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PCI/PM: Increase wait time after resume

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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>
This commit is contained in:
Mika Westerberg 2023-04-04 08:27:13 +03:00 committed by Bjorn Helgaas
parent fe15c26ee2
commit e8b908146d
1 changed files with 2 additions and 1 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

3
drivers/pci/pci-driver.c
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@ -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) 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 * When powering on a bridge from D3cold, the whole hierarchy may be
* powered on into D0uninitialized state, resume them to give them a * powered on into D0uninitialized state, resume them to give them a