mirror_edk2/OvmfPkg/Library/SmbiosVersionLib/DetectSmbiosVersionLib.c
Laszlo Ersek 92dc0bb23c OvmfPkg: SmbiosPlatformDxe: eliminate duplicate entry point validation
At this point all platforms that use OvmfPkg/SmbiosPlatformDxe in edk2,
namely ArmVirtQemu.dsc and OvmfPkg*.dsc, have been migrated to
SmbiosVersionLib. Therefore SmbiosPlatformDxe itself can forego verifying
QEMU's SMBIOS entry point; if SmbiosVersionLib's validation was
successful, it should just rely on that.

(Note that SmbiosPlatformDxe has a depex on EFI_SMBIOS_PROTOCOL, installed
by SmbiosDxe, containing SmbiosVersionLib, therefore the set/get order of
PcdQemuSmbiosValidated is ensured.)

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Wei Huang <wei@redhat.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Gabriel L. Somlo <somlo@cmu.edu>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18180 6f19259b-4bc3-4df7-8a09-765794883524
2015-08-06 10:14:03 +00:00

91 lines
2.7 KiB
C

/** @file
A hook-in library for MdeModulePkg/Universal/SmbiosDxe, in order to set
gEfiMdeModulePkgTokenSpaceGuid.PcdSmbiosVersion (and possibly other PCDs)
just before SmbiosDxe consumes them.
Copyright (C) 2013, 2015, Red Hat, Inc.
Copyright (c) 2008 - 2012, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials are licensed and made available
under the terms and conditions of the BSD License which accompanies this
distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, WITHOUT
WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include <IndustryStandard/SmBios.h>
#include <Base.h>
#include <Library/BaseMemoryLib.h>
#include <Library/DebugLib.h>
#include <Library/PcdLib.h>
#include <Library/QemuFwCfgLib.h>
typedef union {
SMBIOS_TABLE_ENTRY_POINT V2;
} QEMU_SMBIOS_ANCHOR;
RETURN_STATUS
EFIAPI
DetectSmbiosVersion (
VOID
)
{
FIRMWARE_CONFIG_ITEM Anchor, Tables;
UINTN AnchorSize, TablesSize;
QEMU_SMBIOS_ANCHOR QemuAnchor;
UINT16 SmbiosVersion;
if (PcdGetBool (PcdQemuSmbiosValidated)) {
//
// Some other module, linked against this library, has already performed
// the task at hand. This should never happen, but it's easy to handle;
// just exit early.
//
return RETURN_SUCCESS;
}
if (RETURN_ERROR (QemuFwCfgFindFile (
"etc/smbios/smbios-anchor", &Anchor, &AnchorSize)) ||
RETURN_ERROR (QemuFwCfgFindFile (
"etc/smbios/smbios-tables", &Tables, &TablesSize)) ||
TablesSize == 0) {
return RETURN_SUCCESS;
}
QemuFwCfgSelectItem (Anchor);
switch (AnchorSize) {
case sizeof QemuAnchor.V2:
QemuFwCfgReadBytes (AnchorSize, &QemuAnchor);
if (QemuAnchor.V2.MajorVersion != 2 ||
QemuAnchor.V2.TableLength != TablesSize ||
CompareMem (QemuAnchor.V2.AnchorString, "_SM_", 4) != 0 ||
CompareMem (QemuAnchor.V2.IntermediateAnchorString, "_DMI_", 5) != 0) {
return RETURN_SUCCESS;
}
SmbiosVersion = (UINT16)(QemuAnchor.V2.MajorVersion << 8 |
QemuAnchor.V2.MinorVersion);
break;
default:
return RETURN_SUCCESS;
}
DEBUG ((EFI_D_INFO, "%a: SMBIOS version from QEMU: 0x%04x\n", __FUNCTION__,
SmbiosVersion));
PcdSet16 (PcdSmbiosVersion, SmbiosVersion);
//
// SMBIOS platform drivers can now fetch and install
// "etc/smbios/smbios-tables" from QEMU.
//
PcdSetBool (PcdQemuSmbiosValidated, TRUE);
return RETURN_SUCCESS;
}