diff options
Diffstat (limited to 'MdeModulePkg/Core/RuntimeDxe/Crc32.c')
-rw-r--r-- | MdeModulePkg/Core/RuntimeDxe/Crc32.c | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/MdeModulePkg/Core/RuntimeDxe/Crc32.c b/MdeModulePkg/Core/RuntimeDxe/Crc32.c new file mode 100644 index 0000000000..910738eb52 --- /dev/null +++ b/MdeModulePkg/Core/RuntimeDxe/Crc32.c @@ -0,0 +1,150 @@ +/*++
+
+Copyright (c) 2006, Intel Corporation
+All rights reserved. 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.
+
+Module Name:
+
+ Crc32.c
+
+Abstract:
+
+ CalculateCrc32 Boot Services as defined in DXE CIS.
+
+ This Boot Services is in the Runtime Driver because this service is
+ also required by SetVirtualAddressMap() when the EFI System Table and
+ EFI Runtime Services Table are converted from physical address to
+ virtual addresses. This requires that the 32-bit CRC be recomputed.
+
+Revision History:
+
+--*/
+
+//
+// The package level header files this module uses
+//
+#include <PiDxe.h>
+
+UINT32 mCrcTable[256];
+
+EFI_STATUS
+EFIAPI
+RuntimeDriverCalculateCrc32 (
+ IN VOID *Data,
+ IN UINTN DataSize,
+ OUT UINT32 *CrcOut
+ )
+/*++
+
+Routine Description:
+
+ Calculate CRC32 for target data
+
+Arguments:
+
+ Data - The target data.
+ DataSize - The target data size.
+ CrcOut - The CRC32 for target data.
+
+Returns:
+
+ EFI_SUCCESS - The CRC32 for target data is calculated successfully.
+ EFI_INVALID_PARAMETER - Some parameter is not valid, so the CRC32 is not
+ calculated.
+
+--*/
+{
+ UINT32 Crc;
+ UINTN Index;
+ UINT8 *Ptr;
+
+ if (Data == NULL || DataSize == 0 || CrcOut == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ Crc = 0xffffffff;
+ for (Index = 0, Ptr = Data; Index < DataSize; Index++, Ptr++) {
+ Crc = (Crc >> 8) ^ mCrcTable[(UINT8) Crc ^ *Ptr];
+ }
+
+ *CrcOut = Crc ^ 0xffffffff;
+ return EFI_SUCCESS;
+}
+
+STATIC
+UINT32
+ReverseBits (
+ UINT32 Value
+ )
+/*++
+
+Routine Description:
+
+ Reverse bits for 32bit data.
+
+Arguments:
+
+ Value - the data to be reversed.
+
+Returns:
+
+ UINT32 data reversed.
+
+--*/
+{
+ UINTN Index;
+ UINT32 NewValue;
+
+ NewValue = 0;
+ for (Index = 0; Index < 32; Index++) {
+ if (Value & (1 << Index)) {
+ NewValue = NewValue | (1 << (31 - Index));
+ }
+ }
+
+ return NewValue;
+}
+
+VOID
+RuntimeDriverInitializeCrc32Table (
+ VOID
+ )
+/*++
+
+Routine Description:
+
+ Initialize CRC32 table.
+
+Arguments:
+
+ None.
+
+Returns:
+
+ None.
+
+--*/
+{
+ UINTN TableEntry;
+ UINTN Index;
+ UINT32 Value;
+
+ for (TableEntry = 0; TableEntry < 256; TableEntry++) {
+ Value = ReverseBits ((UINT32) TableEntry);
+ for (Index = 0; Index < 8; Index++) {
+ if (Value & 0x80000000) {
+ Value = (Value << 1) ^ 0x04c11db7;
+ } else {
+ Value = Value << 1;
+ }
+ }
+
+ mCrcTable[TableEntry] = ReverseBits (Value);
+ }
+}
|