DRM/V4L2 buffer sharing (was: Re: Patches submitted via linux-media ML that are at patchwork.linuxtv.org)
Hi Laurent, On 08/15/2012 11:09 PM, Laurent Pinchart wrote: > On Wednesday 15 August 2012 18:13:19 Sylwester Nawrocki wrote: >> On 08/15/2012 12:06 AM, Laurent Pinchart wrote: >>> On Tuesday 14 August 2012 18:37:23 Sylwester Nawrocki wrote: On 08/14/2012 03:04 PM, Mauro Carvalho Chehab wrote: > This one requires more testing: > > May,15 2012: [GIT,PULL,FOR,3.5] DMABUF importer feature in V4L2 API >http://patchwork.linuxtv.org/patch/11268 Sylwester Nawrocki > Hmm, this is not valid any more. Tomasz just posted a new patch series that adds DMABUF importer and exporter feature altogether. [PATCHv8 00/26] Integration of videobuf2 with DMABUF I guess we need someone else to submit test patches for other H/W than just Samsung SoCs. I'm not sure if we've got enough resources to port this to other hardware. We have been using these features internally for some time already. It's been 2 kernel releases and I can see only Ack tags from Laurent on Tomasz's patch series, hence it seems there is no wide interest in DMABUF support in V4L2 and this patch series is probably going to stay in a fridge for another few kernel releases. >>> >>> What would be required to push it to v3.7 ? >> >> Mauro requested more test coverage on that, which is understood since this >> is a fairly important API enhancement and the V4L2 video overlay API >> replacement. >> >> We need DMABUF support added at some webcam driver and a DRM driver with >> prime support (or some V4L2 output driver), I guess it would be best to >> have that in a PC environment. It looks like i915/radeon/nouveau drivers >> already have prime support. > > uvcvideo has recently been moved to videobuf2, using vb2_vmalloc. I can easily > test that, except that I have no idea how to export buffers on the i915 side > when X is running. Have you looked into that ? All right. Yes, I'm also not sure yet how to do it. I tried it on a laptop with i915 driver, but in the running system drmModeGetResources() just fails with EPERM. I've CCed dri-devel, so hopefully someone can shed some light on this. >> The DRM driver could be an exporter of buffers that would be passed to the >> webcam driver. >> >> And except the kernel patches we would need a test application, similar >> to that one: >> http://git.infradead.org/users/kmpark/public-apps/blob/a7e755629a74a7ac13788 >> 2032a0f7b2480fa1490:/v4l2-drm-example/dmabuf-sharing.c >> >> I haven't been closely following the DMABUF APIs development, I think >> Tomasz could provide more details on that. >> >> It's likely I'll get around and prepare a test case as outlined above in >> coming days. Anyway, it would be appreciated if someone else could give this >> patch series a try. > > I've previously tested the patches on Renesas hardware, exporting buffers on > the FBDEV side and importing them on the V4L2 side. We thus have test results > for two different platforms, albeit all ARM-based. I guess ARM is where those APIs will be used mostly, still it would be helpful to have easier reproducible test environment. -- Thanks, Sylwester
DRM/V4L2 buffer sharing (was: Re: Patches submitted via linux-media ML that are at patchwork.linuxtv.org)
Hi Laurent, On 08/15/2012 11:09 PM, Laurent Pinchart wrote: On Wednesday 15 August 2012 18:13:19 Sylwester Nawrocki wrote: On 08/15/2012 12:06 AM, Laurent Pinchart wrote: On Tuesday 14 August 2012 18:37:23 Sylwester Nawrocki wrote: On 08/14/2012 03:04 PM, Mauro Carvalho Chehab wrote: This one requires more testing: May,15 2012: [GIT,PULL,FOR,3.5] DMABUF importer feature in V4L2 API http://patchwork.linuxtv.org/patch/11268 Sylwester Nawrocki s.nawro...@samsung.com Hmm, this is not valid any more. Tomasz just posted a new patch series that adds DMABUF importer and exporter feature altogether. [PATCHv8 00/26] Integration of videobuf2 with DMABUF I guess we need someone else to submit test patches for other H/W than just Samsung SoCs. I'm not sure if we've got enough resources to port this to other hardware. We have been using these features internally for some time already. It's been 2 kernel releases and I can see only Ack tags from Laurent on Tomasz's patch series, hence it seems there is no wide interest in DMABUF support in V4L2 and this patch series is probably going to stay in a fridge for another few kernel releases. What would be required to push it to v3.7 ? Mauro requested more test coverage on that, which is understood since this is a fairly important API enhancement and the V4L2 video overlay API replacement. We need DMABUF support added at some webcam driver and a DRM driver with prime support (or some V4L2 output driver), I guess it would be best to have that in a PC environment. It looks like i915/radeon/nouveau drivers already have prime support. uvcvideo has recently been moved to videobuf2, using vb2_vmalloc. I can easily test that, except that I have no idea how to export buffers on the i915 side when X is running. Have you looked into that ? All right. Yes, I'm also not sure yet how to do it. I tried it on a laptop with i915 driver, but in the running system drmModeGetResources() just fails with EPERM. I've CCed dri-devel, so hopefully someone can shed some light on this. The DRM driver could be an exporter of buffers that would be passed to the webcam driver. And except the kernel patches we would need a test application, similar to that one: http://git.infradead.org/users/kmpark/public-apps/blob/a7e755629a74a7ac13788 2032a0f7b2480fa1490:/v4l2-drm-example/dmabuf-sharing.c I haven't been closely following the DMABUF APIs development, I think Tomasz could provide more details on that. It's likely I'll get around and prepare a test case as outlined above in coming days. Anyway, it would be appreciated if someone else could give this patch series a try. I've previously tested the patches on Renesas hardware, exporting buffers on the FBDEV side and importing them on the V4L2 side. We thus have test results for two different platforms, albeit all ARM-based. I guess ARM is where those APIs will be used mostly, still it would be helpful to have easier reproducible test environment. -- Thanks, Sylwester ___ dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel
