1 /** @file 2 I/O Library. This file has compiler specifics for Microsft C as there is no 3 ANSI C standard for doing IO. 4 5 MSC - uses intrinsic functions and the optimize will remove the function call 6 overhead. 7 8 We don't advocate putting compiler specifics in libraries or drivers but there 9 is no other way to make this work. 10 11 Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR> 12 This program and the accompanying materials 13 are licensed and made available under the terms and conditions of the BSD License 14 which accompanies this distribution. The full text of the license may be found at 15 http://opensource.org/licenses/bsd-license.php. 16 17 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 18 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 19 20 **/ 21 22 23 24 #include "BaseIoLibIntrinsicInternal.h" 25 26 // 27 // Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics. 28 // 29 30 int _inp (unsigned short port); 31 unsigned short _inpw (unsigned short port); 32 unsigned long _inpd (unsigned short port); 33 int _outp (unsigned short port, int databyte ); 34 unsigned short _outpw (unsigned short port, unsigned short dataword ); 35 unsigned long _outpd (unsigned short port, unsigned long dataword ); 36 void _ReadWriteBarrier (void); 37 38 #pragma intrinsic(_inp) 39 #pragma intrinsic(_inpw) 40 #pragma intrinsic(_inpd) 41 #pragma intrinsic(_outp) 42 #pragma intrinsic(_outpw) 43 #pragma intrinsic(_outpd) 44 #pragma intrinsic(_ReadWriteBarrier) 45 46 // 47 // _ReadWriteBarrier() forces memory reads and writes to complete at the point 48 // in the call. This is only a hint to the compiler and does emit code. 49 // In past versions of the compiler, _ReadWriteBarrier was enforced only 50 // locally and did not affect functions up the call tree. In Visual C++ 51 // 2005, _ReadWriteBarrier is enforced all the way up the call tree. 52 // 53 54 /** 55 Reads an 8-bit I/O port. 56 57 Reads the 8-bit I/O port specified by Port. The 8-bit read value is returned. 58 This function must guarantee that all I/O read and write operations are 59 serialized. 60 61 If 8-bit I/O port operations are not supported, then ASSERT(). 62 63 @param Port The I/O port to read. 64 65 @return The value read. 66 67 **/ 68 UINT8 69 EFIAPI 70 IoRead8 ( 71 IN UINTN Port 72 ) 73 { 74 UINT8 Value; 75 76 _ReadWriteBarrier (); 77 Value = (UINT8)_inp ((UINT16)Port); 78 _ReadWriteBarrier (); 79 return Value; 80 } 81 82 /** 83 Writes an 8-bit I/O port. 84 85 Writes the 8-bit I/O port specified by Port with the value specified by Value 86 and returns Value. This function must guarantee that all I/O read and write 87 operations are serialized. 88 89 If 8-bit I/O port operations are not supported, then ASSERT(). 90 91 @param Port The I/O port to write. 92 @param Value The value to write to the I/O port. 93 94 @return The value written to the I/O port. 95 96 **/ 97 UINT8 98 EFIAPI 99 IoWrite8 ( 100 IN UINTN Port, 101 IN UINT8 Value 102 ) 103 { 104 _ReadWriteBarrier (); 105 (UINT8)_outp ((UINT16)Port, Value); 106 _ReadWriteBarrier (); 107 return Value; 108 } 109 110 /** 111 Reads a 16-bit I/O port. 112 113 Reads the 16-bit I/O port specified by Port. The 16-bit read value is returned. 114 This function must guarantee that all I/O read and write operations are 115 serialized. 116 117 If 16-bit I/O port operations are not supported, then ASSERT(). 118 If Port is not aligned on a 16-bit boundary, then ASSERT(). 119 120 @param Port The I/O port to read. 121 122 @return The value read. 123 124 **/ 125 UINT16 126 EFIAPI 127 IoRead16 ( 128 IN UINTN Port 129 ) 130 { 131 UINT16 Value; 132 133 ASSERT ((Port & 1) == 0); 134 _ReadWriteBarrier (); 135 Value = _inpw ((UINT16)Port); 136 _ReadWriteBarrier (); 137 return Value; 138 } 139 140 /** 141 Writes a 16-bit I/O port. 142 143 Writes the 16-bit I/O port specified by Port with the value specified by Value 144 and returns Value. This function must guarantee that all I/O read and write 145 operations are serialized. 146 147 If 16-bit I/O port operations are not supported, then ASSERT(). 148 If Port is not aligned on a 16-bit boundary, then ASSERT(). 149 150 @param Port The I/O port to write. 151 @param Value The value to write to the I/O port. 152 153 @return The value written to the I/O port. 154 155 **/ 156 UINT16 157 EFIAPI 158 IoWrite16 ( 159 IN UINTN Port, 160 IN UINT16 Value 161 ) 162 { 163 ASSERT ((Port & 1) == 0); 164 _ReadWriteBarrier (); 165 _outpw ((UINT16)Port, Value); 166 _ReadWriteBarrier (); 167 return Value; 168 } 169 170 /** 171 Reads a 32-bit I/O port. 172 173 Reads the 32-bit I/O port specified by Port. The 32-bit read value is returned. 174 This function must guarantee that all I/O read and write operations are 175 serialized. 176 177 If 32-bit I/O port operations are not supported, then ASSERT(). 178 If Port is not aligned on a 32-bit boundary, then ASSERT(). 179 180 @param Port The I/O port to read. 181 182 @return The value read. 183 184 **/ 185 UINT32 186 EFIAPI 187 IoRead32 ( 188 IN UINTN Port 189 ) 190 { 191 UINT32 Value; 192 193 ASSERT ((Port & 3) == 0); 194 _ReadWriteBarrier (); 195 Value = _inpd ((UINT16)Port); 196 _ReadWriteBarrier (); 197 return Value; 198 } 199 200 /** 201 Writes a 32-bit I/O port. 202 203 Writes the 32-bit I/O port specified by Port with the value specified by Value 204 and returns Value. This function must guarantee that all I/O read and write 205 operations are serialized. 206 207 If 32-bit I/O port operations are not supported, then ASSERT(). 208 If Port is not aligned on a 32-bit boundary, then ASSERT(). 209 210 @param Port The I/O port to write. 211 @param Value The value to write to the I/O port. 212 213 @return The value written to the I/O port. 214 215 **/ 216 UINT32 217 EFIAPI 218 IoWrite32 ( 219 IN UINTN Port, 220 IN UINT32 Value 221 ) 222 { 223 ASSERT ((Port & 3) == 0); 224 _ReadWriteBarrier (); 225 _outpd ((UINT16)Port, Value); 226 _ReadWriteBarrier (); 227 return Value; 228 } 229
