On Mon, 14 Mar 2005 10:48:19 +1100, Benjamin Herrenschmidt <[EMAIL PROTECTED]> wrote: > > > > That shouldn't matter the page brought in would be for a speculative > > > read and never accessed. It should just fall out of the cache and not > > > be written back. There is only one cachable mapping. In this model > > > writes are always followed by a flush before telling the GPU to access > > > the memory that has just been written. > > > > What about this scenario? > > > > Speculative read -> AGP master writes new data -> CPU has invalid data in > > cache :( >
You need to reverse the cache flush process if you are going to read data written by the GPU. 1) Make sure GPU is finished writing 2) flush your cache 3) read AGP memory like normal RAM. -- Jon Smirl [EMAIL PROTECTED] ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://ads.osdn.com/?ad_id=6595&alloc_id=14396&op=click -- _______________________________________________ Dri-devel mailing list Dri-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dri-devel
