On Tue, Sep 15, 2020 at 08:00:27AM +1000, Benjamin Herrenschmidt wrote: > On Tue, 2020-09-15 at 07:42 +1000, Benjamin Herrenschmidt wrote: > > > > > which is back to my original question, how do you do DMA using > > > /sys/xx/resources? Why not use VFIO like everything else? > > > > Note: All this doesnt' change the fact that sys/xx/resources_wc > > exists > > for other archs and I see no reasons so far not to have it on ARM... > > Also... it looks like VFIO also doesn't provide a way to do WC yet > unfortunately :-( > > There was a discussion 2 or 3 years ago while I was at IBM about ways > to add that functionality, but it doesn't seem to have resulted in > anything. And to complete answering the question, the ENA PMD in DPDK also supports vfio, which-- as Ben pointed out-- doesn't support WC either. Clint
