The iommu is missing from your dmesg, so I guess the bios does not remap
the memory to give space for the pci configuration. This would result in
the symptoms described in the dmesg.
The output from the boot promt "machine memory" will show if I am right
with the above. If so, take a look into the bios options. There should be
a knob which should take care of the remapping. If there is no such knob
you should look for a bios update.