Ronak Kanabar | 1ae366f | 2023-06-07 01:21:56 +0530 | [diff] [blame^] | 1 | /** @file |
| 2 | Provides services to enable and disable periodic SMI handlers. |
| 3 | |
| 4 | Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved.<BR> |
| 5 | SPDX-License-Identifier: BSD-2-Clause-Patent |
| 6 | |
| 7 | **/ |
| 8 | |
| 9 | #ifndef __PERIODIC_SMI_LIB_H__ |
| 10 | #define __PERIODIC_SMI_LIB_H__ |
| 11 | |
| 12 | #define PERIODIC_SMI_LIBRARY_ANY_CPU 0xffffffff |
| 13 | |
| 14 | /** |
| 15 | This function returns a pointer to a table of supported periodic |
| 16 | SMI tick periods in 100 ns units sorted from largest to smallest. |
| 17 | The table contains a array of UINT64 values terminated by a tick |
| 18 | period value of 0. The returned table must be treated as read-only |
| 19 | data and must not be freed. |
| 20 | |
| 21 | @return A pointer to a table of UINT64 tick period values in |
| 22 | 100ns units sorted from largest to smallest terminated |
| 23 | by a tick period of 0. |
| 24 | |
| 25 | **/ |
| 26 | UINT64 * |
| 27 | EFIAPI |
| 28 | PeriodicSmiSupportedTickPeriod ( |
| 29 | VOID |
| 30 | ); |
| 31 | |
| 32 | /** |
| 33 | This function returns the time in 100ns units since the periodic SMI |
| 34 | handler function was called. If the periodic SMI handler was resumed |
| 35 | through PeriodicSmiYield(), then the time returned is the time in |
| 36 | 100ns units since PeriodicSmiYield() returned. |
| 37 | |
| 38 | @return The actual time in 100ns units that the periodic SMI handler |
| 39 | has been executing. If this function is not called from within |
| 40 | an enabled periodic SMI handler, then 0 is returned. |
| 41 | |
| 42 | **/ |
| 43 | UINT64 |
| 44 | EFIAPI |
| 45 | PeriodicSmiExecutionTime ( |
| 46 | VOID |
| 47 | ); |
| 48 | |
| 49 | /** |
| 50 | This function returns control back to the SMM Foundation. When the next |
| 51 | periodic SMI for the currently executing handler is triggered, the periodic |
| 52 | SMI handler will restarted from its registered DispatchFunction entry point. |
| 53 | If this function is not called from within an enabled periodic SMI handler, |
| 54 | then control is returned to the calling function. |
| 55 | |
| 56 | **/ |
| 57 | VOID |
| 58 | EFIAPI |
| 59 | PeriodicSmiExit ( |
| 60 | VOID |
| 61 | ); |
| 62 | |
| 63 | /** |
| 64 | This function yields control back to the SMM Foundation. When the next |
| 65 | periodic SMI for the currently executing handler is triggered, the periodic |
| 66 | SMI handler will be resumed and this function will return. Use of this |
| 67 | function requires a separate stack for the periodic SMI handler. A non zero |
| 68 | stack size must be specified in PeriodicSmiEnable() for this function to be |
| 69 | used. |
| 70 | |
| 71 | If the stack size passed into PeriodicSmiEnable() was zero, the 0 is returned. |
| 72 | |
| 73 | If this function is not called from within an enabled periodic SMI handler, |
| 74 | then 0 is returned. |
| 75 | |
| 76 | @return The actual time in 100ns units elapsed since this function was |
| 77 | called. A value of 0 indicates an unknown amount of time. |
| 78 | |
| 79 | **/ |
| 80 | UINT64 |
| 81 | EFIAPI |
| 82 | PeriodicSmiYield ( |
| 83 | VOID |
| 84 | ); |
| 85 | |
| 86 | /** |
| 87 | This function is a prototype for a periodic SMI handler function |
| 88 | that may be enabled with PeriodicSmiEnable() and disabled with |
| 89 | PeriodicSmiDisable(). |
| 90 | |
| 91 | @param[in] Context Content registered with PeriodicSmiEnable(). |
| 92 | @param[in] ElapsedTime The actual time in 100ns units elapsed since |
| 93 | this function was called. A value of 0 indicates |
| 94 | an unknown amount of time. |
| 95 | |
