RPI4 stable channel now officially supports USB boot

[johnodon]

No need to muck with 'beta' channel. As always, be aware that not all USB connected devices are supported.

[muldjord]

@johnodon I was just going to post about this, as I didn't know it had left beta. I haven't tried it yet, not even when it was in beta, but I purchased a USB->sata adapter that works well when mount an SSD through it from RetroPie installed on an SD card. So now I'll probably move the entire install to the sata SSD entirely.

EDIT: It seems they haven't updated all of the documentation yet. The following link still says it's beta. I wonder if they forgot, or there's a reason...

https://github.com/raspberrypi/documentation/blob/master/hardware/raspberrypi/booteeprom.md#usb-boot

EDIT2: It seems to be because of a beta GPU firmware that is required for MSD to work. So the EEPROM update with MSD in it is stable, but MSD as a whole, as it requires that GPU fw update, is not.

[mitu]

@muldjord The EEPROM update that enables USB MSD is marked as 'stable', but by default the rpi-eeprom utility only updates the 'critical' releases.
The changelog is here, if you change the update channel from 'critical' to 'stable', you can update it and enable USB boot - https://www.raspberrypi.org/documentation/hardware/raspberrypi/booteeprom.md.

[muldjord]

@mitu Thank you for the clarification.