iPXE
efi_watchdog.c
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1 /*
2  * Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation; either version 2 of the
7  * License, or any later version.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17  * 02110-1301, USA.
18  *
19  * You can also choose to distribute this program under the terms of
20  * the Unmodified Binary Distribution Licence (as given in the file
21  * COPYING.UBDL), provided that you have satisfied its requirements.
22  */
23 
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25 
26 /**
27  * @file
28  *
29  * EFI watchdog holdoff timer
30  *
31  */
32 
33 #include <errno.h>
34 #include <string.h>
35 #include <ipxe/retry.h>
36 #include <ipxe/timer.h>
37 #include <ipxe/init.h>
38 #include <ipxe/efi/efi.h>
39 #include <ipxe/efi/efi_watchdog.h>
40 
41 /** Watchdog holdoff interval (in seconds) */
42 #define WATCHDOG_HOLDOFF_SECS 10
43 
44 /** Watchdog timeout (in seconds) */
45 #define WATCHDOG_TIMEOUT_SECS ( 5 * 60 )
46 
47 /** Watchdog code (to be logged on watchdog timeout) */
48 #define WATCHDOG_CODE 0x6950584544454144ULL
49 
50 /** Watchdog data (to be logged on watchdog timeout) */
51 #define WATCHDOG_DATA L"iPXE";
52 
53 /**
54  * Hold off watchdog timer
55  *
56  * @v retry Retry timer
57  * @v over Failure indicator
58  */
59 static void efi_watchdog_expired ( struct retry_timer *timer,
60  int over __unused ) {
62  static CHAR16 data[] = WATCHDOG_DATA;
63  EFI_STATUS efirc;
64  int rc;
65 
66  DBGC2 ( timer, "EFI holding off watchdog timer\n" );
67 
68  /* Restart this holdoff timer */
70 
71  /* Reset watchdog timer */
72  if ( ( efirc = bs->SetWatchdogTimer ( WATCHDOG_TIMEOUT_SECS,
73  WATCHDOG_CODE, sizeof ( data ),
74  data ) ) != 0 ) {
75  rc = -EEFI ( efirc );
76  DBGC ( timer, "EFI could not set watchdog timer: %s\n",
77  strerror ( rc ) );
78  return;
79  }
80 }
81 
82 /** Watchdog holdoff timer */
84 
85 /**
86  * Disable watching when shutting down to boot an operating system
87  *
88  * @v booting System is shutting down for OS boot
89  */
90 static void efi_watchdog_shutdown ( int booting ) {
92  EFI_STATUS efirc;
93  int rc;
94 
95  /* If we are shutting down to boot an operating system, then
96  * disable the boot services watchdog timer. The UEFI
97  * specification mandates that the platform firmware does this
98  * as part of the ExitBootServices() call, but some platforms
99  * (e.g. Hyper-V) are observed to occasionally forget to do
100  * so, resulting in a reboot approximately five minutes after
101  * starting the operating system.
102  */
103  if ( booting &&
104  ( ( efirc = bs->SetWatchdogTimer ( 0, 0, 0, NULL ) ) != 0 ) ) {
105  rc = -EEFI ( efirc );
106  DBGC ( &efi_watchdog, "EFI could not disable watchdog timer: "
107  "%s\n", strerror ( rc ) );
108  /* Nothing we can do */
109  }
110 }
111 
112 /** Watchdog startup/shutdown function */
113 struct startup_fn efi_watchdog_startup_fn __startup_fn ( STARTUP_EARLY ) = {
114  .name = "efi_watchdog",
115  .shutdown = efi_watchdog_shutdown,
116 };
#define WATCHDOG_CODE
Watchdog code (to be logged on watchdog timeout)
Definition: efi_watchdog.c:48
EFI_BOOT_SERVICES * BootServices
A pointer to the EFI Boot Services Table.
Definition: UefiSpec.h:2000
struct arbelprm_rc_send_wqe rc
Definition: arbel.h:14
EFI_SET_WATCHDOG_TIMER SetWatchdogTimer
Definition: UefiSpec.h:1894
#define TICKS_PER_SEC
Number of ticks per second.
Definition: timer.h:15
#define EEFI(efirc)
Convert an EFI status code to an iPXE status code.
Definition: efi.h:162
Error codes.
struct startup_fn efi_watchdog_startup_fn __startup_fn(STARTUP_EARLY)
Watchdog startup/shutdown function.
Retry timers.
#define STARTUP_EARLY
Early startup.
Definition: init.h:62
#define WATCHDOG_TIMEOUT_SECS
Watchdog timeout (in seconds)
Definition: efi_watchdog.c:45
#define DBGC(...)
Definition: compiler.h:505
#define TIMER_INIT(expired_fn)
Initialise a static timer.
Definition: retry.h:82
A retry timer.
Definition: retry.h:21
unsigned short CHAR16
Definition: ProcessorBind.h:59
iPXE timers
struct retry_timer efi_watchdog
Watchdog holdoff timer.
Definition: efi_watchdog.c:83
const char * name
Definition: init.h:42
A timer.
Definition: timer.h:28
A startup/shutdown function.
Definition: init.h:41
static void efi_watchdog_expired(struct retry_timer *timer, int over __unused)
Hold off watchdog timer.
Definition: efi_watchdog.c:59
#define WATCHDOG_HOLDOFF_SECS
Watchdog holdoff interval (in seconds)
Definition: efi_watchdog.c:42
char * strerror(int errno)
Retrieve string representation of error number.
Definition: strerror.c:78
EFI Boot Services Table.
Definition: UefiSpec.h:1836
EFI watchdog holdoff timer.
EFI API.
#define WATCHDOG_DATA
Watchdog data (to be logged on watchdog timeout)
Definition: efi_watchdog.c:51
void start_timer_fixed(struct retry_timer *timer, unsigned long timeout)
Start timer with a specified timeout.
Definition: retry.c:64
#define __unused
Declare a variable or data structure as unused.
Definition: compiler.h:573
#define DBGC2(...)
Definition: compiler.h:522
RETURN_STATUS EFI_STATUS
Function return status for EFI API.
Definition: UefiBaseType.h:35
static void efi_watchdog_shutdown(int booting)
Disable watching when shutting down to boot an operating system.
Definition: efi_watchdog.c:90
FILE_LICENCE(GPL2_OR_LATER_OR_UBDL)
EFI_SYSTEM_TABLE * efi_systab
struct arbelprm_port_state_change_st data
Message.
Definition: arbel.h:12
#define NULL
NULL pointer (VOID *)
Definition: Base.h:362
String functions.