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#------------------------------------------------------------------------------
#*
#* Copyright 2006, Intel Corporation
#* All rights reserved. This program and the accompanying materials
#* are licensed and made available under the terms and conditions of the BSD License
#* which accompanies this distribution. The full text of the license may be found at
#* http://opensource.org/licenses/bsd-license.php
#*
#* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
#* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#*
#* CpuInterrupt.S
#*
#* Abstract:
#*
#------------------------------------------------------------------------------
#PUBLIC SystemTimerHandler
#PUBLIC SystemExceptionHandler
#EXTERNDEF mExceptionCodeSize:DWORD
#EXTERN TimerHandler: NEAR
#EXTERN ExceptionHandler: NEAR
#EXTERN mTimerVector: DWORD
.data
ASM_GLOBAL ASM_PFX(mExceptionCodeSize)
ASM_PFX(mExceptionCodeSize): .long 9
.text
ASM_GLOBAL ASM_PFX(InitDescriptor)
ASM_PFX(InitDescriptor):
movl $GDT_BASE,%eax # EAX=PHYSICAL address of gdt
movl %eax, gdtr + 2 # Put address of gdt into the gdtr
lgdt gdtr
movl $IDT_BASE,%eax # EAX=PHYSICAL address of idt
movl %eax, idtr + 2 # Put address of idt into the idtr
lidt idtr
ret
# VOID
# InstallInterruptHandler (
# UINTN Vector,
# VOID (*Handler)(VOID)
# )
ASM_GLOBAL ASM_PFX(InstallInterruptHandler)
ASM_PFX(InstallInterruptHandler):
# Vector:DWORD @ 4(%esp)
# Handler:DWORD @ 8(%esp)
push %edi
pushf # save eflags
cli # turn off interrupts
subl $6,%esp # open some space on the stack
movl %esp,%edi
sidt (%edi) # get fword address of IDT
movl 2(%edi), %edi # move offset of IDT into EDI
addl $6,%esp # correct stack
movl 12(%esp),%eax # Get vector number
shl $3,%eax # multiply by 8 to get offset
addl %eax,%edi # add to IDT base to get entry
movl 16(%esp),%eax # load new address into IDT entry
movw %ax,(%edi) # write bits 15..0 of offset
shrl $16,%eax # use ax to copy 31..16 to descriptors
movw %ax,6(%edi) # write bits 31..16 of offset
popf # restore flags (possible enabling interrupts)
pop %edi
ret
.macro JmpCommonIdtEntry
# jmp commonIdtEntry - this must be hand coded to keep the assembler from
# using a 8 bit reletive jump when the entries are
# within 255 bytes of the common entry. This must
# be done to maintain the consistency of the size
# of entry points...
.byte 0xe9 # jmp 16 bit reletive
.long commonIdtEntry - . - 4 # offset to jump to
.endm
.p2align 1
ASM_GLOBAL ASM_PFX(SystemExceptionHandler)
ASM_PFX(SystemExceptionHandler):
INT0:
pushl $0x0 # push error code place holder on the stack
pushl $0x0
JmpCommonIdtEntry
# db 0e9h # jmp 16 bit reletive
# dd commonIdtEntry - $ - 4 # offset to jump to
INT1:
pushl $0x0 # push error code place holder on the stack
pushl $0x1
JmpCommonIdtEntry
INT2:
pushl $0x0 # push error code place holder on the stack
pushl $0x2
JmpCommonIdtEntry
INT3:
pushl $0x0 # push error code place holder on the stack
