topic Re: [iMX6q]Capture BT.656-4 NTSC to preview, it has a screen scroll problem. in i.MX Processors

[iMX6q]Capture BT.656-4 NTSC to preview, it has a screen scroll problem.

xiangkunkong — Thu, 15 Jul 2021 08:14:54 GMT

Hi, all

We have tried two solutions at below, but both are not worked.(kernel version 3.10)

1. set active top(mxc_v4l2_capture.c) value 3, or 4, or 13

Actully we tried 1~255...

2. Refer [5 Common issue] of i.MX6_IPU_TVIN_Application_Notes.pdf, and also tried the patch of [5.1.1 Detect NFB4EOF Error or TVIN Signal Lock Lost].

Waring log:

imx-ipuv3 2400000.ipu: IPU Warning - IPU_INT_STAT_5 = 0x00000001 (NFB4EOF error)
imx-ipuv3 2400000.ipu: IPU Warning - IPU_INT_STAT_10 = 0x00080000

We are using tc90105fg video decoder, and known its output blanking video is unragular.

----- pre line data + EAV + blanking samples + SAV + next line data ----

the blanking samples are unragular, it's a not fixed value.

Let me know if you have any advice.

Thanks,

kong

Re: [iMX6q]Capture BT.656-4 NTSC to preview, it has a screen scroll problem.

igorpadykov — Fri, 16 Jul 2021 00:31:59 GMT

Hi Kong

IPU_INT_STAT_10 =0x00080000" points to data starvation when data that should be sent to display is not available in IPUs internal FIFO. Most probable cause for this issue is huge load on the DDR memory bus. One can try to set IPU prioirty higher using sect.36.4.7 GPR (IOMUXC_GPR6)

i.MX 6Dual/6Quad Applications Processor Reference Manual

Best regards
igor

Re: [iMX6q]Capture BT.656-4 NTSC to preview, it has a screen scroll problem.

xiangkunkong — Mon, 26 Jul 2021 00:10:30 GMT

Hi igorpadykov,

Thanks for your reply.

I tried it(0x7F007F -> 0xFF00FF), but the issue is not be fixed.

Re: [iMX6q]Capture BT.656-4 NTSC to preview, it has a screen scroll problem.

xiangkunkong — Wed, 11 Aug 2021 00:33:30 GMT

I'm trying add vsync/hsync signal on my sabre for testing, i will back and share my result.