PCI/PM: Increase wait time after resume
authorMika Westerberg <mika.westerberg@linux.intel.com>
Tue, 4 Apr 2023 05:27:13 +0000 (08:27 +0300)
committerBjorn Helgaas <bhelgaas@google.com>
Tue, 11 Apr 2023 22:35:02 +0000 (17:35 -0500)
PCIe r6.0 sec 6.6.1 prescribes that a device must be able to respond to
config requests within 1.0 s (PCI_RESET_WAIT) after exiting conventional
reset and this same delay is prescribed when coming out of D3cold (as that
involves reset too).

A device that requires more than 1 second to initialize after reset may
respond to config requests with Request Retry Status completions (sec
2.3.1), and we accommodate that in Linux with a 60 second cap
(PCIE_RESET_READY_POLL_MS).

Previously we waited up to PCIE_RESET_READY_POLL_MS only in the reset code
path, not in the resume path.  However, a device has surfaced, namely Intel
Titan Ridge xHCI, which requires a longer delay also in the resume code
path.

Make the resume code path to use this same extended delay as the reset
path.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216728
Link: https://lore.kernel.org/r/20230404052714.51315-2-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>
Cc: Lukas Wunner <lukas@wunner.de>
drivers/pci/pci-driver.c

index 57ddcc59af3047970cbf143867b386cb8365ef05..6b5b2a818e65c9b907a99349f37a0e621a28aedb 100644 (file)
@@ -572,7 +572,8 @@ static void pci_pm_default_resume_early(struct pci_dev *pci_dev)
 
 static void pci_pm_bridge_power_up_actions(struct pci_dev *pci_dev)
 {
-       pci_bridge_wait_for_secondary_bus(pci_dev, "resume", PCI_RESET_WAIT);
+       pci_bridge_wait_for_secondary_bus(pci_dev, "resume",
+                                         PCIE_RESET_READY_POLL_MS);
        /*
         * When powering on a bridge from D3cold, the whole hierarchy may be
         * powered on into D0uninitialized state, resume them to give them a