Re: Hi again

[Sylwester Nawrocki <sylvester.nawrocki@gmail.com>]

On 02/07/2013 12:53 AM, Sylwester Nawrocki wrote:
> root@mini2440:~ echo 100 > /sys/module/videobuf2_core/parameters/debug
>
> root@mini2440:~ gst-launch -v v4l2src device=/dev/video0 queue-size=2
> ! video/x-raw-yuv,format='(fourcc)'YV12 ! ffmpegcolorspace ! fbdevsink
>
> root@mini2440:~ dmesg -c
> [ 1907.110000] s3c-camif s3c2440-camif: dma_alloc_coherent of size
> 12582912 failed
> [ 1907.115000] vb2: Failed allocating memory for buffer 1
>
> The error is ignored here, it should all fail at this point.
>
> [ 1907.120000] vb2: Buffer 0, plane 0 offset 0x00000000
> [ 1907.125000] vb2: Allocated 1 buffers, 1 plane(s) each
> [ 1907.220000] vb2: Buffer 0, plane 0 successfully mapped
> [ 1907.225000] vb2: qbuf of buffer 0 succeeded
> [ 1907.230000] vb2: Streamon successful

I've found there is a bug in the driver. It happens that only one buffer
out of two gets allocated and the minimum required for the driver to start
streaming is 2. I've pushed a patch fixing this bug [1] to the 3.7 based
testing/s3c-camif branch. I'll post it to LMML in a minute.

It won't really solve your problem, but at least there is now clear
indication what's wrong, and the application should not get stuck. Please
check you CMA memory region size. I suspect that you use the default 16 MB
and it allows you to allocate only one buffer. 16 MB might still be
sufficient for 1280x1024 - OV9650's maximum resolution. Anyway, it might
be worth to check what CONFIG_CMA_SIZE_MBYTES is set to.
(Device drivers -> Generic Driver Options -> Contiguous Memory Allocator)

>> [23:07]<KaKaRoTo> which is also why it freezes (doesn't output
>> buffers) instead of giving an error when you try to set that
>> resolution

Thanks,
Sylwester