Re: [Qemu-devel] [RFC PATCH] ati-vga: Implement dummy VBlank IRQ

[Gerd Hoffmann]

  Hi,

> > > +static void ati_vga_update_irq(ATIVGAState *s)
> > > +{
> > > +    pci_set_irq(&s->dev, s->regs.gen_int_status & 1);
> > 
> > This should be "s->regs.gen_int_status & s->regs.gen_int_cntl" I guess?
> 
> Probably, but we only try to emulate VBlank yet so to avoid any problems due
> to raising irq for unknown bits I restricted it for that now.

Well, qemu doesn't set unknown status bits, only vblank.  The guest
can't set them either due to status register having write-one-to-clear
semantics.  So, that should not happen.  If you want an extra check to
catch programming errors I'd suggest to add an assert() for that.

> > > +        s->regs.gen_int_status &= ~data;
> > 
> > ati_vga_update_irq() needed here too.
> 
> Thanks. Indeed I forgot this. With that it works a bit better, mouse now can
> be moved but only vertically... No idea why, I'll have to check,

Still progress.  One step at a time ;)

cheers,
  Gerd