--- /dev/null
+/** @file\r
+ This is the implementation to save ACPI S3 Context.\r
+\r
+Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>\r
+\r
+This program and the accompanying materials\r
+are licensed and made available under the terms and conditions\r
+of the BSD License which accompanies this distribution. The\r
+full text of the license may be found at\r
+http://opensource.org/licenses/bsd-license.php\r
+\r
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
+\r
+**/\r
+\r
+#include <PiDxe.h>\r
+#include <Library/BaseLib.h>\r
+#include <Library/BaseMemoryLib.h>\r
+#include <Library/UefiBootServicesTableLib.h>\r
+#include <Library/HobLib.h>\r
+#include <Library/LockBoxLib.h>\r
+#include <Library/PcdLib.h>\r
+#include <Library/DebugLib.h>\r
+#include <Guid/AcpiS3Context.h>\r
+#include <Guid/Acpi.h>\r
+#include <IndustryStandard/Acpi.h>\r
+#include <Protocol/LockBox.h>\r
+\r
+//\r
+// 8 extra pages for PF handler.\r
+//\r
+#define EXTRA_PAGE_TABLE_PAGES 8\r
+\r
+EFI_GUID mAcpiS3IdtrProfileGuid = {\r
+ 0xdea652b0, 0xd587, 0x4c54, { 0xb5, 0xb4, 0xc6, 0x82, 0xe7, 0xa0, 0xaa, 0x3d }\r
+};\r
+\r
+/**\r
+ Allocate memory below 4G memory address.\r
+\r
+ This function allocates memory below 4G memory address.\r
+\r
+ @param MemoryType Memory type of memory to allocate.\r
+ @param Size Size of memory to allocate.\r
+ \r
+ @return Allocated address for output.\r
+\r
+**/\r
+VOID*\r
+AllocateMemoryBelow4G (\r
+ IN EFI_MEMORY_TYPE MemoryType,\r
+ IN UINTN Size\r
+ )\r
+{\r
+ UINTN Pages;\r
+ EFI_PHYSICAL_ADDRESS Address;\r
+ EFI_STATUS Status;\r
+ VOID* Buffer;\r
+\r
+ Pages = EFI_SIZE_TO_PAGES (Size);\r
+ Address = 0xffffffff;\r
+\r
+ Status = gBS->AllocatePages (\r
+ AllocateMaxAddress,\r
+ MemoryType,\r
+ Pages,\r
+ &Address\r
+ );\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ Buffer = (VOID *) (UINTN) Address;\r
+ ZeroMem (Buffer, Size);\r
+\r
+ return Buffer;\r
+}\r
+\r
+/**\r
+\r
+ This function scan ACPI table in RSDT.\r
+\r
+ @param Rsdt ACPI RSDT\r
+ @param Signature ACPI table signature\r
+\r
+ @return ACPI table\r
+\r
+**/\r
+VOID *\r
+ScanTableInRSDT (\r
+ IN EFI_ACPI_DESCRIPTION_HEADER *Rsdt,\r
+ IN UINT32 Signature\r
+ )\r
+{\r
+ UINTN Index;\r
+ UINT32 EntryCount;\r
+ UINT32 *EntryPtr;\r
+ EFI_ACPI_DESCRIPTION_HEADER *Table;\r
+\r
+ if (Rsdt == NULL) {\r
+ return NULL;\r
+ }\r
+\r
+ EntryCount = (Rsdt->Length - sizeof (EFI_ACPI_DESCRIPTION_HEADER)) / sizeof(UINT32);\r
+ \r
+ EntryPtr = (UINT32 *)(Rsdt + 1);\r
+ for (Index = 0; Index < EntryCount; Index ++, EntryPtr ++) {\r
+ Table = (EFI_ACPI_DESCRIPTION_HEADER *)((UINTN)(*EntryPtr));\r
+ if (Table->Signature == Signature) {\r
+ return Table;\r
+ }\r
+ }\r
+ \r
+ return NULL;\r
+}\r
+\r
+/**\r
+\r
+ This function scan ACPI table in XSDT.\r
+\r
+ @param Xsdt ACPI XSDT\r
+ @param Signature ACPI table signature\r
+\r
+ @return ACPI table\r
+\r
+**/\r
+VOID *\r
+ScanTableInXSDT (\r
+ IN EFI_ACPI_DESCRIPTION_HEADER *Xsdt,\r
+ IN UINT32 Signature\r
+ )\r
+{\r
+ UINTN Index;\r
+ UINT32 EntryCount;\r
+ UINT64 EntryPtr;\r
+ UINTN BasePtr;\r
+ EFI_ACPI_DESCRIPTION_HEADER *Table;\r
+\r
+ if (Xsdt == NULL) {\r
+ return NULL;\r
+ }\r
+\r
