Where is the pxb-pcie device? 0000:$somewhere? Or $domain:00:00.0?
0000:$somewhere (On PCI domain 0)
Cool, so we don't have an chicken-and-egg issue.
If we can access pxb-pcie registers before configuring MMCFG then yes, we should use pxb-pcie registers for that.
Yes, we can.
Ok, so we can configure mmcfg as hidden pci bar, simliar to the q35 mmcfg. Any configuration hints can be passed as pci vendor capability (simliar to the bridge window size hints), if needed.