Some Root Ports on Intel Tiger Lake and Alder Lake systems support the RP
Extensions for DPC and the RP PIO Log registers but incorrectly advertise
an RP PIO Log Size of zero. This means the kernel complains that:
DPC: RP PIO log size 0 is invalid
and if DPC is triggered, the DPC driver will not dump the RP PIO Log
registers when it should.
This is caused by a BIOS bug and should be fixed the BIOS for future CPUs.
Add a quirk to set the correct RP PIO Log size for the affected Root Ports.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=209943
Link: https://lore.kernel.org/r/20220816102042.69125-1-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>