pushl $0x3
JmpCommonIdtEntry
INT4:
pushl $0x0 # push error code place holder on the stack
pushl $0x4
JmpCommonIdtEntry
INT5:
pushl $0x0 # push error code place holder on the stack
pushl $0x5
JmpCommonIdtEntry
INT6:
pushl $0x0 # push error code place holder on the stack
pushl $0x6
JmpCommonIdtEntry
INT7:
pushl $0x0 # push error code place holder on the stack
pushl $0x7
JmpCommonIdtEntry
INT8:
# Double fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $0x8
JmpCommonIdtEntry
INT9:
pushl $0x0 # push error code place holder on the stack
pushl $0x9
JmpCommonIdtEntry
INT10:
# Invalid TSS causes an error code to be pushed so no phony push necessary
nop
nop
pushl $10
JmpCommonIdtEntry
INT11:
# Segment Not Present causes an error code to be pushed so no phony push necessary
nop
nop
pushl $11
JmpCommonIdtEntry
INT12:
# Stack fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $12
JmpCommonIdtEntry
INT13:
# GP fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $13
JmpCommonIdtEntry
INT14:
# Page fault causes an error code to be pushed so no phony push necessary
nop
nop
pushl $14
JmpCommonIdtEntry
INT15:
pushl $0x0 # push error code place holder on the stack
pushl $15
JmpCommonIdtEntry
INT16:
pushl $0x0 # push error code place holder on the stack
pushl $16
JmpCommonIdtEntry
INT17:
# Alignment check causes an error code to be pushed so no phony push necessary
nop
nop
pushl $17
JmpCommonIdtEntry
INT18:
pushl $0x0 # push error code place holder on the stack
pushl $18
JmpCommonIdtEntry
INT19:
pushl $0x0 # push error code place holder on the stack
pushl $19
JmpCommonIdtEntry
INTUnknown:
.rept (32 - 20)
pushl $0x0 # push error code place holder on the stack
# push xxh # push vector number
.byte 0x6a
.byte ( . - INTUnknown - 3 ) / 9 + 20 # vector number
JmpCommonIdtEntry
.endr
ASM_GLOBAL ASM_PFX(SystemTimerHandler)
ASM_PFX(SystemTimerHandler):
pushl $0
pushl $ASM_PFX(mTimerVector)
JmpCommonIdtEntry
commonIdtEntry:
# +---------------------+
# + EFlags +
# +---------------------+
# + CS +
# +---------------------+
# + EIP +
# +---------------------+
# + Error Code +
# +---------------------+
# + Vector Number +
# +---------------------+
# + EBP +
# +---------------------+ <-- EBP
cli
push %ebp
movl %esp,%ebp
#
# Align stack to make sure that EFI_FX_SAVE_STATE_IA32 of EFI_SYSTEM_CONTEXT_IA32
# is 16-byte aligned
#
andl $0xfffffff0,%esp
subl $12,%esp
## UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax#
push %eax
push %ecx
push %edx
push %ebx
leal 6*4(%ebp),%ecx
push %ecx # ESP
push (%ebp) # EBP
push %esi
push %edi
## UINT32 Gs, Fs, Es, Ds, Cs, Ss#
movw %ss,%ax
push %eax
movzx 4*4(%ebp),%eax
push %eax
movw %ds,%ax
push %eax
movw %es,%ax
push %eax
movw %fs,%ax
push %eax
movw %gs,%ax
push %eax
## UINT32 Eip#
pushl 3*4(%ebp)
## UINT32 Gdtr[2], Idtr[2]#
subl $8,%esp
sidt (%esp)
subl $8,%esp
sgdt (%esp)
## UINT32 Ldtr, Tr#
xorl %eax, %eax
str %ax
push %eax
sldt %eax
push %eax
## UINT32 EFlags#
pushl 5*4(%ebp)
