5.3.7 64-bits kernel doesn't boot on G5 Quad

[Romain Dolbeau <romain@dolbeau.org>]

Hello,

The current linux-image package (5.3.7-1) in debian-ports won't boot
on my G5 Quad (dual 970MP).
I'm currently running the powerpc ports (32 bits userland), not ppc64,
but I assume it makes no difference for the 64 bits kernel.

I have the same error as previously reported for 5.2.7 in:
<https://lists.debian.org/debian-powerpc/2019/08/msg00004.html>

Kernel packages:

#####
powermacg5:~$ dpkg -l linux-image-*
(...)
ii  linux-image-4.19.0-5-powerpc64      4.19.37-5              powerpc
     Linux 4.19 for 64-bit PowerPC
ii  linux-image-4.9.0-0.bpo.6-powerpc64 4.9.88-1+deb9u1~bpo8+1 powerpc
     Linux 4.9 for 64-bit PowerPC
ii  linux-image-5.3.0-1-powerpc64       5.3.7-1                powerpc
     Linux 5.3 for 64-bit PowerPC
#####

linux-image-4.9.0-0.bpo.6-powerpc64 is from jessie-backports,
linux-image-4.19.0-5-powerpc64 is from the Fienix repository (can't
find a Debian build for ppc64 between 4.9 and 5.3).
Both works perfectly on the G5.

Any suggestion on how to identify/fix the bug ?

Thanks in advance & cordially,

-- 
Romain Dolbeau