CloverBootloader/rEFIt_UEFI/Platform/LegacyBiosThunk.cpp
2022-04-26 00:55:56 +02:00

461 lines
14 KiB
C++

/** @file
Provide legacy thunk interface for accessing Bios Video Rom.
Copyright (c) 2006 - 2007, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include <Platform.h> // Only use angled for Platform, else, xcode project won't compile
#include <Efi.h>
#include "LegacyBiosThunk.h"
#include <posix/posix.h>
#ifndef DEBUG_ALL
#define DEBUG_LBTHUNK 0
#else
#define DEBUG_LBTHUNK DEBUG_ALL
#endif
#if DEBUG_LBTHUNK == 0
#define DBG(...)
#else
#define DBG(...) DebugLog(DEBUG_LBTHUNK, __VA_ARGS__)
#endif
#define EFI_CPU_EFLAGS_IF 0x200
extern EFI_LEGACY_8259_PROTOCOL *gLegacy8259;
extern THUNK_CONTEXT *mThunkContext;
/**
Initialize legacy environment for BIOS INI caller.
@param ThunkContext the instance pointer of THUNK_CONTEXT
**/
EFI_STATUS
InitializeBiosIntCaller (
// THUNK_CONTEXT *ThunkContext
)
{
EFI_STATUS Status;
UINT32 RealModeBufferSize;
UINT32 ExtraStackSize;
EFI_PHYSICAL_ADDRESS LegacyRegionBase;
UINT32 LegacyRegionSize;
//
// Get LegacyRegion
//
AsmGetThunk16Properties (&RealModeBufferSize, &ExtraStackSize);
LegacyRegionSize = (((RealModeBufferSize + ExtraStackSize) / EFI_PAGE_SIZE) + 1) * EFI_PAGE_SIZE;
LegacyRegionBase = 0x0C0000;
Status = gBS->AllocatePages (
AllocateMaxAddress,
EfiACPIMemoryNVS,
EFI_SIZE_TO_PAGES(LegacyRegionSize),
&LegacyRegionBase
);
// ASSERT_EFI_ERROR(Status);
if (EFI_ERROR(Status)) {
return Status;
}
mThunkContext->RealModeBuffer = (void*)(UINTN)LegacyRegionBase;
mThunkContext->RealModeBufferSize = LegacyRegionSize;
mThunkContext->ThunkAttributes = THUNK_ATTRIBUTE_DISABLE_A20_MASK_INT_15;
DBG("mThunkContext->RealModeBuffer: %llx, mThunkContext->RealModeBufferSize: %d\n", (uintptr_t)(mThunkContext->RealModeBuffer), mThunkContext->RealModeBufferSize);
AsmPrepareThunk16(mThunkContext);
return Status;
}
/**
Initialize interrupt redirection code and entries, because
IDT Vectors 0x68-0x6f must be redirected to IDT Vectors 0x08-0x0f.
Or the interrupt will lost when we do thunk.
NOTE: We do not reset 8259 vector base, because it will cause pending
interrupt lost.
@param Legacy8259 Instance pointer for EFI_LEGACY_8259_PROTOCOL.
**/
CONST UINT32 InterruptRedirectionCode[8] = {
0x90CF08CD, // INT8; IRET; NOP
0x90CF09CD, // INT9; IRET; NOP
0x90CF0ACD, // INTA; IRET; NOP
0x90CF0BCD, // INTB; IRET; NOP
0x90CF0CCD, // INTC; IRET; NOP
0x90CF0DCD, // INTD; IRET; NOP
0x90CF0ECD, // INTE; IRET; NOP
0x90CF0FCD // INTF; IRET; NOP
};
EFI_STATUS
InitializeInterruptRedirection (
// IN EFI_LEGACY_8259_PROTOCOL *Legacy8259
)
{
EFI_STATUS Status;
EFI_PHYSICAL_ADDRESS LegacyRegionBase;
UINTN LegacyRegionLength;
volatile UINT32 *IdtArray;
UINTN Index;
UINT8 ProtectedModeBaseVector;
//
// Get LegacyRegion
//
LegacyRegionLength = sizeof(InterruptRedirectionCode);
LegacyRegionBase = 0x0C0000;
Status = gBS->AllocatePages (
AllocateMaxAddress,
EfiACPIMemoryNVS,
EFI_SIZE_TO_PAGES(LegacyRegionLength),
&LegacyRegionBase
);
// ASSERT_EFI_ERROR(Status);
if (EFI_ERROR(Status)) {
