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   SPDX-License-Identifier: BSD-2-Clause-Patent
   7 **/
   8
   9 #include "SmbiosPlatformDxe.h"
  10 #include <Library/QemuFwCfgLib.h>
  11 #include <Library/MemoryAllocationLib.h>
  12 #include <Library/PcdLib.h>
  13
  14 /**
  15   Locates and extracts the QEMU SMBIOS data if present in fw_cfg
  16
  17   @return                 Address of extracted QEMU SMBIOS data
  18
  19 **/
  20 UINT8 *
  21 GetQemuSmbiosTables (
  22   VOID
  23   )
  24 {
  25   EFI_STATUS               Status;
  26   FIRMWARE_CONFIG_ITEM     Tables;
  27   UINTN                    TablesSize;
  28   UINT8                    *QemuTables;
  29
  30   if (!PcdGetBool (PcdQemuSmbiosValidated)) {
  31     return NULL;
  32   }
  33
  34   Status = QemuFwCfgFindFile ("etc/smbios/smbios-tables", &Tables,
  35              &TablesSize);
  36   ASSERT_EFI_ERROR (Status);
  37   ASSERT (TablesSize > 0);
  38
  39   QemuTables = AllocatePool (TablesSize);
  40   if (QemuTables == NULL) {
  41     return NULL;
  42   }
  43
  44   QemuFwCfgSelectItem (Tables);
  45   QemuFwCfgReadBytes (TablesSize, QemuTables);
  46
  47   return QemuTables;
  48 }