On Mon, 2020-09-14 at 11:17 -0300, Jason Gunthorpe wrote: > On Fri, Sep 11, 2020 at 09:42:25PM +0000, Clint Sbisa wrote: > > > There's no DMA involved with this BAR-- the driver writes a portion > > of the > > packet contents in addition to the descriptors, which generally > > increases the > > number of TLPs if write-combine isn't used. Furthermore, this BAR > > is only used > > for writes and never for reads. > > You use DPDK without DMA? How does receive work? > > > As Jason noted in the other reply to this email, the Linux ENA > > driver makes use > > of WC by using devm_ioremap_wc(). > > As Ben noted we don't have kernel accessors to make this portable or > safe :( Well.. to be frank it does work "well enough" for simple cases like frame buffers :-) Cheers Ben.