return Status;
}
//
// Copy code to legacy region
//
CopyMem((void *)(UINTN)LegacyRegionBase, (void *)&InterruptRedirectionCode[0], sizeof (InterruptRedirectionCode));
//
// Get VectorBase, it should be 0x68
//
Status = gLegacy8259->GetVector (gLegacy8259, Efi8259Irq0, &ProtectedModeBaseVector);
// ASSERT_EFI_ERROR(Status);
if (EFI_ERROR(Status)) {
return Status;
}
//
// Patch IVT 0x68 ~ 0x6f
//
IdtArray = (UINT32 *) 0;
for (Index = 0; Index < 8; Index++) {
IdtArray[ProtectedModeBaseVector + Index] = ((EFI_SEGMENT (LegacyRegionBase + Index * 4)) << 16) | (EFI_OFFSET (LegacyRegionBase + Index * 4));
}
return Status;
}
/**
Disconnect EFI VGA driver
When BiosVideo disconnects, it takes care of setting Text VGA Mode (80x25) which works properly with Legacy mode
**/
EFI_STATUS
DisconnectVga ( void )
{
EFI_STATUS Status;
UINTN HandleCount = 0;
UINTN Index;
EFI_HANDLE *Handles = NULL;
EFI_PCI_IO_PROTOCOL *PciIo = NULL;
PCI_TYPE00 Pci;
// get all PciIo handles
Status = gBS->LocateHandleBuffer(ByProtocol, &gEfiPciIoProtocolGuid, NULL, &HandleCount, &Handles);
if (Status == EFI_SUCCESS) {
for (Index = 0; Index < HandleCount; Index++) {
Status = gBS->HandleProtocol(Handles[Index], &gEfiPciIoProtocolGuid, (void **) &PciIo);
if (EFI_ERROR(Status)) {
continue;
}
Status = PciIo->Pci.Read (PciIo, EfiPciIoWidthUint32, 0, sizeof (Pci) / sizeof (UINT32), &Pci);
if (!EFI_ERROR(Status))
{
if(IS_PCI_VGA(&Pci) == true)
{
// disconnect VGA
DBG("Disonnecting VGA\n");
Status = gBS->DisconnectController(Handles[Index], NULL, NULL);
DBG("disconnect %s", efiStrError(Status));
}
}
}
FreePool(Handles);
}
return Status;
}
/**
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 Reg Register contexted passed into (and returned) from thunk to 16-bit mode
@retval true Thunk completed, and there were no BIOS errors in the target code.
See Regs for status.
@retval false There was a BIOS erro in the target code.
**/
XBool
EFIAPI
LegacyBiosInt86 (
// IN BIOS_VIDEO_DEV *BiosDev,
IN UINT8 BiosInt,
IN IA32_REGISTER_SET *Regs
)
{
UINTN Status;
UINTN Eflags;
IA32_REGISTER_SET ThunkRegSet;
XBool Ret;
UINT16 *Stack16;
ZeroMem (&ThunkRegSet, sizeof (ThunkRegSet));
ThunkRegSet.E.EFLAGS.Bits.Reserved_0 = 1;
ThunkRegSet.E.EFLAGS.Bits.Reserved_1 = 0;
ThunkRegSet.E.EFLAGS.Bits.Reserved_2 = 0;
ThunkRegSet.E.EFLAGS.Bits.Reserved_3 = 0;
ThunkRegSet.E.EFLAGS.Bits.IOPL = 3;
ThunkRegSet.E.EFLAGS.Bits.NT = 0;
ThunkRegSet.E.EFLAGS.Bits.IF = 1;
ThunkRegSet.E.EFLAGS.Bits.TF = 0;
ThunkRegSet.E.EFLAGS.Bits.CF = 0;
ThunkRegSet.E.EDI = Regs->E.EDI;
ThunkRegSet.E.ESI = Regs->E.ESI;
ThunkRegSet.E.EBP = Regs->E.EBP;
ThunkRegSet.E.EBX = Regs->E.EBX;
ThunkRegSet.E.EDX = Regs->E.EDX;
ThunkRegSet.E.ECX = Regs->E.ECX;
ThunkRegSet.E.EAX = Regs->E.EAX;
ThunkRegSet.E.DS = Regs->E.DS;
ThunkRegSet.E.ES = Regs->E.ES;
//
// The call to Legacy16 is a critical section to EFI
//
Eflags = AsmReadEflags ();
if ((Eflags & EFI_CPU_EFLAGS_IF) != 0) {
DisableInterrupts ();
}
//
// Set Legacy16 state. 0x08, 0x70 is legacy 8259 vector bases.
