Variscite VAR-SOM-MX8

[cbrake]

(this first entry will be updated over time with summary information about how to use the VAR-SOM-MX8)

The VAR-SOM-MX8 family is i.MX8 SOM from Variscite.

The following image shows initial hookup:

SW3 can be used to switch between eMMC and SD boot. When booting from eMMC, you will see Boot: MMC0, with SD Boot: SD1.

To boot Yoe:

• source your favorite imx8... machine envsetup file

• build an image (yoe-simple-image, yoe-kiosk-image, etc)

• Program the build/tmp/deploy/images/<machine>/<image>.wic.xz image to your SD card using etcher or yoe_install_image tool

  yoe_install_image /dev/sdX yoe-kiosk-image
  

  where X is letter that SD card is assigned e.g. /dev/sda or /dev/sdb etc.

• select SD boot (see image above)

• insert the SD card and power on

[cbrake]

Working on VAR-SOM-MX8 support here:

mx8 tests

Almost building:

Thanks to @khem for keeping meta-freescale current with Yocto/Yoe master branch.

cc @collinbrake

[khem]

if we disable updater then then we can build SD card wic image. Updater for imx8 will need some work as it seems, which we expected.

[khem]

I got image (without updater) built for imx8qm-var-som

For a challange I said lets try with

YOE_PROFILE ?= "yoe-musl-systemd-wayland"

and it all came along nicely. Ofcourse I have patches for meta-freescale proposed already for merge.

[cbrake]

Great progress! Now, to figure out how load up an SD card for this thing …

[cbrake]

Loaded yoe-simple-image wic file on a SD card and it boots:

Yoe Linux 2022.08 imx8qxp-var-som ttyLP3
imx8qxp-var-som login: root
root@imx8qxp-var-som:~# 

Next, working on LVGL recipe for their demo app, and trying some other graphical stuff …

[cbrake]

Build and installed yoe-kiosk-image, and weston/wayland is working. Also appears egl tests are working:

root@imx8qxp-var-som:~# export XDG_RUNTIME_DIR=/run
root@imx8qxp-var-som:~# export WAYLAND_DISPLAY=wayland-0
root@imx8qxp-var-som:~# weston-simple-dmabuf-egl
root@imx8qxp-var-som:~# weston-simple-egl 
has EGL_EXT_buffer_age and EGL_EXT_swap_buffers_with_damage
302 frames in 5 seconds: 60.400002 fps
301 frames in 5 seconds: 60.200001 fps

[cbrake]

The LVGL demo is also running on this device now.

[cbrake]

The i.MX8X CPU I’m using here does not have a heatsink installed yet (it came with one). I’m not pushing it hard right now, and the case is warm – just under the threshold of being too hot to keep my finger on it for a long time – probably just under 50degC. MX8 devices will definitely need some thought in the thermal design, unlike the i.MX6UL which runs cool. Heatsinking to a metal case is probably a good option.

[khem]

I have observed that all arm64 cores based CPUs run hotter compared to 32bit ones and I do agree a better heatsink mechanism would go long way.

[cbrake]

VAR-SOM-MX8x support has been merged into yoe/master. @collinbrake give it a try and let us know how it goes. I’ve added instructions for flashing SD card above. Will work on the updater next so we can program eMMC.

[khem]

on my MX8 I am seeing a core is offline and I wonder why

[cbrake]

only have 4 cores on unit here:

The original image might still be in flash, you could try booting that and see if you see the same thing.

[cbrake]

This is an interesting discussion:

disabling cpu cores on quad core processor on linux