i.MX8 display not working after system upgrade

[yi-zhao]

I am new to embedded linux, and I have been struggling with i.MX8MM boards recently. I have a third-party i.MX8 board that works fine on the default built-in system (which should be zeus with kernel version 5.4.47), but I need to upgrade the chromium version other than the default version provided by the official yocto recipes on zeus to utilize new chromium features. As a result, I decided to upgrade the built-in system to get newer chromium recipes.

I tried to upgrade the system to kirkstone using the manifest repo. I used the fsl-image-gui recipe to build the system, and migrated the kernel configs using menuconfig. I loaded the device tree of the original old kernel. After deploying the image and filesystem to the board, it boots up normally except the display. It uses a TC358775 chip to convert mipi to lvds, and I got the following errors:

root@imx8mmevk:~# dmesg | grep dsi

[    0.078099] platform 32e10000.mipi_dsi: Fixing up cyclic dependency with 32e00000.lcdif

[    1.306717] imx_sec_dsim_drv 32e10000.mipi_dsi: version number is 0x1060200

[    1.318431] WARNING: CPU: 1 PID: 1 at drivers/gpu/drm/imx/sec_mipi_dsim-imx.c:239 sec_dsim_determine_pll_ref_rate+0x110/0x194

[    1.353212] pc : sec_dsim_determine_pll_ref_rate+0x110/0x194

[    1.358879] lr : sec_dsim_determine_pll_ref_rate+0xc8/0x194

[    1.441702]  sec_dsim_determine_pll_ref_rate+0x110/0x194

[    1.447023]  sec_mipi_dsim_bind+0xe4/0x3ac

[    1.451130]  imx_sec_dsim_bind+0xd4/0x110

[    1.543200] imx_sec_dsim_drv 32e10000.mipi_dsi: failed to set pll ref clock rate

[    1.550614] imx_sec_dsim_drv 32e10000.mipi_dsi: failed to bind sec dsim bridge: -22

[    1.558293] imx-drm soc@0:bus@32c00000:display-subsystem: failed to bind 32e10000.mipi_dsi (ops imx_sec_dsim_ops): -22

[    4.613855] systemd-sysv-generator[191]: SysV service '/etc/init.d/sendsigs' lacks a native systemd unit file. Automatically generating a unit file for compatibility. Please update package to include a native systemd unit file, in order to make it more safe and robust.

Now I am curious about the following points:
1. If the final goal is just to be able to upgrade chromium to any desired version, is this system upgrading necessary? Is there some simpler alternatives?

2. If system upgrading is required, how to I fix my issue? It has been confusing me for months and it is really frustrating.

Thank you so much for reading this post. It would be a great pleasure if someone could provide any solution or clue.

[Zhiming_Liu]

Hello,

1. If the final goal is just to be able to upgrade chromium to any desired version, is this system upgrading necessary? Is there some simpler alternatives?

-->Upgrading the BSP version is the simplest one.

2. If system upgrading is required, how to I fix my issue?

--> Try to compare drivers/gpu/drm/imx/sec_mipi_dsim-imx.c and drivers/clk/imx/clk-pll14xx.c between two version. There should be some difference about display clocks.

Best Regards,
Zhiming