On Fri, Jan 31, 2020 at 12:55:45PM +0200, Jani Nikula wrote: > On Fri, 31 Jan 2020, "Bharadiya,Pankaj" <pankaj.laxminarayan.bharadiya@xxxxxxxxx> wrote: > > I am exploring the way of implementing the pipe writeback feature in i915 and > > would like to get early feedback on design. > > > > We have a Wireless display(WD) transcoder which can be used for capturing > > display pipe output to memory. It is generally intended for wireless display, > > but can be used for other functions such as in validation automation where crc > > based comparison is not feasible. > > I think you should probably explore the use case and driver/igt impact > further before embarking on the implementation. > > - How much do you need to modify existing code in kernel and igt to make > use of writeback connectors? > > - What kind of test coverage do you get? Pipe CRC is used in connection > with the physical encoders. In contrast, you won't have that with WD > transcoders. (Design wise I think this may mean you'll also need > "writeback encoders", instead of trying to plug it into existing > encoders.) So you'll only test the pipe side of things, which roughly > corresponds to pipe CRC coverage I guess. I guess it could speed up > that part of testing because you can then skip the physical > connectors, but you do have to test them also. So it's not a panacea. The main benefit I'm looking forward to is for reverse engineering. As in answwering the age old question: "let me see wtf the hw is actually doing to my pixels?". I want this! -- Ville Syrjälä Intel --------------------------------------------------------------------- Intel Finland Oy Registered Address: PL 281, 00181 Helsinki Business Identity Code: 0357606 - 4 Domiciled in Helsinki This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