//
Status = gLegacy8259->SetMode (gLegacy8259, Efi8259LegacyMode, NULL, NULL);
// ASSERT_EFI_ERROR(Status);
if (EFI_ERROR(Status)) {
return false;
}
Stack16 = (UINT16 *)((UINT8 *) mThunkContext->RealModeBuffer + mThunkContext->RealModeBufferSize - sizeof (UINT16));
ThunkRegSet.E.SS = (UINT16) (((UINTN) Stack16 >> 16) << 12);
ThunkRegSet.E.ESP = (UINT16) (UINTN) Stack16;
ThunkRegSet.E.Eip = *(UINT16*)(((UINTN)BiosInt) * sizeof(UINT32));
ThunkRegSet.E.CS = *(UINT16*)((((UINTN)BiosInt) * sizeof(UINT32)) + sizeof(UINT16));
mThunkContext->RealModeState = &ThunkRegSet;
AsmThunk16 (mThunkContext);
//
// Restore protected mode interrupt state
//
Status = gLegacy8259->SetMode (gLegacy8259, Efi8259ProtectedMode, NULL, NULL);
// ASSERT_EFI_ERROR(Status);
if (EFI_ERROR(Status)) {
return false;
}
//
// End critical section
//
if ((Eflags & EFI_CPU_EFLAGS_IF) != 0) {
EnableInterrupts ();
}
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->E.SS = ThunkRegSet.E.SS;
Regs->E.CS = ThunkRegSet.E.CS;
Regs->E.DS = ThunkRegSet.E.DS;
Regs->E.ES = ThunkRegSet.E.ES;
CopyMem(&(Regs->E.EFLAGS), &(ThunkRegSet.E.EFLAGS), sizeof (UINT32));
Ret = Regs->E.EFLAGS.Bits.CF == 1;
return Ret;
}
XBool
EFIAPI
LegacyBiosFarCall86 (
// IN EFI_LEGACY_BIOS_THUNK_PROTOCOL *This,
IN UINT16 Segment,
IN UINT16 Offset,
IN IA32_REGISTER_SET *Regs
// IN void *Stack
// IN UINTN StackSize
)
{
UINTN Status;
UINT32 Eflags;
IA32_REGISTER_SET ThunkRegSet;
XBool Ret;
UINT16 *Stack16;
// UINT16 BiosInt = 0x100;
EFI_TPL OriginalTpl;
EFI_TIMER_ARCH_PROTOCOL *Timer;
UINT64 TimerPeriod = 0;
#if ENABLE_PS2MOUSE_LEGACYBOOT == 1
UINT16 LegacyMaskOld, LegacyMaskNew;
#endif
// Disconnect EFI VGA driver (and switch to Text VGA Mode)
DisconnectVga();
ZeroMem (&ThunkRegSet, sizeof (ThunkRegSet));
ThunkRegSet.E.EFLAGS.Bits.Reserved_0 = 1;
ThunkRegSet.E.EFLAGS.Bits.Reserved_1 = 0;
ThunkRegSet.E.EFLAGS.Bits.Reserved_2 = 0;
ThunkRegSet.E.EFLAGS.Bits.Reserved_3 = 0;
ThunkRegSet.E.EFLAGS.Bits.IOPL = 3;
ThunkRegSet.E.EFLAGS.Bits.NT = 0;
ThunkRegSet.E.EFLAGS.Bits.IF = 0; //why???
