flickering and splite when using imx8mn with icn6211 mipi to RGB convertor chip

[AccuJie]

Hi,

We have an imx8mn board with an icn6211 chip to convert the MIPI signal to an RGB signal. 

I port the driver which can show the image. However, sometimes the screen is flickering and split. I suspect it is the sync issue or with the DRM driver?

I posted a demo video here https://www.youtube.com/watch?v=00nUH5keII8. The split and flickering are very weird since it seems related to the content of the image. And always have the same width between each splitting. 

Here is the datasheet from our LCD 800*480. 

Here is the parameters I make for the screen:

static const struct drm_display_mode jy20f56_mode = {
	.clock = 33300,
	.hdisplay = 800,
	.hsync_start = 800 + 210,
	.hsync_end = 800 + 210 + 10,
	.htotal = 800 + 210 + 10 + 36,
	.vdisplay = 480,
	.vsync_start = 480 + 22,
	.vsync_end = 480 + 22 + 8,
	.vtotal = 480 + 22 + 8 + 15,
};

static const struct panel_desc jy20f56 = {
	.modes = &y20f56_mode,
	.num_modes = 1,
	.bpc = 8,
	.size = {
		.width = 154,
		.height = 88,
	},
	.bus_format = MEDIA_BUS_FMT_RGB888_1X24,
};

Now I don't have any idea how to debug this kind of issue.

Really appreciate anyone who has any experience or idea.

Thanks,

Jie

[Zhiming_Liu]

Which version of BSP are you using?Can you try the newest BSP?

[AccuJie]

Hi, 

Thanks for your reply.

The BSP version I used is 5.4.24 zeus. Have you ever seen this kind of issue before?

Compiling of the latest BSP is really time consuming. I will have a try this week later.

[Zhiming_Liu]

You can set drm debug mode to see more log when this issue happened.