EXA pixmap alignments.
unichrome at shipmail.org
Mon Oct 3 09:42:06 PDT 2005
Thomas Hellstrom wrote:
> Eric Anholt wrote:
>> On Mon, 2005-09-26 at 09:55 +0200, Thomas Hellstrom wrote:
>>> EXADriverPtr->card.pixmapOffsetAlign = ?
>>> EXADriverPtr->card.pixmapPitchAlign = ?
>>> Is there a chance to have the above parameters defined also for
>>> system to frame-buffer transfers?
>>> For example Unichrome / Unichrome Pro currently requires both to be
>>> 16 for PCI DMA to work, and as briefly discussed on the dri-devel
>>> list, system / frame-buffer bounce buffers to fix alignments may be
>>> very undesirable.
Just to summarize this thread there seems to be an overall consensus
that being able to specify padding and pitch alignments also for system
memory pixmaps would be desirable for most known cards?
The unichromes need common two lower bits for system and framebuffer,
but due to a bug in the chipset, all system memory lines need to start
on a 16 byte boundary.
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