--- /dev/null
+/*
+ * COPYRIGHT: See COPYING.ARM in the top level directory
+ * PROJECT: ReactOS UEFI Boot Library
+ * FILE: boot/environ/lib/arch/i386/arch.c
+ * PURPOSE: Boot Library Architectural Initialization for i386
+ * PROGRAMMER: Alex Ionescu (alex.ionescu@reactos.org)
+ */
+
+/* INCLUDES ******************************************************************/
+
+#include "bl.h"
+
+/* DATA VARIABLES ************************************************************/
+
+BL_ARCH_CONTEXT FirmwareExecutionContext;
+BL_ARCH_CONTEXT ApplicationExecutionContext;
+PBL_ARCH_CONTEXT CurrentExecutionContext;
+
+/* FUNCTIONS *****************************************************************/
+
+VOID
+//__declspec(naked) fixme: gcc
+ArchTrapNoProcess (
+ VOID
+ )
+{
+ /* Do nothing, this is an unsupported debugging interrupt */
+ // _asm { iret } FIXME: GCC
+}
+
+VOID
+ArchSwitchContext (
+ _In_ PBL_ARCH_CONTEXT NewContext,
+ _In_ PBL_ARCH_CONTEXT OldContext
+ )
+{
+ /* Are we switching to real mode? */
+ if (NewContext->Mode == BlRealMode)
+ {
+ /* Disable paging */
+ __writecr0(__readcr0() & ~CR0_PG);
+
+ /* Are we coming from PAE mode? */
+ if ((OldContext != NULL) && (OldContext->TranslationType == BlPae))
+ {
+ /* Turn off PAE */
+ __writecr4(__readcr4() & ~CR4_PAE);
+ }
+
+ /* Enable interrupts */
+ _enable();
+ }
+ else
+ {
+ /* Switching to protected mode -- disable interrupts if needed */
+ if (!(NewContext->ContextFlags & BL_CONTEXT_INTERRUPTS_ON))
+ {
+ _disable();
+ }
+
+ /* Are we enabling paging for the first time? */
+ if (NewContext->ContextFlags & BL_CONTEXT_PAGING_ON)
+ {
+ /* In PAE mode? */
+ if (NewContext->TranslationType == BlPae)
+ {
+ /* Turn on PAE */
+ __writecr4(__readcr4() | CR4_PAE);
+ }
+
+ /* Turn on paging */
+ __writecr0(__readcr0() | CR0_PG);
+ }
+ }
+}
+
+NTSTATUS
+ArchInitializeContext (
+ _In_ PBL_ARCH_CONTEXT Context
+ )
+{
+ NTSTATUS Status = STATUS_SUCCESS;
+
+ /* Are we initializing real mode? */
+ if (Context->Mode == BlRealMode)
+ {
+ /* Disable paging, enable interrupts */
+ Context->ContextFlags &= ~BL_CONTEXT_PAGING_ON;
+ Context->ContextFlags |= BL_CONTEXT_INTERRUPTS_ON;
+ }
+ else if (!(BlpApplicationFlags & BL_APPLICATION_FLAG_CONVERTED_FROM_EFI) ||
+ (BlpLibraryParameters.TranslationType != BlNone))
+ {
+ /* Read the current translation type */
+ Context->TranslationType = BlpLibraryParameters.TranslationType;
+
+ /* Disable paging (it's already on), enable interrupts */
+ Context->ContextFlags &= ~BL_CONTEXT_PAGING_ON;
+ Context->ContextFlags |= BL_CONTEXT_INTERRUPTS_ON;
+
+ /* Enable FXSR support in the FPU */
+ __writecr4(__readcr4() | CR4_FXSR);
+ }
+ else
+ {
+ /* Invalid context */
+ Status = STATUS_NOT_SUPPORTED;
+ }
+
+ /* Return context status */
+ return Status;
+}
+
+NTSTATUS
+ArchInitializeContexts (
+ VOID
+ )
+{
+ PBL_ARCH_CONTEXT Context = NULL;
+ NTSTATUS EfiStatus, AppStatus;
+
+ /* No current context */
+ CurrentExecutionContext = NULL;
+
+ /* Setup the EFI and Application modes respectively */
+ FirmwareExecutionContext.Mode = BlRealMode;
+ ApplicationExecutionContext.Mode = BlProtectedMode;
