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lloader.386
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;***************************************************************************
;
; Copyright (c) 1997, 1998 Timpanogas Research Group, Inc. All Rights
; Reserved.
;
; AUTHOR : Jeff V. Merkey
; FILE : LLOADER.386
; DESCRIP : Protected Mode Loader Code for MANOS v1.0
; DATE : November 12, 1997
;
;
;***************************************************************************
.486P ; select the processor
model flat
include dos.inc
include ia32.inc
PS2 EQU 4
EXCEPTION_ENTRIES EQU 19
RESUME_FLAG EQU 00010000h
NESTED_TASK_FLAG EQU 00004000h
SINGLE_STEP_FLAG EQU 00000100h
OperSize macro
db 66h
endm
AddrSize macro
db 67h
endm
Synch macro
LOCAL L1, L2, L3
jmp short L1
L1:
jmp short L2
L2:
jmp short L3
L3:
endm
CGROUP GROUP _TEXT
DGROUP GROUP _DATA
ASSUME cs:_TEXT, ds:_DATA, es:_DATA, fs:_DATA
_DATA SEGMENT PUBLIC USE32 'DATA'
align 16
public DOSDataTable
DOSDataTable dd 0
align 16
public debug_stack
debug_stack db 100h dup (0)
debug_stack_top label dword
align 16
public debug_NMIstack
debug_NMIstack db 100h dup (0)
debug_NMIstack_top label dword
align 16
public debug_DFstack
debug_DFstack db 100h dup (0)
debug_DFstack_top label dword
align 16
public initial_stack
initial_stack db 200h dup (0)
initial_stack_top label dword
align 16
public ProcessorTaskIndex
ProcessorTaskIndex dd 0
align 16
public ExceptionTaskIndex
ExceptionTaskIndex dd EXCEPTION_ENTRIES dup (0)
align 16
public ProcessorSegmentTable
ProcessorSegmentTable dd 0
align 16
public ExceptionSegmentTable
ExceptionSegmentTable dd EXCEPTION_ENTRIES dup (0)
align 16
public HandlerTable
HandlerTable dd DivideError ;0
dd DebuggerInt1 ;1
dd NMI ;2
dd DebuggerInt3 ;3
dd Overflow ;4
dd BoundsCheck ;5
dd InvalidOpcode ;6
dd NoCoprocessor ;7
dd DoubleFault ;8
dd Cops ;9
dd TSSCheck ;10
dd SegmentNotPresent ;11
dd StackException ;12
dd GeneralProtection ;13
dd PageFault ;14
dd InvalidInterrupt ;15
dd CoProcessorError ;16
dd AlignmentCheck ;17
dd MachineCheck ;18
dd InvalidInterrupt ;19
dd InvalidInterrupt ;20
dd InvalidInterrupt ;21
dd InvalidInterrupt ;22
dd InvalidInterrupt ;23
dd InvalidInterrupt ;24
dd InvalidInterrupt ;25
dd InvalidInterrupt ;26
dd InvalidInterrupt ;27
dd InvalidInterrupt ;28
dd InvalidInterrupt ;29
dd InvalidInterrupt ;30
dd InvalidInterrupt ;31
dd InvalidInterrupt ;32
dd InvalidInterrupt ;33
dd InvalidInterrupt ;34
dd InvalidInterrupt ;35
dd InvalidInterrupt ;36
dd InvalidInterrupt ;37
dd InvalidInterrupt ;38
dd InvalidInterrupt ;39
dd HW0 ;40 / 28h
dd HW1 ;41
dd HW2 ;42
dd HW3 ;43
dd HW4 ;44
dd HW5 ;45
dd HW6 ;46
dd HW7 ;47
dd InvalidInterrupt ;48
dd InvalidInterrupt ;49
dd InvalidInterrupt ;50
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;60
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;70
