ArmPkg/Drivers/CpuDxe/AArch64/Mmu.c

   1 /*++
   2
   3 Copyright (c) 2009, Hewlett-Packard Company. All rights reserved.<BR>
   4 Portions copyright (c) 2010, Apple Inc. All rights reserved.<BR>
   5 Portions copyright (c) 2011-2013, ARM Ltd. All rights reserved.<BR>
   6
   7 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
  18 #include <Library/MemoryAllocationLib.h>
  19 #include "CpuDxe.h"
  20
  21 #define TT_ATTR_INDX_INVALID    ((UINT32)~0)
  22
  23 STATIC
  24 UINT64
  25 GetFirstPageAttribute (
  26   IN UINT64  *FirstLevelTableAddress,
  27   IN UINTN    TableLevel
  28   )
  29 {
  30   UINT64 FirstEntry;
  31
  32   // Get the first entry of the table
  33   FirstEntry = *FirstLevelTableAddress;
  34
  35   if ((FirstEntry & TT_TYPE_MASK) == TT_TYPE_TABLE_ENTRY) {
  36     // Only valid for Levels 0, 1 and 2
  37     ASSERT (TableLevel < 3);
  38
  39     // Get the attribute of the subsequent table
  40     return GetFirstPageAttribute ((UINT64*)(FirstEntry & TT_ADDRESS_MASK_DESCRIPTION_TABLE), TableLevel + 1);
  41   } else if (((FirstEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY) ||
  42              ((TableLevel == 3) && ((FirstEntry & TT_TYPE_MASK) == TT_TYPE_BLOCK_ENTRY_LEVEL3)))
  43   {
  44     return FirstEntry & TT_ATTR_INDX_MASK;
  45   } else {
  46     return TT_ATTR_INDX_INVALID;
  47   }
  48 }
  49
  50 STATIC
  51 UINT64
  52 GetNextEntryAttribute (
  53   IN     UINT64 *TableAddress,
  54   IN     UINTN   EntryCount,
  55   IN     UINTN   TableLevel,
  56   IN     UINT64  BaseAddress,
  57   IN OUT UINT32 *PrevEntryAttribute,
  58   IN OUT UINT64 *StartGcdRegion
  59   )
  60 {
  61   UINTN                             Index;
  62   UINT64                            Entry;
  63   UINT32                            EntryAttribute;
  64   UINT32                            EntryType;
  65   EFI_STATUS                        Status;
  66   UINTN                             NumberOfDescriptors;
  67   EFI_GCD_MEMORY_SPACE_DESCRIPTOR  *MemorySpaceMap;
  68
  69   // Get the memory space map from GCD
  70   MemorySpaceMap = NULL;
  71   Status = gDS->GetMemorySpaceMap (&NumberOfDescriptors, &MemorySpaceMap);
  72   ASSERT_EFI_ERROR (Status);
  73
  74   // We cannot get more than 3-level page table
  75   ASSERT (TableLevel <= 3);
  76
  77   // While the top level table might not contain TT_ENTRY_COUNT entries;
  78   // the subsequent ones should be filled up
  79   for (Index = 0; Index < EntryCount; Index++) {
  80     Entry = TableAddress[Index];
  81     EntryType = Entry & TT_TYPE_MASK;
  82     EntryAttribute = Entry  & TT_ATTR_INDX_MASK;
  83
  84     // If Entry is a Table Descriptor type entry then go through the sub-level table
  85     if ((EntryType == TT_TYPE_BLOCK_ENTRY) ||
  86         ((TableLevel == 3) && (EntryType == TT_TYPE_BLOCK_ENTRY_LEVEL3))) {
  87       if ((*PrevEntryAttribute == TT_ATTR_INDX_INVALID) || (EntryAttribute != *PrevEntryAttribute)) {
  88         if (*PrevEntryAttribute != TT_ATTR_INDX_INVALID) {
  89           // Update GCD with the last region
  90           SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors,
  91               *StartGcdRegion,
  92               (BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel)) - 1) - *StartGcdRegion,
  93               PageAttributeToGcdAttribute (EntryAttribute));
  94         }
  95
  96         // Start of the new region
  97         *StartGcdRegion = BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel));
  98         *PrevEntryAttribute = EntryAttribute;
  99       } else {
 100         continue;
 101       }
 102     } else if (EntryType == TT_TYPE_TABLE_ENTRY) {
 103       // Table Entry type is only valid for Level 0, 1, 2
 104       ASSERT (TableLevel < 3);
 105
 106       // Increase the level number and scan the sub-level table
 107       GetNextEntryAttribute ((UINT64*)(Entry & TT_ADDRESS_MASK_DESCRIPTION_TABLE),
