OvmfPkg/AcpiPlatformDxe/QemuLoader.h

   1 /** @file
   2   Command structures for the QEMU FwCfg table loader interface.
   3
   4   Copyright (C) 2014, Red Hat, Inc.
   5
   6   This program and the accompanying materials are licensed and made available
   7   under the terms and conditions of the BSD License which accompanies this
   8   distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
  12   WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #ifndef __QEMU_LOADER_H__
  17 #define __QEMU_LOADER_H__
  18
  19 #include <Include/Base.h>
  20 #include <Library/QemuFwCfgLib.h>
  21
  22 //
  23 // The types and the documentation reflects the SeaBIOS interface. In OVMF we
  24 // use a minimal subset of it.
  25 //
  26 #define QEMU_LOADER_FNAME_SIZE QEMU_FW_CFG_FNAME_SIZE
  27
  28 //
  29 // We only look at the Allocate command, and only to get FwCfg filenames.
  30 //
  31 typedef enum {
  32   QemuLoaderCmdAllocate = 1,
  33   QemuLoaderCmdAddPointer,
  34   QemuLoaderCmdAddChecksum
  35 } QEMU_LOADER_COMMAND_TYPE;
  36
  37 typedef enum {
  38   QemuLoaderAllocHigh = 1,
  39   QemuLoaderAllocFSeg
  40 } QEMU_LOADER_ALLOC_ZONE;
  41
  42 #pragma pack (1)
  43 //
  44 // QemuLoaderCmdAllocate: download the fw_cfg file named File, to a buffer
  45 // allocated in the zone specified by Zone, aligned at a multiple of Alignment.
  46 //
  47 typedef struct {
  48   UINT8  File[QEMU_LOADER_FNAME_SIZE]; // NUL-terminated
  49   UINT32 Alignment;                    // power of two
  50   UINT8  Zone;                         // QEMU_LOADER_ALLOC_ZONE values
  51 } QEMU_LOADER_ALLOCATE;
  52
  53 //
  54 // QemuLoaderCmdAddPointer: the bytes at
  55 // [PointerOffset..PointerOffset+PointerSize) in the file PointerFile contain a
  56 // relative pointer (an offset) into PointeeFile. Increment the relative
  57 // pointer's value by the base address of where PointeeFile's contents have
  58 // been placed (when QemuLoaderCmdAllocate has been executed for PointeeFile).
  59 //
  60 typedef struct {
  61   UINT8  PointerFile[QEMU_LOADER_FNAME_SIZE]; // NUL-terminated
  62   UINT8  PointeeFile[QEMU_LOADER_FNAME_SIZE]; // NUL-terminated
  63   UINT32 PointerOffset;
  64   UINT8  PointerSize;                         // one of 1, 2, 4, 8
  65 } QEMU_LOADER_ADD_POINTER;
  66
  67 //
  68 // QemuLoaderCmdAddChecksum: calculate the UINT8 checksum (as per
  69 // CalculateChecksum8()) of the range [Start..Start+Length) in File. Store the
  70 // UINT8 result at ResultOffset in the same File.
  71 //
  72 typedef struct {
  73   UINT8  File[QEMU_LOADER_FNAME_SIZE]; // NUL-terminated
  74   UINT32 ResultOffset;
  75   UINT32 Start;
  76   UINT32 Length;
  77 } QEMU_LOADER_ADD_CHECKSUM;
  78
  79 typedef struct {
  80   UINT32 Type;                             // QEMU_LOADER_COMMAND_TYPE values
  81   union {
  82     QEMU_LOADER_ALLOCATE     Allocate;
  83     QEMU_LOADER_ADD_POINTER  AddPointer;
  84     QEMU_LOADER_ADD_CHECKSUM AddChecksum;
  85     UINT8                    Padding[124];
  86   } Command;
  87 } QEMU_LOADER_ENTRY;
  88 #pragma pack ()
  89
  90 #endif