| 96 | **/ |
| 97 | typedef |
| 98 | VOID |
| 99 | (EFIAPI *PERIODIC_SMI_LIBRARY_HANDLER)( |
| 100 | IN CONST VOID *Context OPTIONAL, |
| 101 | IN UINT64 ElapsedTime |
| 102 | ); |
| 103 | |
| 104 | /** |
| 105 | This function enables a periodic SMI handler. |
| 106 | |
| 107 | @param[in, out] DispatchHandle A pointer to the handle associated with the |
| 108 | enabled periodic SMI handler. This is an |
| 109 | optional parameter that may be NULL. If it is |
| 110 | NULL, then the handle will not be returned, |
| 111 | which means that the periodic SMI handler can |
| 112 | never be disabled. |
| 113 | @param[in] DispatchFunction A pointer to a periodic SMI handler function. |
| 114 | @param[in] Context Optional content to pass into DispatchFunction. |
| 115 | @param[in] TickPeriod The requested tick period in 100ns units that |
| 116 | control should be given to the periodic SMI |
| 117 | handler. Must be one of the supported values |
| 118 | returned by PeriodicSmiSupportedPickPeriod(). |
| 119 | @param[in] Cpu Specifies the CPU that is required to execute |
| 120 | the periodic SMI handler. If Cpu is |
| 121 | PERIODIC_SMI_LIBRARY_ANY_CPU, then the periodic |
| 122 | SMI handler will always be executed on the SMST |
| 123 | CurrentlyExecutingCpu, which may vary across |
| 124 | periodic SMIs. If Cpu is between 0 and the SMST |
| 125 | NumberOfCpus, then the periodic SMI will always |
| 126 | be executed on the requested CPU. |
| 127 | @param[in] StackSize The size, in bytes, of the stack to allocate for |
| 128 | use by the periodic SMI handler. If 0, then the |
| 129 | default stack will be used. |
| 130 | |
| 131 | @retval EFI_INVALID_PARAMETER DispatchFunction is NULL. |
| 132 | @retval EFI_UNSUPPORTED TickPeriod is not a supported tick period. The |
| 133 | supported tick periods can be retrieved using |
| 134 | PeriodicSmiSupportedTickPeriod(). |
| 135 | @retval EFI_INVALID_PARAMETER Cpu is not PERIODIC_SMI_LIBRARY_ANY_CPU or in |
| 136 | the range 0 to SMST NumberOfCpus. |
| 137 | @retval EFI_OUT_OF_RESOURCES There are not enough resources to enable the |
| 138 | periodic SMI handler. |
| 139 | @retval EFI_OUT_OF_RESOURCES There are not enough resources to allocate the |
| 140 | stack specified by StackSize. |
| 141 | @retval EFI_SUCCESS The periodic SMI handler was enabled. |
| 142 | |
| 143 | **/ |
| 144 | EFI_STATUS |
| 145 | EFIAPI |
| 146 | PeriodicSmiEnable ( |
| 147 | IN OUT EFI_HANDLE *DispatchHandle OPTIONAL, |
| 148 | IN PERIODIC_SMI_LIBRARY_HANDLER DispatchFunction, |
| 149 | IN CONST VOID *Context OPTIONAL, |
| 150 | IN UINT64 TickPeriod, |
| 151 | IN UINTN Cpu, |
| 152 | IN UINTN StackSize |
| 153 | ); |
| 154 | |
| 155 | /** |
| 156 | This function disables a periodic SMI handler that has been previously |
| 157 | enabled with PeriodicSmiEnable(). |
| 158 | |
| 159 | @param[in] DispatchHandle A handle associated with a previously enabled periodic |
| 160 | SMI handler. This is an optional parameter that may |
| 161 | be NULL. If it is NULL, then the active periodic SMI |
| 162 | handlers is disabled. |
| 163 | |
| 164 | @retval FALSE DispatchHandle is NULL and there is no active periodic SMI handler. |
| 165 | @retval FALSE The periodic SMI handler specified by DispatchHandle has |
| 166 | not been enabled with PeriodicSmiEnable(). |
| 167 | @retval TRUE The periodic SMI handler specified by DispatchHandle has |
| 168 | been disabled. If DispatchHandle is NULL, then the active |
| 169 | periodic SMI handler has been disabled. |
| 170 | |
| 171 | **/ |
| 172 | BOOLEAN |
| 173 | EFIAPI |
| 174 | PeriodicSmiDisable ( |
| 175 | IN EFI_HANDLE DispatchHandle OPTIONAL |
| 176 | ); |
| 177 | |
| 178 | #endif |