MdePkg/Library/PeiSmbusLib/PeiSmbusLib.c

   1 /** @file
   2 Implementation of SmBusLib class library for PEI phase.
   3
   4 Copyright (c) 2006, Intel Corporation<BR>
   5 All rights reserved. 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 Module Name: PeiSmbusLib.c
  15
  16 **/
  17
  18 #include "InternalSmbusLib.h"
  19
  20 /**
  21   Gets Smbus PPIs.
  22
  23   This internal function retrieves Smbus PPI from PPI database.
  24
  25   @param  PeiServices   An indirect pointer to the EFI_PEI_SERVICES published by the PEI Foundation.
  26
  27   @return The pointer to Smbus PPI.
  28
  29 **/
  30 EFI_PEI_SMBUS_PPI *
  31 InternalGetSmbusPpi (
  32   EFI_PEI_SERVICES      **PeiServices
  33   )
  34 {
  35   EFI_STATUS            Status;
  36   EFI_PEI_SMBUS_PPI     *SmbusPpi;
  37
  38   Status = (*PeiServices)->LocatePpi (PeiServices, &gEfiPeiSmbusPpiGuid, 0, NULL, (VOID **) &SmbusPpi);
  39   ASSERT_EFI_ERROR (Status);
  40   ASSERT (SmbusPpi != NULL);
  41
  42   return SmbusPpi;
  43 }
  44
  45 /**
  46   Executes an SMBus operation to an SMBus controller.
  47
  48   This function provides a standard way to execute Smbus script
  49   as defined in the SmBus Specification. The data can either be of
  50   the Length byte, word, or a block of data.
  51
  52   @param  SmbusOperation  Signifies which particular SMBus hardware protocol instance that it will use to
  53                           execute the SMBus transactions.
  54   @param  SmBusAddress    Address that encodes the SMBUS Slave Address,
  55                           SMBUS Command, SMBUS Data Length, and PEC.
  56   @param  Length          Signifies the number of bytes that this operation will do. The maximum number of
  57                           bytes can be revision specific and operation specific.
  58   @param  Buffer          Contains the value of data to execute to the SMBus slave device. Not all operations
  59                           require this argument. The length of this buffer is identified by Length.
  60   @param  Status          Return status for the executed command.
  61                           This is an optional parameter and may be NULL.
  62
  63   @return The actual number of bytes that are executed for this operation..
  64
  65 **/
  66 UINTN
  67 InternalSmBusExec (
  68   IN     EFI_SMBUS_OPERATION        SmbusOperation,
  69   IN     UINTN                      SmBusAddress,
  70   IN     UINTN                      Length,
  71   IN     VOID                       *Buffer,
  72      OUT RETURN_STATUS              *Status        OPTIONAL
  73   )
  74 {
  75   EFI_PEI_SMBUS_PPI         *SmbusPpi;
  76   EFI_PEI_SERVICES          **PeiServices;
  77   RETURN_STATUS             ReturnStatus;
  78   EFI_SMBUS_DEVICE_ADDRESS  SmbusDeviceAddress;
  79
  80   PeiServices = GetPeiServicesTablePointer ();
  81   SmbusPpi    = InternalGetSmbusPpi (PeiServices);
  82   SmbusDeviceAddress.SmbusDeviceAddress = SMBUS_LIB_SLAVE_ADDRESS (SmBusAddress);
  83
  84   ReturnStatus = SmbusPpi->Execute (
  85                              PeiServices,
  86                              SmbusPpi,
  87                              SmbusDeviceAddress,
  88                              SMBUS_LIB_COMMAND (SmBusAddress),
  89                              SmbusOperation,
  90                              SMBUS_LIB_PEC (SmBusAddress),
  91                              &Length,
  92                              Buffer
  93                              );
  94   if (Status != NULL) {
  95     *Status = ReturnStatus;
  96   }
  97
  98   return Length;