## UINT32 Cr0, Cr1, Cr2, Cr3, Cr4#
mov %cr4,%eax
orl $0x208,%eax
mov %eax,%cr4
push %eax
mov %cr3,%eax
push %eax
mov %cr2,%eax
push %eax
xor %eax, %eax
push %eax
mov %cr0,%eax
push %eax
## UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7#
mov %dr7,%eax
push %eax
## clear Dr7 while executing debugger itself
xor %eax, %eax
mov %eax,%dr7
mov %dr6,%eax
push %eax
## insure all status bits in dr6 are clear...
xor %eax, %eax
mov %eax,%dr6
mov %dr3,%eax
push %eax
mov %dr2,%eax
push %eax
mov %dr1,%eax
push %eax
mov %dr0,%eax
push %eax
## FX_SAVE_STATE_IA32 FxSaveState;
sub $512,%esp
mov %esp,%edi
fxsave (%edi)
## UINT32 ExceptionData;
pushl 2*4(%ebp)
## Prepare parameter and call
mov %esp,%edx
push %edx
mov 1*4(%ebp),%eax
push %eax
cmpl $32,%eax
jb CallException
call ASM_PFX(TimerHandler)
jmp ExceptionDone
CallException:
call ASM_PFX(ExceptionHandler)
ExceptionDone:
addl $8,%esp
cli
## UINT32 ExceptionData;
addl $4,%esp
## FX_SAVE_STATE_IA32 FxSaveState;
mov %esp,%esi
fxrstor (%esi)
addl $512,%esp
#; UINT32 Dr0, Dr1, Dr2, Dr3, Dr6, Dr7;
pop %eax
mov %eax,%dr0
pop %eax
mov %eax,%dr1
pop %eax
mov %eax,%dr2
pop %eax
mov %eax,%dr3
## skip restore of dr6. We cleared dr6 during the context save.
addl $4,%esp
pop %eax
mov %eax,%dr7
## UINT32 Cr0, Cr1, Cr2, Cr3, Cr4;
pop %eax
mov %eax,%cr0
addl $4,%esp # not for Cr1
pop %eax
mov %eax,%cr2
pop %eax
mov %eax,%cr3
pop %eax
mov %eax,%cr4
## UINT32 EFlags;
popl 5*4(%ebp)
## UINT32 Ldtr, Tr;
## UINT32 Gdtr[2], Idtr[2];
## Best not let anyone mess with these particular registers...
addl $24,%esp
## UINT32 Eip;
popl 3*4(%ebp)
## UINT32 Gs, Fs, Es, Ds, Cs, Ss;
## NOTE - modified segment registers could hang the debugger... We
## could attempt to insulate ourselves against this possibility,
## but that poses risks as well.
##
pop %gs
pop %fs
pop %es
pop %ds
popl 4*4(%ebp)
pop %ss
## UINT32 Edi, Esi, Ebp, Esp, Ebx, Edx, Ecx, Eax;
pop %edi
pop %esi
addl $4,%esp # not for ebp
addl $4,%esp # not for esp
pop %ebx
pop %edx
pop %ecx
pop %eax
mov %ebp,%esp
pop %ebp
addl $8,%esp
iret
#;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
# data
#;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.data
.p2align 2
gdtr: .short GDT_END - GDT_BASE - 1 # GDT limit
.long 0 # (GDT base gets set above)
#;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
# global descriptor table (GDT)
#;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
.p2align 2
GDT_BASE:
# null descriptor
NULL_SEL = .-GDT_BASE
.short 0 # limit 15:0
.short 0 # base 15:0
.byte 0 # base 23:16
.byte 0 # type
.byte 0 # limit 19:16, flags
.byte 0 # base 31:24
# linear data segment descriptor
LINEAR_SEL = .-GDT_BASE
.short 0x0FFFF # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0x092 # present, ring 0, data, expand-up, writable
.byte 0x0CF # page-granular, 32-bit
.byte 0
# linear code segment descriptor
LINEAR_CODE_SEL = .-GDT_BASE
.short 0x0FFFF # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0x09A # present, ring 0, data, expand-up, writable
.byte 0x0CF # page-granular, 32-bit
.byte 0
# system data segment descriptor
SYS_DATA_SEL = .-GDT_BASE
.short 0x0FFFF # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0x092 # present, ring 0, data, expand-up, writable
.byte 0x0CF # page-granular, 32-bit
.byte 0
# system code segment descriptor
SYS_CODE_SEL = .-GDT_BASE
.short 0x0FFFF # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0x09A # present, ring 0, data, expand-up, writable
.byte 0x0CF # page-granular, 32-bit
.byte 0
# spare segment descriptor
SPARE3_SEL = .-GDT_BASE
.short 0 # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0 # present, ring 0, data, expand-up, writable
.byte 0 # page-granular, 32-bit
.byte 0
# spare segment descriptor
SPARE4_SEL = .-GDT_BASE
.short 0 # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0 # present, ring 0, data, expand-up, writable
.byte 0 # page-granular, 32-bit
.byte 0
# spare segment descriptor
SPARE5_SEL = .-GDT_BASE
.short 0 # limit 0xFFFFF
.short 0 # base 0
.byte 0
.byte 0 # present, ring 0, data, expand-up, writable
.byte 0 # page-granular, 32-bit
.byte 0
GDT_END:
.p2align 2
idtr: .short IDT_END - IDT_BASE - 1 # IDT limit
.long 0 # (IDT base gets set above)
