panic: Publish EC_HOST_EVENT_PANIC on panic

Publish EC_HOST_EVENT_PANIC when a panic occurs.

The kernel may use this event to clean up before the system is reset
(e.g. sync the drive).

This will be a no-op if the kernel doesn't handle it.

BUG=b:258195448
BRANCH=None
TEST=Observe event in kernel. Pass panic_event unit test.

Change-Id: I34b9847778bf17dd113e81158bbbdf999ad2ca33
Signed-off-by: Rob Barnes <robbarnes@google.com>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/4063818
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>
Code-Coverage: Zoss <zoss-cl-coverage@prod.google.com>

7 files changed, 85 insertions, 0 deletions

diff --git a/core/cortex-m/panic.c b/core/cortex-m/panic.c
index eefe068931..7d364ec2a0 100644
--- a/core/cortex-m/panic.c
+++ b/core/cortex-m/panic.c
@@ -364,6 +364,9 @@ void __keep report_panic(void)
 	if (IS_ENABLED(CONFIG_ARMV7M_CACHE))
 		cpu_clean_invalidate_dcache();
 
+	if (IS_ENABLED(CONFIG_HOSTCMD_EVENTS))
+		host_set_single_event(EC_HOST_EVENT_PANIC);
+
 	/* Start safe mode if possible */
 	if (IS_ENABLED(CONFIG_SYSTEM_SAFE_MODE)) {
 		/* TODO: check for nested exceptions */
diff --git a/zephyr/shim/src/panic.c b/zephyr/shim/src/panic.c
index e7c13f746d..1a9d7478e4 100644
--- a/zephyr/shim/src/panic.c
+++ b/zephyr/shim/src/panic.c
@@ -4,6 +4,7 @@
  */
 
 #include "common.h"
+#include "host_command.h"
 #include "panic.h"
 #include "system_safe_mode.h"
 
@@ -150,6 +151,9 @@ void k_sys_fatal_error_handler(unsigned int reason, const z_arch_esf_t *esf)
 
 	LOG_PANIC();
 
+	if (IS_ENABLED(CONFIG_HOSTCMD_EVENTS))
+		host_set_single_event(EC_HOST_EVENT_PANIC);
+
 	/* Start system safe mode if possible */
 	if (IS_ENABLED(CONFIG_PLATFORM_EC_SYSTEM_SAFE_MODE)) {
 		if (reason != K_ERR_KERNEL_PANIC &&
diff --git a/zephyr/test/drivers/CMakeLists.txt b/zephyr/test/drivers/CMakeLists.txt
index 8265082543..00328367e3 100644
--- a/zephyr/test/drivers/CMakeLists.txt
+++ b/zephyr/test/drivers/CMakeLists.txt
@@ -25,6 +25,7 @@ add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_I2C_CONTROLLER i2c_controller)
 add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_KEYBOARD_SCAN keyboard_scan)
 add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_LED_DRIVER led_driver)
 add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_MKBP mkbp)
+add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_PANIC_EVENT panic_event)
 add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_PANIC_OUTPUT panic_output)
 add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_POWER_HOST_SLEEP power_host_sleep)
 add_subdirectory_ifdef(CONFIG_LINK_TEST_SUITE_RT9490 rt9490)
diff --git a/zephyr/test/drivers/Kconfig b/zephyr/test/drivers/Kconfig
index 6783661866..14f3d6b513 100644
--- a/zephyr/test/drivers/Kconfig
+++ b/zephyr/test/drivers/Kconfig
@@ -62,6 +62,9 @@ config LINK_TEST_SUITE_LOCATE_CHIP_ALTS
 config LINK_TEST_SUITE_MKBP
 	bool "Link and test the mkbp tests"
 
