Xen 4.14.1 on RPI4: device tree generation failed

[Tamas K Lengyel <tamas.k.lengyel@xxxxxxxxx>]

Hi all,
I'm trying to boot Xen 4.14.1 on my RPI4 with the 5.10 kernel, built
using https://github.com/tklengyel/xen-rpi4-builder/tree/update.
Everything builds fine and Xen boots but then I get this error:

(XEN) *** LOADING DOMAIN 0 ***
(XEN) Loading d0 kernel from boot module @ 0000000000480000
(XEN) Allocating 1:1 mappings totalling 2048MB for dom0:
(XEN) BANK[0] 0x00000008000000-0x00000028000000 (512MB)
(XEN) BANK[1] 0x00000030000000-0x00000038000000 (128MB)
(XEN) BANK[2] 0x00000080000000-0x000000c0000000 (1024MB)
(XEN) BANK[3] 0x000000d8000000-0x000000f0000000 (384MB)
(XEN) Grant table range: 0x00000000200000-0x00000000240000
(XEN) Unable to retrieve address 0 for /scb/pcie@7d500000/pci@1,0/usb@1,0
(XEN) Device tree generation failed (-22).
(XEN)
(XEN) ****************************************
(XEN) Panic on CPU 0:
(XEN) Could not set up DOM0 guest OS
(XEN) ****************************************
(XEN)
(XEN) Reboot in five seconds...


Does anyone have an idea what might be going wrong here? I tried
building the dtb without using the dtb overlay but it didn't seem to
do anything.

Thanks,
Tamas