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

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

/** @file\r
  OVMF support for QEMU system firmware flash device\r
\r
  Copyright (c) 2009 - 2013, Intel Corporation. All rights reserved.<BR>\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/MemEncryptSevLib.h>\r
#include <Library/PcdLib.h>\r
\r
#include "QemuFlash.h"\r
\r
#define WRITE_BYTE_CMD           0x10\r
#define BLOCK_ERASE_CMD          0x20\r
#define CLEAR_STATUS_CMD         0x50\r
#define READ_STATUS_CMD          0x70\r
#define READ_DEVID_CMD           0x90\r
#define BLOCK_ERASE_CONFIRM_CMD  0xd0\r
#define READ_ARRAY_CMD           0xff\r
\r
#define CLEARED_ARRAY_STATUS  0x00\r
\r
UINT8  *mFlashBase;\r
\r
STATIC UINTN  mFdBlockSize  = 0;\r
STATIC UINTN  mFdBlockCount = 0;\r
\r
STATIC\r
volatile UINT8 *\r
QemuFlashPtr (\r
  IN        EFI_LBA  Lba,\r
  IN        UINTN    Offset\r
  )\r
{\r
  return mFlashBase + ((UINTN)Lba * mFdBlockSize) + Offset;\r
}\r
\r
/**\r
  Determines if the QEMU flash memory device is present.\r
\r
  @retval FALSE   The QEMU flash device is not present.\r
  @retval TRUE    The QEMU flash device is present.\r
\r
**/\r
STATIC\r
BOOLEAN\r
QemuFlashDetected (\r
  VOID\r
  )\r
{\r
  BOOLEAN         FlashDetected;\r
  volatile UINT8  *Ptr;\r
\r
  UINTN  Offset;\r
  UINT8  OriginalUint8;\r
  UINT8  ProbeUint8;\r
\r
  FlashDetected = FALSE;\r
  Ptr           = QemuFlashPtr (0, 0);\r
\r
  for (Offset = 0; Offset < mFdBlockSize; Offset++) {\r
    Ptr        = QemuFlashPtr (0, Offset);\r
    ProbeUint8 = *Ptr;\r
    if ((ProbeUint8 != CLEAR_STATUS_CMD) &&\r
        (ProbeUint8 != READ_STATUS_CMD) &&\r
        (ProbeUint8 != CLEARED_ARRAY_STATUS))\r
    {\r
      break;\r
    }\r
  }\r
\r
  if (Offset >= mFdBlockSize) {\r
    DEBUG ((DEBUG_INFO, "QEMU Flash: Failed to find probe location\n"));\r
    return FALSE;\r
  }\r
\r
  DEBUG ((DEBUG_INFO, "QEMU Flash: Attempting flash detection at %p\n", Ptr));\r
\r
  if (MemEncryptSevEsIsEnabled ()) {\r
    //\r
    // When SEV-ES is enabled, the check below can result in an infinite\r
    // loop with respect to a nested page fault. When the memslot is mapped\r
    // read-only, the nested page table entry is read-only. The check below\r
    // will cause a nested page fault that cannot be emulated, causing\r
    // the instruction to retried over and over. For SEV-ES, acknowledge that\r
    // the FD appears as ROM and not as FLASH, but report FLASH anyway because\r
    // FLASH behavior can be simulated using VMGEXIT.\r
    //\r
    DEBUG ((\r
      DEBUG_INFO,\r
      "QEMU Flash: SEV-ES enabled, assuming FD behaves as FLASH\n"\r
      ));\r
    return TRUE;\r
  }\r
\r
  OriginalUint8 = *Ptr;\r
  *Ptr          = CLEAR_STATUS_CMD;\r
  ProbeUint8    = *Ptr;\r
  if ((OriginalUint8 != CLEAR_STATUS_CMD) &&\r
      (ProbeUint8 == CLEAR_STATUS_CMD))\r
  {\r
    DEBUG ((DEBUG_INFO, "QemuFlashDetected => FD behaves as RAM\n"));\r
    *Ptr = OriginalUint8;\r
  } else {\r
    *Ptr       = READ_STATUS_CMD;\r
    ProbeUint8 = *Ptr;\r
    if (ProbeUint8 == OriginalUint8) {\r
      DEBUG ((DEBUG_INFO, "QemuFlashDetected => FD behaves as ROM\n"));\r
    } else if (ProbeUint8 == READ_STATUS_CMD) {\r
      DEBUG ((DEBUG_INFO, "QemuFlashDetected => FD behaves as RAM\n"));\r
      *Ptr = OriginalUint8;\r
    } else if (ProbeUint8 == CLEARED_ARRAY_STATUS) {\r
      DEBUG ((DEBUG_INFO, "QemuFlashDetected => FD behaves as FLASH\n"));\r
      FlashDetected = TRUE;\r
      *Ptr          = READ_ARRAY_CMD;\r
    }\r
  }\r
\r
  DEBUG ((\r
    DEBUG_INFO,\r
    "QemuFlashDetected => %a\n",\r
