MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/X64/SetIdtEntry.c

   1 /** @file
   2   Set a IDT entry for debug purpose
   3
   4   Set a IDT entry for interrupt vector 3 for debug purpose for x64 platform
   5
   6 Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>
   7
   8 This program and the accompanying materials
   9 are licensed and made available under the terms and conditions of the BSD License
  10 which accompanies this distribution.  The full text of the license may be found at
  11 http://opensource.org/licenses/bsd-license.php
  12
  13 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15
  16 **/
  17 #include "ScriptExecute.h"
  18
  19 //
  20 // 8 extra pages for PF handler.
  21 //
  22 #define EXTRA_PAGE_TABLE_PAGES      8
  23
  24 #define IA32_PG_P                   BIT0
  25 #define IA32_PG_RW                  BIT1
  26 #define IA32_PG_PS                  BIT7
  27
  28 UINT64                              mPhyMask;
  29 VOID                                *mOriginalHandler;
  30 UINTN                               mPageFaultBuffer;
  31 UINTN                               mPageFaultIndex = 0;
  32 //
  33 // Store the uplink information for each page being used.
  34 //
  35 UINT64                              *mPageFaultUplink[EXTRA_PAGE_TABLE_PAGES];
  36
  37 /**
  38   Page fault handler.
  39
  40 **/
  41 VOID
  42 EFIAPI
  43 PageFaultHandlerHook (
  44   VOID
  45   );
  46
  47 /**
  48   Hook IDT with our page fault handler so that the on-demand paging works on page fault.
  49
  50   @param  IdtEntry  a pointer to IDT entry
  51
  52 **/
  53 VOID
  54 HookPageFaultHandler (
  55   IN IA32_IDT_GATE_DESCRIPTOR                   *IdtEntry
  56   )
  57 {
  58   UINT32         RegEax;
  59   UINT8          PhysicalAddressBits;
  60   UINTN          PageFaultHandlerHookAddress;
  61
  62   AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);
  63   if (RegEax >= 0x80000008) {
  64     AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);
  65     PhysicalAddressBits = (UINT8) RegEax;
  66   } else {
  67     PhysicalAddressBits = 36;
  68   }
  69   mPhyMask = LShiftU64 (1, PhysicalAddressBits) - 1;
  70   mPhyMask &= (1ull << 48) - SIZE_4KB;
  71
  72   //
  73   // Set Page Fault entry to catch >4G access
  74   //
  75   PageFaultHandlerHookAddress = (UINTN)PageFaultHandlerHook;
  76   mOriginalHandler = (VOID *)(UINTN)(LShiftU64 (IdtEntry->Bits.OffsetUpper, 32) + IdtEntry->Bits.OffsetLow + (IdtEntry->Bits.OffsetHigh << 16));
  77   IdtEntry->Bits.OffsetLow      = (UINT16)PageFaultHandlerHookAddress;
  78   IdtEntry->Bits.Selector       = (UINT16)AsmReadCs ();
  79   IdtEntry->Bits.Reserved_0     = 0;
  80   IdtEntry->Bits.GateType       = IA32_IDT_GATE_TYPE_INTERRUPT_32;
  81   IdtEntry->Bits.OffsetHigh     = (UINT16)(PageFaultHandlerHookAddress >> 16);
  82   IdtEntry->Bits.OffsetUpper    = (UINT32)(PageFaultHandlerHookAddress >> 32);
  83   IdtEntry->Bits.Reserved_1     = 0;
  84
  85   if (mPage1GSupport) {
  86     mPageFaultBuffer = (UINTN)(AsmReadCr3 () & mPhyMask) + EFI_PAGES_TO_SIZE(2);
  87   }else {
  88     mPageFaultBuffer = (UINTN)(AsmReadCr3 () & mPhyMask) + EFI_PAGES_TO_SIZE(6);
  89   }
  90   ZeroMem (mPageFaultUplink, sizeof (mPageFaultUplink));
  91 }
  92
  93 /**
  94   The function will check if current waking vector is long mode.
  95
  96   @param  AcpiS3Context                 a pointer to a structure of ACPI_S3_CONTEXT
  97
  98   @retval TRUE   Current context need long mode waking vector.