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd SpuriousVector ;79 / 4Fh
dd InvalidInterrupt ;80
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;90
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;100
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;110
dd InvalidInterrupt
dd HW8 ;112
dd HW9 ;113
dd HW10 ;114
dd HW11 ;115
dd HW12 ;116
dd HW13 ;117
dd HW14 ;118
dd HW15 ;119
dd InvalidInterrupt ;120
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd HW16 ;130
dd HW17
dd HW18
dd HW19
dd HW20
dd HW21
dd HW22
dd HW23
dd HW24
dd HW25
dd HW26 ;140
dd HW27
dd HW28
dd HW29
dd HW30
dd HW31
dd HW32
dd HW33
dd HW34
dd HW35
dd HW36 ;150
dd HW37
dd HW38
dd HW39
dd HW40
dd HW41
dd HW42
dd HW43
dd HW44
dd HW45
dd HW46 ;160
dd HW47
dd HW48
dd HW49
dd HW50
dd HW51
dd HW52
dd HW53
dd HW54
dd HW55
dd HW56
dd HW57 ;170
dd HW58
dd HW59
dd HW60
dd HW61
dd HW62
dd HW63
dd HW64
dd HW65
dd InvalidInterrupt ;180
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;190
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;200
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;210
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;220
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;230
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;240
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt ;250
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
dd InvalidInterrupt
HandlerTableEnd label dword
SystemIDTEntryNumber equ ((HandlerTableEnd - HandlerTable) / 4)
align 16
public ProcessorIDT0
ProcessorIDT0 label word
rept EXCEPTION_ENTRIES
TSSGate <>
endm
rept (SystemIDTEntryNumber - EXCEPTION_ENTRIES)
IDTDescriptor <>
endm
align 16
public ProcessorIDTTable0
ProcessorIDTTable0 label pword
dw (SystemIDTEntryNumber * 8)
dd ProcessorIDT0
align 16
public SystemIDTTable
SystemIDTTable label pword
SystemIDTIndex dw 0
SystemIDTOffset dd 0
align 16
public IDTSegments
IDTSegments label dword
IDTSegmentTable dd ProcessorIDT0
IDTSegmentsEnd label dword
NumberOfIDTTables EQU ((IDTSegmentsEnd - IDTSegments) / 4)
align 16
public IDTPointers
IDTPointers label dword
IDTPointerTable dd ProcessorIDTTable0
IDTPointersEnd label dword
NumberOfIDTPointers EQU ((IDTPointersEnd - IDTPointers) / 4)
align 16
public StartOfSystemGDT
StartOfSystemGDT label dword
public pNullGDT
pNullGDT GDTDescriptor <> ; 00h
pCodeSegment GDTDescriptor <,,,9Ah> ; 08h
pDataSegment GDTDescriptor <> ; 10h
pRealModeCode GDTDescriptor <,,,9Ah,0> ; 18h
pRealModeData GDTDescriptor <,,,,0> ; 20h
pBIOSCode GDTDescriptor <,,,9Ah,0C0h> ; 28h
pBIOSData GDTDescriptor <,,,,0C0h> ; 30h
pRealIntCode GDTDescriptor <,,,9Ah,0> ; 38h
pRealIntData GDTDescriptor <,,,,0> ; 40h
public TSSDefaultDescriptors ; starts at 48h
TSSDefaultDescriptors label dword
TSSDescriptor <>
public TSSDescriptors
TSSDescriptors label dword
rept EXCEPTION_ENTRIES
TSSDescriptor <>
endm
EndOfSystemGDT label dword
