diff options
Diffstat (limited to 'OvmfPkg/Csm/LegacyBiosDxe/Thunk.c')
| -rw-r--r-- | OvmfPkg/Csm/LegacyBiosDxe/Thunk.c | 422 |
1 files changed, 0 insertions, 422 deletions
diff --git a/OvmfPkg/Csm/LegacyBiosDxe/Thunk.c b/OvmfPkg/Csm/LegacyBiosDxe/Thunk.c deleted file mode 100644 index 62f19b6..0000000 --- a/OvmfPkg/Csm/LegacyBiosDxe/Thunk.c +++ /dev/null @@ -1,422 +0,0 @@ -/** @file
- Call into 16-bit BIOS code, Use AsmThunk16 function of BaseLib.
-
-Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>
-
-SPDX-License-Identifier: BSD-2-Clause-Patent
-
-**/
-
-#include "LegacyBiosInterface.h"
-
-THUNK_CONTEXT mThunkContext;
-
-/**
- Sets the counter value for Timer #0 in a legacy 8254 timer.
-
- @param Count - The 16-bit counter value to program into Timer #0 of the legacy 8254 timer.
-
-**/
-VOID
-SetPitCount (
- IN UINT16 Count
- )
-{
- IoWrite8 (TIMER_CONTROL_PORT, TIMER0_CONTROL_WORD);
- IoWrite8 (TIMER0_COUNT_PORT, (UINT8)(Count & 0xFF));
- IoWrite8 (TIMER0_COUNT_PORT, (UINT8)((Count>>8) & 0xFF));
-}
-
-/**
- Thunk to 16-bit real mode and execute a software interrupt with a vector
- of BiosInt. Regs will contain the 16-bit register context on entry and
- exit.
-
- @param This Protocol instance pointer.
- @param BiosInt Processor interrupt vector to invoke
- @param Regs Register contexted passed into (and returned) from thunk to
- 16-bit mode
-
- @retval FALSE Thunk completed, and there were no BIOS errors in the target code.
- See Regs for status.
- @retval TRUE There was a BIOS erro in the target code.
-
-**/
-BOOLEAN
-EFIAPI
-LegacyBiosInt86 (
- IN EFI_LEGACY_BIOS_PROTOCOL *This,
- IN UINT8 BiosInt,
- IN EFI_IA32_REGISTER_SET *Regs
- )
-{
- UINT16 Segment;
- UINT16 Offset;
-
- Regs->X.Flags.Reserved1 = 1;
- Regs->X.Flags.Reserved2 = 0;
- Regs->X.Flags.Reserved3 = 0;
- Regs->X.Flags.Reserved4 = 0;
- Regs->X.Flags.IOPL = 3;
- Regs->X.Flags.NT = 0;
- Regs->X.Flags.IF = 0;
- Regs->X.Flags.TF = 0;
- Regs->X.Flags.CF = 0;
- //
- // The base address of legacy interrupt vector table is 0.
- // We use this base address to get the legacy interrupt handler.
- //
- ACCESS_PAGE0_CODE (
- Segment = (UINT16)(((UINT32 *)0)[BiosInt] >> 16);
- Offset = (UINT16)((UINT32 *)0)[BiosInt];
- );
-
- return InternalLegacyBiosFarCall (
- This,
- Segment,
- Offset,
- Regs,
- &Regs->X.Flags,
- sizeof (Regs->X.Flags)
- );
-}
-
-/**
- Thunk to 16-bit real mode and call Segment:Offset. Regs will contain the
- 16-bit register context on entry and exit. Arguments can be passed on
- the Stack argument
-
- @param This Protocol instance pointer.
- @param Segment Segemnt of 16-bit mode call
- @param Offset Offset of 16-bit mdoe call
- @param Regs Register contexted passed into (and returned) from
- thunk to 16-bit mode
- @param Stack Caller allocated stack used to pass arguments
- @param StackSize Size of Stack in bytes
-
- @retval FALSE Thunk completed, and there were no BIOS errors in
- the target code. See Regs for status.
- @retval TRUE There was a BIOS erro in the target code.
