Save processor state during kernel initialization

xtoskrnl/includes/amd64/ke.h

@@ -41,6 +41,10 @@ KepInitializeThreadContext(IN PKTHREAD Thread,
                            IN PVOID StartContext,
                            IN PCONTEXT ContextRecord);
 
+XTAPI
+VOID
+KepSaveProcessorState(OUT PKPROCESSOR_STATE CpuState);
+
 XTAPI
 VOID
 KepStartKernel(VOID);

xtoskrnl/includes/i686/ke.h

@@ -41,6 +41,10 @@ KepInitializeThreadContext(IN PKTHREAD Thread,
                            IN PVOID StartContext,
                            IN PCONTEXT ContextRecord);
 
+XTAPI
+VOID
+KepSaveProcessorState(OUT PKPROCESSOR_STATE CpuState);
+
 XTAPI
 VOID
 KepStartKernel(VOID);

xtoskrnl/ke/amd64/krnlinit.c

@@ -35,6 +35,9 @@ KepInitializeKernel(VOID)
     /* Initialize CPU power state structures */
     PoInitializeProcessorControlBlock(Prcb);
 
+    /* Save processor state */
+    KepSaveProcessorState(&Prcb->ProcessorState);
+
     /* Initialize Idle process */
     RtlInitializeListHead(&KepProcessListHead);
     PageDirectory[0] = 0;

xtoskrnl/ke/amd64/proc.c

@@ -51,3 +51,50 @@ KeGetCurrentThread(VOID)
 {
     return (PKTHREAD)ArReadGSQuadWord(FIELD_OFFSET(KPROCESSOR_BLOCK, Prcb.CurrentThread));
 }
+
+/**
+ * Saves the current processor state.
+ *
+ * @param State
+ *        Supplies a pointer to the processor state structure.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+KepSaveProcessorState(OUT PKPROCESSOR_STATE CpuState)
+{
+    /* Save CR registers */
+    CpuState->SpecialRegisters.Cr0 = ArReadControlRegister(0);
+    CpuState->SpecialRegisters.Cr2 = ArReadControlRegister(2);
+    CpuState->SpecialRegisters.Cr3 = ArReadControlRegister(3);
+    CpuState->SpecialRegisters.Cr4 = ArReadControlRegister(4);
+    CpuState->SpecialRegisters.Cr8 = ArReadControlRegister(8);
+
+    /* Save DR registers */
+    CpuState->SpecialRegisters.KernelDr0 = ArReadDebugRegister(0);
+    CpuState->SpecialRegisters.KernelDr1 = ArReadDebugRegister(1);
+    CpuState->SpecialRegisters.KernelDr2 = ArReadDebugRegister(2);
+    CpuState->SpecialRegisters.KernelDr3 = ArReadDebugRegister(3);
+    CpuState->SpecialRegisters.KernelDr6 = ArReadDebugRegister(6);
+    CpuState->SpecialRegisters.KernelDr7 = ArReadDebugRegister(7);
+
+    /* Save MSR registers */
+    CpuState->SpecialRegisters.MsrGsBase = ArReadModelSpecificRegister(X86_MSR_GSBASE);
+    CpuState->SpecialRegisters.MsrGsSwap = ArReadModelSpecificRegister(X86_MSR_KERNEL_GSBASE);
+    CpuState->SpecialRegisters.MsrCStar = ArReadModelSpecificRegister(X86_MSR_CSTAR);
+    CpuState->SpecialRegisters.MsrLStar = ArReadModelSpecificRegister(X86_MSR_LSTAR);
+    CpuState->SpecialRegisters.MsrStar = ArReadModelSpecificRegister(X86_MSR_STAR);
+    CpuState->SpecialRegisters.MsrSyscallMask = ArReadModelSpecificRegister(X86_MSR_FMASK);
+
+    /* Save XMM control/status register */
+    CpuState->SpecialRegisters.MxCsr = ArReadMxCsrRegister();
+
+    /* Save GDT, IDT, LDT and TaskRegister */
+    ArStoreGlobalDescriptorTable(&CpuState->SpecialRegisters.Gdtr.Limit);
+    ArStoreInterruptDescriptorTable(&CpuState->SpecialRegisters.Idtr.Limit);
+    ArStoreLocalDescriptorTable(&CpuState->SpecialRegisters.Ldtr);
+    ArStoreTaskRegister(&CpuState->SpecialRegisters.Tr);
+}

xtoskrnl/ke/i686/krnlinit.c

@@ -35,6 +35,9 @@ KepInitializeKernel(VOID)
     /* Initialize CPU power state structures */
     PoInitializeProcessorControlBlock(Prcb);
 
+    /* Save processor state */
+    KepSaveProcessorState(&Prcb->ProcessorState);
+
     /* Initialize Idle process */
     RtlInitializeListHead(&KepProcessListHead);
     PageDirectory[0] = 0;

xtoskrnl/ke/i686/proc.c

@@ -51,3 +51,41 @@ KeGetCurrentThread(VOID)
 {
     return (PKTHREAD)ArReadFSDualWord(FIELD_OFFSET(KPROCESSOR_BLOCK, Prcb.CurrentThread));
 }
+
+/**
+ * Saves the current processor state.
+ *
+ * @param State
+ *        Supplies a pointer to the processor state structure.
+ *
+ * @return This routine does not return any value.
+ *
+ * @since XT 1.0
+ */
+XTAPI
+VOID
+KepSaveProcessorState(OUT PKPROCESSOR_STATE CpuState)
+{
+    /* Save CR registers */
+    CpuState->SpecialRegisters.Cr0 = ArReadControlRegister(0);
+    CpuState->SpecialRegisters.Cr2 = ArReadControlRegister(2);
+    CpuState->SpecialRegisters.Cr3 = ArReadControlRegister(3);
+    CpuState->SpecialRegisters.Cr4 = ArReadControlRegister(4);
+
+    /* Save DR registers */
+    CpuState->SpecialRegisters.KernelDr0 = ArReadDebugRegister(0);
+    CpuState->SpecialRegisters.KernelDr1 = ArReadDebugRegister(1);
+    CpuState->SpecialRegisters.KernelDr2 = ArReadDebugRegister(2);
+    CpuState->SpecialRegisters.KernelDr3 = ArReadDebugRegister(3);
+    CpuState->SpecialRegisters.KernelDr6 = ArReadDebugRegister(6);
+    CpuState->SpecialRegisters.KernelDr7 = ArReadDebugRegister(7);
+
+    /* Save XMM control/status register */
+    CpuState->SpecialRegisters.MxCsr = ArReadMxCsrRegister();
+
+    /* Save GDT, IDT, LDT and TaskRegister */
+    ArStoreGlobalDescriptorTable(&CpuState->SpecialRegisters.Gdtr.Limit);
+    ArStoreInterruptDescriptorTable(&CpuState->SpecialRegisters.Idtr.Limit);
+    ArStoreLocalDescriptorTable(&CpuState->SpecialRegisters.Ldtr);
+    ArStoreTaskRegister(&CpuState->SpecialRegisters.Tr);
+}