MdePkg/Include/Protocol/MmCpuIo.h

   1 /** @file
   2   MM CPU I/O 2 protocol as defined in the PI 1.5 specification.
   3
   4   This protocol provides CPU I/O and memory access within MM.
   5
   6   Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
   7   SPDX-License-Identifier: BSD-2-Clause-Patent
   8
   9 **/
  10
  11 #ifndef _MM_CPU_IO_H_
  12 #define _MM_CPU_IO_H_
  13
  14 #define EFI_MM_CPU_IO_PROTOCOL_GUID \
  15   { \
  16     0x3242A9D8, 0xCE70, 0x4AA0, { 0x95, 0x5D, 0x5E, 0x7B, 0x14, 0x0D, 0xE4, 0xD2 } \
  17   }
  18
  19 typedef struct _EFI_MM_CPU_IO_PROTOCOL EFI_MM_CPU_IO_PROTOCOL;
  20
  21 ///
  22 /// Width of the MM CPU I/O operations
  23 ///
  24 typedef enum {
  25   MM_IO_UINT8  = 0,
  26   MM_IO_UINT16 = 1,
  27   MM_IO_UINT32 = 2,
  28   MM_IO_UINT64 = 3
  29 } EFI_MM_IO_WIDTH;
  30
  31 /**
  32   Provides the basic memory and I/O interfaces used toabstract accesses to devices.
  33
  34   The I/O operations are carried out exactly as requested.  The caller is
  35   responsible for any alignment and I/O width issues that the bus, device,
  36   platform, or type of I/O might require.
  37
  38   @param[in]      This     The EFI_MM_CPU_IO_PROTOCOL instance.
  39   @param[in]      Width    Signifies the width of the I/O operations.
  40   @param[in]      Address  The base address of the I/O operations.  The caller is
  41                            responsible for aligning the Address if required.
  42   @param[in]      Count    The number of I/O operations to perform.
  43   @param[in,out]  Buffer   For read operations, the destination buffer to store
  44                            the results.  For write operations, the source buffer
  45                            from which to write data.
  46
  47   @retval EFI_SUCCESS            The data was read from or written to the device.
  48   @retval EFI_UNSUPPORTED        The Address is not valid for this system.
  49   @retval EFI_INVALID_PARAMETER  Width or Count, or both, were invalid.
  50   @retval EFI_OUT_OF_RESOURCES   The request could not be completed due to a lack
  51                                  of resources.
  52 **/
  53 typedef
  54 EFI_STATUS
  55 (EFIAPI *EFI_MM_CPU_IO)(
  56   IN     CONST EFI_MM_CPU_IO_PROTOCOL    *This,
  57   IN     EFI_MM_IO_WIDTH                 Width,
  58   IN     UINT64                          Address,
  59   IN     UINTN                           Count,
  60   IN OUT VOID                            *Buffer
  61   );
  62
  63 typedef struct {
  64   ///
  65   /// This service provides the various modalities of memory and I/O read.
  66   ///
  67   EFI_MM_CPU_IO    Read;
  68   ///
  69   /// This service provides the various modalities of memory and I/O write.
  70   ///
  71   EFI_MM_CPU_IO    Write;
  72 } EFI_MM_IO_ACCESS;
  73
  74 ///
  75 /// MM CPU I/O Protocol provides CPU I/O and memory access within MM.
  76 ///
  77 struct _EFI_MM_CPU_IO_PROTOCOL {
  78   ///
  79   /// Allows reads and writes to memory-mapped I/O space.
  80   ///
  81   EFI_MM_IO_ACCESS    Mem;
  82   ///
  83   /// Allows reads and writes to I/O space.
  84   ///
  85   EFI_MM_IO_ACCESS    Io;
  86 };
  87
  88 extern EFI_GUID  gEfiMmCpuIoProtocolGuid;
  89
  90 #endif