-
-**/
-BOOLEAN
-EFIAPI
-LegacyBiosFarCall86 (
- IN EFI_LEGACY_BIOS_PROTOCOL *This,
- IN UINT16 Segment,
- IN UINT16 Offset,
- IN EFI_IA32_REGISTER_SET *Regs,
- IN VOID *Stack,
- IN UINTN StackSize
- )
-{
- Regs->X.Flags.Reserved1 = 1;
- Regs->X.Flags.Reserved2 = 0;
- Regs->X.Flags.Reserved3 = 0;
- Regs->X.Flags.Reserved4 = 0;
- Regs->X.Flags.IOPL = 3;
- Regs->X.Flags.NT = 0;
- Regs->X.Flags.IF = 1;
- Regs->X.Flags.TF = 0;
- Regs->X.Flags.CF = 0;
-
- return InternalLegacyBiosFarCall (This, Segment, Offset, Regs, Stack, StackSize);
-}
-
-/**
- Provide NULL interrupt handler which is used to check
- if there is more than one HW interrupt registers with the CPU AP.
-
- @param InterruptType - The type of interrupt that occurred
- @param SystemContext - A pointer to the system context when the interrupt occurred
-
-**/
-VOID
-EFIAPI
-LegacyBiosNullInterruptHandler (
- IN EFI_EXCEPTION_TYPE InterruptType,
- IN EFI_SYSTEM_CONTEXT SystemContext
- )
-{
-}
-
-/**
- Thunk to 16-bit real mode and call Segment:Offset. Regs will contain the
- 16-bit register context on entry and exit. Arguments can be passed on
- the Stack argument
-
- @param This Protocol instance pointer.
- @param Segment Segemnt of 16-bit mode call
- @param Offset Offset of 16-bit mdoe call
- @param Regs Register contexted passed into (and returned) from thunk to
- 16-bit mode
- @param Stack Caller allocated stack used to pass arguments
- @param StackSize Size of Stack in bytes
-
- @retval FALSE Thunk completed, and there were no BIOS errors in the target code.
- See Regs for status.
- @retval TRUE There was a BIOS erro in the target code.
-
-**/
-BOOLEAN
-EFIAPI
-InternalLegacyBiosFarCall (
- IN EFI_LEGACY_BIOS_PROTOCOL *This,
- IN UINT16 Segment,
- IN UINT16 Offset,
- IN EFI_IA32_REGISTER_SET *Regs,
- IN VOID *Stack,
- IN UINTN StackSize
- )
-{
- UINTN Status;
- LEGACY_BIOS_INSTANCE *Private;
- UINT16 *Stack16;
- EFI_TPL OriginalTpl;
- IA32_REGISTER_SET ThunkRegSet;
- BOOLEAN InterruptState;
- UINT64 TimerPeriod;
-
- Private = LEGACY_BIOS_INSTANCE_FROM_THIS (This);
-
- ZeroMem (&ThunkRegSet, sizeof (ThunkRegSet));
- ThunkRegSet.X.DI = Regs->X.DI;
- ThunkRegSet.X.SI = Regs->X.SI;
- ThunkRegSet.X.BP = Regs->X.BP;
- ThunkRegSet.X.BX = Regs->X.BX;
- ThunkRegSet.X.DX = Regs->X.DX;
- //
- // Sometimes, ECX is used to pass in 32 bit data. For example, INT 1Ah, AX = B10Dh is
- // "PCI BIOS v2.0c + Write Configuration DWORD" and ECX has the dword to write.
- //
- ThunkRegSet.E.ECX = Regs->E.ECX;
- ThunkRegSet.X.AX = Regs->X.AX;
- ThunkRegSet.E.DS = Regs->X.DS;
- ThunkRegSet.E.ES = Regs->X.ES;
-
- CopyMem (&(ThunkRegSet.E.EFLAGS.UintN), &(Regs->X.Flags), sizeof (Regs->X.Flags));
-
- //
- // Clear the error flag; thunk code may set it. Stack16 should be the high address
- // Make Statk16 address the low 16 bit must be not zero.
