[Skiboot] Question about PCIe slots in device-tree

[Илья Кузнецов]

Hello,
I'm wondering what is the reason to register only PCIe downstream port of the
switch directly connected to CPU? What if I would like to see third or fourth
switch in chain in the device-tree?
https://github.com/open-power/skiboot/blob/10497d05169fe6e05cecb762a35c63c164469819/core/pcie-slot.c#L551

My question relates to pnv_php kernel driver which checks for capabilities 
through the device-tree.

Thank you!