UefiCpuPkg: Move AsmRelocateApLoopStart from Mpfuncs.nasm to AmdSev.nasm

[mirror_edk2.git] / OvmfPkg / QemuFlashFvbServicesRuntimeDxe / QemuFlashSmm.c

/** @file\r
  Define the module hooks used while probing the QEMU flash device.\r
\r
  Copyright (C) 2018, Advanced Micro Devices. All rights reserved.\r
\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <Library/BaseMemoryLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/PcdLib.h>\r
#include <Library/MemEncryptSevLib.h>\r
\r
#include "QemuFlash.h"\r
\r
VOID\r
QemuFlashBeforeProbe (\r
  IN  EFI_PHYSICAL_ADDRESS  BaseAddress,\r
  IN  UINTN                 FdBlockSize,\r
  IN  UINTN                 FdBlockCount\r
  )\r
{\r
  EFI_STATUS  Status;\r
\r
  ASSERT (FeaturePcdGet (PcdSmmSmramRequire));\r
\r
  if (!MemEncryptSevIsEnabled ()) {\r
    return;\r
  }\r
\r
  //\r
  // When SEV is enabled, AmdSevDxe runs early in DXE phase and clears the\r
  // C-bit from the NonExistent entry -- which is later split and accommodate\r
  // the flash MMIO but the driver runs in non SMM context hence it cleared the\r
  // flash ranges from non SMM page table. When SMM is enabled, the flash\r
  // services are accessed from the SMM mode hence we explicitly clear the\r
  // C-bit on flash ranges from SMM page table.\r
  //\r
\r
  Status = MemEncryptSevClearMmioPageEncMask (\r
             0,\r
             BaseAddress,\r
             EFI_SIZE_TO_PAGES (FdBlockSize * FdBlockCount)\r
             );\r
  ASSERT_EFI_ERROR (Status);\r
}\r
\r
/**\r
  Write to QEMU Flash\r
\r
  @param[in] Ptr    Pointer to the location to write.\r
  @param[in] Value  The value to write.\r
\r
**/\r
VOID\r
QemuFlashPtrWrite (\r
  IN        volatile UINT8  *Ptr,\r
  IN        UINT8           Value\r
  )\r
{\r
  *Ptr = Value;\r
}\r