On Wed, 2005-06-29 at 13:36 -0400, Jon Smirl wrote: > On 6/29/05, Keith Whitwell <[EMAIL PROTECTED]> wrote: > > Jon Smirl wrote: > > > In i810/server/i810_dri.c there is a call to agp alloc without the > > > type set to zero: > > > drmAgpAlloc(ctx->drmFD, 4096 * 1024, 1, NULL, &dcacheHandle); > > > > > > A type of one translates into U16_APER_SIZE which doesn't match the > > > request size of 4MB. > > > > > > Is this a bug or do I not understand the type parameter on agp alloc? > > > This is the only place where a type other than zero is used. > > > > > > > The i810 had an optional bank of dedicated video ram, the "dcache", > > which was useful for certain tasks despite having lower bandwidth than > > regular shared/system ram. This memory required special handling - I > > would say the type parameter would have been added for this case in > > particular. > > > > Note that this is not the same as the i810's "stolen" ram which is > > allocated off the top of regular memory at boot time by the bios. > > If I am reading the code right the type ends up straight in the > kernel's agp_allocate_memory(pages, type); Then looking at the kernel > code the type goes into the chip agp driver and then comes back out > later. I can't find any documentation on what 'type' does. > > I don't have any reason to think it's not working, it was just odd > that it was the only non-zero use in the system.
Type 0 is normal. Type of 1 specifies that it's dcache. Type of 2 specifies cursor memory. The AGP driver respects the type and allocates from the appropriate place. -- Eric Anholt [EMAIL PROTECTED] http://people.freebsd.org/~anholt/ [EMAIL PROTECTED] ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click -- _______________________________________________ Dri-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dri-devel
