MdePkg/Library/BaseIoLibIntrinsic/IoLibIcc.c

   1 /** @file
   2   I/O Library. This file has compiler specifics for ICC as there
   3   is no ANSI C standard for doing IO.
   4
   5   Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
   6   SPDX-License-Identifier: BSD-2-Clause-Patent
   7
   8 **/
   9
  10 #include "BaseIoLibIntrinsicInternal.h"
  11
  12 /**
  13   Reads an 8-bit I/O port.
  14
  15   Reads the 8-bit I/O port specified by Port. The 8-bit read value is returned.
  16   This function must guarantee that all I/O read and write operations are
  17   serialized.
  18
  19   If 8-bit I/O port operations are not supported, then ASSERT().
  20
  21   @param  Port  The I/O port to read.
  22
  23   @return The value read.
  24
  25 **/
  26 UINT8
  27 EFIAPI
  28 IoRead8 (
  29   IN      UINTN                     Port
  30   )
  31 {
  32   UINT8   Data;
  33
  34   __asm {
  35     mov dx, word ptr [Port]
  36     in  al, dx
  37
  38     mov Data, al
  39   }
  40   return Data;
  41 }
  42
  43 /**
  44   Writes an 8-bit I/O port.
  45
  46   Writes the 8-bit I/O port specified by Port with the value specified by Value
  47   and returns Value. This function must guarantee that all I/O read and write
  48   operations are serialized.
  49
  50   If 8-bit I/O port operations are not supported, then ASSERT().
  51
  52   @param  Port  The I/O port to write.
  53   @param  Value The value to write to the I/O port.
  54
  55   @return The value written the I/O port.
  56
  57 **/
  58 UINT8
  59 EFIAPI
  60 IoWrite8 (
  61   IN      UINTN                     Port,
  62   IN      UINT8                     Value
  63   )
  64 {
  65   __asm {
  66     mov al, byte ptr [Value]
  67     mov dx, word ptr [Port]
  68     out dx, al
  69   }
  70   return Value;
  71 }
  72
  73 /**
  74   Reads a 16-bit I/O port.
  75
  76   Reads the 16-bit I/O port specified by Port. The 16-bit read value is returned.
  77   This function must guarantee that all I/O read and write operations are
  78   serialized.
  79
  80   If 16-bit I/O port operations are not supported, then ASSERT().
  81   If Port is not aligned on a 16-bit boundary, then ASSERT().
  82
  83   @param  Port  The I/O port to read.
  84
  85   @return The value read.
  86
  87 **/
  88 UINT16
  89 EFIAPI
  90 IoRead16 (
  91   IN      UINTN                     Port
  92   )
  93 {
  94   UINT16  Data;
  95
  96   ASSERT ((Port & 1) == 0);
  97
  98   __asm {
  99     mov dx, word ptr [Port]
 100     in  ax, dx
 101     mov word ptr [Data], ax
 102   }
 103
 104   return Data;
 105 }
 106
 107 /**
 108   Writes a 16-bit I/O port.
 109
 110   Writes the 16-bit I/O port specified by Port with the value specified by Value
 111   and returns Value. This function must guarantee that all I/O read and write
 112   operations are serialized.
 113
 114   If 16-bit I/O port operations are not supported, then ASSERT().
 115   If Port is not aligned on a 16-bit boundary, then ASSERT().
 116
 117   @param  Port  The I/O port to write.
 118   @param  Value The value to write to the I/O port.
 119
 120   @return The value written the I/O port.
 121
 122 **/
 123 UINT16
 124 EFIAPI
 125 IoWrite16 (
 126   IN      UINTN                     Port,
 127   IN      UINT16                    Value
 128   )
 129 {
 130   ASSERT ((Port & 1) == 0);
 131
 132   __asm {
 133     mov ax, word ptr [Value]
 134     mov dx, word ptr [Port]
 135     out dx, ax
 136   }
 137
 138   return Value;
 139 }
 140
 141 /**
 142   Reads a 32-bit I/O port.
 143
 144   Reads the 32-bit I/O port specified by Port. The 32-bit read value is returned.
 145   This function must guarantee that all I/O read and write operations are
 146   serialized.
 147
 148   If 32-bit I/O port operations are not supported, then ASSERT().
 149   If Port is not aligned on a 32-bit boundary, then ASSERT().
 150
 151   @param  Port  The I/O port to read.
 152
 153   @return The value read.
 154
 155 **/
 156 UINT32
 157 EFIAPI
 158 IoRead32 (
 159   IN      UINTN                     Port
 160   )
 161 {
 162   UINT32 Data;
 163
 164   ASSERT ((Port & 3) == 0);
 165
 166   __asm {
 167     mov dx, word ptr [Port]
 168     in  eax, dx
 169     mov dword ptr [Data], eax
 170   }
 171
 172   return Data;
 173 }
 174
 175 /**
 176   Writes a 32-bit I/O port.
 177
 178   Writes the 32-bit I/O port specified by Port with the value specified by Value
 179   and returns Value. This function must guarantee that all I/O read and write
 180   operations are serialized.
 181
 182   If 32-bit I/O port operations are not supported, then ASSERT().
 183   If Port is not aligned on a 32-bit boundary, then ASSERT().
 184
 185   @param  Port  The I/O port to write.
 186   @param  Value The value to write to the I/O port.
 187
 188   @return The value written the I/O port.
 189
 190 **/
 191 UINT32
 192 EFIAPI
 193 IoWrite32 (
 194   IN      UINTN                     Port,
 195   IN      UINT32                    Value
 196   )
 197 {
 198   ASSERT ((Port & 3) == 0);
 199
 200   __asm {
 201     mov eax, dword ptr [Value]
 202     mov dx, word ptr [Port]
 203     out dx, eax
 204   }
 205
 206   return Value;
 207 }
 208