PIC does not reset?

[DCNick3]

I have this timer ISR

Code: Select all

.global KiIRQ0Handler
.type KiIRQ0Handler, @function
KiTimerCounter:
	.long 0
KiItsTimeText:
	.string "It's time!~"
KiIRQ0Handler:

	addl $0x01, KiTimerCounter
	cmpl $3, KiTimerCounter
	jle KiIRQ0Handler_exit
	push $KiItsTimeText
	call KiFault

	KiIRQ0Handler_exit:
	push %eax
    # Here I'm performing PIC reset, but it looks like It's not resetted...
    # I can receive only one IRQ
	mov  $0x20, %al
	out  %al, $0x20
	pop  %eax
	iret

This being called only once? but I set up timer like this

Code: Select all

static VOID inline KiPortOutByte(WORD bPort, BYTE bValue)
{
	ASM VOLATILE ("mov %0, %%al; mov %1, %%dx; outb %%al, %%dx" : : "g"(bValue), "g"((WORD)bPort));
}

/* ......... */

KiPortOutByte(0x43, 0x33);
WORD wReloadValue = 65535;
KiPortOutByte(0x40, wReloadValue & 0xFF);
KiPortOutByte(0x40, (wReloadValue & 0xFF00) >> 8);

What am I doing wrong?

[heat]

Code: Select all

cmpl $3, KiTimerCounter
jle KiIRQ0Handler_exit

This seems odd, to say the least.

[DCNick3]

Code: Select all

cmpl $3, KiTimerCounter
jle KiIRQ0Handler_exit

This seems odd, to say the least.

Why it's odd?
It's checking if the counter is bigger than 3.
If yes - it runs KiFatal with argument - string "It's time!~"

P.S. I'm using QEMU debugger to determine, that ISR is called.

[heat]

Code: Select all

cmpl $3, KiTimerCounter
jle KiIRQ0Handler_exit

This seems odd, to say the least.

Why it's odd?
It's checking if the counter is bigger than 3.
If yes - it runs KiFatal with argument - string "It's time!~"

P.S. I'm using QEMU debugger to determine, that ISR is called.

Yes, you're right, my bad. Try replacing that iret for an 'iretd' or 'iretq'(iretq if you're in 64-bit mode).
PS: You also should want to add a 'cli' at the start of the IRQ handler

[DCNick3]

Code: Select all

cmpl $3, KiTimerCounter
jle KiIRQ0Handler_exit

This seems odd, to say the least.

Why it's odd?
It's checking if the counter is bigger than 3.
If yes - it runs KiFatal with argument - string "It's time!~"

P.S. I'm using QEMU debugger to determine, that ISR is called.

Yes, you're right, my bad. Try replacing that iret for an 'iretd' or 'iretq'(iretq if you're in 64-bit mode).
PS: You also should want to add a 'cli' at the start of the IRQ handler

Looks like GNU AS doesn't know instruction iretd, but iretl is ok.
Added cli, but all of this doesn't help =C

[heat]

Check if you're actually returning from the interrupt handler, for starters.

[DCNick3]

Check if you're actually returning from the interrupt handler, for starters.

Yes It returns, program continues to run, when I debug it step-by-step, it's successfully returns.

[iansjack]

You seem to be configuring the PIT in one-shot, BCD mode. I'm not sure that's what you want.

[DCNick3]

You seem to be configuring the PIT in one-shot, BCD mode. I'm not sure that's what you want.

Thanks a lot, I missed last bit of the command-code
UPD: But it still doesn't work =C
UPD2: It's alive, thanks a lot!