  99 }
 100
 101 /**
 102   Assigns an SMBUS slave addresses.
 103
 104   Assigns the SMBUS device specified by Uuid the slave address specified by SmBusAddress.
 105   The status of the executed command is returned.
 106   If Command in SmBusAddress is not zero, then ASSERT().
 107   If Length in SmBusAddress is not zero, then ASSERT().
 108   If PEC in SmBusAddress is set, then ASSERT().
 109   If any reserved bits of SmBusAddress are set, then ASSERT().
 110
 111   @param  SmBusAddress        Address that encodes the SMBUS Slave Address,
 112                               SMBUS Command, SMBUS Data Length, and PEC.
 113   @param  Uuid                Pointer to the UUID of the device to assign a slave address.
 114                               It will assign to all SMBUS slave devices if it is NULL.
 115
 116   @retval RETURN_SUCCESS      The SMBUS command was executed.
 117   @retval RETURN_TIMEOUT      A timeout occurred while executing the SMBUS command.
 118   @retval RETURN_DEVICE_ERROR The request was not completed because a failure reflected
 119                               in the Host Status Register bit.
 120                               Device errors are a result of a transaction collision, illegal command field,
 121                               unclaimed cycle (host initiated), or bus errors (collisions).
 122
 123 **/
 124 RETURN_STATUS
 125 InternalSmBusArpDevice (
 126   IN UINTN          SmBusAddress,
 127   IN CONST GUID     *Uuid       OPTIONAL
 128   )
 129 {
 130   EFI_PEI_SMBUS_PPI         *SmbusPpi;
 131   EFI_PEI_SERVICES          **PeiServices;
 132   EFI_SMBUS_DEVICE_ADDRESS  SmbusDeviceAddress;
 133
 134   PeiServices = GetPeiServicesTablePointer ();
 135   SmbusPpi    = InternalGetSmbusPpi (PeiServices);
 136
 137   SmbusDeviceAddress.SmbusDeviceAddress = SMBUS_LIB_SLAVE_ADDRESS (SmBusAddress);
 138   return (RETURN_STATUS) SmbusPpi->ArpDevice (
 139                                      PeiServices,
 140                                      SmbusPpi,
 141                                      (BOOLEAN) (Uuid == NULL),
 142                                      (EFI_SMBUS_UDID *) Uuid,
 143                                      &SmbusDeviceAddress
 144                                      );
 145 }
 146
 147 /**
 148   Retrieves the mapping of all the SMBus devices.
 149
 150   The GetArpMap() function returns the mapping of all the SMBus devices
 151   that are enumerated by the SMBus host driver.
 152
 153   @param  Length              Size of the buffer that contains the SMBus device map.
 154   @param  SmbusDeviceMap      The pointer to the device map as enumerated by the SMBus controller driver.
 155
 156   @retval RETURN_SUCCESS      The SMBUS command was executed.
 157   @retval RETURN_TIMEOUT      A timeout occurred while executing the SMBUS command.
 158   @retval RETURN_DEVICE_ERROR The request was not completed because a failure reflected
 159                               in the Host Status Register bit.
 160                               Device errors are a result of a transaction collision, illegal command field,
 161                               unclaimed cycle (host initiated), or bus errors (collisions).
 162
 163 **/
 164 RETURN_STATUS
 165 InternalGetArpMap (
 166   OUT UINTN                         *Length,
 167   OUT EFI_SMBUS_DEVICE_MAP          **SmbusDeviceMap
 168   )
 169 {
 170   EFI_PEI_SMBUS_PPI         *SmbusPpi;
 171   EFI_PEI_SERVICES          **PeiServices;
 172
 173   PeiServices  = GetPeiServicesTablePointer ();
 174   SmbusPpi     = InternalGetSmbusPpi (PeiServices);
 175
 176   return (RETURN_STATUS) SmbusPpi->GetArpMap (PeiServices, SmbusPpi, Length, SmbusDeviceMap);
 177 }