Fix boottime kernel panic on RPi CM5

[gizahNL]

Fixes #1394

This adds the required devicetree and overlays to the raspberrypi5.conf file to allow booting the RPi CM5 without a kernel panic.

Thanks @gokamura for finding the fix.

U-Boot still doesn't work in my testing, waiting to get the uart headers to see if there is some output there.

[agherzan]

Thanks for this. I had a small comment and I'd like to ask you to massage a bit the git log to adhere to https://meta-raspberrypi.readthedocs.io/en/latest/contributing.html (check git history for examples). Thanks!

[stu-spp]

Bump! Can we get these changes merged in please?

[stu-spp]

Wait, won't we also need to update the revision for rpi-bootfiles.bb? Will the current 20240319 have the device tree blobs we need?

Edit:

Oh, I guess it does, but I'm not sure how? Were the dtb files ready to go all the way back in March of 2024? How are these supposedly recently released device tree blobs available all the way back in March 2024? Aren't the blobs made available to the build via recipes-bsp/bootiles/rpi-bootfiles.bb?

x@xps:~$ sudo tree -ash /mntb/ | grep -E "cm5|stamp|2712"
├── [ 79K]  bcm2712-rpi-5-b.dtb
├── [ 80K]  bcm2712-rpi-cm5-cm4io.dtb
├── [ 80K]  bcm2712-rpi-cm5-cm5io.dtb
├── [ 80K]  bcm2712-rpi-cm5l-cm4io.dtb
├── [ 80K]  bcm2712-rpi-cm5l-cm5io.dtb
├── [612K]  kernel_2712.img
│   └── [1.5K]  bcm2712d0.dtbo
├── [   0]  rpi-bootfiles-20240319.stamp
x@xps:~$

[gizahNL]

For the Compute Module 5 (also the Rpi 5 and 4) the bootloader lives in an EEPROM chip, so no update would be needed, as those files aren't needed at all to boot.

EDIT:
The DTB files are created from the Linux Kernel sources (or at least I think they are)

[stu-spp]

U-Boot still doesn't work in my testing, waiting to get the uart headers to see if there is some output there.

I'm trying to get bootdelay=-2 fed down into the build from a kas file. Is that possible? I've only managed to manually recompile u-boot with the correct CONFIG_BOOTDELAY=-2, but I'd rather have something in a kas file that does the configuration.

Is my only option doing a u-boot_%.bbappend in my custom meta layers and then trying to stuff in the extra configuration in a do_configure:append() ? Something like:

do_configure:append() {
    echo "CONFIG_BOOTDELAY=-2" >> ${B}/.config
}

That's annoying that I have to make a whole extra bbappend, and can't simply hit it from my kas file in some way.