  99   @retval FALSE  Current context need not long mode waking vector.
 100 **/
 101 BOOLEAN
 102 IsLongModeWakingVector (
 103   IN ACPI_S3_CONTEXT                *AcpiS3Context
 104   )
 105 {
 106   EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE  *Facs;
 107
 108   Facs = (EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *) ((UINTN) (AcpiS3Context->AcpiFacsTable));
 109   if ((Facs == NULL) ||
 110       (Facs->Signature != EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE) ||
 111       ((Facs->FirmwareWakingVector == 0) && (Facs->XFirmwareWakingVector == 0)) ) {
 112     // Something wrong with FACS
 113     return FALSE;
 114   }
 115   if (Facs->XFirmwareWakingVector != 0) {
 116     if ((Facs->Version == EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_VERSION) &&
 117         ((Facs->Flags & EFI_ACPI_4_0_64BIT_WAKE_SUPPORTED_F) != 0) &&
 118         ((Facs->Flags & EFI_ACPI_4_0_OSPM_64BIT_WAKE__F) != 0)) {
 119       // Both BIOS and OS wants 64bit vector
 120       if (FeaturePcdGet (PcdDxeIplSwitchToLongMode)) {
 121         return TRUE;
 122       }
 123     }
 124   }
 125   return FALSE;
 126 }
 127
 128 /**
 129   Set a IDT entry for interrupt vector 3 for debug purpose.
 130
 131   @param  AcpiS3Context  a pointer to a structure of ACPI_S3_CONTEXT
 132
 133 **/
 134 VOID
 135 SetIdtEntry (
 136   IN ACPI_S3_CONTEXT     *AcpiS3Context
 137   )
 138 {
 139   IA32_IDT_GATE_DESCRIPTOR                      *IdtEntry;
 140   IA32_DESCRIPTOR                               *IdtDescriptor;
 141   UINTN                                         S3DebugBuffer;
 142   EFI_STATUS                                    Status;
 143
 144   //
 145   // Restore IDT for debug
 146   //
 147   IdtDescriptor = (IA32_DESCRIPTOR *) (UINTN) (AcpiS3Context->IdtrProfile);
 148   AsmWriteIdtr (IdtDescriptor);
 149
 150   //
 151   // Setup the default CPU exception handlers
 152   //
 153   Status = InitializeCpuExceptionHandlers (NULL);
 154   ASSERT_EFI_ERROR (Status);
 155
 156   DEBUG_CODE (
 157     //
 158     // Update IDT entry INT3 if the instruction is valid in it
 159     //
 160     S3DebugBuffer = (UINTN) (AcpiS3Context->S3DebugBufferAddress);
 161     if (*(UINTN *)S3DebugBuffer != (UINTN) -1) {
 162       IdtEntry = (IA32_IDT_GATE_DESCRIPTOR *)(IdtDescriptor->Base + (3 * sizeof (IA32_IDT_GATE_DESCRIPTOR)));
 163       IdtEntry->Bits.OffsetLow      = (UINT16)S3DebugBuffer;
 164       IdtEntry->Bits.Selector       = (UINT16)AsmReadCs ();
 165       IdtEntry->Bits.Reserved_0     = 0;
 166       IdtEntry->Bits.GateType       = IA32_IDT_GATE_TYPE_INTERRUPT_32;
 167       IdtEntry->Bits.OffsetHigh     = (UINT16)(S3DebugBuffer >> 16);
 168       IdtEntry->Bits.OffsetUpper    = (UINT32)(S3DebugBuffer >> 32);
 169       IdtEntry->Bits.Reserved_1     = 0;
 170     }
 171   );
 172
 173   //
 174   // If both BIOS and OS wants long mode waking vector,
 175   // S3ResumePei should have established 1:1 Virtual to Physical identity mapping page table,
 176   // no need to hook page fault handler.
