1 /** @file 2 Watchdog Timer Architectural Protocol as defined in PI Specification VOLUME 2 DXE 3 4 Used to provide system watchdog timer services 5 6 Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR> 7 This program and the accompanying materials 8 are licensed and made available under the terms and conditions of the BSD License 9 which accompanies this distribution. The full text of the license may be found at 10 http://opensource.org/licenses/bsd-license.php 11 12 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 13 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 14 **/ 15 16 #ifndef __ARCH_PROTOCOL_WATCHDOG_TIMER_H__ 17 #define __ARCH_PROTOCOL_WATCHDOG_TIMER_H__ 18 19 /// 20 /// Global ID for the Watchdog Timer Architectural Protocol 21 /// 22 #define EFI_WATCHDOG_TIMER_ARCH_PROTOCOL_GUID \ 23 { 0x665E3FF5, 0x46CC, 0x11d4, {0x9A, 0x38, 0x00, 0x90, 0x27, 0x3F, 0xC1, 0x4D } } 24 25 /// 26 /// Declare forward reference for the Timer Architectural Protocol 27 /// 28 typedef struct _EFI_WATCHDOG_TIMER_ARCH_PROTOCOL EFI_WATCHDOG_TIMER_ARCH_PROTOCOL; 29 30 /** 31 A function of this type is called when the watchdog timer fires if a 32 handler has been registered. 33 34 @param Time The time in 100 ns units that has passed since the watchdog 35 timer was armed. For the notify function to be called, this 36 must be greater than TimerPeriod. 37 38 @return None. 39 40 **/ 41 typedef 42 VOID 43 (EFIAPI *EFI_WATCHDOG_TIMER_NOTIFY)( 44 IN UINT64 Time 45 ); 46 47 /** 48 This function registers a handler that is to be invoked when the watchdog 49 timer fires. By default, the EFI_WATCHDOG_TIMER protocol will call the 50 Runtime Service ResetSystem() when the watchdog timer fires. If a 51 NotifyFunction is registered, then the NotifyFunction will be called before 52 the Runtime Service ResetSystem() is called. If NotifyFunction is NULL, then 53 the watchdog handler is unregistered. If a watchdog handler is registered, 54 then EFI_SUCCESS is returned. If an attempt is made to register a handler 55 when a handler is already registered, then EFI_ALREADY_STARTED is returned. 56 If an attempt is made to uninstall a handler when a handler is not installed, 57 then return EFI_INVALID_PARAMETER. 58 59 @param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. 60 @param NotifyFunction The function to call when the watchdog timer fires. If this 61 is NULL, then the handler will be unregistered. 62 63 @retval EFI_SUCCESS The watchdog timer handler was registered or 64 unregistered. 65 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already 66 registered. 67 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not 68 previously registered. 69 70 **/ 71 typedef 72 EFI_STATUS 73 (EFIAPI *EFI_WATCHDOG_TIMER_REGISTER_HANDLER)( 74 IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, 75 IN EFI_WATCHDOG_TIMER_NOTIFY NotifyFunction 76 ); 77 78 /** 79 This function sets the amount of time to wait before firing the watchdog 80 timer to TimerPeriod 100 nS units. If TimerPeriod is 0, then the watchdog 81 timer is disabled. 82 83 @param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. 84 @param TimerPeriod The amount of time in 100 nS units to wait before the watchdog 85 timer is fired. If TimerPeriod is zero, then the watchdog 86 timer is disabled. 87 88 @retval EFI_SUCCESS The watchdog timer has been programmed to fire in Time 89 100 nS units. 90 @retval EFI_DEVICE_ERROR A watchdog timer could not be programmed due to a device 91 error. 92 93 **/ 94 typedef 95 EFI_STATUS 96 (EFIAPI *EFI_WATCHDOG_TIMER_SET_TIMER_PERIOD)( 97 IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, 98 IN UINT64 TimerPeriod 99 ); 100 101 /** 102 This function retrieves the amount of time the system will wait before firing 103 the watchdog timer. This period is returned in TimerPeriod, and EFI_SUCCESS 104 is returned. If TimerPeriod is NULL, then EFI_INVALID_PARAMETER is returned. 105 106 @param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. 107 @param TimerPeriod A pointer to the amount of time in 100 nS units that the system 108 will wait before the watchdog timer is fired. If TimerPeriod of 109 zero is returned, then the watchdog timer is disabled. 110 111 @retval EFI_SUCCESS The amount of time that the system will wait before 112 firing the watchdog timer was returned in TimerPeriod. 113 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL. 114 115 **/ 116 typedef 117 EFI_STATUS 118 (EFIAPI *EFI_WATCHDOG_TIMER_GET_TIMER_PERIOD)( 119 IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, 120 OUT UINT64 *TimerPeriod 121 ); 122 123 124 /// 125 /// This protocol provides the services required to implement the Boot Service 126 /// SetWatchdogTimer(). It provides a service to set the amount of time to wait 127 /// before firing the watchdog timer, and it also provides a service to register 128 /// a handler that is invoked when the watchdog timer fires. This protocol can 129 /// implement the watchdog timer by using the event and timer Boot Services, or 130 /// it can make use of custom hardware. When the watchdog timer fires, control 131 /// will be passed to a handler if one has been registered. If no handler has 132 /// been registered, or the registered handler returns, then the system will be 133 /// reset by calling the Runtime Service ResetSystem(). 134 /// 135 struct _EFI_WATCHDOG_TIMER_ARCH_PROTOCOL { 136 EFI_WATCHDOG_TIMER_REGISTER_HANDLER RegisterHandler; 137 EFI_WATCHDOG_TIMER_SET_TIMER_PERIOD SetTimerPeriod; 138 EFI_WATCHDOG_TIMER_GET_TIMER_PERIOD GetTimerPeriod; 139 }; 140 141 extern EFI_GUID gEfiWatchdogTimerArchProtocolGuid; 142 143 #endif 144 145