Tom Sylla wrote: > http://openbios.org/viewvc/cpu/x86/pc/olpc/lxmsrs.fth?view=markup&revision=739&root=OpenFirmware > has: > msr: 0000.1810 fdfff000.fd000111. \ Video (write through), fbsize > > which is setting the framebuffer as write-combining. (the "write > through" comment is incorrect)
This takes care of the physical mapping, but how would userspace be able to mmap the framebuffer into virtual memory without additional MMU programming? I was under the impression that we also need to cover the whole region with small 4KB MMU pages. This degrades performance somewhat due to TLB misses when the CPU accesses the framebuffer. But I must confess I have limited understanding of the Geode architecture, so I may be overlooking something. -- \___/ |___| Bernardo Innocenti - http://www.codewiz.org/ \___\ One Laptop Per Child - http://www.laptop.org/ _______________________________________________ Devel mailing list Devel@lists.laptop.org http://lists.laptop.org/listinfo/devel
