On Thursday 17 March 2005 18:45, Attila Kinali wrote: > On Thu, 17 Mar 2005 17:27:04 -0500 > > Daniel Phillips <[EMAIL PROTECTED]> wrote: > > Next question: is 32 bits of hardware DMA address enough? That > > handles up to 16 Gigabytes physical memory (assuming 4 byte > > alignment) without having to resort to sickening hacks. Believe > > it or not, 16 GB is commonly thought to be insufficient these days. > > If we limit our selfs to 32bit pci, then it's enough, > but 64 bit is around and is used. Also note that our > cards own memory could be at any place in a 64 bit adress range. > So, i'd say to save us and the driver writers head aches, go > for 64 bit.
Timothy answered that: 40 bits is the number. That is a good choice, and also fairly typical. > > - Provide more bits of DMA address, say 64 > > I would go for that. Actualy, if we assume that we'll > have 4k pages at least, then 52bit would be enough. 64 bit machines normally don't have anywhere close to that amount of physical addressing. > > - Use a cruder base address granularity, say 2**12, which would > > impose texture alignment considerations and basically be a pain > > bad thing[tm] Yep. > > - Fix the problem later, and handle it in a future driver as a > > revision quirk > > Will not be easy. It would be needless busy work at best. Anyway, that problem is solved. Regards, Daniel _______________________________________________ Open-graphics mailing list [email protected] http://lists.duskglow.com/mailman/listinfo/open-graphics List service provided by Duskglow Consulting, LLC (www.duskglow.com)
