VOID
FASTCALL
KiEnterV86Mode(IN ULONG_PTR StackFrameUnaligned)
{
PKTHREAD Thread;
PKV8086_STACK_FRAME StackFrame = (PKV8086_STACK_FRAME)(ROUND_UP(StackFrameUnaligned - 4, 16) + 4);
PKTRAP_FRAME TrapFrame = &StackFrame->TrapFrame;
PKV86_FRAME V86Frame = &StackFrame->V86Frame;
PFX_SAVE_AREA NpxFrame = &StackFrame->NpxArea;
ASSERT((ULONG_PTR)NpxFrame % 16 == 0);
/* Build fake user-mode trap frame */
TrapFrame->SegCs = KGDT_R0_CODE | RPL_MASK;
TrapFrame->SegEs = TrapFrame->SegDs = TrapFrame->SegFs = TrapFrame->SegGs = 0;
TrapFrame->ErrCode = 0;
/* Get the current thread's initial stack */
Thread = KeGetCurrentThread();
V86Frame->ThreadStack = KiGetThreadNpxArea(Thread);
/* Save TEB addresses */
V86Frame->ThreadTeb = Thread->Teb;
V86Frame->PcrTeb = KeGetPcr()->NtTib.Self;
/* Save return EIP */
TrapFrame->Eip = (ULONG_PTR)Ki386BiosCallReturnAddress;
/* Save our stack (after the frames) */
TrapFrame->Esi = StackFrameUnaligned;
TrapFrame->Edi = (ULONG_PTR)_AddressOfReturnAddress() + 4;
/* Sanitize EFlags and enable interrupts */
TrapFrame->EFlags = __readeflags() & 0x60DD7;
TrapFrame->EFlags |= EFLAGS_INTERRUPT_MASK;
/* Fill out the rest of the frame */
TrapFrame->HardwareSegSs = KGDT_R3_DATA | RPL_MASK;
TrapFrame->HardwareEsp = 0x11FFE;
TrapFrame->ExceptionList = EXCEPTION_CHAIN_END;
TrapFrame->Dr7 = 0;
/* Set some debug fields if trap debugging is enabled */
KiFillTrapFrameDebug(TrapFrame);
/* Disable interrupts */
_disable();
/* Copy the thread's NPX frame */
RtlCopyMemory(NpxFrame, V86Frame->ThreadStack, sizeof(FX_SAVE_AREA));
/* Clear exception list */
KeGetPcr()->NtTib.ExceptionList = EXCEPTION_CHAIN_END;
/* Set new ESP0 */
KeGetPcr()->TSS->Esp0 = (ULONG_PTR)&TrapFrame->V86Es;
/* Set new initial stack */
Thread->InitialStack = V86Frame;
/* Set VDM TEB */
Thread->Teb = (PTEB)TRAMPOLINE_TEB;
KiSetTebBase(KeGetPcr(), (PVOID)TRAMPOLINE_TEB);
/* Enable interrupts */
_enable();
/* Start VDM execution */
NtVdmControl(VdmStartExecution, NULL);
/* Exit to V86 mode */
KiEoiHelper(TrapFrame);
}
ULONG_PTR
FASTCALL
KiExitV86Mode(IN PKTRAP_FRAME TrapFrame)
{
PKV8086_STACK_FRAME StackFrame;
PKTHREAD Thread;
PKTRAP_FRAME PmTrapFrame;
PKV86_FRAME V86Frame;
PFX_SAVE_AREA NpxFrame;
/* Get the stack frame back */
StackFrame = CONTAINING_RECORD(TrapFrame->Esi, KV8086_STACK_FRAME, V86Frame);
PmTrapFrame = &StackFrame->TrapFrame;
V86Frame = &StackFrame->V86Frame;
NpxFrame = &StackFrame->NpxArea;
/* Copy the FPU frame back */
Thread = KeGetCurrentThread();
RtlCopyMemory(KiGetThreadNpxArea(Thread), NpxFrame, sizeof(FX_SAVE_AREA));
/* Set initial stack back */
Thread->InitialStack = (PVOID)((ULONG_PTR)V86Frame->ThreadStack + sizeof(FX_SAVE_AREA));
/* Set ESP0 back in the KTSS */
KeGetPcr()->TSS->Esp0 = (ULONG_PTR)&PmTrapFrame->V86Es;
/* Restore TEB addresses */
Thread->Teb = V86Frame->ThreadTeb;
KiSetTebBase(KeGetPcr(), V86Frame->ThreadTeb);
/* Enable interrupts and return a pointer to the trap frame */
_enable();
return (ULONG)PmTrapFrame;
}
DECLSPEC_NORETURN
VOID
FASTCALL
KiTrap07Handler(IN PKTRAP_FRAME TrapFrame)
