diff options
Diffstat (limited to 'IntelFrameworkModulePkg/Csm/LegacyBiosDxe/Thunk.c')
| -rw-r--r-- | IntelFrameworkModulePkg/Csm/LegacyBiosDxe/Thunk.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/Thunk.c b/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/Thunk.c new file mode 100644 index 0000000000..c33288a2dd --- /dev/null +++ b/IntelFrameworkModulePkg/Csm/LegacyBiosDxe/Thunk.c @@ -0,0 +1,284 @@ +/** @file
+ Call into 16-bit BIOS code, Use AsmThunk16 function of BaseLib.
+
+Copyright (c) 2006 - 2010, 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 "LegacyBiosInterface.h"
+
+THUNK_CONTEXT mThunkContext;
+
+/**
+ 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
+ )
+{
+ 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;
+
+ return InternalLegacyBiosFarCall (
+ This,
+ (UINT16) (((UINT32 *)NULL)[BiosInt] >> 16),
+ (UINT16) ((UINT32 *)NULL)[BiosInt],
+ 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);
+}
+
+/**
+ 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;
+
+ 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 and disable interrutp of debug timer
+ //
+ InterruptState = SaveAndSetDebugTimerInterrupt (FALSE);
+
+ //
+ // The call to Legacy16 is a critical section to EFI
+ //
+ OriginalTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
+
+ 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);
+
+ //
+ // 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 (
+ {
+ UINTN EbdaBaseAddress;
+ UINTN ReservedEbdaBaseAddress;
+
+ EbdaBaseAddress = (*(UINT16 *) (UINTN) 0x40E) << 4;
+ ReservedEbdaBaseAddress = CONVENTIONAL_MEMORY_TOP - PcdGet32 (PcdEbdaReservedMemorySize);
+ ASSERT (ReservedEbdaBaseAddress <= EbdaBaseAddress);
+ }
+ );
+
+ 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;
+
+ //
+ // End critical section
+ //
+ gBS->RestoreTPL (OriginalTpl);
+
+ //
+ // Restore interrutp 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_PHYSICAL_ADDRESS MemoryAddress;
+
+ 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);
+
+ return EFI_SUCCESS;
+}
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