 177   //
 178   if (!IsLongModeWakingVector (AcpiS3Context)) {
 179     IdtEntry = (IA32_IDT_GATE_DESCRIPTOR *)(IdtDescriptor->Base + (14 * sizeof (IA32_IDT_GATE_DESCRIPTOR)));
 180     HookPageFaultHandler (IdtEntry);
 181   }
 182 }
 183
 184 /**
 185   Acquire page for page fault.
 186
 187   @param[in, out] Uplink        Pointer to up page table entry.
 188
 189 **/
 190 VOID
 191 AcquirePage (
 192   IN OUT UINT64                 *Uplink
 193   )
 194 {
 195   UINTN             Address;
 196
 197   Address = mPageFaultBuffer + EFI_PAGES_TO_SIZE (mPageFaultIndex);
 198   ZeroMem ((VOID *) Address, EFI_PAGES_TO_SIZE (1));
 199
 200   //
 201   // Cut the previous uplink if it exists and wasn't overwritten.
 202   //
 203   if ((mPageFaultUplink[mPageFaultIndex] != NULL) && ((*mPageFaultUplink[mPageFaultIndex] & mPhyMask) == Address)) {
 204     *mPageFaultUplink[mPageFaultIndex] = 0;
 205   }
 206
 207   //
 208   // Link & Record the current uplink.
 209   //
 210   *Uplink = Address | IA32_PG_P | IA32_PG_RW;
 211   mPageFaultUplink[mPageFaultIndex] = Uplink;
 212
 213   mPageFaultIndex = (mPageFaultIndex + 1) % EXTRA_PAGE_TABLE_PAGES;
 214 }
 215
 216 /**
 217   The page fault handler that on-demand read >4G memory/MMIO.
 218
 219   @retval TRUE     The page fault is correctly handled.
 220   @retval FALSE    The page fault is not handled and is passed through to original handler.
 221
 222 **/
 223 BOOLEAN
 224 EFIAPI
 225 PageFaultHandler (
 226   VOID
 227   )
 228 {
 229   UINT64         *PageTable;
 230   UINT64         PFAddress;
 231   UINTN          PTIndex;
 232
 233   PFAddress = AsmReadCr2 ();
 234   DEBUG ((EFI_D_ERROR, "BootScript - PageFaultHandler: Cr2 - %lx\n", PFAddress));
 235
 236   if (PFAddress >= mPhyMask + SIZE_4KB) {
 237     return FALSE;
 238   }
 239   PFAddress &= mPhyMask;
 240
 241   PageTable = (UINT64*)(UINTN)(AsmReadCr3 () & mPhyMask);
 242
 243   PTIndex = BitFieldRead64 (PFAddress, 39, 47);
 244   // PML4E
 245   if ((PageTable[PTIndex] & IA32_PG_P) == 0) {
 246     AcquirePage (&PageTable[PTIndex]);
 247   }
 248   PageTable = (UINT64*)(UINTN)(PageTable[PTIndex] & mPhyMask);
 249   PTIndex = BitFieldRead64 (PFAddress, 30, 38);
 250   // PDPTE
 251   if (mPage1GSupport) {
 252     PageTable[PTIndex] = (PFAddress & ~((1ull << 30) - 1)) | IA32_PG_P | IA32_PG_RW | IA32_PG_PS;
 253   } else {
 254     if ((PageTable[PTIndex] & IA32_PG_P) == 0) {
 255       AcquirePage (&PageTable[PTIndex]);
 256     }
 257     PageTable = (UINT64*)(UINTN)(PageTable[PTIndex] & mPhyMask);
 258     PTIndex = BitFieldRead64 (PFAddress, 21, 29);
 259     // PD
 260     PageTable[PTIndex] = (PFAddress & ~((1ull << 21) - 1)) | IA32_PG_P | IA32_PG_RW | IA32_PG_PS;
 261   }
 262
 263   return TRUE;
 264 }