alder_lake_bios/Insyde/InsydeModulePkg/Csm/LegacyBiosDxe/LegacyCmos.c

127 lines
3.2 KiB
C

/** @file
This code fills in standard CMOS values and updates the standard CMOS
checksum. The Legacy16 code or LegacyBiosPlatform.c is responsible for
non-standard CMOS locations and non-standard checksums.
;******************************************************************************
;* Copyright (c) 2012, Insyde Software Corporation. All Rights Reserved.
;*
;* You may not reproduce, distribute, publish, display, perform, modify, adapt,
;* transmit, broadcast, present, recite, release, license or otherwise exploit
;* any part of this publication in any form, by any means, without the prior
;* written permission of Insyde Software Corporation.
;*
;******************************************************************************
*/
#include "LegacyBiosInterface.h"
/**
Read CMOS register through index/data port.
@param[in] Index The index of the CMOS register to read.
@return The data value from the CMOS register specified by Index.
**/
UINT8
LegacyReadStandardCmos (
IN UINT8 Index
)
{
return ReadCmos8 (Index);
}
/**
Write CMOS register through index/data port.
@param[in] Index The index of the CMOS register to write.
@param[in] Value The value of CMOS register to write.
@return The value written to the CMOS register specified by Index.
**/
VOID
LegacyWriteStandardCmos (
IN UINT8 Index,
IN UINT8 Value
)
{
WriteCmos8 (Index, Value);
}
/**
Calculate the new standard CMOS checksum and write it.
@param Private Legacy BIOS Instance data
@retval EFI_SUCCESS Calculate 16-bit checksum successfully
**/
EFI_STATUS
LegacyCalculateWriteStandardCmosChecksum (
VOID
)
{
UINT8 Register;
UINT16 Checksum;
for (Checksum = 0, Register = 0x10; Register < 0x2e; Register++) {
Checksum = (UINT16)(Checksum + LegacyReadStandardCmos (Register));
}
LegacyWriteStandardCmos (CMOS_2E, (UINT8)(Checksum >> 8));
LegacyWriteStandardCmos (CMOS_2F, (UINT8)(Checksum & 0xff));
return EFI_SUCCESS;
}
/**
Fill in the standard CMOS stuff before Legacy16 load
@param Private Legacy BIOS Instance data
@retval EFI_SUCCESS It should always work.
**/
EFI_STATUS
LegacyBiosInitCmos (
IN LEGACY_BIOS_INSTANCE *Private
)
{
UINT32 Size;
UINT8 Temp;
UINT8 Temp1;
//
// Clear all errors except RTC lost power
//
LegacyWriteStandardCmos (CMOS_0E, (UINT8)(LegacyReadStandardCmos (CMOS_0E) & BIT7));
//
// Update CMOS locations 15,16,17,18,30,31 and 32
// CMOS 16,15 = 640Kb = 0x280
// CMOS 18,17 = 31,30 = 15Mb max in 1Kb increments =0x3C00 max
// CMOS 32 = 0x20
//
LegacyWriteStandardCmos (CMOS_15, 0x80);
LegacyWriteStandardCmos (CMOS_16, 0x02);
Size = 63 * SIZE_1MB;
Temp = 0x00;
Temp1 = 0xFC;
if (Private->IntThunk->EfiToLegacy16InitTable.OsMemoryAbove1Mb < (63 * SIZE_1MB)) {
Size = Private->IntThunk->EfiToLegacy16InitTable.OsMemoryAbove1Mb >> 10;
Temp = (UINT8) (Size & 0xFF);
Temp1 = (UINT8) (Size >> 8);
}
LegacyWriteStandardCmos (CMOS_17, Temp);
LegacyWriteStandardCmos (CMOS_30, Temp);
LegacyWriteStandardCmos (CMOS_18, Temp1);
LegacyWriteStandardCmos (CMOS_31, Temp1);
LegacyCalculateWriteStandardCmosChecksum ();
return EFI_SUCCESS;
}