odin-abl/OvmfPkg/SmbiosPlatformDxe/X86Xen.c
2021-07-23 18:06:52 +00:00

99 lines
2.5 KiB
C

/** @file
Detect Xen hvmloader SMBIOS data for usage by OVMF.
Copyright (c) 2011, Bei Guan <gbtju85@gmail.com>
Copyright (c) 2011, 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 "SmbiosPlatformDxe.h"
#include <Library/HobLib.h>
#include <Guid/XenInfo.h>
#define XEN_SMBIOS_PHYSICAL_ADDRESS 0x000EB000
#define XEN_SMBIOS_PHYSICAL_END 0x000F0000
/**
Validates the SMBIOS entry point structure
@param EntryPointStructure SMBIOS entry point structure
@retval TRUE The entry point structure is valid
@retval FALSE The entry point structure is not valid
**/
STATIC
BOOLEAN
IsEntryPointStructureValid (
IN SMBIOS_TABLE_ENTRY_POINT *EntryPointStructure
)
{
UINTN Index;
UINT8 Length;
UINT8 Checksum;
UINT8 *BytePtr;
BytePtr = (UINT8*) EntryPointStructure;
Length = EntryPointStructure->EntryPointLength;
Checksum = 0;
for (Index = 0; Index < Length; Index++) {
Checksum = Checksum + (UINT8) BytePtr[Index];
}
if (Checksum != 0) {
return FALSE;
} else {
return TRUE;
}
}
/**
Locates the Xen SMBIOS data if it exists
@return SMBIOS_TABLE_ENTRY_POINT Address of Xen SMBIOS data
**/
SMBIOS_TABLE_ENTRY_POINT *
GetXenSmbiosTables (
VOID
)
{
UINT8 *XenSmbiosPtr;
SMBIOS_TABLE_ENTRY_POINT *XenSmbiosEntryPointStructure;
EFI_HOB_GUID_TYPE *GuidHob;
//
// See if a XenInfo HOB is available
//
GuidHob = GetFirstGuidHob (&gEfiXenInfoGuid);
if (GuidHob == NULL) {
return NULL;
}
for (XenSmbiosPtr = (UINT8*)(UINTN) XEN_SMBIOS_PHYSICAL_ADDRESS;
XenSmbiosPtr < (UINT8*)(UINTN) XEN_SMBIOS_PHYSICAL_END;
XenSmbiosPtr += 0x10) {
XenSmbiosEntryPointStructure = (SMBIOS_TABLE_ENTRY_POINT *) XenSmbiosPtr;
if (!AsciiStrnCmp ((CHAR8 *) XenSmbiosEntryPointStructure->AnchorString, "_SM_", 4) &&
!AsciiStrnCmp ((CHAR8 *) XenSmbiosEntryPointStructure->IntermediateAnchorString, "_DMI_", 5) &&
IsEntryPointStructureValid (XenSmbiosEntryPointStructure)) {
return XenSmbiosEntryPointStructure;
}
}
return NULL;
}