IntelFrameworkModulePkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / IntelFrameworkModulePkg / Csm / LegacyBiosDxe / LegacyCmos.c

/** @file\r
  This code fills in standard CMOS values and updates the standard CMOS\r
  checksum. The Legacy16 code or LegacyBiosPlatform.c is responsible for\r
  non-standard CMOS locations and non-standard checksums.\r
\r
Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>\r
\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "LegacyBiosInterface.h"\r
\r
/**\r
  Read CMOS register through index/data port.\r
\r
  @param[in]  Index   The index of the CMOS register to read.\r
\r
  @return  The data value from the CMOS register specified by Index.\r
\r
**/\r
UINT8\r
LegacyReadStandardCmos (\r
  IN UINT8  Index\r
  )\r
{\r
  IoWrite8 (PORT_70, Index);\r
  return IoRead8 (PORT_71);\r
}\r
\r
/**\r
  Write CMOS register through index/data port.\r
\r
  @param[in]  Index  The index of the CMOS register to write.\r
  @param[in]  Value  The value of CMOS register to write.\r
\r
  @return  The value written to the CMOS register specified by Index.\r
\r
**/\r
UINT8\r
LegacyWriteStandardCmos (\r
  IN UINT8  Index,\r
  IN UINT8  Value\r
  )\r
{\r
  IoWrite8 (PORT_70, Index);\r
  return IoWrite8 (PORT_71, Value);\r
}\r
\r
/**\r
  Calculate the new standard CMOS checksum and write it.\r
\r
  @param  Private      Legacy BIOS Instance data\r
\r
  @retval EFI_SUCCESS  Calculate 16-bit checksum successfully\r
\r
**/\r
EFI_STATUS\r
LegacyCalculateWriteStandardCmosChecksum (\r
  VOID\r
  )\r
{\r
  UINT8   Register;\r
  UINT16  Checksum;\r
\r
  for (Checksum = 0, Register = 0x10; Register < 0x2e; Register++) {\r
    Checksum = (UINT16)(Checksum + LegacyReadStandardCmos (Register));\r
  }\r
  LegacyWriteStandardCmos (CMOS_2E, (UINT8)(Checksum >> 8));\r
  LegacyWriteStandardCmos (CMOS_2F, (UINT8)(Checksum & 0xff));\r
  return EFI_SUCCESS;\r
}\r
\r
\r
/**\r
  Fill in the standard CMOS stuff before Legacy16 load\r
\r
  @param  Private      Legacy BIOS Instance data\r
\r
  @retval EFI_SUCCESS  It should always work.\r
\r
**/\r
EFI_STATUS\r
LegacyBiosInitCmos (\r
  IN  LEGACY_BIOS_INSTANCE    *Private\r
  )\r
{\r
  UINT32  Size;\r
\r
  //\r
  //  Clear all errors except RTC lost power\r
  //\r
  LegacyWriteStandardCmos (CMOS_0E, (UINT8)(LegacyReadStandardCmos (CMOS_0E) & BIT7));\r
\r
  //\r
  // Update CMOS locations 15,16,17,18,30,31 and 32\r
  // CMOS 16,15 = 640Kb = 0x280\r
  // CMOS 18,17 = 31,30 = 15Mb max in 1Kb increments =0x3C00 max\r
  // CMOS 32 = 0x20\r
  //\r
  LegacyWriteStandardCmos (CMOS_15, 0x80);\r
  LegacyWriteStandardCmos (CMOS_16, 0x02);\r
\r
  Size = 15 * SIZE_1MB;\r
  if (Private->IntThunk->EfiToLegacy16InitTable.OsMemoryAbove1Mb < (15 * SIZE_1MB)) {\r
    Size  = Private->IntThunk->EfiToLegacy16InitTable.OsMemoryAbove1Mb >> 10;\r
  }\r
\r
  LegacyWriteStandardCmos (CMOS_17, (UINT8)(Size & 0xFF));\r
  LegacyWriteStandardCmos (CMOS_30, (UINT8)(Size & 0xFF));\r
  LegacyWriteStandardCmos (CMOS_18, (UINT8)(Size >> 8));\r
  LegacyWriteStandardCmos (CMOS_31, (UINT8)(Size >> 8));\r
\r
  LegacyCalculateWriteStandardCmosChecksum ();\r
\r
  return EFI_SUCCESS;\r
}\r