Re: [RFC PATCH 7/7] drm/pci: Defer initialization of secondarygraphics devices until switcheroo is ready

From: Seth Forshee
Date: Mon Aug 20 2012 - 11:56:33 EST


On Mon, Aug 20, 2012 at 04:36:40PM +0100, Matthew Garrett wrote:
> On Mon, Aug 20, 2012 at 10:31:04AM -0500, Seth Forshee wrote:
> > + /*
> > + * For secondary graphics devices shouldn't be initialized
> > + * until the handler and primary graphics device have been
> > + * registered with vga_switcheroo.
> > + *
> > + * FIXME: Is vga_default_device() reliable enough for this
> > + * purpose?
> > + *
> > + * FIXME: If vga_switcheroo is disabled secondary devices
> > + * never gets initialized. Is this okay? Maybe it is, since
> > + * we can't switch to the secondary GPU anyway.
> > + */
>
> Won't this break the multiple cards with independent outputs case?

Yes, if they don't have a switcheroo handler. I only have experience
with one such machine, which had optimus graphics. My recollection is
that it did have a switcheroo handler, which was only capable of
controlling power to the discrete card.

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