public TSSDefaultSegments
TSSDefaultSegments label dword
TaskStateSegment <>
public TSSSegments
TSSSegments label dword
rept EXCEPTION_ENTRIES
TaskStateSegment <>
endm
SystemGDTSize EQU (EndOfSystemGDT - StartOfSystemGDT)
TSSDefaultSegmentIndex EQU (TSSDefaultDescriptors - StartOfSystemGDT)
TSSSegmentIndex EQU (TSSDescriptors - StartOfSystemGDT)
align 16
public SystemGDTTable
SystemGDTTable label pword
SystemGDTIndex dw SystemGDTSize
SystemGDTOffset dd pNullGDT
align 16
saved_stack dd 0
align 16
RealModeStack db 400h dup (0)
RealModeStackTop db 100h dup (0)
align 16
savedPaging dd 0
align 16
SavePagingStack db 400h dup (0)
SavePagingStackTop db 100h dup (0)
_DATA ENDS
_TEXT SEGMENT PUBLIC USE32 'CODE'
ASSUME cs:_TEXT, ds:_DATA, es:_DATA, fs:_DATA
extrn loader_main: near
extrn ExitLoader: near
save_context macro
push eax
push ebx
push ecx
push edx
push ebp
push esi
push edi
push ds
push es
push fs
endm
restore_context macro
pop fs
pop es
pop ds
pop edi
pop esi
pop ebp
pop edx
pop ecx
pop ebx
pop eax
iretd
endm
;
; TSS entry code
;
task_entry macro
LOCAL @TSSNotNested, @NoLTR
cli
xor eax, eax
str ax
mov esi, offset SystemGDTTable
mov esi, dword ptr [esi + 2]
lea ebx, [esi + eax]
mov al, [ebx].TSSBase2
mov ah, [ebx].TSSBase3
shl eax, 16
mov ax, [ebx].TSSBase1
;
; eax -> TSS Segment (Current)
; ebx -> TSS Descriptor (Current)
;
movzx ecx, word ptr [eax].tBackLink
or ecx, ecx
jz @TSSNotNested
mov esi, offset SystemGDTTable
mov esi, dword ptr [esi + 2]
lea edx, [esi + ecx]
mov cl, [edx].TSSBase2
mov ch, [edx].TSSBase3
shl ecx, 16
mov cx, [edx].TSSBase1
mov ebp, ecx
;
; edx -> TSS Descriptor (Previous)
; ebp -> TSS Segment (Previous)
;
; clear busy state and reset TSS
;
mov [edx].TSSType, 10001001b
@TSSNotNested:
mov [ebx].TSSType, 10001001b
lgdt ds: SystemGDTTable ; reset GDT TSS Busy bit
movzx eax, word ptr [eax].tBackLink
or eax, eax
jz @NoLTR
ltr ax
@NoLTR:
mov eax, CR0
and eax, 0FFFFFFF7h ; clear task switch bit in CR0 to
mov CR0, eax ; avoid NPX exceptions
xor eax, eax
mov dr7, eax ; disable breakpoints
pushfd
and dword ptr [esp], NOT (NESTED_TASK_FLAG OR SINGLE_STEP_FLAG)
or dword ptr [esp], RESUME_FLAG
popfd
push ebp ; pass the TSS
endm
;
; TSS exit code
;
task_exit macro
pop ebp
mov gs, [ebp].tGS
mov fs, [ebp].tFS
mov ss, [ebp].tSS
mov es, [ebp].tES
mov ds, [ebp].tDS
mov edi, [ebp].tEDI
mov esi, [ebp].tESI
mov edx, [ebp].tEDX
mov ecx, [ebp].tECX
mov ebx, [ebp].tEBX
mov eax, [ebp].tEAX
mov esp, [ebp].tESP
push [ebp].tSystemFlags
push dword ptr [ebp].tCS
push [ebp].tEIP
mov ebp, [ebp].tEBP ; ebp is the last register we restore
iretd
endm
RDMSR macro
db 0Fh
db 30h
endm
WRMSR macro
db 0Fh
db 32h
endm
public MANOSStartup
MANOSStartup proc
cli
mov DOSDataTable, ebx
mov esp, offset initial_stack_top ; get protected mode stack
;
; initialize the processor IDT Tables
; init the IDT Table from the handler table
;