+ EntryCount = (Xsdt->Length - sizeof (EFI_ACPI_DESCRIPTION_HEADER)) / sizeof(UINT64);\r
+ \r
+ BasePtr = (UINTN)(Xsdt + 1);\r
+ for (Index = 0; Index < EntryCount; Index ++) {\r
+ CopyMem (&EntryPtr, (VOID *)(BasePtr + Index * sizeof(UINT64)), sizeof(UINT64));\r
+ Table = (EFI_ACPI_DESCRIPTION_HEADER *)((UINTN)(EntryPtr));\r
+ if (Table->Signature == Signature) {\r
+ return Table;\r
+ }\r
+ }\r
+ \r
+ return NULL;\r
+}\r
+\r
+/**\r
+ To find Facs in FADT.\r
+\r
+ @param Fadt FADT table pointer\r
+ \r
+ @return Facs table pointer.\r
+**/\r
+EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *\r
+FindAcpiFacsFromFadt (\r
+ IN EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *Fadt\r
+ )\r
+{\r
+ EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *Facs;\r
+ UINT64 Data64;\r
+\r
+ if (Fadt == NULL) {\r
+ return NULL;\r
+ }\r
+\r
+ if (Fadt->Header.Revision < EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_REVISION) {\r
+ Facs = (EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *)(UINTN)Fadt->FirmwareCtrl;\r
+ } else {\r
+ if (Fadt->FirmwareCtrl != 0) {\r
+ Facs = (EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *)(UINTN)Fadt->FirmwareCtrl;\r
+ } else {\r
+ CopyMem (&Data64, &Fadt->XFirmwareCtrl, sizeof(UINT64));\r
+ Facs = (EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *)(UINTN)Data64;\r
+ }\r
+ }\r
+ return Facs;\r
+}\r
+\r
+/**\r
+ To find Facs in Acpi tables.\r
+ \r
+ To find Firmware ACPI control strutcure in Acpi Tables since the S3 waking vector is stored \r
+ in the table.\r
+\r
+ @param AcpiTableGuid The guid used to find ACPI table in UEFI ConfigurationTable.\r
+ \r
+ @return Facs table pointer.\r
+**/\r
+EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *\r
+FindAcpiFacsTableByAcpiGuid (\r
+ IN EFI_GUID *AcpiTableGuid\r
+ )\r
+{\r
+ EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER *Rsdp;\r
+ EFI_ACPI_DESCRIPTION_HEADER *Rsdt;\r
+ EFI_ACPI_DESCRIPTION_HEADER *Xsdt;\r
+ EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *Fadt;\r
+ EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *Facs;\r
+ UINTN Index;\r
+\r
+ Rsdp = NULL;\r
+ //\r
+ // found ACPI table RSD_PTR from system table\r
+ //\r
+ for (Index = 0; Index < gST->NumberOfTableEntries; Index++) {\r
+ if (CompareGuid (&(gST->ConfigurationTable[Index].VendorGuid), AcpiTableGuid)) {\r
+ //\r
+ // A match was found.\r
+ //\r
+ Rsdp = gST->ConfigurationTable[Index].VendorTable;\r
+ break;\r
+ }\r
+ }\r
+\r
+ if (Rsdp == NULL) {\r
+ return NULL;\r
+ }\r
+\r
+ //\r
+ // Search XSDT\r
+ //\r
+ if (Rsdp->Revision >= EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER_REVISION) {\r
+ Xsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN) Rsdp->XsdtAddress;\r
+ Fadt = ScanTableInXSDT (Xsdt, EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE);\r
+ if (Fadt != NULL) {\r
+ Facs = FindAcpiFacsFromFadt (Fadt);\r
+ if (Facs != NULL) {\r
+ return Facs;\r
+ }\r
+ }\r
+ }\r
+\r
+ //\r
+ // Search RSDT\r
+ //\r
+ Rsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN) Rsdp->RsdtAddress;\r
+ Fadt = ScanTableInRSDT (Rsdt, EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE);\r
+ if (Fadt != NULL) {\r
+ Facs = FindAcpiFacsFromFadt (Fadt);\r
