Hi Alexey, Daniel, On 05-04-2018 10:32, Daniel Vetter wrote: > On Thu, Apr 5, 2018 at 9:16 AM, Alexey Brodkin > <Alexey.Brodkin at synopsys.com> wrote: >> Hi Daniel, >> >> On Thu, 2018-04-05 at 08:18 +0200, Daniel Vetter wrote: >>> On Wed, Apr 4, 2018 at 10:06 PM, Alexey Brodkin >>> <Alexey.Brodkin at synopsys.com> wrote: >>>> Hello, >>>> >>>> We're trying to use DisplayLink USB2-to-HDMI adapter to render GPU-accelerated graphics. >>>> Hardware setup is as simple as a devboard + DisplayLink adapter. >>>> Devboards we use for this experiment are: >>>> * Wandboard Quad (based on IMX6 SoC with Vivante GPU) or >>>> * HSDK (based on Synopsys ARC HS38 SoC with Vivante GPU as well) >>>> >>>> I'm sure any other board with DRM supported GPU will work, those we just used >>>> as the very recent Linux kernels could be easily run on them both. >>>> >>>> Basically the problem is UDL needs to be explicitly notified about new data >>>> to be rendered on the screen compared to typical bit-streamers that infinitely >>>> scan a dedicated buffer in memory. >>>> >>>> In case of UDL there're just 2 ways for this notification: >>>> 1) DRM_IOCTL_MODE_PAGE_FLIP that calls drm_crtc_funcs->page_flip() >>>> 2) DRM_IOCTL_MODE_DIRTYFB that calls drm_framebuffer_funcs->dirty() >>>> >>>> But neither of IOCTLs happen when we run Xserver with xf86-video-armada driver >>>> (see https://urldefense.proofpoint.com/v2/url?u=http-3A__git.arm.linux.org.uk_cgit_xf86-2Dvideo-2Darmada.git_log_-3Fh-3Dunstable-2Ddevel&d=DwIBaQ&; >>>> c=DPL6_X_6JkXFx7AXWqB0tg&r=lqdeeSSEes0GFDDl656eViXO7breS55ytWkhpk5R81I&m=oEAlP64L9vkuUs_k3kGwwwlN1WJbDMJbCo0uDhwKwwk&s=3ZHj- >>>> 6JXZBLSTWg_4KMnL0VNi7z8c0RxHzj2U5ywVIw&e=). >>>> >>>> Is it something missing in Xserver or in UDL driver? >>> Use the -modesetting driverr for UDL, that one works correctly. >> If you're talking about "modesetting" driver of Xserver [1] then indeed >> picture is displayed on the screen. But there I guess won't be any 3D acceleration. >> >> At least that's what was suggested to me earlier here [2] by Lucas: >> ---------------------------->8--------------------------- >> For 3D acceleration to work under X you need the etnaviv specific DDX >> driver, which can be found here: >> >> https://urldefense.proofpoint.com/v2/url?u=http-3A__git.arm.linux.org.uk_cgit_xf86-2Dvideo-2Darmada.git_log_-3Fh-3Dunstable-2Ddevel&d=DwIGaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=yaVFU4TjGY0gVF8El1uKcisy6TPsyCl9uN7Wsis-qhY&m=NxAlhKaLZI6JlMs1pUBPHr79zFQ8ytECx0wtkVRrkeQ&s=9XSI0qYPrADUy1eUuKDexVOT98l9APph-ArYowGWwow&e= > You definitely want to use -modesetting for UDL. And I thought with > glamour and the corresponding mesa work you should also get > accelaration. Insisting that you must use a driver-specific ddx is > broken, the world doesn't work like that anymore. I think what Alexey wants to do is not supported by -modesetting driver. He wants to offload rendering to a Vivante GPU and then display the result in *another* output ... For this I think full PRIME support is needed, right? I see -modesetting has drmPrimeFDToHandle but no drmPrimeHandleToFD support. In other words -modesetting can not export buffers to another -modesetting driver, it can only import them (?) Thanks and Best Regards, Jose Miguel Abreu > > Lucas, can you pls clarify? Also, why does -armada bind against all > kms drivers, that's probaly too much. > -Daniel > >> ---------------------------->8--------------------------- >> >> [1] https://urldefense.proofpoint.com/v2/url?u=https-3A__cgit.freedesktop.org_xorg_xserver_tree_hw_xfree86_drivers_modesetting&d=DwIGaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=yaVFU4TjGY0gVF8El1uKcisy6TPsyCl9uN7Wsis-qhY&m=NxAlhKaLZI6JlMs1pUBPHr79zFQ8ytECx0wtkVRrkeQ&s=yvnVItPaOgvVT8aJFwTO5XXLCCmlSiD89JwhcGeo7MI&e= >> [2] https://urldefense.proofpoint.com/v2/url?u=http-3A__lists.infradead.org_pipermail_linux-2Dsnps-2Darc_2017-2DNovember_003031.html&d=DwIGaQ&c=DPL6_X_6JkXFx7AXWqB0tg&r=yaVFU4TjGY0gVF8El1uKcisy6TPsyCl9uN7Wsis-qhY&m=NxAlhKaLZI6JlMs1pUBPHr79zFQ8ytECx0wtkVRrkeQ&s=8gdiQaxAN7AT_2vwaIpXpXfVPSPKPM275rlmcQZKu28&e= >> >> -Alexey > >