{
PKTHREAD Thread, NpxThread;
PFX_SAVE_AREA SaveArea, NpxSaveArea;
ULONG Cr0;
/* Save trap frame */
KiEnterTrap(TrapFrame);
/* Try to handle NPX delay load */
while (TRUE)
{
/* Get the current thread */
Thread = KeGetCurrentThread();
/* Get the NPX frame */
SaveArea = KiGetThreadNpxArea(Thread);
/* Check if emulation is enabled */
if (SaveArea->Cr0NpxState & CR0_EM)
{
/* Not implemented */
UNIMPLEMENTED;
while (TRUE);
}
/* Save CR0 and check NPX state */
Cr0 = __readcr0();
if (Thread->NpxState != NPX_STATE_LOADED)
{
/* Update CR0 */
Cr0 &= ~(CR0_MP | CR0_EM | CR0_TS);
__writecr0(Cr0);
/* Get the NPX thread */
NpxThread = KeGetCurrentPrcb()->NpxThread;
if (NpxThread)
{
/* Get the NPX frame */
NpxSaveArea = KiGetThreadNpxArea(NpxThread);
/* Save FPU state */
DPRINT("FIXME: Save FPU state: %p\n", NpxSaveArea);
//Ke386SaveFpuState(NpxSaveArea);
/* Update NPX state */
Thread->NpxState = NPX_STATE_NOT_LOADED;
}
/* Load FPU state */
//Ke386LoadFpuState(SaveArea);
/* Update NPX state */
Thread->NpxState = NPX_STATE_LOADED;
KeGetCurrentPrcb()->NpxThread = Thread;
/* Enable interrupts */
_enable();
/* Check if CR0 needs to be reloaded due to context switch */
if (!SaveArea->Cr0NpxState) KiEoiHelper(TrapFrame);
/* Otherwise, we need to reload CR0, disable interrupts */
_disable();
/* Reload CR0 */
Cr0 = __readcr0();
Cr0 |= SaveArea->Cr0NpxState;
__writecr0(Cr0);
/* Now restore interrupts and check for TS */
_enable();
if (Cr0 & CR0_TS) KiEoiHelper(TrapFrame);
/* We're still here -- clear TS and try again */
__writecr0(__readcr0() &~ CR0_TS);
_disable();
}
else
{
/* This is an actual fault, not a lack of FPU state */
break;
}
}
/* TS should not be set */
if (Cr0 & CR0_TS)
{
/*
* If it's incorrectly set, then maybe the state is actually still valid
* but we could've lock track of that due to a BIOS call.
* Make sure MP is still set, which should verify the theory.
*/
if (Cr0 & CR0_MP)
{
/* Indeed, the state is actually still valid, so clear TS */
__writecr0(__readcr0() &~ CR0_TS);
KiEoiHelper(TrapFrame);
}
/* Otherwise, something strange is going on */
KeBugCheckWithTf(TRAP_CAUSE_UNKNOWN, 2, Cr0, 0, 0, TrapFrame);
}
/* It's not a delayed load, so process this trap as an NPX fault */
KiNpxHandler(TrapFrame, Thread, SaveArea);
}
VOID
NTAPI
INIT_FUNCTION
KiInitMachineDependent(VOID)
{
ULONG CpuCount;
BOOLEAN FbCaching = FALSE;
NTSTATUS Status;
ULONG ReturnLength;
ULONG i, Affinity, Sample = 0;
PFX_SAVE_AREA FxSaveArea;
ULONG MXCsrMask = 0xFFBF;
ULONG Dummy;
KI_SAMPLE_MAP Samples[4];
PKI_SAMPLE_MAP CurrentSample = Samples;
/* Check for large page support */
if (KeFeatureBits & KF_LARGE_PAGE)
{
/* FIXME: Support this */
DPRINT("Large Page support detected but not yet taken advantage of\n");
}
/* Check for global page support */
if (KeFeatureBits & KF_GLOBAL_PAGE)
{
/* Do an IPI to enable it on all CPUs */
CpuCount = KeNumberProcessors;
KeIpiGenericCall(Ki386EnableGlobalPage, (ULONG_PTR)&CpuCount);
}
/* Check for PAT and/or MTRR support */
if (KeFeatureBits & (KF_PAT | KF_MTRR))
{
