1 /** @file 2 Functions for access I2C MMIO register. 3 4 Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR> 5 This program and the accompanying materials 6 are licensed and made available under the terms and conditions of the BSD License 7 which accompanies this distribution. The full text of the license may be found at 8 http://opensource.org/licenses/bsd-license.php. 9 10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 12 13 **/ 14 15 #include <PiPei.h> 16 #include <Library/DebugLib.h> 17 #include <Library/PeiServicesTablePointerLib.h> 18 19 /** 20 Reads an 8-bit MMIO register. 21 22 Reads the 8-bit MMIO register specified by Address. The 8-bit read value is 23 returned. This function must guarantee that all MMIO read and write 24 operations are serialized. 25 26 If 8-bit MMIO register operations are not supported, then ASSERT(). 27 28 @param Address The MMIO register to read. 29 30 @return The value read. 31 32 **/ 33 UINT8 34 EFIAPI 35 I2CLibPeiMmioRead8 ( 36 IN UINTN Address 37 ) 38 { 39 UINT8 Value; 40 41 Value = *(volatile UINT8*)Address; 42 return Value; 43 } 44 45 /** 46 Reads a 16-bit MMIO register. 47 48 Reads the 16-bit MMIO register specified by Address. The 16-bit read value is 49 returned. This function must guarantee that all MMIO read and write 50 operations are serialized. 51 52 If 16-bit MMIO register operations are not supported, then ASSERT(). 53 If Address is not aligned on a 16-bit boundary, then ASSERT(). 54 55 @param Address The MMIO register to read. 56 57 @return The value read. 58 59 **/ 60 UINT16 61 EFIAPI 62 I2CLibPeiMmioRead16 ( 63 IN UINTN Address 64 ) 65 { 66 UINT16 Value; 67 68 ASSERT ((Address & 1) == 0); 69 Value = *(volatile UINT16*)Address; 70 return Value; 71 } 72 73 /** 74 Writes a 16-bit MMIO register. 75 76 Writes the 16-bit MMIO register specified by Address with the value specified 77 by Value and returns Value. This function must guarantee that all MMIO read 78 and write operations are serialized. 79 80 If 16-bit MMIO register operations are not supported, then ASSERT(). 81 If Address is not aligned on a 16-bit boundary, then ASSERT(). 82 83 @param Address The MMIO register to write. 84 @param Value The value to write to the MMIO register. 85 86 @return Value. 87 88 **/ 89 UINT16 90 EFIAPI 91 I2CLibPeiMmioWrite16 ( 92 IN UINTN Address, 93 IN UINT16 Value 94 ) 95 { 96 ASSERT ((Address & 1) == 0); 97 *(volatile UINT16*)Address = Value; 98 return Value; 99 } 100 101 /** 102 Reads a 32-bit MMIO register. 103 104 Reads the 32-bit MMIO register specified by Address. The 32-bit read value is 105 returned. This function must guarantee that all MMIO read and write 106 operations are serialized. 107 108 If 32-bit MMIO register operations are not supported, then ASSERT(). 109 If Address is not aligned on a 32-bit boundary, then ASSERT(). 110 111 @param Address The MMIO register to read. 112 113 @return The value read. 114 115 **/ 116 UINT32 117 EFIAPI 118 I2CLibPeiMmioRead32 ( 119 IN UINTN Address 120 ) 121 { 122 UINT32 Value; 123 124 ASSERT ((Address & 3) == 0); 125 Value = *(volatile UINT32*)Address; 126 127 return Value; 128 } 129 130 /** 131 Writes a 32-bit MMIO register. 132 133 Writes the 32-bit MMIO register specified by Address with the value specified 134 by Value and returns Value. This function must guarantee that all MMIO read 135 and write operations are serialized. 136 137 If 32-bit MMIO register operations are not supported, then ASSERT(). 138 If Address is not aligned on a 32-bit boundary, then ASSERT(). 139 140 @param Address The MMIO register to write. 141 @param Value The value to write to the MMIO register. 142 143 @return Value. 144 145 **/ 146 UINT32 147 EFIAPI 148 I2CLibPeiMmioWrite32 ( 149 IN UINTN Address, 150 IN UINT32 Value 151 ) 152 { 153 ASSERT ((Address & 3) == 0); 154 *(volatile UINT32*)Address = Value; 155 return Value; 156 } 157 158 /** 159 OR a 32-bit MMIO register. 160 161 OR the 32-bit MMIO register specified by Address with the value specified 162 by Value and returns Value. This function must guarantee that all MMIO read 163 and write operations are serialized. 164 165 If 32-bit MMIO register operations are not supported, then ASSERT(). 166 If Address is not aligned on a 32-bit boundary, then ASSERT(). 167 168 @param Address The MMIO register to write OR. 169 @param Value The value to OR to the MMIO register. 170 171 @return Value. 172 173 **/ 174 UINT32 175 EFIAPI 176 I2CLibPeiMmioOr32 ( 177 IN UINTN Address, 178 IN UINT32 OrData 179 ) 180 { 181 return I2CLibPeiMmioWrite32 (Address, I2CLibPeiMmioRead32(Address) | OrData); 182 } 183 184 185
