+++ /dev/null
-/** @file\r
- Call into 16-bit BIOS code, Use AsmThunk16 function of BaseLib.\r
-\r
-Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
-\r
-SPDX-License-Identifier: BSD-2-Clause-Patent\r
-\r
-**/\r
-\r
-#include "LegacyBiosInterface.h"\r
-\r
-THUNK_CONTEXT mThunkContext;\r
-\r
-/**\r
- Sets the counter value for Timer #0 in a legacy 8254 timer.\r
-\r
- @param Count - The 16-bit counter value to program into Timer #0 of the legacy 8254 timer.\r
-\r
-**/\r
-VOID\r
-SetPitCount (\r
- IN UINT16 Count\r
- )\r
-{\r
- IoWrite8 (TIMER_CONTROL_PORT, TIMER0_CONTROL_WORD);\r
- IoWrite8 (TIMER0_COUNT_PORT, (UINT8) (Count & 0xFF));\r
- IoWrite8 (TIMER0_COUNT_PORT, (UINT8) ((Count>>8) & 0xFF));\r
-}\r
-\r
-/**\r
- Thunk to 16-bit real mode and execute a software interrupt with a vector\r
- of BiosInt. Regs will contain the 16-bit register context on entry and\r
- exit.\r
-\r
- @param This Protocol instance pointer.\r
- @param BiosInt Processor interrupt vector to invoke\r
- @param Regs Register contexted passed into (and returned) from thunk to\r
- 16-bit mode\r
-\r
- @retval FALSE Thunk completed, and there were no BIOS errors in the target code.\r
- See Regs for status.\r
- @retval TRUE There was a BIOS erro in the target code.\r
-\r
-**/\r
-BOOLEAN\r
-EFIAPI\r
-LegacyBiosInt86 (\r
- IN EFI_LEGACY_BIOS_PROTOCOL *This,\r
- IN UINT8 BiosInt,\r
- IN EFI_IA32_REGISTER_SET *Regs\r
- )\r
-{\r
- UINT16 Segment;\r
- UINT16 Offset;\r
-\r
- Regs->X.Flags.Reserved1 = 1;\r
- Regs->X.Flags.Reserved2 = 0;\r
- Regs->X.Flags.Reserved3 = 0;\r
- Regs->X.Flags.Reserved4 = 0;\r
- Regs->X.Flags.IOPL = 3;\r
- Regs->X.Flags.NT = 0;\r
- Regs->X.Flags.IF = 0;\r
- Regs->X.Flags.TF = 0;\r
- Regs->X.Flags.CF = 0;\r
- //\r
- // The base address of legacy interrupt vector table is 0.\r
- // We use this base address to get the legacy interrupt handler.\r
- //\r
- ACCESS_PAGE0_CODE (\r
- Segment = (UINT16)(((UINT32 *)0)[BiosInt] >> 16);\r
- Offset = (UINT16)((UINT32 *)0)[BiosInt];\r
- );\r
-\r
- return InternalLegacyBiosFarCall (\r
- This,\r
- Segment,\r
- Offset,\r
- Regs,\r
- &Regs->X.Flags,\r
- sizeof (Regs->X.Flags)\r
- );\r
-}\r
-\r
-/**\r
- Thunk to 16-bit real mode and call Segment:Offset. Regs will contain the\r
- 16-bit register context on entry and exit. Arguments can be passed on\r
- the Stack argument\r
-\r
- @param This Protocol instance pointer.\r
- @param Segment Segemnt of 16-bit mode call\r
- @param Offset Offset of 16-bit mdoe call\r
- @param Regs Register contexted passed into (and returned) from\r
- thunk to 16-bit mode\r
- @param Stack Caller allocated stack used to pass arguments\r
- @param StackSize Size of Stack in bytes\r
-\r
- @retval FALSE Thunk completed, and there were no BIOS errors in\r
- the target code. See Regs for status.\r
- @retval TRUE There was a BIOS erro in the target code.\r
-\r
-**/\r
-BOOLEAN\r
-EFIAPI\r
-LegacyBiosFarCall86 (\r
- IN EFI_LEGACY_BIOS_PROTOCOL *This,\r
- IN UINT16 Segment,\r
- IN UINT16 Offset,\r
- IN EFI_IA32_REGISTER_SET *Regs,\r
- IN VOID *Stack,\r
- IN UINTN StackSize\r
- )\r
-{\r
- Regs->X.Flags.Reserved1 = 1;\r
