Re: [PATCH 0/4] Verify devices transition from D3cold to D0

From: Mario Limonciello
Date: Mon Jul 08 2024 - 23:07:23 EST


On 6/13/2024 0:42, Mario Limonciello wrote:
Gary has reported that when a dock is plugged into a system at the same
time the autosuspend delay has tripped that the USB4 stack malfunctions.

Messages show up like this:

```
thunderbolt 0000:e5:00.6: ring_interrupt_active: interrupt for TX ring 0 is already enabled
```

Furthermore the USB4 router is non-functional at this point.

Those messages happen because the device is still in D3cold at the time
that the PCI core handed control back to the USB4 connection manager
(thunderbolt).

The issue is that it takes time for a device to enter D3cold and do a
conventional reset, and then more time for it to exit D3cold.

This appears not to be a new problem; previously there were very similar
reports from Ryzen XHCI controllers. Quirks were added for those.
Furthermore; adding extra logging it's apparent that other PCI devices
in the system can take more than 10ms to recover from D3cold as well.

This series add a wait into pci_power_up() specifically for D3cold exit and
then drops the quirks that were previously used for the Ryzen XHCI controllers.

Mario Limonciello (4):
PCI: Check PCI_PM_CTRL instead of PCI_COMMAND in pci_dev_wait()
PCI: Verify functions currently in D3cold have entered D0
PCI: Allow Ryzen XHCI controllers into D3cold and drop delays
PCI: Drop Radeon quirk for Macbook Pro 8.2

drivers/pci/pci.c | 21 ++++++++++++++++-----
drivers/pci/quirks.c | 25 -------------------------
drivers/usb/host/xhci-pci.c | 11 -----------
3 files changed, 16 insertions(+), 41 deletions(-)


Bjorn, Mathias,

Any feedback for this series? I did check and it still applies to 6.10-rc7 as is, but if you want me to rebase on linux-pci happy to do so.

At least Mika and I seem in agreement from other comments in the thread on this directionally.

Thanks,