OvmfPkg/Csm/CsmSupportLib/LegacyRegion.h

   1 /** @file
   2   Legacy Region Support
   3
   4   Copyright (c) 2008 - 2016, Intel Corporation. All rights reserved.<BR>
   5
   6   This program and the accompanying materials are
   7   licensed and made available under the terms and conditions of the BSD License
   8   which accompanies this distribution.  The full text of the license may be found at
   9   http://opensource.org/licenses/bsd-license.php
  10
  11   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  12   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  13
  14 **/
  15
  16 #ifndef _LEGACY_REGION_DXE_H_
  17 #define _LEGACY_REGION_DXE_H_
  18
  19 #include <PiDxe.h>
  20
  21 #include <Protocol/LegacyRegion2.h>
  22
  23 #include <IndustryStandard/Pci.h>
  24 #include <IndustryStandard/Q35MchIch9.h>
  25 #include <IndustryStandard/I440FxPiix4.h>
  26
  27 #include <Library/PciLib.h>
  28 #include <Library/PcdLib.h>
  29 #include <Library/DebugLib.h>
  30 #include <Library/MemoryAllocationLib.h>
  31 #include <Library/UefiBootServicesTableLib.h>
  32
  33 #define PAM_BASE_ADDRESS   0xc0000
  34 #define PAM_LIMIT_ADDRESS  BASE_1MB
  35
  36 //
  37 // Describes Legacy Region blocks and status.
  38 //
  39 typedef struct {
  40   UINT32  Start;
  41   UINT32  Length;
  42   BOOLEAN ReadEnabled;
  43   BOOLEAN WriteEnabled;
  44 } LEGACY_MEMORY_SECTION_INFO;
  45
  46 //
  47 // Provides a map of the PAM registers and bits used to set Read/Write access.
  48 //
  49 typedef struct {
  50   UINTN   PAMRegPciLibAddress;
  51   UINT8   ReadEnableData;
  52   UINT8   WriteEnableData;
  53 } PAM_REGISTER_VALUE;
  54
  55 /**
  56   Modify the hardware to allow (decode) or disallow (not decode) memory reads in a region.
  57
  58   If the On parameter evaluates to TRUE, this function enables memory reads in the address range
  59   Start to (Start + Length - 1).
  60   If the On parameter evaluates to FALSE, this function disables memory reads in the address range
  61   Start to (Start + Length - 1).
  62
  63   @param  This[in]              Indicates the EFI_LEGACY_REGION_PROTOCOL instance.
  64   @param  Start[in]             The beginning of the physical address of the region whose attributes
  65                                 should be modified.
  66   @param  Length[in]            The number of bytes of memory whose attributes should be modified.
  67                                 The actual number of bytes modified may be greater than the number
  68                                 specified.
  69   @param  Granularity[out]      The number of bytes in the last region affected. This may be less
  70                                 than the total number of bytes affected if the starting address
  71                                 was not aligned to a region's starting address or if the length
  72                                 was greater than the number of bytes in the first region.
  73   @param  On[in]                Decode / Non-Decode flag.
  74
  75   @retval EFI_SUCCESS           The region's attributes were successfully modified.
  76   @retval EFI_INVALID_PARAMETER If Start or Length describe an address not in the Legacy Region.
  77
  78 **/
  79 EFI_STATUS
  80 EFIAPI
  81 LegacyRegion2Decode (
  82   IN  EFI_LEGACY_REGION2_PROTOCOL  *This,
  83   IN  UINT32                       Start,
  84   IN  UINT32                       Length,
  85   OUT UINT32                       *Granularity,
  86   IN  BOOLEAN                      *On
  87   );
  88
  89 /**
  90   Modify the hardware to disallow memory writes in a region.
  91
  92   This function changes the attributes of a memory range to not allow writes.
  93
  94   @param  This[in]              Indicates the EFI_LEGACY_REGION_PROTOCOL instance.
  95   @param  Start[in]             The beginning of the physical address of the region whose
  96                                 attributes should be modified.
  97   @param  Length[in]            The number of bytes of memory whose attributes should be modified.
  98                                 The actual number of bytes modified may be greater than the number
  99                                 specified.
 100   @param  Granularity[out]      The number of bytes in the last region affected. This may be less
 101                                 than the total number of bytes affected if the starting address was
 102                                 not aligned to a region's starting address or if the length was
 103                                 greater than the number of bytes in the first region.
 104
 105   @retval EFI_SUCCESS           The region's attributes were successfully modified.
 106   @retval EFI_INVALID_PARAMETER If Start or Length describe an address not in the Legacy Region.
