MdePkg/Include/Protocol/SmmCpuIo.h

   1 /** @file
   2   SMM CPU I/O protocol as defined in the PI 1.2 specification.
   3
   4   This protocol provides CPU I/O and memory access within SMM.
   5
   6   Copyright (c) 2009, Intel Corporation
   7   All rights reserved. This program and the accompanying materials
   8   are licensed and made available under the terms and conditions of the BSD License
   9   which accompanies this distribution.  The full text of the license may be found at
  10   http://opensource.org/licenses/bsd-license.php
  11
  12   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14
  15 **/
  16
  17 #ifndef _SMM_CPU_IO_H_
  18 #define _SMM_CPU_IO_H_
  19
  20 #define EFI_SMM_CPU_IO_PROTOCOL_GUID \
  21   { \
  22     0x3242A9D8, 0xCE70, 0x4AA0, { 0x95, 0x5D, 0x5E, 0x7B, 0x14, 0x0D, 0xE4, 0xD2 } \
  23   }
  24
  25 typedef struct _EFI_SMM_CPU_IO_PROTOCOL  EFI_SMM_CPU_IO_PROTOCOL;
  26
  27 ///
  28 /// Width of the SMM CPU I/O operations
  29 ///
  30 typedef enum {
  31   SMM_IO_UINT8  = 0,
  32   SMM_IO_UINT16 = 1,
  33   SMM_IO_UINT32 = 2,
  34   SMM_IO_UINT64 = 3
  35 } EFI_SMM_IO_WIDTH;
  36
  37 /**
  38   Provides the basic memory and I/O interfaces used toabstract accesses to devices.
  39
  40   The I/O operations are carried out exactly as requested.  The caller is responsible for any alignment
  41   and I/O width issues that the bus, device, platform, or type of I/O might require.
  42
  43   @param[in]      This           The EFI_SMM_CPU_IO_PROTOCOL instance.
  44   @param[in]      Width          Signifies the width of the I/O operations.
  45   @param[in]      Address        The base address of the I/O operations.
  46                                  The caller is responsible for aligning the Address if required.
  47   @param[in]      Count          The number of I/O operations to perform.
  48   @param[in,out]  Buffer         For read operations, the destination buffer to store the results.
  49                                  For write operations, the source buffer from which to write data.
  50
  51   @retval EFI_SUCCESS            The data was read from or written to the device.
  52   @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  53   @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
  54   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack of resources.
  55 **/
  56 typedef
  57 EFI_STATUS
  58 (EFIAPI *EFI_SMM_CPU_IO)(
  59   IN CONST EFI_SMM_CPU_IO_PROTOCOL  *This,
  60   IN EFI_SMM_IO_WIDTH               Width,
  61   IN UINT64                         Address,
  62   IN UINTN                          Count,
  63   IN OUT VOID                       *Buffer
  64   );
  65
  66 typedef struct {
  67   ///
  68   /// This service provides the various modalities of memory and I/O read.
  69   ///
  70   EFI_SMM_CPU_IO  Read;
  71   ///
  72   /// This service provides the various modalities of memory and I/O write.
  73   ///
  74   EFI_SMM_CPU_IO  Write;
  75 } EFI_SMM_IO_ACCESS;
  76
  77 ///
  78 /// SMM CPU I/O Protocol provides CPU I/O and memory access within SMM.
  79 ///
  80 typedef struct _EFI_SMM_CPU_IO_PROTOCOL {
  81   EFI_SMM_IO_ACCESS Mem;  ///< Allows reads and writes to memory-mapped I/O space.
  82   EFI_SMM_IO_ACCESS Io;   ///< Allows reads and writes to I/O space.
  83 };
  84
  85 extern EFI_GUID gEfiSmmCpuIoProtocolGuid;
  86
  87 #endif