- Regs->X.Flags.Reserved2 = 0;\r
- Regs->X.Flags.Reserved3 = 0;\r
- Regs->X.Flags.Reserved4 = 0;\r
- Regs->X.Flags.IOPL = 3;\r
- Regs->X.Flags.NT = 0;\r
- Regs->X.Flags.IF = 1;\r
- Regs->X.Flags.TF = 0;\r
- Regs->X.Flags.CF = 0;\r
-\r
- return InternalLegacyBiosFarCall (This, Segment, Offset, Regs, Stack, StackSize);\r
-}\r
-\r
-/**\r
- Provide NULL interrupt handler which is used to check\r
- if there is more than one HW interrupt registers with the CPU AP.\r
-\r
- @param InterruptType - The type of interrupt that occured\r
- @param SystemContext - A pointer to the system context when the interrupt occured\r
-\r
-**/\r
-VOID\r
-EFIAPI\r
-LegacyBiosNullInterruptHandler (\r
- IN EFI_EXCEPTION_TYPE InterruptType,\r
- IN EFI_SYSTEM_CONTEXT SystemContext\r
- )\r
-{\r
-}\r
-\r
-/**\r
- Thunk to 16-bit real mode and call Segment:Offset. Regs will contain the\r
- 16-bit register context on entry and exit. Arguments can be passed on\r
- the Stack argument\r
-\r
- @param This Protocol instance pointer.\r
- @param Segment Segemnt of 16-bit mode call\r
- @param Offset Offset of 16-bit mdoe call\r
- @param Regs Register contexted passed into (and returned) from thunk to\r
- 16-bit mode\r
- @param Stack Caller allocated stack used to pass arguments\r
- @param StackSize Size of Stack in bytes\r
-\r
- @retval FALSE Thunk completed, and there were no BIOS errors in the target code.\r
- See Regs for status.\r
- @retval TRUE There was a BIOS erro in the target code.\r
-\r
-**/\r
-BOOLEAN\r
-EFIAPI\r
-InternalLegacyBiosFarCall (\r
- IN EFI_LEGACY_BIOS_PROTOCOL *This,\r
- IN UINT16 Segment,\r
- IN UINT16 Offset,\r
- IN EFI_IA32_REGISTER_SET *Regs,\r
- IN VOID *Stack,\r
- IN UINTN StackSize\r
- )\r
-{\r
- UINTN Status;\r
- LEGACY_BIOS_INSTANCE *Private;\r
- UINT16 *Stack16;\r
- EFI_TPL OriginalTpl;\r
- IA32_REGISTER_SET ThunkRegSet;\r
- BOOLEAN InterruptState;\r
- UINT64 TimerPeriod;\r
-\r
- Private = LEGACY_BIOS_INSTANCE_FROM_THIS (This);\r
-\r
- ZeroMem (&ThunkRegSet, sizeof (ThunkRegSet));\r
- ThunkRegSet.X.DI = Regs->X.DI;\r
- ThunkRegSet.X.SI = Regs->X.SI;\r
- ThunkRegSet.X.BP = Regs->X.BP;\r
- ThunkRegSet.X.BX = Regs->X.BX;\r
- ThunkRegSet.X.DX = Regs->X.DX;\r
- //\r
- // Sometimes, ECX is used to pass in 32 bit data. For example, INT 1Ah, AX = B10Dh is\r
- // "PCI BIOS v2.0c + Write Configuration DWORD" and ECX has the dword to write.\r
- //\r
- ThunkRegSet.E.ECX = Regs->E.ECX;\r
- ThunkRegSet.X.AX = Regs->X.AX;\r
- ThunkRegSet.E.DS = Regs->X.DS;\r
- ThunkRegSet.E.ES = Regs->X.ES;\r
-\r
- CopyMem (&(ThunkRegSet.E.EFLAGS.UintN), &(Regs->X.Flags), sizeof (Regs->X.Flags));\r
-\r
- //\r
- // Clear the error flag; thunk code may set it. Stack16 should be the high address\r
- // Make Statk16 address the low 16 bit must be not zero.\r
- //\r
- Stack16 = (UINT16 *)((UINT8 *) mThunkContext.RealModeBuffer + mThunkContext.RealModeBufferSize - sizeof (UINT16));\r
-\r
- //\r
- // Save current rate of DXE Timer\r
- //\r
- Private->Timer->GetTimerPeriod (Private->Timer, &TimerPeriod);\r
-\r
- //\r
- // Disable DXE Timer while executing in real mode\r
- //\r
