PCI enumeration issue with QCA9590 (ath9k driver) + imx8mp evb with 6.1.55

[govindsi]

I am seeing 2 potential issue with QCA9590 (ath9k driver) + imx8mp evb with 6.1.55(imx-linux)

1) Enumeration fails 1/10 time.

2) Upon successful enumeration, while connecting to an AP,  beacon miss issue is seen. This is leading to disconnection periodically.

nl80211: Event message available nl80211: Drv Event 64 (NL80211_CMD_NOTIFY_CQM) received for wlp1s0 nl80211: Beacon loss event wlp1s0: Event BEACON_LOSS (53) received wlp1s0: CTRL-EVENT-BEACON-LOSS Is three any known regression in ath9k driver with >= 6.1.55 kernel.

Is there any known issue/regression already found in the baseline.

[govindsi]

With more trails the problem is linked to legacy interrupt handling on Designware PCIe core ( imx8mp) when MSI is enabled.

Currently , i am able to make it work with downgrading the link speed to Gen1 and disabling MSI @ "pci=nomsi"

Still checking if only disable MSI can solve this issue as there has been some of the threads in kernel mainline indicating the same.

https://lore.kernel.org/linux-pci/1551261667.2305.6.camel@pengutronix.de/

https://community.nxp.com/t5/i-MX-Processors/i-MX6-7-Pcie-legacy-interrupt/m-p/730464

https://lore.kernel.org/all/CAD8Lp44c1k-xP1U9X8PR_kw=8joMY8RUwcKVBvuWaV7faNhWZg@mail.gmail.com/T/

https://www.spinics.net/lists/linux-wireless/msg233927.html

[JosephAtNXP]

Hi,

Thank you for your interest in NXP Semiconductor products,

We have not tested QCA chipset, and the experiment would be an issue of the power supply used, that doesn't power cycle often the QCA right or it isn't stable.

Also, updating the driver used might help in this issue.

Regards