blob: d12e51da0a21e89e7687119f050867f52975f654 [file] [log] [blame]
Heinrich Schuchardt18081d42017-10-18 18:13:04 +02001/*
2 * EFI watchdog
3 *
4 * Copyright (c) 2017 Heinrich Schuchardt
5 *
6 * SPDX-License-Identifier: GPL-2.0+
7 */
8
9#include <common.h>
10#include <efi_loader.h>
11
12/* Conversion factor from seconds to multiples of 100ns */
13#define EFI_SECONDS_TO_100NS 10000000ULL
14
15static struct efi_event *watchdog_timer_event;
16
17/*
18 * Reset the system when the watchdog event is notified.
19 *
20 * @event: the watchdog event
21 * @context: not used
22 */
23static void EFIAPI efi_watchdog_timer_notify(struct efi_event *event,
24 void *context)
25{
26 EFI_ENTRY("%p, %p", event, context);
27
28 printf("\nEFI: Watchdog timeout\n");
29 EFI_CALL_VOID(efi_runtime_services.reset_system(EFI_RESET_COLD,
30 EFI_SUCCESS, 0, NULL));
31
32 EFI_EXIT(EFI_UNSUPPORTED);
33}
34
35/*
36 * Reset the watchdog timer.
37 *
38 * This function is used by the SetWatchdogTimer service.
39 *
40 * @timeout: seconds before reset by watchdog
41 * @return: status code
42 */
43efi_status_t efi_set_watchdog(unsigned long timeout)
44{
45 efi_status_t r;
46
47 if (timeout)
48 /* Reset watchdog */
49 r = efi_set_timer(watchdog_timer_event, EFI_TIMER_RELATIVE,
50 EFI_SECONDS_TO_100NS * timeout);
51 else
52 /* Deactivate watchdog */
53 r = efi_set_timer(watchdog_timer_event, EFI_TIMER_STOP, 0);
54 return r;
55}
56
57/*
58 * Initialize the EFI watchdog.
59 *
60 * This function is called by efi_init_obj_list()
61 */
Heinrich Schuchardtf2704cc2018-03-03 15:28:57 +010062efi_status_t efi_watchdog_register(void)
Heinrich Schuchardt18081d42017-10-18 18:13:04 +020063{
64 efi_status_t r;
65
66 /*
67 * Create a timer event.
68 */
69 r = efi_create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
Heinrich Schuchardtbf7f1692018-02-18 15:17:52 +010070 efi_watchdog_timer_notify, NULL, NULL,
Heinrich Schuchardt18081d42017-10-18 18:13:04 +020071 &watchdog_timer_event);
72 if (r != EFI_SUCCESS) {
73 printf("ERROR: Failed to register watchdog event\n");
74 return r;
75 }
76 /*
77 * The UEFI standard requires that the watchdog timer is set to five
78 * minutes when invoking an EFI boot option.
79 *
80 * Unified Extensible Firmware Interface (UEFI), version 2.7 Errata A
81 * 7.5. Miscellaneous Boot Services - EFI_BOOT_SERVICES.SetWatchdogTimer
82 */
83 r = efi_set_watchdog(300);
84 if (r != EFI_SUCCESS) {
85 printf("ERROR: Failed to set watchdog timer\n");
86 return r;
87 }
Heinrich Schuchardtf2704cc2018-03-03 15:28:57 +010088 return EFI_SUCCESS;
Heinrich Schuchardt18081d42017-10-18 18:13:04 +020089}