PCI: Distribute available resources for root buses, too

Previously we distributed spare resources only upon hot-add, so if the
initial root bus scan found devices that had not been fully configured by
the BIOS, we allocated only enough resources to cover what was then
present. If some of those devices were hotplug bridges, we did not leave
any additional resource space for future expansion.

Distribute the available resources for root buses, too, to make this work
the same way as the normal hotplug case.

A previous commit to do this was reverted due to a regression reported by
Jonathan Cameron:

  e96e27fc6f79 ("PCI: Distribute available resources for root buses, too")
  5632e2beaf9d ("Revert "PCI: Distribute available resources for root buses, too"")

This commit changes pci_bridge_resources_not_assigned() to work with
bridges that do not have all the resource windows programmed by the boot
firmware (previously we expected all I/O, memory and prefetchable memory
were programmed).

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216000
Link: https://lore.kernel.org/r/20220905080232.36087-5-mika.westerberg@linux.intel.com
Link: https://lore.kernel.org/r/20230131092405.29121-4-mika.westerberg@linux.intel.com
Reported-by: Chris Chiu <chris.chiu@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

0 files changed, 0 insertions, 0 deletions