/* Query the HAL to make sure we can use it */
Status = HalQuerySystemInformation(HalFrameBufferCachingInformation,
sizeof(BOOLEAN),
&FbCaching,
&ReturnLength);
if ((NT_SUCCESS(Status)) && (FbCaching))
{
/* We can't, disable it */
KeFeatureBits &= ~(KF_PAT | KF_MTRR);
}
}
/* Check for PAT support and enable it */
if (KeFeatureBits & KF_PAT) KiInitializePAT();
/* Assume no errata for now */
SharedUserData->ProcessorFeatures[PF_FLOATING_POINT_PRECISION_ERRATA] = 0;
/* Check if we have an NPX */
if (KeI386NpxPresent)
{
/* Loop every CPU */
i = KeActiveProcessors;
for (Affinity = 1; i; Affinity <<= 1)
{
/* Check if this is part of the set */
if (i & Affinity)
{
/* Run on this CPU */
i &= ~Affinity;
KeSetSystemAffinityThread(Affinity);
/* Detect FPU errata */
if (KiIsNpxErrataPresent())
{
/* Disable NPX support */
KeI386NpxPresent = FALSE;
SharedUserData->
ProcessorFeatures[PF_FLOATING_POINT_PRECISION_ERRATA] =
TRUE;
break;
}
}
}
}
/* If there's no NPX, then we're emulating the FPU */
SharedUserData->ProcessorFeatures[PF_FLOATING_POINT_EMULATED] =
!KeI386NpxPresent;
/* Check if there's no NPX, so that we can disable associated features */
if (!KeI386NpxPresent)
{
/* Remove NPX-related bits */
KeFeatureBits &= ~(KF_XMMI64 | KF_XMMI | KF_FXSR | KF_MMX);
/* Disable kernel flags */
KeI386FxsrPresent = KeI386XMMIPresent = FALSE;
/* Disable processor features that might've been set until now */
SharedUserData->ProcessorFeatures[PF_FLOATING_POINT_PRECISION_ERRATA] =
SharedUserData->ProcessorFeatures[PF_XMMI64_INSTRUCTIONS_AVAILABLE] =
SharedUserData->ProcessorFeatures[PF_XMMI_INSTRUCTIONS_AVAILABLE] =
SharedUserData->ProcessorFeatures[PF_3DNOW_INSTRUCTIONS_AVAILABLE] =
SharedUserData->ProcessorFeatures[PF_MMX_INSTRUCTIONS_AVAILABLE] = 0;
}
/* Check for CR4 support */
if (KeFeatureBits & KF_CR4)
{
/* Do an IPI call to enable the Debug Exceptions */
CpuCount = KeNumberProcessors;
KeIpiGenericCall(Ki386EnableDE, (ULONG_PTR)&CpuCount);
}
/* Check if FXSR was found */
if (KeFeatureBits & KF_FXSR)
{
/* Do an IPI call to enable the FXSR */
CpuCount = KeNumberProcessors;
KeIpiGenericCall(Ki386EnableFxsr, (ULONG_PTR)&CpuCount);
/* Check if XMM was found too */
if (KeFeatureBits & KF_XMMI)
{
/* Do an IPI call to enable XMMI exceptions */
CpuCount = KeNumberProcessors;
KeIpiGenericCall(Ki386EnableXMMIExceptions, (ULONG_PTR)&CpuCount);
/* FIXME: Implement and enable XMM Page Zeroing for Mm */
/* Patch the RtlPrefetchMemoryNonTemporal routine to enable it */
*(PCHAR)RtlPrefetchMemoryNonTemporal = 0x90;
}
}
/* Check for, and enable SYSENTER support */
KiRestoreFastSyscallReturnState();
/* Loop every CPU */
i = KeActiveProcessors;
for (Affinity = 1; i; Affinity <<= 1)
{
/* Check if this is part of the set */
if (i & Affinity)
{
/* Run on this CPU */
i &= ~Affinity;
KeSetSystemAffinityThread(Affinity);
/* Reset MHz to 0 for this CPU */
KeGetCurrentPrcb()->MHz = 0;
/* Check if we can use RDTSC */
if (KeFeatureBits & KF_RDTSC)
{
/* Start sampling loop */
for (;;)
{
/* Do a dummy CPUID to start the sample */
