On 20 April 2017 at 07:10, Anuradha Ranasinghe <anuradha@xxxxxxxxxxxxxx> wrote: > Dear All, > > This issue is associated to the Linux Mainline Kernel 4.1.15.2 (branch2) > tw686x upstream driver and IMX6Q platform. > > We have an analog camera capture board (a custom one) based around tw6865. > We are interfacing it with Nitrogen6_Max board (IMX6Q) . We use the > aforementioned kernel with the boundary devices latest patches to the tw686x > driver (having 3 DMA buffers) and system running on Ubuntu 16 Xenial Mate > version. > https://github.com/boundarydevices/linux-imx6/commits/7fcd22da6d731b36e5ab856551c41301fca9881f > > The driver initialization, device and composite signal detection work well > as intended. But when the streaming started, frame rate becomes lower and > after few frames, the whole system freezes. To get the camera to work to > this level, we had to do : > What dma-mode are you using? Have you tried other dma-modes? How many frames do you manage to obtain? I believe you should debug this further and provide more information. > 1. Disable PCI interrupts from the kernel (from menuconfig and pci=nomsi > kernel command) (CCing PCI people) Lucas, Richard: any idea about why is this parameter needed? > 2. Set Coherent_Pool to 128M in boot args to get the memory allocation for > driver. Without this driver does not enumerate. > Hm.. interesting. > I can confirm that there is no issue in our hardware. I strictly followed > the free scale data sheet recommendations. So I have few questions needing > your answers : > >> Have you guys tried this driver for tw6865 or a related chip on same root >> fs ? If not can you kindly mention the operating condition you had ? FWIW, I have tested tw6869 on x86_64. It works well here, but only using dma-mode=memcpy, as documented here: http://lxr.free-electrons.com/source/drivers/media/pci/tw686x/tw686x-core.c#L19 >> Is attached patch required for higher kernel versions (4.1.15) to support >> DMA accessing ? I have no idea about that patch. The patch has nothing to do with tw686x, but it's i.MX6 platform-specific, you should ask the author. >> Is there any additional settings (cma allocation, memory mapping) required >> for this newer kernel ? That depends on your platform and usage. >> I use the pipeline : > gst-launch-1.0 v4l2src device=/dev/video0 ! video/x-raw,width=720,height=480 > ! autovideosink > for an unknown reason, imxv4l2videosrc does not work at all for this pcie > camera. > You need to ask imxv4l2videosrc's authors. -- Ezequiel García, VanguardiaSur www.vanguardiasur.com.ar