- Private->Timer->SetTimerPeriod (Private->Timer, 0);\r
-\r
- //\r
- // Save and disable interrupt of debug timer\r
- //\r
- InterruptState = SaveAndSetDebugTimerInterrupt (FALSE);\r
-\r
- //\r
- // The call to Legacy16 is a critical section to EFI\r
- //\r
- OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
-\r
- //\r
- // Check to see if there is more than one HW interrupt registers with the CPU AP.\r
- // If there is, then ASSERT() since that is not compatible with the CSM because\r
- // interupts other than the Timer interrupt that was disabled above can not be\r
- // handled properly from real mode.\r
- //\r
- DEBUG_CODE (\r
- UINTN Vector;\r
- UINTN Count;\r
-\r
- for (Vector = 0x20, Count = 0; Vector < 0x100; Vector++) {\r
- Status = Private->Cpu->RegisterInterruptHandler (Private->Cpu, Vector, LegacyBiosNullInterruptHandler);\r
- if (Status == EFI_ALREADY_STARTED) {\r
- Count++;\r
- }\r
- if (Status == EFI_SUCCESS) {\r
- Private->Cpu->RegisterInterruptHandler (Private->Cpu, Vector, NULL);\r
- }\r
- }\r
- if (Count >= 2) {\r
- DEBUG ((EFI_D_ERROR, "ERROR: More than one HW interrupt active with CSM enabled\n"));\r
- }\r
- ASSERT (Count < 2);\r
- );\r
-\r
- //\r
- // If the Timer AP has enabled the 8254 timer IRQ and the current 8254 timer\r
- // period is less than the CSM required rate of 54.9254, then force the 8254\r
- // PIT counter to 0, which is the CSM required rate of 54.9254 ms\r
- //\r
- if (Private->TimerUses8254 && TimerPeriod < 549254) {\r
- SetPitCount (0);\r
- }\r
-\r
- if (Stack != NULL && StackSize != 0) {\r
- //\r
- // Copy Stack to low memory stack\r
- //\r
- Stack16 -= StackSize / sizeof (UINT16);\r
- CopyMem (Stack16, Stack, StackSize);\r
- }\r
-\r
- ThunkRegSet.E.SS = (UINT16) (((UINTN) Stack16 >> 16) << 12);\r
- ThunkRegSet.E.ESP = (UINT16) (UINTN) Stack16;\r
- ThunkRegSet.E.CS = Segment;\r
- ThunkRegSet.E.Eip = Offset;\r
-\r
- mThunkContext.RealModeState = &ThunkRegSet;\r
-\r
- //\r
- // Set Legacy16 state. 0x08, 0x70 is legacy 8259 vector bases.\r
- //\r
- Status = Private->Legacy8259->SetMode (Private->Legacy8259, Efi8259LegacyMode, NULL, NULL);\r
- ASSERT_EFI_ERROR (Status);\r
-\r
- AsmThunk16 (&mThunkContext);\r
-\r
- if (Stack != NULL && StackSize != 0) {\r
- //\r
- // Copy low memory stack to Stack\r
- //\r
- CopyMem (Stack, Stack16, StackSize);\r
- }\r
-\r
- //\r
- // Restore protected mode interrupt state\r
- //\r
- Status = Private->Legacy8259->SetMode (Private->Legacy8259, Efi8259ProtectedMode, NULL, NULL);\r
- ASSERT_EFI_ERROR (Status);\r
-\r
- mThunkContext.RealModeState = NULL;\r
-\r
- //\r
- // Enable and restore rate of DXE Timer\r
- //\r
- Private->Timer->SetTimerPeriod (Private->Timer, TimerPeriod);\r
-\r
- //\r
- // End critical section\r
- //\r
- gBS->RestoreTPL (OriginalTpl);\r
-\r
- //\r
- // OPROM may allocate EBDA range by itself and change EBDA base and EBDA size.\r
- // Get the current EBDA base address, and compared with pre-allocate minimum\r
- // EBDA base address, if the current EBDA base address is smaller, it indicates\r
- // PcdEbdaReservedMemorySize should be adjusted to larger for more OPROMs.\r
- //\r