- //
- Stack16 = (UINT16 *)((UINT8 *)mThunkContext.RealModeBuffer + mThunkContext.RealModeBufferSize - sizeof (UINT16));
-
- //
- // Save current rate of DXE Timer
- //
- Private->Timer->GetTimerPeriod (Private->Timer, &TimerPeriod);
-
- //
- // Disable DXE Timer while executing in real mode
- //
- Private->Timer->SetTimerPeriod (Private->Timer, 0);
-
- //
- // Save and disable interrupt of debug timer
- //
- InterruptState = SaveAndSetDebugTimerInterrupt (FALSE);
-
- //
- // The call to Legacy16 is a critical section to EFI
- //
- OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
-
- //
- // Check to see if there is more than one HW interrupt registers with the CPU AP.
- // If there is, then ASSERT() since that is not compatible with the CSM because
- // interupts other than the Timer interrupt that was disabled above can not be
- // handled properly from real mode.
- //
- DEBUG_CODE_BEGIN ();
- UINTN Vector;
- UINTN Count;
-
- for (Vector = 0x20, Count = 0; Vector < 0x100; Vector++) {
- Status = Private->Cpu->RegisterInterruptHandler (Private->Cpu, Vector, LegacyBiosNullInterruptHandler);
- if (Status == EFI_ALREADY_STARTED) {
- Count++;
- }
-
- if (Status == EFI_SUCCESS) {
- Private->Cpu->RegisterInterruptHandler (Private->Cpu, Vector, NULL);
- }
- }
-
- if (Count >= 2) {
- DEBUG ((DEBUG_ERROR, "ERROR: More than one HW interrupt active with CSM enabled\n"));
- }
-
- ASSERT (Count < 2);
- DEBUG_CODE_END ();
-
- //
- // If the Timer AP has enabled the 8254 timer IRQ and the current 8254 timer
- // period is less than the CSM required rate of 54.9254, then force the 8254
- // PIT counter to 0, which is the CSM required rate of 54.9254 ms
- //
- if (Private->TimerUses8254 && (TimerPeriod < 549254)) {
- SetPitCount (0);
- }
-
- if ((Stack != NULL) && (StackSize != 0)) {
- //
- // Copy Stack to low memory stack
- //
- Stack16 -= StackSize / sizeof (UINT16);
- CopyMem (Stack16, Stack, StackSize);
- }
-
- ThunkRegSet.E.SS = (UINT16)(((UINTN)Stack16 >> 16) << 12);
- ThunkRegSet.E.ESP = (UINT16)(UINTN)Stack16;
- ThunkRegSet.E.CS = Segment;
- ThunkRegSet.E.Eip = Offset;
-
- mThunkContext.RealModeState = &ThunkRegSet;
-
- //
- // Set Legacy16 state. 0x08, 0x70 is legacy 8259 vector bases.
- //
- Status = Private->Legacy8259->SetMode (Private->Legacy8259, Efi8259LegacyMode, NULL, NULL);
- ASSERT_EFI_ERROR (Status);
-
- AsmThunk16 (&mThunkContext);
-
- if ((Stack != NULL) && (StackSize != 0)) {
- //
- // Copy low memory stack to Stack
- //
- CopyMem (Stack, Stack16, StackSize);
- }
-
- //
- // Restore protected mode interrupt state
- //
- Status = Private->Legacy8259->SetMode (Private->Legacy8259, Efi8259ProtectedMode, NULL, NULL);
- ASSERT_EFI_ERROR (Status);
-
- mThunkContext.RealModeState = NULL;
-
- //
- // Enable and restore rate of DXE Timer
- //
- Private->Timer->SetTimerPeriod (Private->Timer, TimerPeriod);
-
- //
- // End critical section
- //
- gBS->RestoreTPL (OriginalTpl);
-
- //
- // OPROM may allocate EBDA range by itself and change EBDA base and EBDA size.
- // Get the current EBDA base address, and compared with pre-allocate minimum
- // EBDA base address, if the current EBDA base address is smaller, it indicates
- // PcdEbdaReservedMemorySize should be adjusted to larger for more OPROMs.
