How to move to a newer Raspberry Pi model without a full reinstall

Question

I just tried booting a Pi 3 with the OSMC image I'd been using on a Pi 1 Model B. The green LED lit up once briefly, no other reaction. I ended up backing up the config and restoring it to a fresh install but I'd like to know if there's an easier way, as I might have other Pis to upgrade in the future. (The other Pis run Raspbian.)

I came across this post – a comment to the accepted answer states that the only difference between Pi models is the kernel – as long as the SD card has both kernels, it will boot fine in both models. Caveats apply if you use the GPIO pins, which I don't – hence nothing to worry about here.

In my case, apparently, the card had only the kernel for the Pi 1 Model B, but not for the Pi 3.

• How can I determine which Pi models the kernels on a given SD card are for?
• If the kernel for a particular model is missing, is there an easy way to add it?

Answer 1

With Linux distributions, the normal way to update is sudo apt update && sudo apt upgrade which updates firmware, although for some dist-upgrade is needed.

All Linux distributions for the Pi use the same kernels (although there are some customised kernels with proprietary drivers). The latest kernel should be OK for all Pi, but beware of rpi-update which may install untested code.

NOTE you NEED more than the kernel7.img file you MUST also have the matching /lib/modules and device tree.

OSMC actually has different downloads for the Pi2/3. I am not sure of the differences - apart from the different memory map, they probably are compiled for ARM7.

Answer 2

Having tried the same with a Raspbian setup, my takeaway is: it depends on the distribution.

Ripping a Raspbian SD out of a Pi 1 and plugging it into a Pi 3 worked for me. For OSMC it didn’t—apparently you really need to download the Pi 3 build (OSMC has a way to back up all your settings and restore them on a fresh install, so it isn't all that much work).