1 /** @file 2 SMM Periodic Timer Dispatch Protocol as defined in PI 1.1 Specification 3 Volume 4 System Management Mode Core Interface. 4 5 This protocol provides the parent dispatch service for the periodical timer SMI source generator. 6 7 Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR> 8 This program and the accompanying materials 9 are licensed and made available under the terms and conditions of the BSD License 10 which accompanies this distribution. The full text of the license may be found at 11 http://opensource.org/licenses/bsd-license.php 12 13 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 14 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 15 16 @par Revision Reference: 17 This protocol is from PI Version 1.1. 18 19 **/ 20 21 #ifndef _SMM_PERIODIC_TIMER_DISPATCH2_H_ 22 #define _SMM_PERIODIC_TIMER_DISPATCH2_H_ 23 24 #include <Pi/PiSmmCis.h> 25 26 #define EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL_GUID \ 27 { \ 28 0x4cec368e, 0x8e8e, 0x4d71, {0x8b, 0xe1, 0x95, 0x8c, 0x45, 0xfc, 0x8a, 0x53 } \ 29 } 30 31 /// 32 /// Example: A chipset supports periodic SMIs on every 64ms or 2 seconds. 33 /// A child wishes schedule a period SMI to fire on a period of 3 seconds, there 34 /// are several ways to approach the problem: 35 /// 1. The child may accept a 4 second periodic rate, in which case it registers with 36 /// Period = 40000 37 /// SmiTickInterval = 20000 38 /// The resulting SMI will occur every 2 seconds with the child called back on 39 /// every 2nd SMI. 40 /// NOTE: the same result would occur if the child set SmiTickInterval = 0. 41 /// 2. The child may choose the finer granularity SMI (64ms): 42 /// Period = 30000 43 /// SmiTickInterval = 640 44 /// The resulting SMI will occur every 64ms with the child called back on 45 /// every 47th SMI. 46 /// NOTE: the child driver should be aware that this will result in more 47 /// SMIs occuring during system runtime which can negatively impact system 48 /// performance. 49 /// 50 typedef struct { 51 /// 52 /// The minimum period of time in 100 nanosecond units that the child gets called. The 53 /// child will be called back after a time greater than the time Period. 54 /// 55 UINT64 Period; 56 /// 57 /// The period of time interval between SMIs. Children of this interface should use this 58 /// field when registering for periodic timer intervals when a finer granularity periodic 59 /// SMI is desired. 60 /// 61 UINT64 SmiTickInterval; 62 } EFI_SMM_PERIODIC_TIMER_REGISTER_CONTEXT; 63 64 /// 65 /// The DispatchFunction will be called with Context set to the same value as was passed into 66 /// Register() in RegisterContext and with CommBuffer pointing to an instance of 67 /// EFI_SMM_PERIODIC_TIMER_CONTEXT and CommBufferSize pointing to its size. 68 /// 69 typedef struct { 70 /// 71 /// ElapsedTime is the actual time in 100 nanosecond units elapsed since last called, a 72 /// value of 0 indicates an unknown amount of time. 73 /// 74 UINT64 ElapsedTime; 75 } EFI_SMM_PERIODIC_TIMER_CONTEXT; 76 77 typedef struct _EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL; 78 79 /** 80 Register a child SMI source dispatch function for SMM periodic timer. 81 82 This service registers a function (DispatchFunction) which will be called when at least the 83 amount of time specified by RegisterContext has elapsed. On return, DispatchHandle 84 contains a unique handle which may be used later to unregister the function using UnRegister(). 85 The DispatchFunction will be called with Context set to the same value as was passed into 86 this function in RegisterContext and with CommBuffer pointing to an instance of 87 EFI_SMM_PERIODIC_TIMER_CONTEXT and CommBufferSize pointing to its size. 88 89 @param[in] This Pointer to the EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL instance. 90 @param[in] DispatchFunction Function to register for handler when at least the specified amount 91 of time has elapsed. 92 @param[in] RegisterContext Pointer to the dispatch function's context. 93 The caller fills this context in before calling 94 the register function to indicate to the register 95 function the period at which the dispatch function 96 should be invoked. 97 @param[out] DispatchHandle Handle generated by the dispatcher to track the function instance. 98 99 @retval EFI_SUCCESS The dispatch function has been successfully 100 registered and the SMI source has been enabled. 101 @retval EFI_DEVICE_ERROR The driver was unable to enable the SMI source. 102 @retval EFI_INVALID_PARAMETER RegisterContext is invalid. The period input value 103 is not within valid range. 104 @retval EFI_OUT_OF_RESOURCES There is not enough memory (system or SMM) to manage this child. 105 **/ 106 typedef 107 EFI_STATUS 108 (EFIAPI *EFI_SMM_PERIODIC_TIMER_REGISTER2)( 109 IN CONST EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL *This, 110 IN EFI_SMM_HANDLER_ENTRY_POINT2 DispatchFunction, 111 IN CONST EFI_SMM_PERIODIC_TIMER_REGISTER_CONTEXT *RegisterContext, 112 OUT EFI_HANDLE *DispatchHandle 113 ); 114 115 /** 116 Unregisters a periodic timer service. 117 118 This service removes the handler associated with DispatchHandle so that it will no longer be 119 called when the time has elapsed. 120 121 @param[in] This Pointer to the EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL instance. 122 @param[in] DispatchHandle Handle of the service to remove. 123 124 @retval EFI_SUCCESS The service has been successfully removed. 125 @retval EFI_INVALID_PARAMETER The DispatchHandle was not valid. 126 **/ 127 typedef 128 EFI_STATUS 129 (EFIAPI *EFI_SMM_PERIODIC_TIMER_UNREGISTER2)( 130 IN CONST EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL *This, 131 IN EFI_HANDLE DispatchHandle 132 ); 133 134 /** 135 Returns the next SMI tick period supported by the chipset. 136 137 The order returned is from longest to shortest interval period. 138 139 @param[in] This Pointer to the EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL instance. 140 @param[in,out] SmiTickInterval Pointer to pointer of next shorter SMI interval 141 period supported by the child. This parameter works as a get-first, 142 get-next field.The first time this function is called, *SmiTickInterval 143 should be set to NULL to get the longest SMI interval.The returned 144 *SmiTickInterval should be passed in on subsequent calls to get the 145 next shorter interval period until *SmiTickInterval = NULL. 146 147 @retval EFI_SUCCESS The service returned successfully. 148 **/ 149 typedef 150 EFI_STATUS 151 (EFIAPI *EFI_SMM_PERIODIC_TIMER_INTERVAL2)( 152 IN CONST EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL *This, 153 IN OUT UINT64 **SmiTickInterval 154 ); 155 156 /// 157 /// Interface structure for the SMM Periodic Timer Dispatch Protocol 158 /// 159 /// This protocol provides the parent dispatch service for the periodical timer SMI source generator. 160 /// 161 struct _EFI_SMM_PERIODIC_TIMER_DISPATCH2_PROTOCOL { 162 EFI_SMM_PERIODIC_TIMER_REGISTER2 Register; 163 EFI_SMM_PERIODIC_TIMER_UNREGISTER2 UnRegister; 164 EFI_SMM_PERIODIC_TIMER_INTERVAL2 GetNextShorterInterval; 165 }; 166 167 extern EFI_GUID gEfiSmmPeriodicTimerDispatch2ProtocolGuid; 168 169 #endif 170 171