CPUID(0, &Dummy, &Dummy, &Dummy, &Dummy);
/* Fill out the starting data */
CurrentSample->PerfStart = KeQueryPerformanceCounter(NULL);
CurrentSample->TSCStart = __rdtsc();
CurrentSample->PerfFreq.QuadPart = -50000;
/* Sleep for this sample */
KeDelayExecutionThread(KernelMode,
FALSE,
&CurrentSample->PerfFreq);
/* Do another dummy CPUID */
CPUID(0, &Dummy, &Dummy, &Dummy, &Dummy);
/* Fill out the ending data */
CurrentSample->PerfEnd =
KeQueryPerformanceCounter(&CurrentSample->PerfFreq);
CurrentSample->TSCEnd = __rdtsc();
/* Calculate the differences */
CurrentSample->PerfDelta = CurrentSample->PerfEnd.QuadPart -
CurrentSample->PerfStart.QuadPart;
CurrentSample->TSCDelta = CurrentSample->TSCEnd -
CurrentSample->TSCStart;
/* Compute CPU Speed */
CurrentSample->MHz = (ULONG)((CurrentSample->TSCDelta *
CurrentSample->
PerfFreq.QuadPart + 500000) /
(CurrentSample->PerfDelta *
1000000));
/* Check if this isn't the first sample */
if (Sample)
{
/* Check if we got a good precision within 1MHz */
if ((CurrentSample->MHz == CurrentSample[-1].MHz) ||
(CurrentSample->MHz == CurrentSample[-1].MHz + 1) ||
(CurrentSample->MHz == CurrentSample[-1].MHz - 1))
{
/* We did, stop sampling */
break;
}
}
/* Move on */
CurrentSample++;
Sample++;
if (Sample == sizeof(Samples) / sizeof(Samples[0]))
{
/* Restart */
CurrentSample = Samples;
Sample = 0;
}
}
/* Save the CPU Speed */
KeGetCurrentPrcb()->MHz = CurrentSample[-1].MHz;
}
/* Check if we have MTRR */
if (KeFeatureBits & KF_MTRR)
{
/* Then manually initialize MTRR for the CPU */
KiInitializeMTRR(i ? FALSE : TRUE);
}
/* Check if we have AMD MTRR and initialize it for the CPU */
if (KeFeatureBits & KF_AMDK6MTRR) KiAmdK6InitializeMTRR();
/* Check if this is a buggy Pentium and apply the fixup if so */
if (KiI386PentiumLockErrataPresent) KiI386PentiumLockErrataFixup();
/* Check if the CPU supports FXSR */
if (KeFeatureBits & KF_FXSR)
{
/* Get the current thread NPX state */
FxSaveArea = KiGetThreadNpxArea(KeGetCurrentThread());
/* Clear initial MXCsr mask */
FxSaveArea->U.FxArea.MXCsrMask = 0;
/* Save the current NPX State */
Ke386SaveFpuState(FxSaveArea);
/* Check if the current mask doesn't match the reserved bits */
if (FxSaveArea->U.FxArea.MXCsrMask != 0)
{
/* Then use whatever it's holding */
MXCsrMask = FxSaveArea->U.FxArea.MXCsrMask;
}
/* Check if nobody set the kernel-wide mask */
if (!KiMXCsrMask)
{
/* Then use the one we calculated above */
KiMXCsrMask = MXCsrMask;
}
else
{
/* Was it set to the same value we found now? */
if (KiMXCsrMask != MXCsrMask)
{
/* No, something is definitely wrong */
KeBugCheckEx(MULTIPROCESSOR_CONFIGURATION_NOT_SUPPORTED,
KF_FXSR,
KiMXCsrMask,
MXCsrMask,
0);
}
}
/* Now set the kernel mask */
KiMXCsrMask &= MXCsrMask;
}
}
}
/* Return affinity back to where it was */
KeRevertToUserAffinityThread();
/* NT allows limiting the duration of an ISR with a registry key */
if (KiTimeLimitIsrMicroseconds)
{
/* FIXME: TODO */
DPRINT1("ISR Time Limit not yet supported\n");
}
/* Set CR0 features based on detected CPU */
KiSetCR0Bits();
}
