Vlv2TbltDevicePkg/Library/I2CLibPei/I2CIoLibPei.c

   1 /** @file
   2   Functions for access I2C MMIO register.
   3
   4   Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include <PiPei.h>
  10 #include <Library/DebugLib.h>
  11 #include <Library/PeiServicesTablePointerLib.h>
  12
  13 /**
  14   Reads an 8-bit MMIO register.
  15
  16   Reads the 8-bit MMIO register specified by Address. The 8-bit read value is
  17   returned. This function must guarantee that all MMIO read and write
  18   operations are serialized.
  19
  20   If 8-bit MMIO register operations are not supported, then ASSERT().
  21
  22   @param  Address The MMIO register to read.
  23
  24   @return The value read.
  25
  26 **/
  27 UINT8
  28 EFIAPI
  29 I2CLibPeiMmioRead8 (
  30   IN UINTN Address
  31   )
  32 {
  33   UINT8 Value;
  34
  35   Value = *(volatile UINT8*)Address;
  36   return Value;
  37 }
  38
  39 /**
  40   Reads a 16-bit MMIO register.
  41
  42   Reads the 16-bit MMIO register specified by Address. The 16-bit read value is
  43   returned. This function must guarantee that all MMIO read and write
  44   operations are serialized.
  45
  46   If 16-bit MMIO register operations are not supported, then ASSERT().
  47   If Address is not aligned on a 16-bit boundary, then ASSERT().
  48
  49   @param  Address The MMIO register to read.
  50
  51   @return The value read.
  52
  53 **/
  54 UINT16
  55 EFIAPI
  56 I2CLibPeiMmioRead16 (
  57   IN UINTN  Address
  58   )
  59 {
  60   UINT16 Value;
  61
  62   ASSERT ((Address & 1) == 0);
  63   Value = *(volatile UINT16*)Address;
  64   return Value;
  65 }
  66
  67 /**
  68   Writes a 16-bit MMIO register.
  69
  70   Writes the 16-bit MMIO register specified by Address with the value specified
  71   by Value and returns Value. This function must guarantee that all MMIO read
  72   and write operations are serialized.
  73
  74   If 16-bit MMIO register operations are not supported, then ASSERT().
  75   If Address is not aligned on a 16-bit boundary, then ASSERT().
  76
  77   @param  Address The MMIO register to write.
  78   @param  Value   The value to write to the MMIO register.
  79
  80   @return Value.
  81
  82 **/
  83 UINT16
  84 EFIAPI
  85 I2CLibPeiMmioWrite16 (
  86   IN  UINTN   Address,
  87   IN  UINT16  Value
  88   )
  89 {
  90   ASSERT ((Address & 1) == 0);
  91   *(volatile UINT16*)Address = Value;
  92   return Value;
  93 }
  94
  95 /**
  96   Reads a 32-bit MMIO register.
  97
  98   Reads the 32-bit MMIO register specified by Address. The 32-bit read value is
  99   returned. This function must guarantee that all MMIO read and write
 100   operations are serialized.
 101
 102   If 32-bit MMIO register operations are not supported, then ASSERT().
 103   If Address is not aligned on a 32-bit boundary, then ASSERT().
 104
 105   @param  Address The MMIO register to read.
 106
 107   @return The value read.
 108
 109 **/
 110 UINT32
 111 EFIAPI
 112 I2CLibPeiMmioRead32 (
 113   IN UINTN Address
 114   )
 115 {
 116   UINT32  Value;
 117
 118   ASSERT ((Address & 3) == 0);
 119   Value = *(volatile UINT32*)Address;
 120
 121   return Value;
 122 }
 123
 124 /**
 125   Writes a 32-bit MMIO register.
 126
 127   Writes the 32-bit MMIO register specified by Address with the value specified
 128   by Value and returns Value. This function must guarantee that all MMIO read
 129   and write operations are serialized.
 130
 131   If 32-bit MMIO register operations are not supported, then ASSERT().
 132   If Address is not aligned on a 32-bit boundary, then ASSERT().
 133
 134   @param  Address The MMIO register to write.
 135   @param  Value   The value to write to the MMIO register.
 136
 137   @return Value.
 138
 139 **/
 140 UINT32
 141 EFIAPI
 142 I2CLibPeiMmioWrite32 (
 143   IN      UINTN                     Address,
 144   IN      UINT32                    Value
 145   )
 146 {
 147   ASSERT ((Address & 3) == 0);
 148   *(volatile UINT32*)Address = Value;
 149   return Value;
 150 }
 151
 152 /**
 153   OR a 32-bit MMIO register.
 154
 155   OR the 32-bit MMIO register specified by Address with the value specified
 156   by Value and returns Value. This function must guarantee that all MMIO read
 157   and write operations are serialized.
 158
 159   If 32-bit MMIO register operations are not supported, then ASSERT().
 160   If Address is not aligned on a 32-bit boundary, then ASSERT().
 161
 162   @param  Address The MMIO register to write OR.
 163   @param  Value   The value to OR to the MMIO register.
 164
 165   @return Value.
 166
 167 **/
 168 UINT32
 169 EFIAPI
 170 I2CLibPeiMmioOr32 (
 171   IN      UINTN                     Address,
 172   IN      UINT32                    OrData
 173   )
 174 {
 175   return I2CLibPeiMmioWrite32 (Address, I2CLibPeiMmioRead32(Address) | OrData);
 176 }
 177
 178