[SPARC64]: Avoid JBUS errors on some Niagara systems.
Doing PCI config space accesses to non-present PCI slots can result in fatal JBUS errors if the PCI config access hypervisor call is performed on cpus other than the boot cpu. PCI config space accesses to present PCI slots works just fine. Recursively traverse the OBP device tree under the PCI controller node and record all present device IDs into a small hash table. Avoid the hypervisor call for any PCI config space access attempt for a device not recorded in the hash table. Signed-off-by: David S. Miller <firstname.lastname@example.org>
Showing with 118 additions and 6 deletions