+ if (Facs != NULL) {\r
+ return Facs;\r
+ }\r
+ }\r
+\r
+ return NULL;\r
+}\r
+\r
+/**\r
+ To find Facs in Acpi tables.\r
+ \r
+ To find Firmware ACPI control strutcure in Acpi Tables since the S3 waking vector is stored \r
+ in the table.\r
+ \r
+ @return Facs table pointer.\r
+**/\r
+EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *\r
+FindAcpiFacsTable (\r
+ VOID\r
+ )\r
+{\r
+ EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *Facs;\r
+\r
+ Facs = FindAcpiFacsTableByAcpiGuid (&gEfiAcpi20TableGuid);\r
+ if (Facs != NULL) {\r
+ return Facs;\r
+ }\r
+\r
+ return FindAcpiFacsTableByAcpiGuid (&gEfiAcpi10TableGuid);\r
+}\r
+\r
+/**\r
+ The function will check if long mode waking vector is supported.\r
+\r
+ @param[in] Facs Pointer to FACS table.\r
+\r
+ @retval TRUE Long mode waking vector is supported.\r
+ @retval FALSE Long mode waking vector is not supported.\r
+\r
+**/\r
+BOOLEAN\r
+IsLongModeWakingVectorSupport (\r
+ IN EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *Facs\r
+ )\r
+{\r
+ if ((Facs == NULL) ||\r
+ (Facs->Signature != EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE) ) {\r
+ //\r
+ // Something wrong with FACS.\r
+ //\r
+ return FALSE;\r
+ }\r
+ if ((Facs->Version == EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_VERSION) &&\r
+ ((Facs->Flags & EFI_ACPI_4_0_64BIT_WAKE_SUPPORTED_F) != 0)) {\r
+ //\r
+ // BIOS supports 64bit waking vector.\r
+ //\r
+ if (FeaturePcdGet (PcdDxeIplSwitchToLongMode)) {\r
+ return TRUE;\r
+ }\r
+ }\r
+ return FALSE;\r
+}\r
+\r
+/**\r
+ Allocates page table buffer.\r
+\r
+ @param[in] LongModeWakingVectorSupport Support long mode waking vector or not.\r
+\r
+ If BootScriptExector driver will run in 64-bit mode, this function will establish the 1:1 \r
+ virtual to physical mapping page table when long mode waking vector is supported, otherwise\r
+ create 4G page table when long mode waking vector is not supported and let PF handler to\r
+ handle > 4G request.\r
+ If BootScriptExector driver will not run in 64-bit mode, this function will do nothing. \r
+ \r
+ @return Page table base address. \r
+\r
+**/\r
+EFI_PHYSICAL_ADDRESS\r
+S3AllocatePageTablesBuffer (\r
+ IN BOOLEAN LongModeWakingVectorSupport\r
+ )\r
+{ \r
+ if (FeaturePcdGet (PcdDxeIplSwitchToLongMode)) {\r
+ UINTN ExtraPageTablePages;\r
+ UINT32 RegEax;\r
+ UINT32 RegEdx;\r
+ UINT8 PhysicalAddressBits;\r
+ UINT32 NumberOfPml4EntriesNeeded;\r
+ UINT32 NumberOfPdpEntriesNeeded;\r
+ EFI_PHYSICAL_ADDRESS S3NvsPageTableAddress;\r
+ UINTN TotalPageTableSize;\r
+ VOID *Hob;\r
+ BOOLEAN Page1GSupport;\r
+\r
+ Page1GSupport = FALSE;\r
+ if (PcdGetBool(PcdUse1GPageTable)) {\r
+ AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);\r
+ if (RegEax >= 0x80000001) {\r
+ AsmCpuid (0x80000001, NULL, NULL, NULL, &RegEdx);\r
+ if ((RegEdx & BIT26) != 0) {\r
+ Page1GSupport = TRUE;\r
+ }\r
+ }\r
+ }\r
+\r
+ //\r
+ // Get physical address bits supported.\r
+ //\r
+ Hob = GetFirstHob (EFI_HOB_TYPE_CPU);\r
+ if (Hob != NULL) {\r
+ PhysicalAddressBits = ((EFI_HOB_CPU *) Hob)->SizeOfMemorySpace;\r
+ } else {\r
+ AsmCpuid (0x80000000, &RegEax, NULL, NULL, NULL);\r
+ if (RegEax >= 0x80000008) {\r