 107
 108 **/
 109 EFI_STATUS
 110 EFIAPI
 111 LegacyRegion2Lock (
 112   IN  EFI_LEGACY_REGION2_PROTOCOL *This,
 113   IN  UINT32                      Start,
 114   IN  UINT32                      Length,
 115   OUT UINT32                      *Granularity
 116   );
 117
 118 /**
 119   Modify the hardware to disallow memory attribute changes in a region.
 120
 121   This function makes the attributes of a region read only. Once a region is boot-locked with this
 122   function, the read and write attributes of that region cannot be changed until a power cycle has
 123   reset the boot-lock attribute. Calls to Decode(), Lock() and Unlock() will have no effect.
 124
 125   @param  This[in]              Indicates the EFI_LEGACY_REGION_PROTOCOL instance.
 126   @param  Start[in]             The beginning of the physical address of the region whose
 127                                 attributes should be modified.
 128   @param  Length[in]            The number of bytes of memory whose attributes should be modified.
 129                                 The actual number of bytes modified may be greater than the number
 130                                 specified.
 131   @param  Granularity[out]      The number of bytes in the last region affected. This may be less
 132                                 than the total number of bytes affected if the starting address was
 133                                 not aligned to a region's starting address or if the length was
 134                                 greater than the number of bytes in the first region.
 135
 136   @retval EFI_SUCCESS           The region's attributes were successfully modified.
 137   @retval EFI_INVALID_PARAMETER If Start or Length describe an address not in the Legacy Region.
 138   @retval EFI_UNSUPPORTED       The chipset does not support locking the configuration registers in
 139                                 a way that will not affect memory regions outside the legacy memory
 140                                 region.
 141
 142 **/
 143 EFI_STATUS
 144 EFIAPI
 145 LegacyRegion2BootLock (
 146   IN EFI_LEGACY_REGION2_PROTOCOL          *This,
 147   IN  UINT32                              Start,
 148   IN  UINT32                              Length,
 149   OUT UINT32                              *Granularity
 150   );
 151
 152 /**
 153   Modify the hardware to allow memory writes in a region.
 154
 155   This function changes the attributes of a memory range to allow writes.
 156
 157   @param  This[in]              Indicates the EFI_LEGACY_REGION_PROTOCOL instance.
 158   @param  Start[in]             The beginning of the physical address of the region whose
 159                                 attributes should be modified.
 160   @param  Length[in]            The number of bytes of memory whose attributes should be modified.
 161                                 The actual number of bytes modified may be greater than the number
 162                                 specified.
 163   @param  Granularity[out]      The number of bytes in the last region affected. This may be less
 164                                 than the total number of bytes affected if the starting address was
 165                                 not aligned to a region's starting address or if the length was
 166                                 greater than the number of bytes in the first region.
 167
 168   @retval EFI_SUCCESS           The region's attributes were successfully modified.
 169   @retval EFI_INVALID_PARAMETER If Start or Length describe an address not in the Legacy Region.
 170
 171 **/
 172 EFI_STATUS
 173 EFIAPI
 174 LegacyRegion2Unlock (
 175   IN  EFI_LEGACY_REGION2_PROTOCOL  *This,
 176   IN  UINT32                       Start,
 177   IN  UINT32                       Length,
 178   OUT UINT32                       *Granularity
 179   );
 180
 181 /**
 182   Get region information for the attributes of the Legacy Region.
 183
 184   This function is used to discover the granularity of the attributes for the memory in the legacy
 185   region. Each attribute may have a different granularity and the granularity may not be the same
 186   for all memory ranges in the legacy region.
 187
 188   @param  This[in]              Indicates the EFI_LEGACY_REGION_PROTOCOL instance.
 189   @param  DescriptorCount[out]  The number of region descriptor entries returned in the Descriptor
 190                                 buffer.
 191   @param  Descriptor[out]       A pointer to a pointer used to return a buffer where the legacy
 192                                 region information is deposited. This buffer will contain a list of
 193                                 DescriptorCount number of region descriptors.  This function will
 194                                 provide the memory for the buffer.
 195
 196   @retval EFI_SUCCESS           The region's attributes were successfully modified.
 197   @retval EFI_INVALID_PARAMETER If Start or Length describe an address not in the Legacy Region.
 198
 199 **/
 200 EFI_STATUS
 201 EFIAPI
 202 LegacyRegionGetInfo (
 203   IN  EFI_LEGACY_REGION2_PROTOCOL   *This,
 204   OUT UINT32                        *DescriptorCount,
 205   OUT EFI_LEGACY_REGION_DESCRIPTOR  **Descriptor
 206   );
 207
 208 #endif
 209