dom0 LInux 5.8-rc5 kernel failing to initialize cooling maps for Allwinner H6 SoC

[Alejandro <alejandro.gonzalez.correo@gmail.com>]

Hello all.

I'm new to this community, and firstly I'd like to thank you all for
your efforts on supporting Xen in ARM devices.

I'm trying Xen 4.13.1 in a Allwinner H6 SoC (more precisely a Pine H64
model B, with a ARM Cortex-A53 CPU).
I managed to get a dom0 Linux 5.8-rc5 kernel running fine, unpatched,
and I'm using the upstream device tree for
my board. However, the dom0 kernel has trouble when reading some DT
nodes that are related to the CPUs, and
it can't initialize the thermal subsystem properly, which is a kind of
showstopper for me, because I'm concerned
that letting the CPU run at the maximum frequency without watching out
its temperature may cause overheating.
The relevant kernel messages are:

[  +0.001959] sun50i-cpufreq-nvmem: probe of sun50i-cpufreq-nvmem
failed with error -2
...
[  +0.003053] hw perfevents: failed to parse interrupt-affinity[0] for pmu
[  +0.000043] hw perfevents: /pmu: failed to register PMU devices!
[  +0.000037] armv8-pmu: probe of pmu failed with error -22
...
[  +0.000163] OF: /thermal-zones/cpu-thermal/cooling-maps/map0: could
not find phandle
[  +0.000063] thermal_sys: failed to build thermal zone cpu-thermal: -22

I've searched for issues, code or commits that may be related for this
issue. The most relevant things I found are:

- A patch that blacklists the A53 PMU:
https://patchwork.kernel.org/patch/10899881/
- The handle_node function in xen/arch/arm/domain_build.c:
https://github.com/xen-project/xen/blob/master/xen/arch/arm/domain_build.c#L1427

I've thought about removing "/cpus" from the skip_matches array in the
handle_node function, but I'm not sure
that would be a good fix.

I'd appreciate any tips for fixing this issue. Don't hesitate to
contact me back if you need any more information
about the problem.