Hey, I've been playing a bit with nouveau on aarch64, and I noticed ttm translates ttm_uncached into pgprot_noncached which uses MT_DEVICE_nGnRnE. This is of course a device mapping which isn't appropriate for memory.
For main memory we should be using pgprot_dmacoherent which translates to MT_NORMAL_NC, pgprot_writecombine also translates to MT_NORMAL_NC. Now I'm not sure anything gets this wrong right now, (except maybe nouveau), but I'm wondering would adding a ttm_uncached_ram caching type and rename ttm_uncached to ttm_uncached_device, if that would be a good idea? Has anyone else come across this problem with TTM on aarch64? or understand if I'm missing something. Dave.