ThunkRegSet.E.EFLAGS.Bits.TF = 0;
ThunkRegSet.E.EFLAGS.Bits.CF = 0;
ThunkRegSet.E.EDI = Regs->E.EDI;
ThunkRegSet.E.ESI = Regs->E.ESI;
ThunkRegSet.E.EBP = Regs->E.EBP;
ThunkRegSet.E.EBX = Regs->E.EBX;
ThunkRegSet.E.EDX = Regs->E.EDX;
ThunkRegSet.E.ECX = Regs->E.ECX;
ThunkRegSet.E.EAX = Regs->E.EAX;
ThunkRegSet.E.DS = Regs->E.DS;
ThunkRegSet.E.ES = Regs->E.ES;
/* CopyMem(&(ThunkRegSet.E.EFLAGS), &(Regs->E.EFlags), sizeof (UINT32));
if ((Stack != NULL) && (StackSize != 0)) {
AsmThunk16SetUserStack (&mThunkContext, Stack, StackSize);
} */
//
// The call to Legacy16 is a critical section to EFI
//
Eflags = (UINT32)AsmReadEflags ();
if ((Eflags & EFI_CPU_EFLAGS_IF) != 0) {
DisableInterrupts ();
}
// DisableInterrupts ();
// Critical section - execute without interruption until Legacy boots
OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
//xxx - Slice
//AsmWriteIdtr(NULL);
Stack16 = (UINT16 *)((UINT8 *) mThunkContext->RealModeBuffer + mThunkContext->RealModeBufferSize - sizeof (UINT16));
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;
DBG("SS=%hX, ESP=%X, CS=%hX, Eip=%X\n", ThunkRegSet.E.SS, ThunkRegSet.E.ESP, ThunkRegSet.E.CS, ThunkRegSet.E.Eip);
#if DEBUG_LBTHUNK == 2
PauseForKey("LegacyBiosFarCall86"_XS8);
#endif
// Save current rate of DXE Timer and disable DXE timer
Status = gBS->LocateProtocol(gEfiTimerArchProtocolGuid, NULL, (void **) &Timer);
if (!EFI_ERROR(Status)) {
Timer->GetTimerPeriod (Timer, &TimerPeriod);
Timer->SetTimerPeriod (Timer, 0);
}
// Before switching to Legacy vector base, we set timer to default Legacy rate (54.9254 ms) - this is done by 3 steps:
IoWrite8 (TIMER_CONTROL_PORT, TIMER0_CONTROL_WORD);
IoWrite8 (TIMER0_COUNT_PORT, 0x00);
IoWrite8 (TIMER0_COUNT_PORT, 0x00);
// Set Irq Vector base to default Legacy base (master at 0x08, slave at 0x70)
gLegacy8259->SetVectorBase (gLegacy8259, LEGACY_MODE_BASE_VECTOR_MASTER, LEGACY_MODE_BASE_VECTOR_SLAVE);
// Set Irq Mask according to Legacy mode
#if ENABLE_PS2MOUSE_LEGACYBOOT == 1
// Update the Mask to allow also PS2 Mouse usage (which requires also Secondary PIC cascade)
gLegacy8259->GetMask (gLegacy8259, &LegacyMaskOld, NULL, NULL, NULL);
LegacyMaskNew = LegacyMaskOld & 0xEFFB;
gLegacy8259->SetMode (gLegacy8259, Efi8259LegacyMode, &LegacyMaskNew, NULL);
#else
gLegacy8259->SetMode (gLegacy8259, Efi8259LegacyMode, NULL, NULL);
#endif
// Thunk to 16-bit real mode to execute the farcall
AsmThunk16 (mThunkContext);
// EFI is probably overwritten here, but just in case we continue, try to restore EFI to previous state:
#if ENABLE_PS2MOUSE_LEGACYBOOT == 1
// Restore original Legacy Mask, as it was changed by our call to SetMode with the new mask
gLegacy8259->SetMask (gLegacy8259, &LegacyMaskOld, NULL, NULL, NULL);
#endif
// Set Irq Mask according to Protected mode
gLegacy8259->SetMode (gLegacy8259, Efi8259ProtectedMode, NULL, NULL);
// Set Irq Vector base to Protected vector base (master at 0x68, slave at 0x70)
gLegacy8259->SetVectorBase (gLegacy8259, PROTECTED_MODE_BASE_VECTOR_MASTER, PROTECTED_MODE_BASE_VECTOR_SLAVE);
// Enable and restore rate of DXE Timer
Timer->SetTimerPeriod (Timer, TimerPeriod);
// End critical section
gBS->RestoreTPL (OriginalTpl);
//
// End critical section
//
if ((Eflags & EFI_CPU_EFLAGS_IF) != 0) {
EnableInterrupts ();
}
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->E.SS = ThunkRegSet.E.SS;
Regs->E.CS = ThunkRegSet.E.CS;
Regs->E.DS = ThunkRegSet.E.DS;
Regs->E.ES = ThunkRegSet.E.ES;
CopyMem(&(Regs->E.EFLAGS), &(ThunkRegSet.E.EFLAGS), sizeof (UINT32));
Ret = Regs->E.EFLAGS.Bits.CF == 1;
// Connect VGA EFI Driver
BdsLibConnectAllDriversToAllControllers();
return Ret;
}