 108                              TT_ENTRY_COUNT, TableLevel + 1,
 109                              (BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel))),
 110                              PrevEntryAttribute, StartGcdRegion);
 111     } else {
 112       if (*PrevEntryAttribute != TT_ATTR_INDX_INVALID) {
 113         // Update GCD with the last region
 114         SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors,
 115             *StartGcdRegion,
 116             (BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel)) - 1) - *StartGcdRegion,
 117             PageAttributeToGcdAttribute (EntryAttribute));
 118
 119         // Start of the new region
 120         *StartGcdRegion = BaseAddress + (Index * TT_ADDRESS_AT_LEVEL(TableLevel));
 121         *PrevEntryAttribute = TT_ATTR_INDX_INVALID;
 122       }
 123     }
 124   }
 125
 126   FreePool (MemorySpaceMap);
 127
 128   return BaseAddress + (EntryCount * TT_ADDRESS_AT_LEVEL(TableLevel));
 129 }
 130
 131 EFI_STATUS
 132 SyncCacheConfig (
 133   IN  EFI_CPU_ARCH_PROTOCOL *CpuProtocol
 134   )
 135 {
 136   EFI_STATUS                          Status;
 137   UINT32                              PageAttribute = 0;
 138   UINT64                             *FirstLevelTableAddress;
 139   UINTN                               TableLevel;
 140   UINTN                               TableCount;
 141   UINTN                               NumberOfDescriptors;
 142   EFI_GCD_MEMORY_SPACE_DESCRIPTOR    *MemorySpaceMap;
 143   UINTN                               Tcr;
 144   UINTN                               T0SZ;
 145   UINT64                              BaseAddressGcdRegion;
 146   UINT64                              EndAddressGcdRegion;
 147
 148   // This code assumes MMU is enabled and filed with section translations
 149   ASSERT (ArmMmuEnabled ());
 150
 151   //
 152   // Get the memory space map from GCD
 153   //
 154   MemorySpaceMap = NULL;
 155   Status = gDS->GetMemorySpaceMap (&NumberOfDescriptors, &MemorySpaceMap);
 156   ASSERT_EFI_ERROR (Status);
 157
 158   // The GCD implementation maintains its own copy of the state of memory space attributes.  GCD needs
 159   // to know what the initial memory space attributes are.  The CPU Arch. Protocol does not provide a
 160   // GetMemoryAttributes function for GCD to get this so we must resort to calling GCD (as if we were
 161   // a client) to update its copy of the attributes.  This is bad architecture and should be replaced
 162   // with a way for GCD to query the CPU Arch. driver of the existing memory space attributes instead.
 163
 164   // Obtain page table base
 165   FirstLevelTableAddress = (UINT64*)(ArmGetTTBR0BaseAddress ());
 166
 167   // Get Translation Control Register value
 168   Tcr = ArmGetTCR ();
 169   // Get Address Region Size
 170   T0SZ = Tcr & TCR_T0SZ_MASK;
 171
 172   // Get the level of the first table for the indicated Address Region Size
 173   GetRootTranslationTableInfo (T0SZ, &TableLevel, &TableCount);
 174
 175   // First Attribute of the Page Tables
 176   PageAttribute = GetFirstPageAttribute (FirstLevelTableAddress, TableLevel);
 177
 178   // We scan from the start of the memory map (ie: at the address 0x0)
 179   BaseAddressGcdRegion = 0x0;
 180   EndAddressGcdRegion = GetNextEntryAttribute (FirstLevelTableAddress,
 181                                                TableCount, TableLevel,
 182                                                BaseAddressGcdRegion,
 183                                                &PageAttribute, &BaseAddressGcdRegion);
 184
 185   // Update GCD with the last region
 186   SetGcdMemorySpaceAttributes (MemorySpaceMap, NumberOfDescriptors,
 187       BaseAddressGcdRegion,
 188       EndAddressGcdRegion - BaseAddressGcdRegion,
 189       PageAttributeToGcdAttribute (PageAttribute));
 190
 191   FreePool (MemorySpaceMap);
 192
 193   return EFI_SUCCESS;
 194 }