mov esi, offset HandlerTable
mov edi, offset ProcessorIDT0
mov ecx, SystemIDTEntryNumber
IDTLoop0:
movsw
add edi, 4
movsw
loop IDTLoop0
xor ebx, ebx
mov edx, TSSDefaultSegmentIndex
mov esi, offset TSSDefaultDescriptors ; default processor
mov edi, offset TSSDefaultSegments ; TSS segments and descriptors
InitializeNextDefaultTSSSegment:
mov ProcessorSegmentTable[ebx * 4], edi
mov ProcessorTaskIndex[ebx * 4], edx
mov eax, edi ; put the actual address of the TSS
mov [esi].TSSBase1, ax ; segment into the TSS descriptor
shr eax, 16 ; in the GDT
mov [esi].TSSBase2, al
mov [esi].TSSBase3, ah
mov eax, offset initial_stack_top
mov [edi].tESP0, eax ; initialize the fields
mov [edi].tESP1, eax ; of the TSS
mov [edi].tESP2, eax ;
mov [edi].tESP, eax
mov ax, 10h ; data selector 0010:00000000
mov [edi].tSS0, ax
mov [edi].tSS1, ax
mov [edi].tSS2, ax
mov [edi].tSS, ax
mov [edi].tDS, ax
mov [edi].tES, ax
mov [edi].tFS, ax
mov [edi].tGS, ax
mov [edi].tEBP, 0
mov [edi].tEBX, 0
mov [edi].tEAX, 0
mov [edi].tESI, 0
mov [edi].tEDI, 0
mov ax, 8h ; code selector 0008:00000000
mov [edi].tCS, ax
mov eax, offset loader_main
mov [edi].tEIP, eax
;
;
;
xor ebx, ebx
xor ebp, ebp
mov edx, TSSSegmentIndex
mov esi, offset TSSDescriptors
mov edi, offset TSSSegments
mov ecx, EXCEPTION_ENTRIES ; get number of segments
InitializeNextExceptionTSSSegment:
mov ExceptionSegmentTable[ebp * 4], edi
mov ExceptionTaskIndex[ebp * 4], edx
mov eax, edi
mov [esi].TSSBase1, ax
shr eax, 16
mov [esi].TSSBase2, al
mov [esi].TSSBase3, ah
cmp ebx, 2
je SetNMIStack
cmp ebx, 8
je SetDFStack
mov eax, offset debug_stack_top
mov [edi].tESP0, eax
jmp debugStackSet
SetNMIStack:
mov eax, offset debug_NMIstack_top
mov [edi].tESP0, eax
jmp debugStackSet
SetDFStack:
mov eax, offset debug_DFstack_top
mov [edi].tESP0, eax
jmp debugStackSet
debugStackSet:
mov [edi].tESP1, eax
mov [edi].tESP2, eax
mov [edi].tESP, eax
mov ax, 10h ; data selector 0010:00000000
mov [edi].tSS0, ax
mov [edi].tSS1, ax
mov [edi].tSS2, ax
mov [edi].tSS, ax
mov [edi].tDS, ax
mov [edi].tES, ax
mov [edi].tFS, ax
mov [edi].tGS, ax
mov [edi].tEBP, 0
mov [edi].tEBX, 0
mov [edi].tEAX, 0
mov [edi].tESI, 0
mov [edi].tEDI, 0
mov ax, 8h ; code selector 0008:00000000
mov [edi].tCS, ax
mov eax, HandlerTable[ebx * 4] ; get exception entry point
mov [edi].tEIP, eax
add esi, SIZE TSSDescriptor
add edi, SIZE TaskStateSegment
add edx, 8h ; bump GDT offset
inc ebx
inc ebp
dec ecx ; init next segment
or ecx, ecx
jnz InitializeNextExceptionTSSSegment
;
;
;
xor edx, edx ; zero Task Gate Selector
mov esi, offset ProcessorIDT0
mov ecx, EXCEPTION_ENTRIES
patch_idt_tables0:
mov [esi].TSSRes1, 0
mov eax, ExceptionTaskIndex[edx * 4] ; task gate index
mov [esi].TSSSelector, ax
mov [esi].TSSRes2, 0
mov [esi].TSSFlags, 10000101b
mov [esi].TSSRes3, 0
add esi, SIZE IDTDescriptor
inc edx ; bump Task Gate Selector
loop patch_idt_tables0
lidt ProcessorIDTTable0
