On Thu, Mar 04, 2021 at 12:29:08PM -0600, Bjorn Helgaas wrote: > That's not much to go on. Someone with more knowledge of the actual > problem would have to weigh in on whether hiding a device is the best > approach. Since Pali asked.. The issue with this HW is the IP designers took an end port PCIe core and glued it up to act as a root port without changing anything. This is why it doesn't present a bridge config space. It is a *completely* non compliant design. The pci-mvebu host bridge driver is designged to fix this. It provides a compliant PCI register view for a root port device using SW to inspect config space operations and remaps the config space accesses to their non-compliant positions within the SOC. Hoping that the PCI core can directly drive this PCI device as a root port without the above driver is just an endless sea of hacks. Jason
