linux-phytec-fsl

x86/PCI: Work around AMD Fam15h BIOSes that fail to provide _PXM

The BIOS is supposed to provide ACPI _PXM methods for PCI host bridges if
it cares about platform topology.  But some BIOSes do not, so add Fam15h
to the list of CPUs for which we fall back to reading node numbers from the
hardware.

Note that pci_acpi_scan_root() warns about the BIOS bug if we use this
information because (1) the hardware node numbers are not necessarily
compatible with other logical node numbers from ACPI, and (2) the lack of
_PXM forces OS updates that would not otherwise be required.

[bhelgaas: changelog, comments]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=72051
Tested-by: Aravind Gopalakrishnan <Aravind.Gopalakrishnan@amd.com>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Robert Richter <rric@kernel.org>
Cc: Daniel J Blueman <daniel@numascale.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>