If according to the instructions , after updating packages and the kernel to the latest versions , there is normal access to SPI immediately from the running image (I use existing scripts that allow you to manage the Erasure and installation of new versions of SPI).
Placing u-boot in SPI allows you to run any system from any media, without having to add your own u-boot to them . For example, it is more convenient for me to have the main system on NVMe and run the rest of the test systems from USB. I donāt need an SD card or eMMC at all. Especially since Iām not interested in Android at all. Android is a disgusting system, full of shit, it does not depend on who collected it and for what device, the idea of Android on TV boxes is idiotic. Android is exclusively for systems with a touchscreen, for controlling your fingers on the screen.