Hey, Op 04-06-13 20:38, Ilia Mirkin schreef: > On Mon, Jun 3, 2013 at 5:02 AM, Ilia Mirkin <imirkin@xxxxxxxxxxxx> wrote: >> These chipsets include the VP2 engine which is composed of a bitstream >> processor (BSP) that decodes H.264 and a video processor (VP) which can >> do iDCT/mo-comp/etc for MPEG1/2, H.264, and VC-1. Both of these are >> driven by separate xtensa chips embedded in the hardware. This patch >> provides the mechanism to load the kernel for the xtensa chips and >> provide the necessary interactions to do the rest of the work. >> >> Signed-off-by: Ilia Mirkin <imirkin@xxxxxxxxxxxx> >> --- >> >> This patch applies on top of nouveau/master (16a41bcc8). >> >> This seems to work for me. There was one boot where my userspace >> component didn't work right, but it could just as well be a bug >> there. Subsequent attempts seem to work fine. Note that I'm not >> particularly familiar with any of this stuff, so if something looks >> odd, I probably didn't know any better. I did try to faithfully >> reproduce whatever the blob did. A few questions/thoughts: >> >> 1. There's a LOT of similarity between BSP and VP setup/etc. Is it >> worth it to create a core/xtensa.c or some such, similar to >> falcon.c? Since it's only in two places, not that much code, and >> there _are_ differences, I decided to keep them separate. >> >> 2. Firmware naming. Maarten suggested to use the falcon naming style, >> which is nv$chipset_fuc$offset. However here, all the chips share >> the same firmware. Also the offset would be 103 vs 00f, and is a >> little arbitrary. (And fuc doesn't apply here... xt? xtensa?) I've >> left it the way I had it: nv84_bsp and nv84_vp. >> >> 3. Firmware load time. I chose to load the fw into memory in the ctor, >> and then copy it in in init, due to some potentially bogus >> suspend/resume concerns. Also e.g. mplayer likes to create/destroy >> decoders at startup a few times. The downside is that ~200KB of >> memory is gone. Let me know if I should change it to do the >> request_firmware in init. >> >> There's obviously a userspace piece to this, which I'm still working >> on. But right now I have it working within certain parameters >> (e.g. 1280x544 videos), and I'm relatively confident it can be >> completed without further kernel-side changes. >> >> There's also a hypothetical concern of "what if we create an open >> firmware with a different user API". Ideally there'd be some way to >> expose what kind of firmware is loaded, but I think that can be left >> for "later". > I also happened to notice that NV98, NVA1+ refer to these nv84 engines > (in drivers/gpu/drm/nouveau/core/engine/device/nv50.c). I assume that > means I should create a new nv98.c version of BSP/VP that resembles > the old versions of nv84.c, and point device/nv50.c at those for nv98 > and nva1+? nv98+ should really have an implementation more like nvc0, and the copy engine is a good example on what conversion is needed to do it. :-) If you fix that up, I'll stop being lazy and fix VP4 for nva3/a5/a8 in mesa. ;) ~Maarten _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