- DEBUG_CODE (\r
- {\r
- UINTN EbdaBaseAddress;\r
- UINTN ReservedEbdaBaseAddress;\r
-\r
- ACCESS_PAGE0_CODE (\r
- EbdaBaseAddress = (*(UINT16 *) (UINTN) 0x40E) << 4;\r
- ReservedEbdaBaseAddress = CONVENTIONAL_MEMORY_TOP\r
- - PcdGet32 (PcdEbdaReservedMemorySize);\r
- ASSERT (ReservedEbdaBaseAddress <= EbdaBaseAddress);\r
- );\r
- }\r
- );\r
-\r
- //\r
- // Restore interrupt of debug timer\r
- //\r
- SaveAndSetDebugTimerInterrupt (InterruptState);\r
-\r
- Regs->E.EDI = ThunkRegSet.E.EDI;\r
- Regs->E.ESI = ThunkRegSet.E.ESI;\r
- Regs->E.EBP = ThunkRegSet.E.EBP;\r
- Regs->E.EBX = ThunkRegSet.E.EBX;\r
- Regs->E.EDX = ThunkRegSet.E.EDX;\r
- Regs->E.ECX = ThunkRegSet.E.ECX;\r
- Regs->E.EAX = ThunkRegSet.E.EAX;\r
- Regs->X.SS = ThunkRegSet.E.SS;\r
- Regs->X.CS = ThunkRegSet.E.CS;\r
- Regs->X.DS = ThunkRegSet.E.DS;\r
- Regs->X.ES = ThunkRegSet.E.ES;\r
-\r
- CopyMem (&(Regs->X.Flags), &(ThunkRegSet.E.EFLAGS.UintN), sizeof (Regs->X.Flags));\r
-\r
- return (BOOLEAN) (Regs->X.Flags.CF == 1);\r
-}\r
-\r
-/**\r
- Allocate memory < 1 MB and copy the thunker code into low memory. Se up\r
- all the descriptors.\r
-\r
- @param Private Private context for Legacy BIOS\r
-\r
- @retval EFI_SUCCESS Should only pass.\r
-\r
-**/\r
-EFI_STATUS\r
-LegacyBiosInitializeThunk (\r
- IN LEGACY_BIOS_INSTANCE *Private\r
- )\r
-{\r
- EFI_STATUS Status;\r
- EFI_PHYSICAL_ADDRESS MemoryAddress;\r
- UINT8 TimerVector;\r
-\r
- MemoryAddress = (EFI_PHYSICAL_ADDRESS) (UINTN) Private->IntThunk;\r
-\r
- mThunkContext.RealModeBuffer = (VOID *) (UINTN) (MemoryAddress + ((sizeof (LOW_MEMORY_THUNK) / EFI_PAGE_SIZE) + 1) * EFI_PAGE_SIZE);\r
- mThunkContext.RealModeBufferSize = EFI_PAGE_SIZE;\r
- mThunkContext.ThunkAttributes = THUNK_ATTRIBUTE_BIG_REAL_MODE | THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15;\r
-\r
- AsmPrepareThunk16 (&mThunkContext);\r
-\r
- //\r
- // Get the interrupt vector number corresponding to IRQ0 from the 8259 driver\r
- //\r
- TimerVector = 0;\r
- Status = Private->Legacy8259->GetVector (Private->Legacy8259, Efi8259Irq0, &TimerVector);\r
- ASSERT_EFI_ERROR (Status);\r
-\r
- //\r
- // Check to see if the Timer AP has hooked the IRQ0 from the 8254 PIT\r
- //\r
- Status = Private->Cpu->RegisterInterruptHandler (\r
- Private->Cpu,\r
- TimerVector,\r
- LegacyBiosNullInterruptHandler\r
- );\r
- if (Status == EFI_SUCCESS) {\r
- //\r
- // If the Timer AP has not enabled the 8254 timer IRQ, then force the 8254 PIT\r
- // counter to 0, which is the CSM required rate of 54.9254 ms\r
- //\r
- Private->Cpu->RegisterInterruptHandler (\r
- Private->Cpu,\r
- TimerVector,\r
- NULL\r
- );\r
- SetPitCount (0);\r
-\r
- //\r
- // Save status that the Timer AP is not using the 8254 PIT\r
- //\r
- Private->TimerUses8254 = FALSE;\r
- } else if (Status == EFI_ALREADY_STARTED) {\r
- //\r
- // Save status that the Timer AP is using the 8254 PIT\r
- //\r
- Private->TimerUses8254 = TRUE;\r
- } else {\r
- //\r
- // Unexpected status from CPU AP RegisterInterruptHandler()\r
- //\r
- ASSERT (FALSE);\r
- }\r
-\r
- return EFI_SUCCESS;\r
-}\r
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