MdePkg: Probe Cc guest in BaseIoLibIntrinsicSev

[mirror_edk2.git] / MdePkg / Library / BaseIoLibIntrinsic / IoLibMsc.c

/** @file\r
  I/O Library. This file has compiler specifics for Microsft C as there is no\r
  ANSI C standard for doing IO.\r
\r
  MSC - uses intrinsic functions and the optimize will remove the function call\r
  overhead.\r
\r
  We don't advocate putting compiler specifics in libraries or drivers but there\r
  is no other way to make this work.\r
\r
  Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "BaseIoLibIntrinsicInternal.h"\r
#include "IoLibTdx.h"\r
\r
//\r
// Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.\r
//\r
\r
int\r
_inp (\r
  unsigned short  port\r
  );\r
\r
unsigned short\r
_inpw (\r
  unsigned short  port\r
  );\r
\r
unsigned long\r
_inpd (\r
  unsigned short  port\r
  );\r
\r
int\r
_outp (\r
  unsigned short  port,\r
  int             databyte\r
  );\r
\r
unsigned short\r
_outpw (\r
  unsigned short  port,\r
  unsigned short  dataword\r
  );\r
\r
unsigned long\r
_outpd (\r
  unsigned short  port,\r
  unsigned long   dataword\r
  );\r
\r
void\r
_ReadWriteBarrier (\r
  void\r
  );\r
\r
#pragma intrinsic(_inp)\r
#pragma intrinsic(_inpw)\r
#pragma intrinsic(_inpd)\r
#pragma intrinsic(_outp)\r
#pragma intrinsic(_outpw)\r
#pragma intrinsic(_outpd)\r
#pragma intrinsic(_ReadWriteBarrier)\r
\r
//\r
// _ReadWriteBarrier() forces memory reads and writes to complete at the point\r
// in the call. This is only a hint to the compiler and does emit code.\r
// In past versions of the compiler, _ReadWriteBarrier was enforced only\r
// locally and did not affect functions up the call tree. In Visual C++\r
// 2005, _ReadWriteBarrier is enforced all the way up the call tree.\r
//\r
\r
/**\r
  Reads an 8-bit I/O port.\r
\r
  Reads the 8-bit I/O port specified by Port. The 8-bit read value is returned.\r
  This function must guarantee that all I/O read and write operations are\r
  serialized.\r
\r
  If 8-bit I/O port operations are not supported, then ASSERT().\r
\r
  For Td guest TDVMCALL_IO is invoked to read I/O port.\r
\r
  @param  Port  The I/O port to read.\r
\r
  @return The value read.\r
\r
**/\r
UINT8\r
EFIAPI\r
IoRead8 (\r
  IN      UINTN  Port\r
  )\r
{\r
  UINT8    Value;\r
  BOOLEAN  Flag;\r
\r
  Flag = FilterBeforeIoRead (FilterWidth8, Port, &Value);\r
  if (Flag) {\r
    if (IsTdxGuest ()) {\r
      Value = TdIoRead8 (Port);\r
    } else {\r
      _ReadWriteBarrier ();\r
      Value = (UINT8)_inp ((UINT16)Port);\r
      _ReadWriteBarrier ();\r
    }\r
  }\r
\r
  FilterAfterIoRead (FilterWidth8, Port, &Value);\r
\r
  return Value;\r
}\r
\r
/**\r
  Writes an 8-bit I/O port.\r
\r
  Writes the 8-bit I/O port specified by Port with the value specified by Value\r
  and returns Value. This function must guarantee that all I/O read and write\r
  operations are serialized.\r
\r
  If 8-bit I/O port operations are not supported, then ASSERT().\r
\r
  For Td guest TDVMCALL_IO is invoked to write I/O port.\r
\r
  @param  Port  The I/O port to write.\r
  @param  Value The value to write to the I/O port.\r
\r
  @return The value written to the I/O port.\r
\r
**/\r
UINT8\r
EFIAPI\r
IoWrite8 (\r
  IN      UINTN  Port,\r
  IN      UINT8  Value\r
  )\r
{\r
  BOOLEAN  Flag;\r
\r
  Flag = FilterBeforeIoWrite (FilterWidth8, Port, &Value);\r
  if (Flag) {\r
    if (IsTdxGuest ()) {\r
      TdIoWrite8 (Port, Value);\r
    } else {\r
      _ReadWriteBarrier ();\r
      (UINT8)_outp ((UINT16)Port, Value);\r
      _ReadWriteBarrier ();\r
    }\r
  }\r
\r
  FilterAfterIoWrite (FilterWidth8, Port, &Value);\r
\r
  return Value;\r
}\r
\r
/**\r
  Reads a 16-bit I/O port.\r
\r
  Reads the 16-bit I/O port specified by Port. The 16-bit read value is returned.\r
  This function must guarantee that all I/O read and write operations are\r
  serialized.\r
\r
  If 16-bit I/O port operations are not supported, then ASSERT().\r