load_gdt:
;
; create a relative 16-bit segment in the GDT Table
;
mov ebx, DOSDataTable
mov eax, [ebx].tJUMP16_SEGMENT
mov ebx, offset pRealModeCode
mov [ebx].Base1, ax
shr eax, 16
mov [ebx].Base2, al
mov [ebx].Base3, ah
mov ebx, DOSDataTable
mov eax, [ebx].tJUMP16_SEGMENT
mov ebx, offset pRealModeData
mov [ebx].Base1, ax
shr eax, 16
mov [ebx].Base2, al
mov [ebx].Base3, ah
mov eax, offset StartOfRealModeSegment
mov ebx, DOSDataTable
mov [ebx].tREAL_INT_SEGMENT, eax
mov ebx, offset pRealIntCode
mov [ebx].Base1, ax
shr eax, 16
mov [ebx].Base2, al
mov [ebx].Base3, ah
mov eax, offset StartOfRealModeSegment
mov ebx, DOSDataTable
mov [ebx].tREAL_INT_SEGMENT, eax
mov ebx, offset pRealIntData
mov [ebx].Base1, ax
shr eax, 16
mov [ebx].Base2, al
mov [ebx].Base3, ah
mov eax, offset int86x_jump_16
sub eax, offset StartOfRealModeSegment
mov int86x_jump_label, eax
mov eax, offset int86x_real_jump
xor ebx, ebx
mov ebx, eax
and ebx, 0Fh
shr eax, 4
shl eax, 16
mov ax, bx
mov int86x_real_jump_label, eax
lgdt SystemGDTTable ; load the new gdt
mov ax, 10h ; reload selectors
mov ss, ax
mov ds, ax
mov es, ax
mov fs, ax
mov gs, ax
; clear TSS busy bit and reload task register
mov eax, ProcessorTaskIndex[0 * 4]
mov esi, offset SystemGDTTable
mov esi, dword ptr [esi + 2]
lea ebx, [esi + eax]
mov [ebx].TSSType, 10001001b ; clear the busy bit
ltr ax
pushfd
and dword ptr [esp], NOT 4000h ; clear nested task flag
popfd
mov eax, DOSDataTable
push eax
call loader_main
add esp, 4
jmp ExitToDOS
public ExitToDOS
ExitToDOS:
mov ebx, DOSDataTable
mov eax, [ebx].tDOS_STACK_OFFSET
mov esp, eax
mov edx, [ebx].tDOS_DATA_SEGMENT ; restore ds:
mov eax, 20h
jmp ds: [ebx].tDOS_EXIT
hlt
align 16
public OSMain
OSMain:
cli
mov eax, [esp + 12] ; Code Segment in High Memory
mov ecx, [esp + 8] ; PM Table
mov ebx, [esp + 4] ; DOS Data Table
jmp eax
MANOSStartup endp
align 16
DivideError:
DebuggerInt1:
NMI:
DebuggerInt3:
Overflow:
BoundsCheck:
InvalidOpcode:
NoCoprocessor:
DoubleFault:
Cops:
TSSCheck:
SegmentNotPresent:
StackException:
GeneralProtection:
PageFault:
InvalidInterrupt:
CoProcessorError:
AlignmentCheck:
MachineCheck:
task_entry
jmp ExitLoader
align 16
HW0:
HW1:
HW2:
HW3:
HW4:
HW5:
HW6:
HW7:
push edx
push eax
mov edx, 20h
mov eax, 20h
out dx, al
pop eax
pop edx
iretd
HW8:
HW9:
HW10:
HW11:
HW12:
HW13:
HW14:
HW15:
push edx
push eax
mov edx, 0A0h
mov eax, 20h
out dx, al
mov edx, 20h
mov eax, 20h
out dx, al
pop eax
pop edx
iretd
HW16:
HW17:
HW18:
HW19:
HW20:
HW21:
HW22:
HW23:
HW24:
HW25:
HW26:
HW27:
HW28:
HW29:
HW30:
HW31:
HW32:
HW33:
HW34:
HW35:
HW36:
HW37:
HW38:
HW39:
HW40:
HW41:
HW42:
HW43:
HW44:
HW45:
HW46:
HW47:
HW48:
HW49:
HW50:
HW51:
HW52:
HW53:
HW54:
HW55:
HW56:
HW57:
HW58:
HW59:
HW60:
HW61:
HW62:
HW63:
HW64:
HW65:
SpuriousVector:
iretd
align 16
StartOfRealModeSegment label dword
align 16
OldPic db 0
db 0
db 0
db 0
align 16
OldIDT dp 0