+
+ /* Initialize application mode */
+ AppStatus = ArchInitializeContext(&ApplicationExecutionContext);
+ if (NT_SUCCESS(AppStatus))
+ {
+ /* Set it as current if it worked */
+ Context = &ApplicationExecutionContext;
+ CurrentExecutionContext = &ApplicationExecutionContext;
+ }
+
+ /* Initialize EFI mode */
+ EfiStatus = ArchInitializeContext(&FirmwareExecutionContext);
+ if (NT_SUCCESS(EfiStatus))
+ {
+ /* Set it as current if application context failed */
+ if (!NT_SUCCESS(AppStatus))
+ {
+ Context = &FirmwareExecutionContext;
+ CurrentExecutionContext = &FirmwareExecutionContext;
+ }
+
+ /* Switch to application mode, or EFI if that one failed */
+ ArchSwitchContext(Context, NULL);
+ EfiStatus = STATUS_SUCCESS;
+ }
+
+ /* Return initialization state */
+ return EfiStatus;
+}
+
+VOID
+BlpArchSwitchContext (
+ _In_ BL_ARCH_MODE NewMode
+ )
+{
+ PBL_ARCH_CONTEXT Context;
+
+ /* In real mode, use EFI, otherwise, use the application mode */
+ Context = &FirmwareExecutionContext;
+ if (NewMode != BlProtectedMode) Context = &ApplicationExecutionContext;
+
+ /* Are we in a different mode? */
+ if (CurrentExecutionContext->Mode != NewMode)
+ {
+ /* Switch to the new one */
+ ArchSwitchContext(Context, CurrentExecutionContext);
+ CurrentExecutionContext = Context;
+ }
+}
+
+/*++
+* @name BlpArchInitialize
+*
+* The BlpArchInitialize function initializes the Boot Library.
+*
+* @param Phase
+* Pointer to the Boot Application Parameter Block.
+*
+* @return NT_SUCCESS if the boot library was loaded correctly, relevant error
+* otherwise.
+*
+*--*/
+NTSTATUS
+BlpArchInitialize (
+ _In_ ULONG Phase
+ )
+{
+ KDESCRIPTOR Idtr;
+ USHORT CodeSegment;
+ NTSTATUS Status;
+ PKIDTENTRY IdtBase;
+
+ /* Assume success */
+ Status = STATUS_SUCCESS;
+
+ /* Is this phase 1? */
+ if (Phase != 0)
+ {
+ /* Get the IDT */
+ __sidt(&Idtr);
+ IdtBase = (PKIDTENTRY)Idtr.Base;
+
+ /* Get the Code Segment */
+ // _asm { mov CodeSegment, cs } FIXME: GCC
+ CodeSegment = 8; // fix fix
+
+ /* Set up INT 3, ASSERT, and SECURITY_ASSERT to be no-op (for Rtl) */
+ IdtBase[3].Offset = (USHORT)(ULONG_PTR)ArchTrapNoProcess;
+ IdtBase[3].Selector = CodeSegment;
+ IdtBase[3].Access = 0x8E00u;
+ IdtBase[3].ExtendedOffset = (ULONG_PTR)ArchTrapNoProcess >> 16;
+ IdtBase[0x2C].Offset = (USHORT)(ULONG_PTR)ArchTrapNoProcess;
+ IdtBase[0x2C].Selector = CodeSegment;
+ IdtBase[0x2C].Access = 0x8E00u;
+ IdtBase[0x2C].ExtendedOffset = (ULONG_PTR)ArchTrapNoProcess >> 16;
+ IdtBase[0x2D].Offset = (USHORT)(ULONG_PTR)ArchTrapNoProcess;
+ IdtBase[0x2D].Selector = CodeSegment;
+ IdtBase[0x2D].Access = 0x8E00u;
+ IdtBase[0x2D].ExtendedOffset = (ULONG_PTR)ArchTrapNoProcess >> 16;
+
+ /* Write the IDT back */
+ Idtr.Base = (ULONG)IdtBase;
+ __lidt(&Idtr);
+
+ /* Reset FPU state */
+ // __asm { fninit } FIXME: GCC
+ }
+ else
+ {
+ /* Reset TSC if needed */
+ if ((__readmsr(0x10) >> 32) & 0xFFC00000)
+ {
+ __writemsr(0x10, 0);
+ }
+
+ /* Initialize all the contexts */
+ Status = ArchInitializeContexts();
+ }
+
+ /* Return initialization state */
+ return Status;
+}
+
projects / reactos.git / blobdiff