OvmfPkg/DecomprScratchEnd.fdf.inc

   1 ## @file
   2 #  This FDF include file computes the end of the scratch buffer used in
   3 #  DecompressMemFvs() [OvmfPkg/Sec/SecMain.c]. It is based on the decompressed
   4 #  (ie. original) size of the LZMA-compressed section of the one FFS file in
   5 #  the FVMAIN_COMPACT firmware volume.
   6 #
   7 #  Copyright (C) 2015, Red Hat, Inc.
   8 #
   9 #  SPDX-License-Identifier: BSD-2-Clause-Patent
  10 ##
  11
  12 # The GUID EE4E5898-3914-4259-9D6E-DC7BD79403CF means "LzmaCustomDecompress".
  13 # The decompressed output will have the following structure (see the file
  14 # "9E21FD93-9C72-4c15-8C4B-E77F1DB2D792SEC1.guided.dummy" in the
  15 # Build/Ovmf*/*/FV/Ffs/9E21FD93-9C72-4c15-8C4B-E77F1DB2D792/ directory):
  16 #
  17 # Size                 Contents
  18 # -------------------  --------------------------------------------------------
  19 #                   4  EFI_COMMON_SECTION_HEADER, stating size 124 (0x7C) and
  20 #                      type 0x19 (EFI_SECTION_RAW). The purpose of this section
  21 #                      is to pad the start of PEIFV to 128 bytes.
  22 #                 120  Zero bytes (padding).
  23 #
  24 #                   4  EFI_COMMON_SECTION_HEADER, stating size
  25 #                      (PcdOvmfPeiMemFvSize + 4), and type 0x17
  26 #                      (EFI_SECTION_FIRMWARE_VOLUME_IMAGE).
  27 # PcdOvmfPeiMemFvSize  PEIFV. Note that the above sizes pad the offset of this
  28 #                      object to 128 bytes. See also the "guided.dummy.txt"
  29 #                      file in the same directory.
  30 #
  31 #                   4  EFI_COMMON_SECTION_HEADER, stating size 12 (0xC) and
  32 #                      type 0x19 (EFI_SECTION_RAW). The purpose of this section
  33 #                      is to pad the start of DXEFV to 16 bytes.
  34 #                   8  Zero bytes (padding).
  35 #
  36 #                   4  EFI_COMMON_SECTION_HEADER, stating size
  37 #                      (PcdOvmfDxeMemFvSize + 4), and type 0x17
  38 #                      (EFI_SECTION_FIRMWARE_VOLUME_IMAGE).
  39 # PcdOvmfDxeMemFvSize  DXEFV. Note that the above sizes pad the offset of this
  40 #                      object to 16 bytes. See also the "guided.dummy.txt" file
  41 #                      in the same directory.
  42 #
  43 # The total size after decompression is (128 + PcdOvmfPeiMemFvSize + 16 +
  44 # PcdOvmfDxeMemFvSize).
  45
  46 DEFINE OUTPUT_SIZE = (128 + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfPeiMemFvSize + 16 + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDxeMemFvSize)
  47
  48 # LzmaCustomDecompressLib uses a constant scratch buffer size of 64KB; see
  49 # SCRATCH_BUFFER_REQUEST_SIZE in
  50 # "MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaDecompress.c".
  51
  52 DEFINE DECOMP_SCRATCH_SIZE = 0x00010000
  53
  54 # Note: when we use PcdOvmfDxeMemFvBase in this context, BaseTools have not yet
  55 # offset it with MEMFD's base address. For that reason we have to do it manually.
  56 #
  57 # The calculation below mirrors DecompressMemFvs() [OvmfPkg/Sec/SecMain.c].
  58
  59 DEFINE OUTPUT_BASE                   = ($(MEMFD_BASE_ADDRESS) + gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDxeMemFvBase + 0x00100000)
  60 DEFINE DECOMP_SCRATCH_BASE_UNALIGNED = ($(OUTPUT_BASE) + $(OUTPUT_SIZE))
  61 DEFINE DECOMP_SCRATCH_BASE_ALIGNMENT = 0x000FFFFF
  62 DEFINE DECOMP_SCRATCH_BASE_MASK      = 0xFFF00000
  63 DEFINE DECOMP_SCRATCH_BASE           = (($(DECOMP_SCRATCH_BASE_UNALIGNED) + $(DECOMP_SCRATCH_BASE_ALIGNMENT)) & $(DECOMP_SCRATCH_BASE_MASK))
  64
  65 SET gUefiOvmfPkgTokenSpaceGuid.PcdOvmfDecompressionScratchEnd = $(DECOMP_SCRATCH_BASE) + $(DECOMP_SCRATCH_SIZE)