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Posted: **Tue Jun 08, 2010 6:46 am**

Please help me.I have met something odd when I enable APIC timer.once I set IF flag,it always comes with GP error.I checked my CPL & DPL out ,CPL=0,DPL=0.But if I use 8259A timers,it's OK. No GP error any more.

Code: Select all

global G_IRQ_ENTRIES_START
extern G_Do_IRQ
extern _USER_DATA
extern _GDT_NULL
extern G_Enable_8259A_IRQ

%define NR_IRQS 224

%macro G_SAVE_ALL 0
 	cld
 	push es
 	push ds
 	push eax
 	push ebp
 	push edi
 	push esi
 	push edx
 	push ecx
 	push ebx
 	mov edx,_USER_DATA
 	sub edx,_GDT_NULL
 	mov ds,dx
 	mov es,dx
%endmacro

%macro G_RESTORE_INT_REG 0
	pop ebx
	pop ecx
	pop edx
	pop esi
	pop edi
	pop ebp
	pop eax
%endmacro

%macro G_RESTORE_REG 0
	G_RESTORE_INT_REG
	pop ds
	pop es

%endmacro
;;;interrupt 
G_IRQ_ENTRIES_START:
[BITS 32]
%assign vec 0
%rep NR_IRQS
ALIGN 16
push vec-256
jmp G_Common_Interrupt
%assign vec vec+1
%endrep
ALIGN 16
;;;Common Interrupt
G_Common_Interrupt:
	G_SAVE_ALL;it is same with SAVE ALL macro of Linux
 	mov eax,esp
	call G_Do_IRQ;G_Do_IRQ function is similar to Linux's _do_irq
	jmp G_Ret_From_Inter
;;;Ret From Inter
G_Ret_From_Inter:
	cli
	mov al,0
	out 0x21,al
G_RESTORE_ALL:
	pop ebx
	pop ecx
	pop edx
	pop esi
	pop edi
	pop ebp
	pop eax
	add esp,12
	iretd

Posted: **Thu Jun 10, 2010 10:35 pm**

have you mask all your interrupts of i8259A? if not, many strange things may happen. i met this before,that's the only problem.

Posted: **Sat Jun 12, 2010 2:37 am**

Thanks for your reply.APIC timer works after i mask all i8259A ints.

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APIC timer interrupter problem

APIC timer interrupter problem

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Re: APIC timer interrupter problem