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 - 2018, Intel Corporation. All rights reserved.<BR> 7 SPDX-License-Identifier: BSD-2-Clause-Patent 8 **/ 9 10 #ifndef __ARCH_PROTOCOL_WATCHDOG_TIMER_H__ 11 #define __ARCH_PROTOCOL_WATCHDOG_TIMER_H__ 12 13 /// 14 /// Global ID for the Watchdog Timer Architectural Protocol 15 /// 16 #define EFI_WATCHDOG_TIMER_ARCH_PROTOCOL_GUID \ 17 { 0x665E3FF5, 0x46CC, 0x11d4, {0x9A, 0x38, 0x00, 0x90, 0x27, 0x3F, 0xC1, 0x4D } } 18 19 /// 20 /// Declare forward reference for the Timer Architectural Protocol 21 /// 22 typedef struct _EFI_WATCHDOG_TIMER_ARCH_PROTOCOL EFI_WATCHDOG_TIMER_ARCH_PROTOCOL; 23 24 /** 25 A function of this type is called when the watchdog timer fires if a 26 handler has been registered. 27 28 @param Time The time in 100 ns units that has passed since the watchdog 29 timer was armed. For the notify function to be called, this 30 must be greater than TimerPeriod. 31 32 @return None. 33 34 **/ 35 typedef 36 VOID 37 (EFIAPI *EFI_WATCHDOG_TIMER_NOTIFY)( 38 IN UINT64 Time 39 ); 40 41 /** 42 This function registers a handler that is to be invoked when the watchdog 43 timer fires. By default, the EFI_WATCHDOG_TIMER protocol will call the 44 Runtime Service ResetSystem() when the watchdog timer fires. If a 45 NotifyFunction is registered, then the NotifyFunction will be called before 46 the Runtime Service ResetSystem() is called. If NotifyFunction is NULL, then 47 the watchdog handler is unregistered. If a watchdog handler is registered, 48 then EFI_SUCCESS is returned. If an attempt is made to register a handler 49 when a handler is already registered, then EFI_ALREADY_STARTED is returned. 50 If an attempt is made to uninstall a handler when a handler is not installed, 51 then return EFI_INVALID_PARAMETER. 52 53 @param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. 54 @param NotifyFunction The function to call when the watchdog timer fires. If this 55 is NULL, then the handler will be unregistered. 56 57 @retval EFI_SUCCESS The watchdog timer handler was registered or 58 unregistered. 59 @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already 60 registered. 61 @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not 62 previously registered. 63 64 **/ 65 typedef 66 EFI_STATUS 67 (EFIAPI *EFI_WATCHDOG_TIMER_REGISTER_HANDLER)( 68 IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, 69 IN EFI_WATCHDOG_TIMER_NOTIFY NotifyFunction 70 ); 71 72 /** 73 This function sets the amount of time to wait before firing the watchdog 74 timer to TimerPeriod 100 nS units. If TimerPeriod is 0, then the watchdog 75 timer is disabled. 76 77 @param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. 78 @param TimerPeriod The amount of time in 100 nS units to wait before the watchdog 79 timer is fired. If TimerPeriod is zero, then the watchdog 80 timer is disabled. 81 82 @retval EFI_SUCCESS The watchdog timer has been programmed to fire in Time 83 100 nS units. 84 @retval EFI_DEVICE_ERROR A watchdog timer could not be programmed due to a device 85 error. 86 87 **/ 88 typedef 89 EFI_STATUS 90 (EFIAPI *EFI_WATCHDOG_TIMER_SET_TIMER_PERIOD)( 91 IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, 92 IN UINT64 TimerPeriod 93 ); 94 95 /** 96 This function retrieves the amount of time the system will wait before firing 97 the watchdog timer. This period is returned in TimerPeriod, and EFI_SUCCESS 98 is returned. If TimerPeriod is NULL, then EFI_INVALID_PARAMETER is returned. 99 100 @param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. 101 @param TimerPeriod A pointer to the amount of time in 100 nS units that the system 102 will wait before the watchdog timer is fired. If TimerPeriod of 103 zero is returned, then the watchdog timer is disabled. 104 105 @retval EFI_SUCCESS The amount of time that the system will wait before 106 firing the watchdog timer was returned in TimerPeriod. 107 @retval EFI_INVALID_PARAMETER TimerPeriod is NULL. 108 109 **/ 110 typedef 111 EFI_STATUS 112 (EFIAPI *EFI_WATCHDOG_TIMER_GET_TIMER_PERIOD)( 113 IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, 114 OUT UINT64 *TimerPeriod 115 ); 116 117 /// 118 /// This protocol provides the services required to implement the Boot Service 119 /// SetWatchdogTimer(). It provides a service to set the amount of time to wait 120 /// before firing the watchdog timer, and it also provides a service to register 121 /// a handler that is invoked when the watchdog timer fires. This protocol can 122 /// implement the watchdog timer by using the event and timer Boot Services, or 123 /// it can make use of custom hardware. When the watchdog timer fires, control 124 /// will be passed to a handler if one has been registered. If no handler has 125 /// been registered, or the registered handler returns, then the system will be 126 /// reset by calling the Runtime Service ResetSystem(). 127 /// 128 struct _EFI_WATCHDOG_TIMER_ARCH_PROTOCOL { 129 EFI_WATCHDOG_TIMER_REGISTER_HANDLER RegisterHandler; 130 EFI_WATCHDOG_TIMER_SET_TIMER_PERIOD SetTimerPeriod; 131 EFI_WATCHDOG_TIMER_GET_TIMER_PERIOD GetTimerPeriod; 132 }; 133 134 extern EFI_GUID gEfiWatchdogTimerArchProtocolGuid; 135 136 #endif 137