+ AsmCpuid (0x80000008, &RegEax, NULL, NULL, NULL);\r
+ PhysicalAddressBits = (UINT8) RegEax;\r
+ } else {\r
+ PhysicalAddressBits = 36;\r
+ }\r
+ }\r
+\r
+ //\r
+ // IA-32e paging translates 48-bit linear addresses to 52-bit physical addresses.\r
+ //\r
+ ASSERT (PhysicalAddressBits <= 52);\r
+ if (PhysicalAddressBits > 48) {\r
+ PhysicalAddressBits = 48;\r
+ }\r
+\r
+ ExtraPageTablePages = 0;\r
+ if (!LongModeWakingVectorSupport) {\r
+ //\r
+ // Create 4G page table when BIOS does not support long mode waking vector,\r
+ // and let PF handler to handle > 4G request.\r
+ //\r
+ PhysicalAddressBits = 32;\r
+ ExtraPageTablePages = EXTRA_PAGE_TABLE_PAGES;\r
+ }\r
+\r
+ //\r
+ // Calculate the table entries needed.\r
+ //\r
+ if (PhysicalAddressBits <= 39 ) {\r
+ NumberOfPml4EntriesNeeded = 1;\r
+ NumberOfPdpEntriesNeeded = (UINT32)LShiftU64 (1, (PhysicalAddressBits - 30));\r
+ } else {\r
+ NumberOfPml4EntriesNeeded = (UINT32)LShiftU64 (1, (PhysicalAddressBits - 39));\r
+ NumberOfPdpEntriesNeeded = 512;\r
+ }\r
+\r
+ //\r
+ // We need calculate whole page size then allocate once, because S3 restore page table does not know each page in Nvs.\r
+ //\r
+ if (!Page1GSupport) {\r
+ TotalPageTableSize = (UINTN)(1 + NumberOfPml4EntriesNeeded + NumberOfPml4EntriesNeeded * NumberOfPdpEntriesNeeded);\r
+ } else {\r
+ TotalPageTableSize = (UINTN)(1 + NumberOfPml4EntriesNeeded);\r
+ }\r
+\r
+ TotalPageTableSize += ExtraPageTablePages;\r
+ DEBUG ((EFI_D_ERROR, "AcpiS3ContextSave TotalPageTableSize - 0x%x pages\n", TotalPageTableSize));\r
+\r
+ //\r
+ // By architecture only one PageMapLevel4 exists - so lets allocate storage for it.\r
+ //\r
+ S3NvsPageTableAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)AllocateMemoryBelow4G (EfiReservedMemoryType, EFI_PAGES_TO_SIZE(TotalPageTableSize));\r
+ ASSERT (S3NvsPageTableAddress != 0);\r
+ return S3NvsPageTableAddress;\r
+ } else {\r
+ //\r
+ // If DXE is running 32-bit mode, no need to establish page table.\r
+ //\r
+ return (EFI_PHYSICAL_ADDRESS) 0; \r
+ }\r
+}\r
+\r
+/**\r
+ Callback function executed when the EndOfDxe event group is signaled.\r
+\r
+ @param[in] Event Event whose notification function is being invoked.\r
+ @param[in] Context The pointer to the notification function's context, which\r
+ is implementation-dependent.\r
+**/\r
+VOID\r
+EFIAPI\r
+AcpiS3ContextSaveOnEndOfDxe (\r
+ IN EFI_EVENT Event,\r
+ IN VOID *Context\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ EFI_PHYSICAL_ADDRESS AcpiS3ContextBuffer;\r
+ ACPI_S3_CONTEXT *AcpiS3Context;\r
+ IA32_DESCRIPTOR *Idtr;\r
+ IA32_IDT_GATE_DESCRIPTOR *IdtGate;\r
+ EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *Facs;\r
+ VOID *Interface;\r
+\r
+ DEBUG ((EFI_D_INFO, "AcpiS3ContextSave!\n"));\r
+\r
+ Status = gBS->LocateProtocol (&gEfiLockBoxProtocolGuid, NULL, &Interface);\r
+ if (EFI_ERROR (Status)) {\r
+ DEBUG ((EFI_D_INFO | EFI_D_WARN, "ACPI S3 context can't be saved without LockBox!\n"));\r
+ goto Done;\r
+ }\r
+\r
+ AcpiS3Context = AllocateMemoryBelow4G (EfiReservedMemoryType, sizeof(*AcpiS3Context));\r
+ ASSERT (AcpiS3Context != NULL);\r
+ AcpiS3ContextBuffer = (EFI_PHYSICAL_ADDRESS)(UINTN)AcpiS3Context;\r
+\r
+ //\r
