OvmfPkg/SmbiosPlatformDxe/Qemu.c

   1 /** @file
   2   Find and extract QEMU SMBIOS data from fw_cfg.
   3
   4   Copyright (C) 2014, Gabriel L. Somlo <somlo@cmu.edu>
   5
   6   This program and the accompanying materials are licensed and made
   7   available under the terms and conditions of the BSD License which
   8   accompanies this distribution.   The full text of the license may
   9   be found at http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13 **/
  14
  15 #include "SmbiosPlatformDxe.h"
  16 #include <Library/QemuFwCfgLib.h>
  17 #include <Library/MemoryAllocationLib.h>
  18 #include <Library/PcdLib.h>
  19
  20 /**
  21   Locates and extracts the QEMU SMBIOS data if present in fw_cfg
  22
  23   @return                 Address of extracted QEMU SMBIOS data
  24
  25 **/
  26 UINT8 *
  27 GetQemuSmbiosTables (
  28   VOID
  29   )
  30 {
  31   EFI_STATUS               Status;
  32   FIRMWARE_CONFIG_ITEM     Tables;
  33   UINTN                    TablesSize;
  34   UINT8                    *QemuTables;
  35
  36   if (!PcdGetBool (PcdQemuSmbiosValidated)) {
  37     return NULL;
  38   }
  39
  40   Status = QemuFwCfgFindFile ("etc/smbios/smbios-tables", &Tables,
  41              &TablesSize);
  42   ASSERT_EFI_ERROR (Status);
  43   ASSERT (TablesSize > 0);
  44
  45   QemuTables = AllocatePool (TablesSize);
  46   if (QemuTables == NULL) {
  47     return NULL;
  48   }
  49
  50   QemuFwCfgSelectItem (Tables);
  51   QemuFwCfgReadBytes (TablesSize, QemuTables);
  52
  53   return QemuTables;
  54 }