--- Ville Syrjälä <[EMAIL PROTECTED]> wrote: > On Thu, Oct 07, 2004 at 02:02:38PM +0100, Alan Cox wrote: > > > Note that there's some code in there already which uses the blitter > to copy > > > from framebuffer to agp memory, though it tries to implement the > entire > > > readpixels() operation rather than being a useful low-level > operation. > > > > AGP memory is hostside uncached (CPU limitations on x86 for one) which > > means it is better (swap PCI for DDR ram bus latencies is good) but > > still benefits from the treatment. > > Why can't we make AGP memory cached? Wouldn't it be enought to flush the > > caches at some critical points? > > I was playing around with DirectFB and AGP some years ago and enabling > write-back caching didn't seem to have any side effects. Without caching > > AGP is almost as bad as video memory for sw fallbacks. > I don't get it... We would have to flush the cache after the AGP transfer any way, right?
If this truely can't be cached then woulden't the AGP transfer slow us down even more? So unless we get vastly improved performance, the end result is more painfull to use the AGP transfer. > -- > Ville Syrjälä > [EMAIL PROTECTED] > http://www.sci.fi/~syrjala/ > > > ------------------------------------------------------- > This SF.net email is sponsored by: IT Product Guide on ITManagersJournal > Use IT products in your business? Tell us what you think of them. Give > us > Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out > more > http://productguide.itmanagersjournal.com/guidepromo.tmpl > -- > _______________________________________________ > Dri-devel mailing list > [EMAIL PROTECTED] > https://lists.sourceforge.net/lists/listinfo/dri-devel > _______________________________ Do you Yahoo!? Declare Yourself - Register online to vote today! http://vote.yahoo.com ------------------------------------------------------- This SF.net email is sponsored by: IT Product Guide on ITManagersJournal Use IT products in your business? Tell us what you think of them. Give us Your Opinions, Get Free ThinkGeek Gift Certificates! Click to find out more http://productguide.itmanagersjournal.com/guidepromo.tmpl -- _______________________________________________ Dri-devel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/dri-devel