- //
- DEBUG_CODE_BEGIN ();
- {
- UINTN EbdaBaseAddress;
- UINTN ReservedEbdaBaseAddress;
-
- ACCESS_PAGE0_CODE (
- EbdaBaseAddress = (*(UINT16 *)(UINTN)0x40E) << 4;
- ReservedEbdaBaseAddress = CONVENTIONAL_MEMORY_TOP
- - PcdGet32 (PcdEbdaReservedMemorySize);
- ASSERT (ReservedEbdaBaseAddress <= EbdaBaseAddress);
- );
- }
- DEBUG_CODE_END ();
-
- //
- // Restore interrupt of debug timer
- //
- SaveAndSetDebugTimerInterrupt (InterruptState);
-
- Regs->E.EDI = ThunkRegSet.E.EDI;
- Regs->E.ESI = ThunkRegSet.E.ESI;
- Regs->E.EBP = ThunkRegSet.E.EBP;
- Regs->E.EBX = ThunkRegSet.E.EBX;
- Regs->E.EDX = ThunkRegSet.E.EDX;
- Regs->E.ECX = ThunkRegSet.E.ECX;
- Regs->E.EAX = ThunkRegSet.E.EAX;
- Regs->X.SS = ThunkRegSet.E.SS;
- Regs->X.CS = ThunkRegSet.E.CS;
- Regs->X.DS = ThunkRegSet.E.DS;
- Regs->X.ES = ThunkRegSet.E.ES;
-
- CopyMem (&(Regs->X.Flags), &(ThunkRegSet.E.EFLAGS.UintN), sizeof (Regs->X.Flags));
-
- return (BOOLEAN)(Regs->X.Flags.CF == 1);
-}
-
-/**
- Allocate memory < 1 MB and copy the thunker code into low memory. Se up
- all the descriptors.
-
- @param Private Private context for Legacy BIOS
-
- @retval EFI_SUCCESS Should only pass.
-
-**/
-EFI_STATUS
-LegacyBiosInitializeThunk (
- IN LEGACY_BIOS_INSTANCE *Private
- )
-{
- EFI_STATUS Status;
- EFI_PHYSICAL_ADDRESS MemoryAddress;
- UINT8 TimerVector;
-
- MemoryAddress = (EFI_PHYSICAL_ADDRESS)(UINTN)Private->IntThunk;
-
- mThunkContext.RealModeBuffer = (VOID *)(UINTN)(MemoryAddress + ((sizeof (LOW_MEMORY_THUNK) / EFI_PAGE_SIZE) + 1) * EFI_PAGE_SIZE);
- mThunkContext.RealModeBufferSize = EFI_PAGE_SIZE;
- mThunkContext.ThunkAttributes = THUNK_ATTRIBUTE_BIG_REAL_MODE | THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15;
-
- AsmPrepareThunk16 (&mThunkContext);
-
- //
- // Get the interrupt vector number corresponding to IRQ0 from the 8259 driver
- //
- TimerVector = 0;
- Status = Private->Legacy8259->GetVector (Private->Legacy8259, Efi8259Irq0, &TimerVector);
- ASSERT_EFI_ERROR (Status);
-
- //
- // Check to see if the Timer AP has hooked the IRQ0 from the 8254 PIT
- //
- Status = Private->Cpu->RegisterInterruptHandler (
- Private->Cpu,
- TimerVector,
- LegacyBiosNullInterruptHandler
- );
- if (Status == EFI_SUCCESS) {
- //
- // If the Timer AP has not enabled the 8254 timer IRQ, then force the 8254 PIT
- // counter to 0, which is the CSM required rate of 54.9254 ms
- //
- Private->Cpu->RegisterInterruptHandler (
- Private->Cpu,
- TimerVector,
- NULL
- );
- SetPitCount (0);
-
- //
- // Save status that the Timer AP is not using the 8254 PIT
- //
- Private->TimerUses8254 = FALSE;
- } else if (Status == EFI_ALREADY_STARTED) {
- //
- // Save status that the Timer AP is using the 8254 PIT
- //
- Private->TimerUses8254 = TRUE;
- } else {
- //
- // Unexpected status from CPU AP RegisterInterruptHandler()
- //
- ASSERT (FALSE);
- }
-
- return EFI_SUCCESS;
-}
|