MdePkg: Replace BSD License with BSD+Patent License

[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 - 2018, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
\r
\r
#include "BaseIoLibIntrinsicInternal.h"\r
\r
//\r
// Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.\r
//\r
\r
int            _inp (unsigned short port);\r
unsigned short _inpw (unsigned short port);\r
unsigned long  _inpd (unsigned short port);\r
int            _outp (unsigned short port, int databyte );\r
unsigned short _outpw (unsigned short port, unsigned short dataword );\r
unsigned long  _outpd (unsigned short port, unsigned long dataword );\r
void          _ReadWriteBarrier (void);\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
  @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
\r
  _ReadWriteBarrier ();\r
  Value = (UINT8)_inp ((UINT16)Port);\r
  _ReadWriteBarrier ();\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
  @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
  _ReadWriteBarrier ();\r
  (UINT8)_outp ((UINT16)Port, Value);\r
  _ReadWriteBarrier ();\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
  @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
\r
  ASSERT ((Port & 1) == 0);\r
  _ReadWriteBarrier ();\r
  Value = _inpw ((UINT16)Port);\r
  _ReadWriteBarrier ();\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
  @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
  ASSERT ((Port & 1) == 0);\r
  _ReadWriteBarrier ();\r
  _outpw ((UINT16)Port, Value);\r
  _ReadWriteBarrier ();\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
  @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
\r
  ASSERT ((Port & 3) == 0);\r
  _ReadWriteBarrier ();\r
  Value = _inpd ((UINT16)Port);\r
  _ReadWriteBarrier ();\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
  @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
  ASSERT ((Port & 3) == 0);\r
  _ReadWriteBarrier ();\r
  _outpd ((UINT16)Port, Value);\r
  _ReadWriteBarrier ();\r
  return Value;\r
}\r