IntelFrameworkPkg/Include/Protocol/SmmAccess.h

   1 /** @file
   2   This file declares the SMM SMRAM Access abstraction protocol, which is used to control
   3   the visibility of the SMRAM on the platform. The expectation is
   4   that the north bridge or memory controller would publish this protocol.
   5   For example, the Memory Controller Hub (MCH) has the hardware provision for this
   6   type of control. Because of the protected, distinguished class of memory for IA-32
   7   systems, the expectation is that this protocol would be supported only on IA-32 systems.
   8
   9 Copyright (c) 2007 - 2018, Intel Corporation. All rights reserved.<BR>
  10 SPDX-License-Identifier: BSD-2-Clause-Patent
  11
  12   @par Revision Reference:
  13   This Protocol is defined in Framework of EFI SMM Core Interface Spec
  14   Version 0.9.
  15 **/
  16
  17 #ifndef _SMM_ACCESS_H_
  18 #define _SMM_ACCESS_H_
  19
  20 #include <Guid/SmramMemoryReserve.h>
  21
  22 typedef struct _EFI_SMM_ACCESS_PROTOCOL  EFI_SMM_ACCESS_PROTOCOL;
  23
  24 #define EFI_SMM_ACCESS_PROTOCOL_GUID \
  25   { \
  26     0x3792095a, 0xe309, 0x4c1e, {0xaa, 0x01, 0x85, 0xf5, 0x65, 0x5a, 0x17, 0xf1 } \
  27   }
  28
  29 //
  30 // SMM Access specification Member Function
  31 //
  32 /**
  33   Opens the SMRAM area to be accessible by a boot-service driver.
  34
  35   @param  This                  The EFI_SMM_ACCESS_PROTOCOL instance.
  36   @param  DescriptorIndex       Indicates that the driver wishes to open
  37                                 the memory tagged by this index.
  38
  39   @retval EFI_SUCCESS           The operation was successful.
  40   @retval EFI_INVALID_PARAMETER The given DescriptorIndex is not supported.
  41   @retval EFI_NOT_STARTED       The SMM base service has not been initialized.
  42
  43 **/
  44 typedef
  45 EFI_STATUS
  46 (EFIAPI *EFI_SMM_OPEN)(
  47   IN EFI_SMM_ACCESS_PROTOCOL         *This,
  48   UINTN                              DescriptorIndex
  49   );
  50
  51 /**
  52   Inhibits access to the SMRAM.
  53
  54   @param  This                  The EFI_SMM_ACCESS_PROTOCOL instance.
  55   @param  DescriptorIndex       Indicates that the driver wishes to close
  56                                 the memory tagged by this index.
  57
  58   @retval EFI_SUCCESS           The operation was successful.
  59   @retval EFI_DEVICE_ERROR      The given DescriptorIndex is not open.
  60   @retval EFI_INVALID_PARAMETER The given DescriptorIndex is not supported.
  61   @retval EFI_NOT_STARTED       The SMM base service has not been initialized.
  62
  63 **/
  64 typedef
  65 EFI_STATUS
  66 (EFIAPI *EFI_SMM_CLOSE)(
  67   IN EFI_SMM_ACCESS_PROTOCOL          *This,
  68   UINTN                               DescriptorIndex
  69   );
  70
  71 /**
  72   Inhibits access to the SMRAM.
  73
  74   @param  This                  The EFI_SMM_ACCESS_PROTOCOL instance.
  75   @param  DescriptorIndex       Indicates that the driver wishes to lock
  76                                 the memory tagged by this index.
  77
  78   @retval EFI_SUCCESS           The operation was successful.
  79   @retval EFI_DEVICE_ERROR      The given DescriptorIndex is not open.
  80   @retval EFI_INVALID_PARAMETER The given DescriptorIndex is not supported.
  81   @retval EFI_NOT_STARTED       The SMM base service has not been initialized.
  82
  83 **/
  84 typedef
  85 EFI_STATUS
  86 (EFIAPI *EFI_SMM_LOCK)(
  87   IN EFI_SMM_ACCESS_PROTOCOL         *This,
  88   UINTN                              DescriptorIndex
  89   );
  90
  91 /**
  92   Queries the memory controller for the possible regions that will support SMRAM.
  93
  94   @param  This                  The EFI_SMM_ACCESS_PROTOCOL instance.
  95   @param  SmramMapSize          A pointer to the size, in bytes, of the SmramMemoryMap buffer.
  96   @param  SmramMap              A pointer to the buffer in which firmware places the current memory map.
  97
  98   @retval EFI_SUCCESS           The chipset supported the given resource.
  99   @retval EFI_BUFFER_TOO_SMALL  The SmramMap parameter was too small.
 100
 101 **/
 102 typedef
 103 EFI_STATUS
 104 (EFIAPI *EFI_SMM_CAPABILITIES)(
 105   IN EFI_SMM_ACCESS_PROTOCOL             *This,
 106   IN OUT UINTN                           *SmramMapSize,
 107   IN OUT EFI_SMRAM_DESCRIPTOR            *SmramMap
 108   );
 109
 110 /**
 111   This protocol is used to control the visibility of the SMRAM on the platform.
 112 **/
 113 struct _EFI_SMM_ACCESS_PROTOCOL {
 114   EFI_SMM_OPEN          Open;             ///< Opens the SMRAM.
 115   EFI_SMM_CLOSE         Close;            ///< Closes the SMRAM.
 116   EFI_SMM_LOCK          Lock;             ///< Locks the SMRAM.
 117   EFI_SMM_CAPABILITIES  GetCapabilities;  ///< Gets information on possible SMRAM regions.
 118   BOOLEAN               LockState;        ///< Indicates the current state of the SMRAM. Set to TRUE if any region is locked.
 119   BOOLEAN               OpenState;        ///< Indicates the current state of the SMRAM. Set to TRUE if any region is open.
 120 };
 121
 122 extern EFI_GUID gEfiSmmAccessProtocolGuid;
 123
 124 #endif