| /** @file |
| Provides services to enable and disable periodic SMI handlers. |
| |
| Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved.<BR> |
| SPDX-License-Identifier: BSD-2-Clause-Patent |
| |
| **/ |
| |
| #ifndef __PERIODIC_SMI_LIB_H__ |
| #define __PERIODIC_SMI_LIB_H__ |
| |
| #define PERIODIC_SMI_LIBRARY_ANY_CPU 0xffffffff |
| |
| /** |
| This function returns a pointer to a table of supported periodic |
| SMI tick periods in 100 ns units sorted from largest to smallest. |
| The table contains a array of UINT64 values terminated by a tick |
| period value of 0. The returned table must be treated as read-only |
| data and must not be freed. |
| |
| @return A pointer to a table of UINT64 tick period values in |
| 100ns units sorted from largest to smallest terminated |
| by a tick period of 0. |
| |
| **/ |
| UINT64 * |
| EFIAPI |
| PeriodicSmiSupportedTickPeriod ( |
| VOID |
| ); |
| |
| /** |
| This function returns the time in 100ns units since the periodic SMI |
| handler function was called. If the periodic SMI handler was resumed |
| through PeriodicSmiYield(), then the time returned is the time in |
| 100ns units since PeriodicSmiYield() returned. |
| |
| @return The actual time in 100ns units that the periodic SMI handler |
| has been executing. If this function is not called from within |
| an enabled periodic SMI handler, then 0 is returned. |
| |
| **/ |
| UINT64 |
| EFIAPI |
| PeriodicSmiExecutionTime ( |
| VOID |
| ); |
| |
| /** |
| This function returns control back to the SMM Foundation. When the next |
| periodic SMI for the currently executing handler is triggered, the periodic |
| SMI handler will restarted from its registered DispatchFunction entry point. |
| If this function is not called from within an enabled periodic SMI handler, |
| then control is returned to the calling function. |
| |
| **/ |
| VOID |
| EFIAPI |
| PeriodicSmiExit ( |
| VOID |
| ); |
| |
| /** |
| This function yields control back to the SMM Foundation. When the next |
| periodic SMI for the currently executing handler is triggered, the periodic |
| SMI handler will be resumed and this function will return. Use of this |
| function requires a separate stack for the periodic SMI handler. A non zero |
| stack size must be specified in PeriodicSmiEnable() for this function to be |
| used. |
| |
| If the stack size passed into PeriodicSmiEnable() was zero, the 0 is returned. |
| |
| If this function is not called from within an enabled periodic SMI handler, |
| then 0 is returned. |
| |
| @return The actual time in 100ns units elapsed since this function was |
| called. A value of 0 indicates an unknown amount of time. |
| |
| **/ |
| UINT64 |
| EFIAPI |
| PeriodicSmiYield ( |
| VOID |
| ); |
| |
| /** |
| This function is a prototype for a periodic SMI handler function |
| that may be enabled with PeriodicSmiEnable() and disabled with |
| PeriodicSmiDisable(). |
| |
| @param[in] Context Content registered with PeriodicSmiEnable(). |
| @param[in] ElapsedTime The actual time in 100ns units elapsed since |
| this function was called. A value of 0 indicates |
| an unknown amount of time. |
| |
| **/ |
| typedef |
| VOID |
| (EFIAPI *PERIODIC_SMI_LIBRARY_HANDLER) ( |
| IN CONST VOID *Context OPTIONAL, |
| IN UINT64 ElapsedTime |
| ); |
| |
| /** |
| This function enables a periodic SMI handler. |
| |
| @param[in, out] DispatchHandle A pointer to the handle associated with the |
| enabled periodic SMI handler. This is an |
| optional parameter that may be NULL. If it is |
| NULL, then the handle will not be returned, |
| which means that the periodic SMI handler can |
| never be disabled. |
| @param[in] DispatchFunction A pointer to a periodic SMI handler function. |
| @param[in] Context Optional content to pass into DispatchFunction. |
| @param[in] TickPeriod The requested tick period in 100ns units that |
| control should be given to the periodic SMI |
| handler. Must be one of the supported values |
| returned by PeriodicSmiSupportedPickPeriod(). |
| @param[in] Cpu Specifies the CPU that is required to execute |
| the periodic SMI handler. If Cpu is |
| PERIODIC_SMI_LIBRARY_ANY_CPU, then the periodic |
| SMI handler will always be executed on the SMST |
| CurrentlyExecutingCpu, which may vary across |
| periodic SMIs. If Cpu is between 0 and the SMST |
| NumberOfCpus, then the periodic SMI will always |
| be executed on the requested CPU. |
| @param[in] StackSize The size, in bytes, of the stack to allocate for |
| use by the periodic SMI handler. If 0, then the |
| default stack will be used. |
| |
| @retval EFI_INVALID_PARAMETER DispatchFunction is NULL. |
| @retval EFI_UNSUPPORTED TickPeriod is not a supported tick period. The |
| supported tick periods can be retrieved using |
| PeriodicSmiSupportedTickPeriod(). |
| @retval EFI_INVALID_PARAMETER Cpu is not PERIODIC_SMI_LIBRARY_ANY_CPU or in |
| the range 0 to SMST NumberOfCpus. |
| @retval EFI_OUT_OF_RESOURCES There are not enough resources to enable the |
| periodic SMI handler. |
| @retval EFI_OUT_OF_RESOURCES There are not enough resources to allocate the |
| stack specified by StackSize. |
| @retval EFI_SUCCESS The periodic SMI handler was enabled. |
| |
| **/ |
| EFI_STATUS |
| EFIAPI |
| PeriodicSmiEnable ( |
| IN OUT EFI_HANDLE *DispatchHandle, OPTIONAL |
| IN PERIODIC_SMI_LIBRARY_HANDLER DispatchFunction, |
| IN CONST VOID *Context, OPTIONAL |
| IN UINT64 TickPeriod, |
| IN UINTN Cpu, |
| IN UINTN StackSize |
| ); |
| |
| /** |
| This function disables a periodic SMI handler that has been previously |
| enabled with PeriodicSmiEnable(). |
| |
| @param[in] DispatchHandle A handle associated with a previously enabled periodic |
| SMI handler. This is an optional parameter that may |
| be NULL. If it is NULL, then the active periodic SMI |
| handlers is disabled. |
| |
| @retval FALSE DispatchHandle is NULL and there is no active periodic SMI handler. |
| @retval FALSE The periodic SMI handler specified by DispatchHandle has |
| not been enabled with PeriodicSmiEnable(). |
| @retval TRUE The periodic SMI handler specified by DispatchHandle has |
| been disabled. If DispatchHandle is NULL, then the active |
| periodic SMI handler has been disabled. |
| |
| **/ |
| BOOLEAN |
| EFIAPI |
| PeriodicSmiDisable ( |
| IN EFI_HANDLE DispatchHandle OPTIONAL |
| ); |
| |
| #endif |