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git.proxmox.com Git - mirror_edk2.git/blob - MdeModulePkg/Universal/RuntimeDxe/Crc32.c
3 Copyright (c) 2006, Intel Corporation
4 All rights reserved. This program and the accompanying materials
5 are licensed and made available under the terms and conditions of the BSD License
6 which accompanies this distribution. The full text of the license may be found at
7 http://opensource.org/licenses/bsd-license.php
9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18 CalculateCrc32 Boot Services as defined in DXE CIS.
20 This Boot Services is in the Runtime Driver because this service is
21 also required by SetVirtualAddressMap() when the EFI System Table and
22 EFI Runtime Services Table are converted from physical address to
23 virtual addresses. This requires that the 32-bit CRC be recomputed.
30 // The package level header files this module uses
34 UINT32 mCrcTable
[256];
38 RuntimeDriverCalculateCrc32 (
47 Calculate CRC32 for target data
51 Data - The target data.
52 DataSize - The target data size.
53 CrcOut - The CRC32 for target data.
57 EFI_SUCCESS - The CRC32 for target data is calculated successfully.
58 EFI_INVALID_PARAMETER - Some parameter is not valid, so the CRC32 is not
67 if (Data
== NULL
|| DataSize
== 0 || CrcOut
== NULL
) {
68 return EFI_INVALID_PARAMETER
;
72 for (Index
= 0, Ptr
= Data
; Index
< DataSize
; Index
++, Ptr
++) {
73 Crc
= (Crc
>> 8) ^ mCrcTable
[(UINT8
) Crc
^ *Ptr
];
76 *CrcOut
= Crc
^ 0xffffffff;
89 Reverse bits for 32bit data.
93 Value - the data to be reversed.
105 for (Index
= 0; Index
< 32; Index
++) {
106 if (Value
& (1 << Index
)) {
107 NewValue
= NewValue
| (1 << (31 - Index
));
115 RuntimeDriverInitializeCrc32Table (
122 Initialize CRC32 table.
138 for (TableEntry
= 0; TableEntry
< 256; TableEntry
++) {
139 Value
= ReverseBits ((UINT32
) TableEntry
);
140 for (Index
= 0; Index
< 8; Index
++) {
141 if (Value
& 0x80000000) {
142 Value
= (Value
<< 1) ^ 0x04c11db7;
148 mCrcTable
[TableEntry
] = ReverseBits (Value
);