  If Port is not aligned on a 16-bit boundary, then ASSERT().\r
\r
  For Td guest TDVMCALL_IO is invoked to read I/O port.\r
\r
  @param  Port  The I/O port to read.\r
\r
  @return The value read.\r
\r
**/\r
UINT16\r
EFIAPI\r
IoRead16 (\r
  IN      UINTN  Port\r
  )\r
{\r
  UINT16   Value;\r
  BOOLEAN  Flag;\r
\r
  ASSERT ((Port & 1) == 0);\r
\r
  Flag = FilterBeforeIoRead (FilterWidth16, Port, &Value);\r
  if (Flag) {\r
    if (IsTdxGuest ()) {\r
      Value = TdIoRead16 (Port);\r
    } else {\r
      _ReadWriteBarrier ();\r
      Value = _inpw ((UINT16)Port);\r
      _ReadWriteBarrier ();\r
    }\r
  }\r
\r
  FilterBeforeIoRead (FilterWidth16, Port, &Value);\r
\r
  return Value;\r
}\r
\r
/**\r
  Writes a 16-bit I/O port.\r
\r
  Writes the 16-bit I/O port specified by Port with the value specified by Value\r
  and returns Value. This function must guarantee that all I/O read and write\r
  operations are serialized.\r
\r
  If 16-bit I/O port operations are not supported, then ASSERT().\r
  If Port is not aligned on a 16-bit boundary, then ASSERT().\r
\r
  For Td guest TDVMCALL_IO is invoked to write I/O port.\r
\r
  @param  Port  The I/O port to write.\r
  @param  Value The value to write to the I/O port.\r
\r
  @return The value written to the I/O port.\r
\r
**/\r
UINT16\r
EFIAPI\r
IoWrite16 (\r
  IN      UINTN   Port,\r
  IN      UINT16  Value\r
  )\r
{\r
  BOOLEAN  Flag;\r
\r
  ASSERT ((Port & 1) == 0);\r
\r
  Flag = FilterBeforeIoWrite (FilterWidth16, Port, &Value);\r
  if (Flag) {\r
    if (IsTdxGuest ()) {\r
      TdIoWrite16 (Port, Value);\r
    } else {\r
      _ReadWriteBarrier ();\r
      _outpw ((UINT16)Port, Value);\r
      _ReadWriteBarrier ();\r
    }\r
  }\r
\r
  FilterAfterIoWrite (FilterWidth16, Port, &Value);\r
\r
  return Value;\r
}\r
\r
/**\r
  Reads a 32-bit I/O port.\r
\r
  Reads the 32-bit I/O port specified by Port. The 32-bit read value is returned.\r
  This function must guarantee that all I/O read and write operations are\r
  serialized.\r
\r
  If 32-bit I/O port operations are not supported, then ASSERT().\r
  If Port is not aligned on a 32-bit boundary, then ASSERT().\r
\r
  For Td guest TDVMCALL_IO is invoked to read I/O port.\r
\r
  @param  Port  The I/O port to read.\r
\r
  @return The value read.\r
\r
**/\r
UINT32\r
EFIAPI\r
IoRead32 (\r
  IN      UINTN  Port\r
  )\r
{\r
  UINT32   Value;\r
  BOOLEAN  Flag;\r
\r
  ASSERT ((Port & 3) == 0);\r
\r
  Flag = FilterBeforeIoRead (FilterWidth32, Port, &Value);\r
  if (Flag) {\r
    if (IsTdxGuest ()) {\r
      Value = TdIoRead32 (Port);\r
    } else {\r
      _ReadWriteBarrier ();\r
      Value = _inpd ((UINT16)Port);\r
      _ReadWriteBarrier ();\r
    }\r
  }\r
\r
  FilterAfterIoRead (FilterWidth32, Port, &Value);\r
\r
  return Value;\r
}\r
\r
/**\r
  Writes a 32-bit I/O port.\r
\r
  Writes the 32-bit I/O port specified by Port with the value specified by Value\r
  and returns Value. This function must guarantee that all I/O read and write\r
  operations are serialized.\r
\r
  If 32-bit I/O port operations are not supported, then ASSERT().\r
  If Port is not aligned on a 32-bit boundary, then ASSERT().\r
\r
  For Td guest TDVMCALL_IO is invoked to write I/O port.\r
\r
  @param  Port  The I/O port to write.\r
  @param  Value The value to write to the I/O port.\r
\r
  @return The value written to the I/O port.\r
\r
**/\r
UINT32\r
EFIAPI\r
IoWrite32 (\r
  IN      UINTN   Port,\r
  IN      UINT32  Value\r
  )\r
{\r
  BOOLEAN  Flag;\r
\r
  ASSERT ((Port & 3) == 0);\r
\r
  Flag = FilterBeforeIoWrite (FilterWidth32, Port, &Value);\r
  if (Flag) {\r
    if (IsTdxGuest ()) {\r
      TdIoWrite32 (Port, Value);\r
    } else {\r
      _ReadWriteBarrier ();\r
      _outpd ((UINT16)Port, Value);\r
      _ReadWriteBarrier ();\r
    }\r
  }\r
\r
  FilterAfterIoWrite (FilterWidth32, Port, &Value);\r
\r
  return Value;\r
}\r