On 3/29/2021 3:20 PM, John Stultz wrote: > On Mon, Mar 29, 2021 at 3:15 PM Wesley Cheng <wcheng@xxxxxxxxxxxxxx> wrote: >> >> >> >> On 3/19/2021 4:09 PM, Thinh Nguyen wrote: >>> Wesley Cheng wrote: >>>> >>>> >>>> On 3/8/2021 10:33 PM, Wesley Cheng wrote: >>>>> >>>>> >>>>> On 3/8/2021 7:05 PM, Thinh Nguyen wrote: >>>>>> Wesley Cheng wrote: >>>>>>> >>>>>>> On 3/6/2021 3:41 PM, Thinh Nguyen wrote: >>>>>>>> Wesley Cheng wrote: >>>>>>>>> On 1/8/2021 4:44 PM, Thinh Nguyen wrote: >>>>>>>>>> Hi, >>>>>>>>>> >>>>>>>>>> John Stultz wrote: >>>>>>>>>>> On Fri, Jan 8, 2021 at 4:26 AM Felipe Balbi <balbi@xxxxxxxxxx> wrote: >>>>>>>>>>>> Hi, >>>>>>>>>>>> >>>>>>>>>>>> John Stultz <john.stultz@xxxxxxxxxx> writes: >>>>>>>>>>>>> From: Yu Chen <chenyu56@xxxxxxxxxx> >>>>>>>>>>>>> >>>>>>>>>>>>> Just resending this, as discussion died out a bit and I'm not >>>>>>>>>>>>> sure how to make further progress. See here for debug data that >>>>>>>>>>>>> was requested last time around: >>>>>>>>>>>>> https://urldefense.com/v3/__https://lore.kernel.org/lkml/CALAqxLXdnaUfJKx0aN9xWwtfWVjMWigPpy2aqsNj56yvnbU80g@xxxxxxxxxxxxxx/__;!!A4F2R9G_pg!LNzuprAeg-O80SgolYkIkW4-ne-M-yLWCDUY9MygAIrQC398Z6gRJ9wnsnlqd3w$ >>>>>>>>>>>>> >>>>>>>>>>>>> With the current dwc3 code on the HiKey960 we often see the >>>>>>>>>>>>> COREIDLE flag get stuck off in __dwc3_gadget_start(), which >>>>>>>>>>>>> seems to prevent the reset irq and causes the USB gadget to >>>>>>>>>>>>> fail to initialize. >>>>>>>>>>>>> >>>>>>>>>>>>> We had seen occasional initialization failures with older >>>>>>>>>>>>> kernels but with recent 5.x era kernels it seemed to be becoming >>>>>>>>>>>>> much more common, so I dug back through some older trees and >>>>>>>>>>>>> realized I dropped this quirk from Yu Chen during upstreaming >>>>>>>>>>>>> as I couldn't provide a proper rational for it and it didn't >>>>>>>>>>>>> seem to be necessary. I now realize I was wrong. >>>>>>>>>>>>> >>>>>>>>>>>>> After resubmitting the quirk, Thinh Nguyen pointed out that it >>>>>>>>>>>>> shouldn't be a quirk at all and it is actually mentioned in the >>>>>>>>>>>>> programming guide that it should be done when switching modes >>>>>>>>>>>>> in DRD. >>>>>>>>>>>>> >>>>>>>>>>>>> So, to avoid these !COREIDLE lockups seen on HiKey960, this >>>>>>>>>>>>> patch issues GCTL soft reset when switching modes if the >>>>>>>>>>>>> controller is in DRD mode. >>>>>>>>>>>>> >>>>>>>>>>>>> Cc: Felipe Balbi <balbi@xxxxxxxxxx> >>>>>>>>>>>>> Cc: Tejas Joglekar <tejas.joglekar@xxxxxxxxxxxx> >>>>>>>>>>>>> Cc: Yang Fei <fei.yang@xxxxxxxxx> >>>>>>>>>>>>> Cc: YongQin Liu <yongqin.liu@xxxxxxxxxx> >>>>>>>>>>>>> Cc: Andrzej Pietrasiewicz <andrzej.p@xxxxxxxxxxxxx> >>>>>>>>>>>>> Cc: Thinh Nguyen <thinhn@xxxxxxxxxxxx> >>>>>>>>>>>>> Cc: Jun Li <lijun.kernel@xxxxxxxxx> >>>>>>>>>>>>> Cc: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> >>>>>>>>>>>>> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> >>>>>>>>>>>>> Cc: linux-usb@xxxxxxxxxxxxxxx >>>>>>>>>>>>> Signed-off-by: Yu Chen <chenyu56@xxxxxxxxxx> >>>>>>>>>>>>> Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx> >>>>>>>>>>>>> --- >>>>>>>>>>>>> v2: >>>>>>>>>>>>> * Rework to always call the GCTL soft reset in DRD mode, >>>>>>>>>>>>> rather then using a quirk as suggested by Thinh Nguyen >>>>>>>>>>>>> >>>>>>>>>>>>> v3: >>>>>>>>>>>>> * Move GCTL soft reset under the spinlock as suggested by >>>>>>>>>>>>> Thinh Nguyen >>>>>>>>>>>> Because this is such an invasive change, I would prefer that we get >>>>>>>>>>>> Tested-By tags from a good fraction of the users before applying these >>>>>>>>>>>> two changes. >>>>>>>>>>> I'm happy to reach out to folks to try to get that. Though I'm >>>>>>>>>>> wondering if it would be better