Re: [Mesa3d-dev] radeon r200 TCL in xorg-video-ati 6.10

[Roland S. <sr...@vm...>]

On 29.04.2009 16:12, martin krastev wrote:
> Thank you, Roland, that explains it all. When i said the code was
> running that much faster on almost the same configuration - that other
> config is AGPx4, with a native OSX driver edge for the rv280 (it's a
> mac). And yes, the vertex arrays are large. So in one case we have
> larger vertex arrays perpetually traversing a (66MHz) PCI bus, in the
> other - proper VBOs over an AGPx4 bus - that could easilly account for
> an order of magnitude, and then some, for this task. And this given
> that fillrate alone is better on the PCI ATI (later model, faster
> clocks, wider memory bus, etc).
> 
> let's say i decided to hack a rudimentarty allocate-only/no-deallocate
> memory manager for STATIC_DRAW VBOs into the edge, not for
> upstreaming, just for my purposes here, where would you advise me to
> start looking at? Also, should i be able to do with just the present
> sources, no futher NDA'd specs required?

I think you wouldn't need any NDA's specs. If you want to make the index
buffer also reusable, you need to use the INDX_BUFFER packet which isn't
used in the r200 driver. However, r300 works just the same there (and
does use it).
I dunno where to start, though. The r300 driver once upon a time
actually used (now defunct and ifdefed out) USER_BUFFERS code to
implement vbo without real memory management. Maybe that's a start, r200
and r300 don't really differ there. Otherwise, it would probably be
easier to use the radeon-rewrite branch along with the appropriate drm
bits and just implement it for real...


Roland