lkml.org 
[lkml]   [2011]   [Sep]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2 10/10] x86, efi: EFI boot stub support
From
Date
On Tue, 2011-09-13 at 14:29 +0100, Matthew Garrett wrote:
> On Mon, Sep 12, 2011 at 03:34:54PM +0100, Matt Fleming wrote:
>
> > + status = efi_call_phys5(sys_table->boottime->locate_handle,
> > + EFI_LOCATE_BY_PROTOCOL, proto,
> > + NULL, &size, gop_handle);
> > + if (status != EFI_SUCCESS)
> > + goto free_handle;
> > +
> > + nr_gops = size / sizeof(void *);
> > + for (i = 0; i < nr_gops; i++) {
> > + void *h = gop_handle[i];
> > +
> > + status = efi_call_phys3(sys_table->boottime->handle_protocol,
> > + h, proto, &gop);
> > + if (status != EFI_SUCCESS)
> > + continue;
> > +
> > + status = efi_call_phys4(gop->query_mode, gop, gop->mode->mode,
> > + &size, &info);
> > + if (status == EFI_SUCCESS)
> > + break;
> > + }
>
> Apple do something funky here, which is to provide a GOP that's not
> backed by real hardware but which muxes writes out to multiple outputs
> in order to handle the multiple display case without screwing up aspect
> ratio. That's fine, except that the stride reported for the fake one is
> just the horizontal width of the logical display. That results in things
> failing badly. The real one also implements PCIIO. My workaround so far
> has been to look for a GOP that handles PCIIO and use it if found, and
> otherwise just fall back to the first GOP.

Ah right, thanks for that. I actually implement that strategy when
searching for a UGA (checking for PCIIO) but without falling back to the
first one if no PCIIO protocol is found. Your proposed scheme seems much
more robust so I'll respin this patch.

--
Matt Fleming, Intel Open Source Technology Center



\
 
 \ /
  Last update: 2011-09-13 16:03    [from the cache]
©2003-2014 Jasper Spaans. Advertise on this site