4.19.58 doesn't boot on 3B+

[trilean]

...at least there's no HDMI output.

I'm compiling my own kernels because I'm running Gentoo on my Pi. I have a working config + image for 4.19.25. Using this config on the current tree (rpi-4.19.y/4.19.58) only results in the rainbow pattern on HDMI.

Now I've tested bcmrpi3_defconfig. The only changes are:

• no module support - everything is built in
• built in firmware (CONFIG_EXTRA_FIRMWARE)
• CONFIG_RTL8192CU is not set (wouldn't link)

Still I'm just getting the rainbow pattern. It's the same on 5.2.1.

I'm using:

• DTBs built with my kernel
• latest bootcode.bin / fixup.dat / start.elf
• 64bit kernel + userland

cmdline.txt:

dwc_otg.lpm_enable=0 root=/dev/mmcblk0p2 rootfstype=f2fs elevator=bfq fsck.repair=yes rootwait quiet

config.txt:

gpu_mem=32

dtparam=audio=on
dtparam=spi=on

Any ideas how to debug this?

[lategoodbye]

In case the RPi 3B+ is able to mount the rootfs, there should be the kernel log available under /var/log/kern.log

Another way to debug this issue is to connect a serial TTL adapter to the debug UART (GPIO14,15).

[trilean]

I dug up my USB-serial converter. The serial console works fine. After a couple of reboots the monitor suddenly came to life, but the image was badly distorted. It might be an issue with the hardware. Though if it is I don't understand why it works with an older kernel.