+config LINK_TEST_SUITE_PANIC_EVENT
+	bool "Link and test the panic_event tests"
+
 config LINK_TEST_SUITE_PANIC_OUTPUT
 	bool "Link and test the panic_output tests"
 
diff --git a/zephyr/test/drivers/panic_event/CMakeLists.txt b/zephyr/test/drivers/panic_event/CMakeLists.txt
new file mode 100644
index 0000000000..25ea751d53
--- /dev/null
+++ b/zephyr/test/drivers/panic_event/CMakeLists.txt
@@ -0,0 +1,6 @@
+# Copyright 2022 The ChromiumOS Authors
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Add source files
+target_sources(app PRIVATE src/panic_event.c)
diff --git a/zephyr/test/drivers/panic_event/src/panic_event.c b/zephyr/test/drivers/panic_event/src/panic_event.c
new file mode 100644
index 0000000000..09796d355f
--- /dev/null
+++ b/zephyr/test/drivers/panic_event/src/panic_event.c
@@ -0,0 +1,65 @@
+/* Copyright 2022 The ChromiumOS Authors
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/**
+ * @file
+ * @brief Unit Tests for panic event.
+ */
+
+#include "common.h"
+#include "ec_tasks.h"
+#include "panic.h"
+#include "system.h"
+#include "test/drivers/stubs.h"
+#include "test/drivers/test_state.h"
+#include "test/drivers/utils.h"
+
+#include <zephyr/device.h>
+#include <zephyr/fff.h>
+#include <zephyr/kernel.h>
+#include <zephyr/logging/log.h>
+#include <zephyr/ztest.h>
+
+struct host_events_ctx events_ctx;
+
+static void before(void *unused)
+{
+	ARG_UNUSED(unused);
+	host_events_save(&events_ctx);
+	host_clear_events(0xffffffff);
+}
+
+static void after(void *unused)
+{
+	ARG_UNUSED(unused);
+	host_events_restore(&events_ctx);
+}
+
+/**
+ * @brief Test Suite: Verifies panic event functionality.
+ */
+ZTEST_SUITE(panic_event, NULL, NULL, before, after, NULL);
+
+/**
+ * @brief TestPurpose: Verify EC_HOST_EVENT_PANIC event is asserted on panic
+ *
+ * Expected Results
+ *  - Success
+ */
+ZTEST_USER(panic_event, test_panic_event_notify)
+{
+#ifdef CONFIG_HOSTCMD_X86
+	/* Enable the EC_HOST_EVENT_PANIC event in the lpc mask */
+	host_event_t lpc_event_mask;
+	host_event_t mask = EC_HOST_EVENT_MASK(EC_HOST_EVENT_PANIC);
+
+	lpc_event_mask = lpc_get_host_event_mask(LPC_HOST_EVENT_SCI);
+	lpc_set_host_event_mask(LPC_HOST_EVENT_SCI, lpc_event_mask | mask);
+#endif
+
+	zassert_false(host_is_event_set(EC_HOST_EVENT_PANIC));
+	k_sys_fatal_error_handler(K_ERR_CPU_EXCEPTION, NULL);
+	zassert_true(host_is_event_set(EC_HOST_EVENT_PANIC));
+}
diff --git a/zephyr/test/drivers/testcase.yaml b/zephyr/test/drivers/testcase.yaml
index dfd18ac110..818a3e4515 100644
--- a/zephyr/test/drivers/testcase.yaml
+++ b/zephyr/test/drivers/testcase.yaml
@@ -150,6 +150,9 @@ tests:
       - CONFIG_LINK_TEST_SUITE_PANIC_OUTPUT=y
       - CONFIG_PLATFORM_EC_CONSOLE_CMD_CRASH=y
       - CONFIG_ZTEST_THREAD_PRIORITY=1
+  drivers.panic_event:
+    extra_configs:
+      - CONFIG_LINK_TEST_SUITE_PANIC_EVENT=y
   drivers.power_host_sleep:
     extra_configs:
       - CONFIG_LINK_TEST_SUITE_POWER_HOST_SLEEP=y