/** @file Semaphore mechanism to indicate to the BSP that an AP has exited SMM after SMBASE relocation. Copyright (c) 2009 - 2015, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent **/ #include "PiSmmCpuDxeSmm.h" X86_ASSEMBLY_PATCH_LABEL gPatchSmmRelocationOriginalAddressPtr32; X86_ASSEMBLY_PATCH_LABEL gPatchRebasedFlagAddr32; UINTN mSmmRelocationOriginalAddress; volatile BOOLEAN *mRebasedFlag; /** AP Semaphore operation in 32-bit mode while BSP runs in 64-bit mode. **/ VOID SmmRelocationSemaphoreComplete32 ( VOID ); /** Hook return address of SMM Save State so that semaphore code can be executed immediately after AP exits SMM to indicate to the BSP that an AP has exited SMM after SMBASE relocation. @param[in] CpuIndex The processor index. @param[in] RebasedFlag A pointer to a flag that is set to TRUE immediately after AP exits SMM. **/ VOID SemaphoreHook ( IN UINTN CpuIndex, IN volatile BOOLEAN *RebasedFlag ) { SMRAM_SAVE_STATE_MAP *CpuState; UINTN TempValue; mRebasedFlag = RebasedFlag; PatchInstructionX86 ( gPatchRebasedFlagAddr32, (UINT32)(UINTN)mRebasedFlag, 4 ); CpuState = (SMRAM_SAVE_STATE_MAP *)(UINTN)(SMM_DEFAULT_SMBASE + SMRAM_SAVE_STATE_MAP_OFFSET); mSmmRelocationOriginalAddress = HookReturnFromSmm ( CpuIndex, CpuState, (UINT64)(UINTN)&SmmRelocationSemaphoreComplete32, (UINT64)(UINTN)&SmmRelocationSemaphoreComplete ); // // Use temp value to fix ICC compiler warning // TempValue = (UINTN)&mSmmRelocationOriginalAddress; PatchInstructionX86 ( gPatchSmmRelocationOriginalAddressPtr32, (UINT32)TempValue, 4 ); }