[ Upstream commit 7b38fd9760f51cc83d80eed2cfbde8b5ead9e93a ]
Except for Endpoints, we enable PTM at enumeration-time. Previously we did
not account for the fact that Switch Downstream Ports are not permitted to
have a PTM capability; their PTM behavior is controlled by the Upstream
Port (PCIe r5.0, sec 7.9.16). Since Downstream Ports don't have a PTM
capability, we did not mark them as "ptm_enabled", which meant that
pci_enable_ptm() on an Endpoint failed because there was no PTM path to it.
Mark Downstream Ports as "ptm_enabled" if their Upstream Port has PTM
enabled.
Fixes: eec097d431 ("PCI: Add pci_enable_ptm() for drivers to enable PTM on endpoints")
Reported-by: Aditya Paluri <Venkata.AdityaPaluri@synopsys.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
3facf1adb9