topic Re: Image flickering problem after running the application program in i.MX Processors

Image flickering problem after running the application program

ramanjineyuluth — Tue, 27 Jun 2017 06:35:09 GMT

Hi,

I am currently working on image flickering problem. I am using "galcore" kernel module and running the application of triangle shape. When i have run the application the image starts flickering.

I could not understand the problem in GPU driver and video driver.

In application we can use sleep() function to avoid the flickering issue, but if we want to run multiple applications we could not use the sleep() function.

Issue: I suspect the issue with GPU usage is increase then video driver starts to flickering but in GPU driver where exactly i have to find the GPU usage is increasing or not.

Could you please help on this to change the GPU driver to avoid the flicking issue.

Thanks in advance.

Thanks & Regards,

Ramanjineyulu.

Re: Image flickering problem after running the application program

igorpadykov — Tue, 27 Jun 2017 10:43:34 GMT

Hi Ramanjineyulu.

if sleep() helps, seems application consumes too much memory/buses bandwidth

so no left for gpu. One can run profile tool below to estimate that

About MMDC Profiling Tool for i.MX6

It is not possible change the GPU driver to avoid that, it is nesessary to allocate

resources between applications to allow gpu to function properly.

Best regards
igor
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Re: Image flickering problem after running the application program

ramanjineyuluth — Tue, 27 Jun 2017 12:38:46 GMT

Hi Igor,

Thanks a lot for your feedback.

I could not use sleep() function in application because what ever you said above is correct.

Please let me know, there is no changes in GPU driver side okay, what about DCU(2D-ACE) video drivers.

In Linux source code the driver files are "/drivers/video" folder.

Do you have any application code which flicking problem not exists. It's very helpful for us.

Could you please send working code it is helpful to avoid this issue, if not please send some links to understand in detail about the GPU driver and the application code.

Thanks & Regards,

Ramanjineyulu.

Re: Image flickering problem after running the application program

igorpadykov — Tue, 27 Jun 2017 23:21:20 GMT

Hi Ramanjineyulu

if this is Vybrid, please note that nxp does not provide or support linux for it.

It is provided by timesys. In general one can try to increase QoS for gpu and memory

using AN4947 Understanding Vybrid Architecture

http://www.nxp.com/docs/en/application-note/AN4947.pdf

Best regards
igor

Re: Image flickering problem after running the application program

ramanjineyuluth — Wed, 28 Jun 2017 10:25:41 GMT

Hi Igor,

Thanks for your reply.

I am not using Vybrid controller. I am using s32v234 processor.

Could you please help on this processor DCU drivers and application.

GPU driver(galcore.ko) inserted successfuly when running the application it starts flickering.

There are some warnings it displays, Please see the below

insmod galcore.ko
[ 32.027606] Warning: No contiguous memory is reserverd for gpu.!
[ 32.027606]
[ 32.034871] Warning: Will use default value(134217728) for the reserved memory!
[ 32.034871]
[ 32.043732] Galcore version 5.0.11.41671
[ 32.059745] galcore 40020000.gpu: swiotlb buffer is full (sz: 134217728 bytes)
[ 32.067126] galcore 40020000.gpu: swiotlb buffer is full (sz: 130023424 bytes)
[ 32.074475] galcore 40020000.gpu: swiotlb buffer is full (sz: 125829120 bytes)
[ 32.081832] galcore 40020000.gpu: swiotlb buffer is full (sz: 121634816 bytes)
[ 32.089142] galcore 40020000.gpu: swiotlb buffer is full (sz: 117440512 bytes)
[ 32.096479] galcore 40020000.gpu: swiotlb buffer is full (sz: 113246208 bytes)
[ 32.103836] galcore 40020000.gpu: swiotlb buffer is full (sz: 109051904 bytes)
[ 32.111172] galcore 40020000.gpu: swiotlb buffer is full (sz: 104857600 bytes)
[ 32.118480] galcore 40020000.gpu: swiotlb buffer is full (sz: 100663296 bytes)
[ 32.125834] galcore 40020000.gpu: swiotlb buffer is full (sz: 96468992 bytes)

Could you please tell me how to resolve it, may this swiotlb buffer is full that's why flickering is happen or any solution.

Thanks & Regards,

Ramanjineyulu.

Re: Image flickering problem after running the application program

igorpadykov — Wed, 28 Jun 2017 11:48:32 GMT

Hi Ramanjineyulu

I am not s32v234 expert and there was no mention in that

thread about it. Please create new thread and write topic name

name as s32v234 processor so expert for that processor could answer you.

I am sorry for the inconvenience.

Best regards
igor

Re: Image flickering problem after running the application program

ramanjineyuluth — Wed, 28 Jun 2017 14:09:45 GMT

Hi Igor,

Thanks for your reply.

Last one question, I would like to know in GPU driver, in which file the GPU usage is increasing.

Could you please help where i have to look for this in GPU driver.

Please help on this, I could not ask any more.

It is very helpful for me.

Thanks & Regards,

Ramanjineyulu.

Re: Image flickering problem after running the application program

igorpadykov — Wed, 28 Jun 2017 14:55:00 GMT

Hi Ramanjineyulu

there is special s32 community: community.nxp.com/community/s32/s32k

S32K

please post there

Best regards
igor