDC message has no
chance to be processed. This may lead to process hang in case
of blocking calls and to undefined actions in case of non
blocking.

This commit adds a check and error log message in case of
target core is down.

Signed-off-by: Marcin Szkudlinski <marcin.szkudlinski@intel.com>

Author: marcinszkudlinski

src/idc/zephyr_idc.c

@@ -30,6 +30,16 @@
 #include <rtos/alloc.h>
 #include <rtos/spinlock.h>
 #include <ipc/topology.h>
+#include <sof/trace/trace.h>
+#include <sof/lib/uuid.h>
+
+LOG_MODULE_REGISTER(zephyr_idc, CONFIG_SOF_LOG_LEVEL);
+
+/* 5f1ec3f8-faaf-4099-903c-cee98351f169 */
+DECLARE_SOF_UUID("zephyr-idc", zephyr_idc_uuid, 0x5f1ec3f8, 0xfaaf, 0x4099,
+		 0x90, 0x3c, 0xce, 0xe9, 0x83, 0x51, 0xf1, 0x69);
+
+DECLARE_TR_CTX(zephyr_idc_tr, SOF_UUID(zephyr_idc_uuid), LOG_LEVEL_INFO);
 
 /*
  * Inter-CPU communication is only used in
@@ -119,6 +129,10 @@ int idc_send_msg(struct idc_msg *msg, uint32_t mode)
 	work->handler = idc_handler;
 	work->sync = mode == IDC_BLOCKING;
 
+	if (!cpu_is_core_enabled(target_cpu)) {
+		tr_err(&zephyr_idc_tr, "Core %u is down, cannot sent IDC message", target_cpu);
+		return -EACCES;
+	}
 	if (msg->payload) {
 		idc_send_memcpy_err = memcpy_s(payload->data, sizeof(payload->data),
 					       msg->payload, msg->size);