1 files changed, 89 insertions, 0 deletions
diff --git a/lib/efi_loader/efi_watchdog.c b/lib/efi_loader/efi_watchdog.c
new file mode 100644
index 0000000000..35a45dedf8
--- /dev/null
+++ b/lib/efi_loader/efi_watchdog.c
@@ -0,0 +1,89 @@
+/*
+ *  EFI watchdog
+ *
+ *  Copyright (c) 2017 Heinrich Schuchardt
+ *
+ *  SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <efi_loader.h>
+
+/* Conversion factor from seconds to multiples of 100ns */
+#define EFI_SECONDS_TO_100NS 10000000ULL
+
+static struct efi_event *watchdog_timer_event;
+
+/*
+ * Reset the system when the watchdog event is notified.
+ *
+ * @event:	the watchdog event
+ * @context:	not used
+ */
+static void EFIAPI efi_watchdog_timer_notify(struct efi_event *event,
+					     void *context)
+{
+	EFI_ENTRY("%p, %p", event, context);
+
+	printf("\nEFI: Watchdog timeout\n");
+	EFI_CALL_VOID(efi_runtime_services.reset_system(EFI_RESET_COLD,
+							EFI_SUCCESS, 0, NULL));
+
+	EFI_EXIT(EFI_UNSUPPORTED);
+}
+
+/*
+ * Reset the watchdog timer.
+ *
+ * This function is used by the SetWatchdogTimer service.
+ *
+ * @timeout:		seconds before reset by watchdog
+ * @return:		status code
+ */
+efi_status_t efi_set_watchdog(unsigned long timeout)
+{
+	efi_status_t r;
+
+	if (timeout)
+		/* Reset watchdog */
+		r = efi_set_timer(watchdog_timer_event, EFI_TIMER_RELATIVE,
+				  EFI_SECONDS_TO_100NS * timeout);
+	else
+		/* Deactivate watchdog */
+		r = efi_set_timer(watchdog_timer_event, EFI_TIMER_STOP, 0);
+	return r;
+}
+
+/*
+ * Initialize the EFI watchdog.
+ *
+ * This function is called by efi_init_obj_list()
+ */
+int efi_watchdog_register(void)
+{
+	efi_status_t r;
+
+	/*
+	 * Create a timer event.
+	 */
+	r = efi_create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
+			     efi_watchdog_timer_notify, NULL,
+			     &watchdog_timer_event);
+	if (r != EFI_SUCCESS) {
+		printf("ERROR: Failed to register watchdog event\n");
+		return r;
+	}
+	/*
+	 * The UEFI standard requires that the watchdog timer is set to five
+	 * minutes when invoking an EFI boot option.
+	 *
+	 * Unified Extensible Firmware Interface (UEFI), version 2.7 Errata A
+	 * 7.5. Miscellaneous Boot Services - EFI_BOOT_SERVICES.SetWatchdogTimer
+	 */
+	r = efi_set_watchdog(300);
+	if (r != EFI_SUCCESS) {
+		printf("ERROR: Failed to set watchdog timer\n");
+		return r;
+	}
+	return 0;
+}