[Qemu-devel] Re: [PATCH 2/3] take3 sh4: Add IRL(4bit encoded interrupt input) support.

[Blue Swirl]

On 10/28/08, address@hidden <address@hidden> wrote:
> > Isn't it possible to use existing qemu_irq for the signals instead? On
>  > Sparc32, I have used qemu_irq for interrupt lines, reset signals and a
>  > terminal count pulse, one version used it for DMA request.
>
>  I have re-written them using qemu_irq.
>  This use qemu_irq as multi-level signal. I mean LEVEL as in
>   qemu_set_irq(irq, LEVEL) is {0...15} but {0,1}.

If an irq is active at some level, and another irq at some other level
arrives, doesn't the first one get lost? Maybe SH has edge-triggered
irqs and this is OK, I don't know.

Sparc32 has similar 15 level interrupt system with priorities. I've
used a separate qemu_irq for each of these, but perhaps your way could
work if I used a bitmap.