315 lines
8.9 KiB
C

/** @file
C based implementation of IA32 interrupt handling only
requiring a minimal assembly interrupt entry point.
Copyright (c) 2006 - 2021, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include "CpuDxe.h"
#include "CpuGdt.h"
//
// Global descriptor table (GDT) Template
//
STATIC GDT mGdtTemplate = {
.Null = {
.SegmentLimit_15_0 = 0x0,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Type = 0x0,
.S = 0,
.DPL = 0,
.P = 0,
.SegmentLimit_19_16 = 0x0,
.AVL = 0,
.L = 0,
.D_B = 0,
.G = 0,
.BaseAddress_31_24 = 0x0
},
.Linear = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 0,
.Writable = 1,
.ExpansionDirection = 0,
.IsCode = 0,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.UpperBound = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.LinearCode = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 1,
.Readable = 1,
.Conforming = 1,
.IsCode = 1,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.Is32Bit = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.SysCode = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 0,
.Readable = 1,
.Conforming = 0,
.IsCode = 1,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.Is32Bit = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.SysData = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 1,
.Writable = 1,
.ExpansionDirection = 0,
.IsCode = 0,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.UpperBound = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.Ring3Code32 = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 0,
.Readable = 1,
.Conforming = 0,
.IsCode = 1,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 3,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.Is32Bit = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.Ring3Data32 = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 1,
.Writable = 1,
.ExpansionDirection = 0,
.IsCode = 0,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 3,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.UpperBound = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.SysCode16 = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 0,
.Readable = 1,
.Conforming = 0,
.IsCode = 1,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.Is32Bit = 0,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.LinearCode64 = {
.Reserved1 = 0x0,
.Reserved2 = 0x0,
.Accessed = 0,
.Readable = 1,
.Conforming = 0,
.IsCode = 1,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.Reserved3 = 0x0,
.Available = 0,
.LongMode = 1,
.Is32Bit = 0,
.Granularity = 1,
.Reserved4 = 0x0
},
.LinearData64 = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 0,
.Writable = 1,
.ExpansionDirection = 0,
.IsCode = 0,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 0,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.UpperBound = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.Spare5 = {
.SegmentLimit_15_0 = 0x0,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Type = 0x0,
.S = 0,
.DPL = 0,
.P = 0,
.SegmentLimit_19_16 = 0x0,
.AVL = 0,
.L = 0,
.D_B = 0,
.G = 0,
.BaseAddress_31_24 = 0x0,
},
.Ring3Data64 = {
.SegmentLimit_15_0 = 0xFFFF,
.BaseAddress_15_0 = 0x0,
.BaseAddress_23_16 = 0x0,
.Accessed = 0,
.Writable = 1,
.ExpansionDirection = 0,
.IsCode = 0,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 3,
.SegmentPresent = 1,
.SegmentLimit_19_16 = 0xF,
.Available = 0,
.Reserved = 0,
.UpperBound = 1,
.Granularity = 1,
.BaseAddress_31_24 = 0x0
},
.Ring3Code64 = {
.Reserved1 = 0x0,
.Reserved2 = 0x0,
.Accessed = 0,
.Readable = 1,
.Conforming = 0,
.IsCode = 1,
.IsNotSystemSegment = 1,
.DescriptorPrivilegeLevel = 3,
.SegmentPresent = 1,
.Reserved3 = 0x0,
.Available = 0,
.LongMode = 1,
.Is32Bit = 0,
.Granularity = 1,
.Reserved4 = 0x0
},
};
/**
Initialize Global Descriptor Table.
**/
VOID
InitGlobalDescriptorTable (
VOID
)
{
EFI_STATUS Status;
GDT *Gdt;
IA32_DESCRIPTOR Gdtr;
EFI_PHYSICAL_ADDRESS Memory;
//
// Allocate Runtime Data below 4GB for the GDT
// AP uses the same GDT when it's waken up from real mode so
// the GDT needs to be below 4GB.
//
Memory = SIZE_4GB - 1;
Status = gBS->AllocatePages (
AllocateMaxAddress,
EfiRuntimeServicesData,
EFI_SIZE_TO_PAGES (sizeof (mGdtTemplate)),
&Memory
);
ASSERT_EFI_ERROR (Status);
ASSERT ((Memory != 0) && (Memory < SIZE_4GB));
Gdt = (GDT *)(UINTN)Memory;
//
// Initialize all GDT entries
//
CopyMem (Gdt, &mGdtTemplate, sizeof (mGdtTemplate));
//
// Write GDT register
//
Gdtr.Base = (UINT32)(UINTN)Gdt;
Gdtr.Limit = (UINT16)(sizeof (mGdtTemplate) - 1);
AsmWriteGdtr (&Gdtr);
//
// Update selector (segment) registers base on new GDT
//
SetCodeSelector ((UINT16)CPU_CODE_SEL);
SetDataSelectors ((UINT16)CPU_DATA_SEL);
}