    FlashDetected ? "Yes" : "No"\r
    ));\r
  return FlashDetected;\r
}\r
\r
/**\r
  Read from QEMU Flash\r
\r
  @param[in] Lba      The starting logical block index to read from.\r
  @param[in] Offset   Offset into the block at which to begin reading.\r
  @param[in] NumBytes On input, indicates the requested read size. On\r
                      output, indicates the actual number of bytes read\r
  @param[in] Buffer   Pointer to the buffer to read into.\r
\r
**/\r
EFI_STATUS\r
QemuFlashRead (\r
  IN        EFI_LBA  Lba,\r
  IN        UINTN    Offset,\r
  IN        UINTN    *NumBytes,\r
  IN        UINT8    *Buffer\r
  )\r
{\r
  UINT8  *Ptr;\r
\r
  //\r
  // Only write to the first 64k. We don't bother saving the FTW Spare\r
  // block into the flash memory.\r
  //\r
  if (Lba >= mFdBlockCount) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Get flash address\r
  //\r
  Ptr = (UINT8 *)QemuFlashPtr (Lba, Offset);\r
\r
  CopyMem (Buffer, Ptr, *NumBytes);\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Write to QEMU Flash\r
\r
  @param[in] Lba      The starting logical block index to write to.\r
  @param[in] Offset   Offset into the block at which to begin writing.\r
  @param[in] NumBytes On input, indicates the requested write size. On\r
                      output, indicates the actual number of bytes written\r
  @param[in] Buffer   Pointer to the data to write.\r
\r
**/\r
EFI_STATUS\r
QemuFlashWrite (\r
  IN        EFI_LBA  Lba,\r
  IN        UINTN    Offset,\r
  IN        UINTN    *NumBytes,\r
  IN        UINT8    *Buffer\r
  )\r
{\r
  volatile UINT8  *Ptr;\r
  UINTN           Loop;\r
\r
  //\r
  // Only write to the first 64k. We don't bother saving the FTW Spare\r
  // block into the flash memory.\r
  //\r
  if (Lba >= mFdBlockCount) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  //\r
  // Program flash\r
  //\r
  Ptr = QemuFlashPtr (Lba, Offset);\r
  for (Loop = 0; Loop < *NumBytes; Loop++) {\r
    QemuFlashPtrWrite (Ptr, WRITE_BYTE_CMD);\r
    QemuFlashPtrWrite (Ptr, Buffer[Loop]);\r
\r
    Ptr++;\r
  }\r
\r
  //\r
  // Restore flash to read mode\r
  //\r
  if (*NumBytes > 0) {\r
    QemuFlashPtrWrite (Ptr - 1, READ_ARRAY_CMD);\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Erase a QEMU Flash block\r
\r
  @param Lba    The logical block index to erase.\r
\r
**/\r
EFI_STATUS\r
QemuFlashEraseBlock (\r
  IN   EFI_LBA  Lba\r
  )\r
{\r
  volatile UINT8  *Ptr;\r
\r
  if (Lba >= mFdBlockCount) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  Ptr = QemuFlashPtr (Lba, 0);\r
  QemuFlashPtrWrite (Ptr, BLOCK_ERASE_CMD);\r
  QemuFlashPtrWrite (Ptr, BLOCK_ERASE_CONFIRM_CMD);\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Initializes QEMU flash memory support\r
\r
  @retval EFI_WRITE_PROTECTED   The QEMU flash device is not present.\r
  @retval EFI_SUCCESS           The QEMU flash device is supported.\r
\r
**/\r
EFI_STATUS\r
QemuFlashInitialize (\r
  VOID\r
  )\r
{\r
  mFlashBase   = (UINT8 *)(UINTN)PcdGet32 (PcdOvmfFdBaseAddress);\r
  mFdBlockSize = PcdGet32 (PcdOvmfFirmwareBlockSize);\r
  ASSERT (PcdGet32 (PcdOvmfFirmwareFdSize) % mFdBlockSize == 0);\r
  mFdBlockCount = PcdGet32 (PcdOvmfFirmwareFdSize) / mFdBlockSize;\r
\r
  //\r
  // execute module specific hooks before probing the flash\r
  //\r
  QemuFlashBeforeProbe (\r
    (EFI_PHYSICAL_ADDRESS)(UINTN)mFlashBase,\r
    mFdBlockSize,\r
    mFdBlockCount\r
    );\r
\r
  if (!QemuFlashDetected ()) {\r
    ASSERT (!FeaturePcdGet (PcdSmmSmramRequire));\r
    return EFI_WRITE_PROTECTED;\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r