[linuxdc-dev]AICA interrupts

[Adrian M. <ad...@mc...>]

I am experimenting with the AICA interrupt - HW_EVENT_AICA_SYS - but I am 
getting odd results:

This is the request call:

request_irq(HW_EVENT_AICA_SYS, aica_interrupt_handler, SA_INTERRUPT, "AICA", 
NULL);

And this is the (very simple!) handler:

////////////////////////////////////////////////////////////////
// Experimental interrupt handler                             //
////////////////////////////////////////////////////////////////

void aica_interrupt_handler(int i, void* p, struct pt_regs * ptr)
{
  
}


This is triggered thus:

static ssize_t aica_audio_write(struct file *file, const char *buffer,
				size_t count, loff_t * ppos)
{
	if (count < 1)
		return 0;

	//enable aica interrupts
	writel(0x20, 0xa07028b4);
	spu_write_wait();
	ssize_t ret;
	ret = aica_audio_do_write(file, buffer, count, ppos);
	writel(0x20, 0xa07028b8);
	spu_write_wait();
	//turn off aica interrupts
	writel(0x20, 0xa07028bc);

	spu_write_wait();
	return ret;

}

When this runs every call to writel(0x20, 0xa07028b8) appears to generate 
"unexpected IRQ trap at vector 0b" (though system output otherwise is normal).

What have I done wrong?

Adrian