to put it behind a dts quirk flag, as >>>>>>>>>>> originally proposed? >>>>>>>>>>> https://urldefense.com/v3/__https://lore.kernel.org/lkml/20201021181803.79650-1-john.stultz@xxxxxxxxxx/__;!!A4F2R9G_pg!LNzuprAeg-O80SgolYkIkW4-ne-M-yLWCDUY9MygAIrQC398Z6gRJ9wnRWITZfc$ >>>>>>>>>>> >>>>>>>>>>> That way folks can enable it for devices as they need? >>>>>>>>>>> >>>>>>>>>>> Again, I'm not trying to force this in as-is, just mostly sending it >>>>>>>>>>> out again for discussion to understand what other approach might work. >>>>>>>>>>> >>>>>>>>>>> thanks >>>>>>>>>>> -john >>>>>>>>>> A quirk would imply something is broken/diverged from the design right? >>>>>>>>>> But it's not the case here, and at least this is needed for HiKey960. >>>>>>>>>> Also, I think Rob will be ok with not adding 1 more quirk to the dwc3 >>>>>>>>>> devicetree. :) >>>>>>>>>> >>>>>>>>>> BR, >>>>>>>>>> Thinh >>>>>>>>>> >>>>>>>>> Hi All, >>>>>>>>> >>>>>>>>> Sorry for jumping in, but I checked the SNPS v1.90a databook, and that >>>>>>>>> seemed to remove the requirement for the GCTL.softreset before writing >>>>>>>>> to PRTCAPDIR. Should we consider adding a controller version/IP check? >>>>>>>>> >>>>>>>> Hi Wesley, >>>>>>>> >>>>>>>> From what I see in the v1.90a databook and others, the flow remains the >>>>>>>> same. I need to check internally, but I'm not aware of the change. >>>>>>>> >>>>>>> Hi Thinh, >>>>>>> >>>>>>> Hmmm, can you help check the register description for the PRTCAPDIR on >>>>>>> your v1.90a databook? (Table 1-19 Fields for Register: GCTL (Continued) >>>>>>> Pg73) When we compared the sequence in the description there to the >>>>>>> previous versions it removed the GCTL.softreset. If it still shows up >>>>>>> on yours, then maybe my v1.90a isn't the final version? >>>>>>> >>>>>>> Thanks >>>>>>> Wesley Cheng >>>>>>> >>>>>> >>>>>> Hi Wesley, >>>>>> >>>>>> Actually your IP version type may use the newer flow. Can you print your >>>>>> DWC3_VER_TYPE? I still need to verify internally to know which versions >>>>>> need the update if any. >>>>>> >>>>>> Thanks, >>>>>> Thinh >>>>>> >>>>> Hi Thinh, >>>>> >>>>> Sure, my DWC3_VER_TYPE output = 0x67612A2A >>>>> >>>>> Thanks >>>>> Wesley Cheng >>>>> >>>> Hi Thinh, >>>> >>>> Would you happen to have an update on the required sequence on the >>>> version shared? Sorry for pushing, but we just wanted to finalize on >>>> it, since it does cause some functional issues w/o the soft reset in >>>> place, and causes a crash if we have the GCTL.softreset. >>>> >>>> Thanks >>>> Wesley Cheng >>>> >>> >>> Hi Wesley, >>> >>> I'm still trying to get that info for you. The versions without >>> GCTL.softreset should be very new. The flow with GCTL.softreset should >>> work for all versions and should not cause functional impact. We can >>> create a change to optimize and remove GCTL.softreset for the newer >>> controller versions at a later time. >>> >>> Since you and John Stultz have the setup that can be verified in the >>> real world. It would be great if John or you provide a tested patch(es) >>> to resolve this issue. >>> >>> Thanks, >>> Thinh >>> >> Hi Thinh, >> >> Thanks for the input as always. I tested the GCTL.softreset change just >> now, and it is working fine at least on my set up. >> >> Not sure if we'd need input from other vendors as well to get this >> change merged. > > Did you test the original patch from this thread unchanged, or did you > have any modifications? If the latter, feel free to send it out and > I'll validate it on my side. > > thanks > -john > Hi John, I'm using your change as is. Didn't make any modifications to it. Thanks Wesley Cheng -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project
