On Tue, 21 Sept 2021 at 13:00, Wesley Cheng <wcheng@xxxxxxxxxxxxxx> wrote: > > Hi Amit, > > On 9/21/2021 12:04 AM, Amit Pundir wrote: > > Hi Wesley, > > > > On Tue, 21 Sept 2021 at 02:44, Wesley Cheng <wcheng@xxxxxxxxxxxxxx> wrote: > >> > >> Hi Amit, > >> > >> On 9/20/2021 1:45 PM, Amit Pundir wrote: > >>> 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. > >>> > >> > >> I believe Android will attempt a number of bootup sequences and if it > >> fails, it falls back to fastboot mode. Are there any available logs you > >> might be able to collect to see where the issue is? > > > > It is a stock phone with no UART access, so I can't get early crash > > logs unless I'm booted up to adb shell. I can try getting some info > > using pstore-ramoops but warm reset support for sdm845 was not > > upstreamed when I tried using that the last time. > > > > I see, can we maybe avoid the actual resizing by commenting out the > following writel() calls, but let the fifo resize logic calculate the EPs? > > void dwc3_gadget_clear_tx_fifos(struct dwc3 *dwc) > { > ... > /* Don't change TXFRAMNUM on usb31 version */ > size = DWC3_IP_IS(DWC3) ? 0 : > dwc3_readl(dwc->regs, DWC3_GTXFIFOSIZ(num >> 1)) & > DWC31_GTXFIFOSIZ_TXFRAMNUM; > /* Comment the dwc3_writel() */ > //dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(num >> 1), size); > > and > > static int dwc3_gadget_resize_tx_fifos(struct dwc3_ep *dep) > { > ... > /* Comment the dwc3_writel() */ > //dwc3_writel(dwc->regs, DWC3_GTXFIFOSIZ(dep->number >> 1), fifo_size); > dwc->num_ep_resized++; > > Those 2 writel() would be the one that actually programs the TXFIFO > register. I hope when commented out, no resize should actually happen > anymore. > > With this, hopefully we can get some logs from the device at least :) I can boot fine with above 2 writel() removed but I don't see EP counts being printed in the log anywhere and the only relevant message in dmesg I see is this: Duplicate name in dwc3@a600000, renamed to "tx-fifo-resize#1" which is interesting because I don't see tx-fifo-resize property being set by any of the upstream sdm845 or relevant dtsi files. > > >> > >>> 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/ > >>> > >> > >> I assume that you've already confirmed reverting that change resolves > >> the constant reboots? > > > > Yes reverting that change resolves the reboot loop issue. Speaking of > > which, since no other platform seem to be running into this issue and > > "tx-fifo-max-num" property is apparently not at fault either, is it > > reasonable to skip adding "tx-fifo-resize" property for PocoF1 using > > of_machine_is_compatible("xiaomi,beryllium") as a workaround? > > > > Since SDM845 does technically support txfifo resize downstream, let me > see if I can figure out what is different on this particular device > after getting the logs. > > Thanks > Wesley Cheng > > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project
