dwc3-qcom: tx-fifo-resize regression on Poco F1 (sdm845) with v5.15-rc1

From: Amit Pundir
Date: Mon Sep 20 2021 - 21:43:20 EST


Hi Wesley, All,

I see a reboot loop on Xiaomi Pocophone F1 (sdm845) with TX FIFO
resize patches which landed in v5.15-rc1. Upstream commit cefdd52fa045
"usb: dwc3: dwc3-qcom: Enable tx-fifo-resize property by default" to
be specific, which switched on this feature by default.

At times the phone crashes into the fastboot mode after the reboot
loop, but mostly end up booting to UI after a while. This is what it
looks like https://people.linaro.org/~amit.pundir/beryllium-userdebug/PXL_20210920_162749483.mp4.

PocoF1 does support TX fifo resizing as I can see that in the
downstream dts. So maybe it is the tx-fifo-max-num which need to be
adjusted for the device? I couldn't find the tx-fifo-max-num
equivalent in the downstream tree though
https://github.com/MiCode/Xiaomi_Kernel_OpenSource/tree/dipper-q-oss/

Curious if you had any ideas what might be going wrong? For now I'll
keep digging around tx-fifo-max-num, but I figured I'd ask just in
case it's obvious to you.

Regards,
Amit Pundir