Re: [Qemu-devel] [PATCH 1/3] Fix SDL problems with BGR displays

[Blue Swirl]

On 7/23/08, Blue Swirl <address@hidden> wrote:
> On 7/23/08, Anthony Liguori <address@hidden> wrote:
>  > Andreas Färber wrote:
>  >
>  > > Hi,
>  > >
>  > > Am 22.07.2008 um 22:51 schrieb Anthony Liguori:
>  > >
>  > >
>  > > > From: Avi Kivity <address@hidden>
>  > > >
>  > > > kvm: qemu: revert qemu's sdl.c rev 1.40
>  > > >
>  > > > this fixes problems with bgr displays.
>  > > >
>  > >
>  > > What problems exactly are you fixing? Could other backends such as Cocoa
>  > be affected, too?
>  > >
>  >
>  >  The original commit in question is 2974.  I don't have the ability to test
>  > Cocoa but we received a bug report about a BGR display regression shortly
>  > after this commit.  Reverting this particular part of the commit made the
>  > problem go away.  See
>  > http://thread.gmane.org/gmane.comp.emulators.kvm.devel/7773
>  >
>  >  Perhaps Blue Swirl can comment if reverting this part of the patch
>  > regresses some of the test cases he was working with when he committed the
>  > original patch?
>
>
> I can't reproduce the problem anymore, even reverting the patch
>  changes nothing at depth 16. There seems to be other bugs involved,
>  for example at depth 15 everything looks cosmic. Maybe VGA memory
>  accesses assume some host endianness which are wrong on big endian
>  host.
>

This patch gets 15 bit display working for me. SDL BitsPerPixel never
indicates any values other than multiples of 8, so we need to check
for strange depths. Any comments?

sdl_fix_15bits.diff
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