IntelFrameworkModulePkg: Replace BSD License with BSD+Patent License

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

/** @file\r
  This code fills in BDA (0x400) and EBDA (pointed to by 0x4xx)\r
  information. There is support for doing initializeation before\r
  Legacy16 is loaded and before a legacy boot is attempted.\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
  Fill in the standard BDA and EBDA 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
LegacyBiosInitBda (\r
  IN  LEGACY_BIOS_INSTANCE    *Private\r
  )\r
{\r
  BDA_STRUC *Bda;\r
  UINT8     *Ebda;\r
\r
  Bda   = (BDA_STRUC *) ((UINTN) 0x400);\r
  Ebda  = (UINT8 *) ((UINTN) 0x9fc00);\r
\r
  ACCESS_PAGE0_CODE (\r
    ZeroMem (Bda, 0x100);\r
    //\r
    // 640k-1k for EBDA\r
    //\r
    Bda->MemSize        = 0x27f;\r
    Bda->KeyHead        = 0x1e;\r
    Bda->KeyTail        = 0x1e;\r
    Bda->FloppyData     = 0x00;\r
    Bda->FloppyTimeout  = 0xff;\r
\r
    Bda->KeyStart       = 0x001E;\r
    Bda->KeyEnd         = 0x003E;\r
    Bda->KeyboardStatus = 0x10;\r
    Bda->Ebda           = 0x9fc0;\r
\r
    //\r
    // Move LPT time out here and zero out LPT4 since some SCSI OPROMS\r
    // use this as scratch pad (LPT4 is Reserved)\r
    //\r
    Bda->Lpt1_2Timeout  = 0x1414;\r
    Bda->Lpt3_4Timeout  = 0x1400;\r
\r
  );\r
\r
  ZeroMem (Ebda, 0x400);\r
  *Ebda = 0x01;\r
\r
  return EFI_SUCCESS;\r
}\r