kernel: set CONFIG_ARCH_TEGRA_210

[RiRa12621]

set CONFIG_ARCH_TEGRA_210

Jetson Nano Developer Kits are using Tegra 210 SoCs, this PR enables that in Flatcar.

The Goal is to test flatcar on jetson nano developer kit. (note the "old" developer kit, not the Orin)

Kernel support should exist already: torvalds/linux@6772cd0

How to use

Not 100% clear yet, will add instructions.
The issue is that the Jetson uses u-boot and probably requires some more steps, but enabling CONFIG_ARCH_TEGRA_210 is step one. Once the image is built, further testing is possible

Testing done

Tests to follow after the generated image is available

• Changelog entries added in the respective changelog/ directory (user-facing change, bug fix, security fix, update)
• Inspected CI output for image differences: /boot and /usr size, packages, list files for any missing binaries, kernel modules, config files, kernel modules, etc.

[sambonbonne]

FYI, I don't know if it can help you but I saw some Tegra 210 configuration while working on my PR for Odroid M1S (Rockchip). I took the Home Assistant OS kernel configuration and I'm trying to use it to build Flatcar.

I had some "missing firmware" due to existing (and enabled) Tegra 210 configuration so I removed those but here they are in case you need it:

CONFIG_ARCH_TEGRA_210_SOC=y
CONFIG_SPI_TEGRA210_QUAD=m
CONFIG_PINCTRL_TEGRA210=y
CONFIG_SND_SOC_TEGRA210_AHUB=m                                                                                                                                 
CONFIG_SND_SOC_TEGRA210_DMIC=m                                                                                                                                 
CONFIG_SND_SOC_TEGRA210_I2S=m                                                                                                                                  
CONFIG_SND_SOC_TEGRA210_OPE=m                                                                                                                                  
CONFIG_SND_SOC_TEGRA210_ADMAIF=m                                                                                                                               
CONFIG_SND_SOC_TEGRA210_MVC=m                                                                                                                                  
CONFIG_SND_SOC_TEGRA210_SFC=m                                                                                                                                  
CONFIG_SND_SOC_TEGRA210_AMX=m                                                                                                                                  
CONFIG_SND_SOC_TEGRA210_ADX=m                                                                                                                                  
CONFIG_SND_SOC_TEGRA210_MIXER=m
CONFIG_TEGRA210_ADMA=m
# CONFIG_TEGRA210_EMC is not set

Again, I'm not sure you'll need any of these configs but if you have some problems to boot an image with CONFIG_ARCH_TEGRA_210 enabled, you may want to try these things. Use with caution, some need a specific firmware (otherwise I guess I wouldn't have had "Missing firmware" errors).

Note: I'm not a Flatcar maintainer, I just have my own SBC PR opened and seeing yours after removing some Tegra 210 config made me think this list could be useful.