+ // Get ACPI Table because we will save its position to variable\r
+ //\r
+ Facs = (EFI_ACPI_4_0_FIRMWARE_ACPI_CONTROL_STRUCTURE *) FindAcpiFacsTable ();\r
+ AcpiS3Context->AcpiFacsTable = (EFI_PHYSICAL_ADDRESS) (UINTN) Facs;\r
+ ASSERT (AcpiS3Context->AcpiFacsTable != 0);\r
+\r
+ IdtGate = AllocateMemoryBelow4G (EfiReservedMemoryType, sizeof(IA32_IDT_GATE_DESCRIPTOR) * 0x100 + sizeof(IA32_DESCRIPTOR));\r
+ Idtr = (IA32_DESCRIPTOR *)(IdtGate + 0x100);\r
+ Idtr->Base = (UINTN)IdtGate;\r
+ Idtr->Limit = (UINT16)(sizeof(IA32_IDT_GATE_DESCRIPTOR) * 0x100 - 1);\r
+ AcpiS3Context->IdtrProfile = (EFI_PHYSICAL_ADDRESS)(UINTN)Idtr;\r
+\r
+ Status = SaveLockBox (\r
+ &mAcpiS3IdtrProfileGuid,\r
+ (VOID *)(UINTN)Idtr,\r
+ (UINTN)sizeof(IA32_DESCRIPTOR)\r
+ );\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ Status = SetLockBoxAttributes (&mAcpiS3IdtrProfileGuid, LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE);\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ //\r
+ // Allocate page table\r
+ //\r
+ AcpiS3Context->S3NvsPageTableAddress = S3AllocatePageTablesBuffer (IsLongModeWakingVectorSupport (Facs));\r
+\r
+ //\r
+ // Allocate stack\r
+ //\r
+ AcpiS3Context->BootScriptStackSize = PcdGet32 (PcdS3BootScriptStackSize);\r
+ AcpiS3Context->BootScriptStackBase = (EFI_PHYSICAL_ADDRESS)(UINTN)AllocateMemoryBelow4G (EfiReservedMemoryType, PcdGet32 (PcdS3BootScriptStackSize));\r
+ ASSERT (AcpiS3Context->BootScriptStackBase != 0);\r
+\r
+ //\r
+ // Allocate a code buffer < 4G for S3 debug to load external code, set invalid code instructions in it.\r
+ //\r
+ AcpiS3Context->S3DebugBufferAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)AllocateMemoryBelow4G (EfiReservedMemoryType, EFI_PAGE_SIZE);\r
+ SetMem ((VOID *)(UINTN)AcpiS3Context->S3DebugBufferAddress, EFI_PAGE_SIZE, 0xff);\r
+\r
+ DEBUG((EFI_D_INFO, "AcpiS3Context: AcpiFacsTable is 0x%8x\n", AcpiS3Context->AcpiFacsTable));\r
+ DEBUG((EFI_D_INFO, "AcpiS3Context: IdtrProfile is 0x%8x\n", AcpiS3Context->IdtrProfile));\r
+ DEBUG((EFI_D_INFO, "AcpiS3Context: S3NvsPageTableAddress is 0x%8x\n", AcpiS3Context->S3NvsPageTableAddress));\r
+ DEBUG((EFI_D_INFO, "AcpiS3Context: S3DebugBufferAddress is 0x%8x\n", AcpiS3Context->S3DebugBufferAddress));\r
+ DEBUG((EFI_D_INFO, "AcpiS3Context: BootScriptStackBase is 0x%8x\n", AcpiS3Context->BootScriptStackBase));\r
+ DEBUG((EFI_D_INFO, "AcpiS3Context: BootScriptStackSize is 0x%8x\n", AcpiS3Context->BootScriptStackSize));\r
+\r
+ Status = SaveLockBox (\r
+ &gEfiAcpiVariableGuid,\r
+ &AcpiS3ContextBuffer,\r
+ sizeof(AcpiS3ContextBuffer)\r
+ );\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ Status = SaveLockBox (\r
+ &gEfiAcpiS3ContextGuid,\r
+ (VOID *)(UINTN)AcpiS3Context,\r
+ (UINTN)sizeof(*AcpiS3Context)\r
+ );\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ Status = SetLockBoxAttributes (&gEfiAcpiS3ContextGuid, LOCK_BOX_ATTRIBUTE_RESTORE_IN_PLACE);\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+Done:\r
+ //\r
+ // Close the event, deregistering the callback and freeing resources.\r
+ //\r
+ Status = gBS->CloseEvent (Event);\r
+ ASSERT_EFI_ERROR (Status);\r
+}\r
+\r
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