#;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
# interrupt descriptor table (IDT)
#
# Note: The hardware IRQ's specified in this table are the normal PC/AT IRQ
# mappings. This implementation only uses the system timer and all other
# IRQs will remain masked. The descriptors for vectors 33+ are provided
# for convenience.
#;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
#idt_tag .byte "IDT",0
.p2align 2
IDT_BASE:
# divide by zero (INT 0)
DIV_ZERO_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# debug exception (INT 1)
DEBUG_EXCEPT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# NMI (INT 2)
NMI_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# soft breakpoint (INT 3)
BREAKPOINT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# overflow (INT 4)
OVERFLOW_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# bounds check (INT 5)
BOUNDS_CHECK_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# invalid opcode (INT 6)
INVALID_OPCODE_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# device not available (INT 7)
DEV_NOT_AVAIL_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# double fault (INT 8)
DOUBLE_FAULT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# Coprocessor segment overrun - reserved (INT 9)
RSVD_INTR_SEL1 = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# invalid TSS (INT 0ah)
INVALID_TSS_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# segment not present (INT 0bh)
SEG_NOT_PRESENT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# stack fault (INT 0ch)
STACK_FAULT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# general protection (INT 0dh)
GP_FAULT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# page fault (INT 0eh)
PAGE_FAULT_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# Intel reserved - do not use (INT 0fh)
RSVD_INTR_SEL2 = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# floating point error (INT 0x10)
FLT_POINT_ERR_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # type = 386 interrupt gate, present
.short 0 # offset 31:16
# alignment check (INT 0x11)
ALIGNMENT_CHECK_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# machine check (INT 0x12)
MACHINE_CHECK_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# SIMD floating-point exception (INT 0x13)
SIMD_EXCEPTION_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
.rept (32 - 20)
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
.endr
# 72 unspecified descriptors
.fill 72 * 8, 1, 0
# IRQ 0 (System timer) - (INT 0x68)
IRQ0_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 1 (8042 Keyboard controller) - (INT 0x69)
IRQ1_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# Reserved - IRQ 2 redirect (IRQ 2) - DO NOT USE!!! - (INT 6ah)
IRQ2_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 3 (COM 2) - (INT 6bh)
IRQ3_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 4 (COM 1) - (INT 6ch)
IRQ4_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 5 (LPT 2) - (INT 6dh)
IRQ5_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 6 (Floppy controller) - (INT 6eh)
IRQ6_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 7 (LPT 1) - (INT 6fh)
IRQ7_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 8 (RTC Alarm) - (INT 0x70)
IRQ8_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 9 - (INT 0x71)
IRQ9_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 10 - (INT 0x72)
IRQ10_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 11 - (INT 0x73)
IRQ11_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 12 (PS/2 mouse) - (INT 0x74)
IRQ12_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 13 (Floating point error) - (INT 0x75)
IRQ13_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 14 (Secondary IDE) - (INT 0x76)
IRQ14_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
# IRQ 15 (Primary IDE) - (INT 0x77)
IRQ15_SEL = .-IDT_BASE
.short 0 # offset 15:0
.short SYS_CODE_SEL # selector 15:0
.byte 0 # 0 for interrupt gate
.byte 0x0e | 0x80 # (10001110)type = 386 interrupt gate, present
.short 0 # offset 31:16
.fill 1 * 8, 1, 0
IDT_END:
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