Messages in this thread | | | Subject | Re: [PATCH v10 0/6] Re-introduce TX FIFO resize for larger EP bursting | From | Pavel Hofman <> | Date | Tue, 24 Aug 2021 07:39:32 +0200 |
| |
Dne 24. 08. 21 v 0:50 Thinh Nguyen napsal(a): > Pavel Hofman wrote: >> >> >> Dne 23. 08. 21 v 17:21 Andy Shevchenko napsal(a): >>> On Mon, Aug 23, 2021 at 5:59 PM Pavel Hofman >>> <pavel.hofman@ivitera.com> wrote: >>>> Dne 22. 08. 21 v 21:43 Ferry Toth napsal(a): >>>>> Op 19-08-2021 om 23:04 schreef Pavel Hofman: >>>>>> Dne 19. 08. 21 v 22:10 Ferry Toth napsal(a): >>>>>>> Op 19-08-2021 om 09:51 schreef Pavel Hofman: >>>>>>>> Dne 18. 08. 21 v 21:07 Ferry Toth napsal(a): >>>>>>>>> Op 18-08-2021 om 00:00 schreef Ferry Toth: >>> >>> ... >>> >>>>>>>>> So, where do we go from here? >>>>>>>> >>>>>>>> I know the patches have been tested on dwc2 (by me and others). I >>>>>>>> do not know if Ruslan or Jerome tested them on dwc3 but probably >>>>>>>> not. Ruslan has talked about RPi (my case too) and BeagleboneBlack, >>>>>>>> both with dwc2. Perhaps the dwc2 behaves a bit differently than >>>>>>>> dwc3? >>>>>>>> >>>>>>>> The patches add a new EP-IN for async feedback. I am sorry I have >>>>>>>> not followed your long thread (it started as unrelated to uac). Does >>>>>>>> the problem appear with f_uac1 or f_uac2? Please how have you >>>>>>>> reached the above problem? >>>>>>> >>>>>>> I'm sorry too. I first believed the issue was related to the patch >>>>>>> mentioned in the subject line. >>>>>>> >>>>>>> The problem appaers with f_uac2. I bost Edison_Arduino board in host >>>>>>> mode (there is a switch allowing to select host/device mode). When >>>>>>> flipping the switch to device mode udev run a script: >>>>>>> But as I am using configfs (excerpt follows) and just disabling the >>>>>>> last 2 line resolves the issue, I'm guessing uac2 is the issue. Or >>>>>>> exceeding the available resources. >>>>>>> >>>>>>> # Create directory structure >>>>>>> mkdir "${GADGET_BASE_DIR}" >>>>>>> cd "${GADGET_BASE_DIR}" >>>>>>> mkdir -p configs/c.1/strings/0x409 >>>>>>> mkdir -p strings/0x409 >>>>>>> >>>>>>> # Serial device >>>>>>> mkdir functions/gser.usb0 >>>>>>> ln -s functions/gser.usb0 configs/c.1/ >>>>>>> ### >>>>>>> >>>>>>> # Ethernet device >>>>>>> mkdir functions/eem.usb0 >>>>>>> echo "${DEV_ETH_ADDR}" > functions/eem.usb0/dev_addr >>>>>>> echo "${HOST_ETH_ADDR}" > functions/eem.usb0/host_addr >>>>>>> ln -s functions/eem.usb0 configs/c.1/ >>>>>>> >>>>>>> # Mass Storage device >>>>>>> mkdir functions/mass_storage.usb0 >>>>>>> echo 1 > functions/mass_storage.usb0/stall >>>>>>> echo 0 > functions/mass_storage.usb0/lun.0/cdrom >>>>>>> echo 0 > functions/mass_storage.usb0/lun.0/ro >>>>>>> echo 0 > functions/mass_storage.usb0/lun.0/nofua >>>>>>> echo "${USBDISK}" > functions/mass_storage.usb0/lun.0/file >>>>>>> ln -s functions/mass_storage.usb0 configs/c.1/ >>>>>>> >>>>>>> # UAC2 device >>>>>>> mkdir functions/uac2.usb0 >>>>>>> ln -s functions/uac2.usb0 configs/c.1 >>>>>>> .... >>>>>> >>>>>> As you say, could perhaps the reason be that the extra EP-IN added in >>>>>> those patches (previously 1, now 2 with the default config you use) >>>>>> exceeds your EP-IN max count or available fifos somehow? You have a >>>>>> number of functions initialized. If you change the load order of the >>>>>> functions, do you get the error later with a different function? Just >>>>>> guessing... >>>>>> >>>>>> You should be able to switch the default async EP-OUT (which >>>>>> configures the new feedback EP-IN ) to adaptive EP-OUT (which requires >>>>>> no feedback EP) with c_sync=8 parameter of f_uac2. >>>>>> >>>>>> https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc6/source/drivers/usb/gadget/function/f_uac2.c*L47__;Iw!!A4F2R9G_pg!LBySrM_zgMGV0x-zZ7nSrs54yJw1GlnpUVUVxdQE8PeszSMZ6OkFX8lSoigwRbWQzLcU$ >>>>>> >>>>>> https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc6/source/drivers/usb/gadget/function/f_uac2.c*L830__;Iw!!A4F2R9G_pg!LBySrM_zgMGV0x-zZ7nSrs54yJw1GlnpUVUVxdQE8PeszSMZ6OkFX8lSoigwRfP5TdZC$ >>>>>> >>>>>> https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc6/source/include/uapi/linux/usb/ch9.h*L453__;Iw!!A4F2R9G_pg!LBySrM_zgMGV0x-zZ7nSrs54yJw1GlnpUVUVxdQE8PeszSMZ6OkFX8lSoigwRejzMbWO$ >>>>>> >>>>>> Does that fix the problem? >>>>> >>>>> Not sure how to do that. Do you mean the module should have a parameter >>>>> called c_sync? `modinfo` list no parameters for usb_f_uac2. >>>> >>>> Those are configfs params, not available in modinfo. >>>> >>>> I checked and the value is "adaptive" >>>> https://urldefense.com/v3/__https://elixir.bootlin.com/linux/v5.14-rc7/source/drivers/usb/gadget/function/f_uac2.c*L1312__;Iw!!A4F2R9G_pg!LBySrM_zgMGV0x-zZ7nSrs54yJw1GlnpUVUVxdQE8PeszSMZ6OkFX8lSoigwRTETcbsN$ >>> >>> >>>> In your configfs script: >>> >>> Kernel shouldn't crash with any available set of configuration >>> parameters, right? So, even if the parameter would fix the crash the >>> series is buggy and has to be reverted in my opinion. >> >> Sure, no problem with reverting. I am just trying to start up some >> troubleshooting. A resource exhaustion was mentioned here, that's why I >> suggested a way to test the patch with the original number of endpoints >> allocated. I do not get any crashes on my setup which uses fewer gadget >> functions. That's why I asked what happens if the functions load order >> is changed. I am afraid this thread is so complex that the actual >> problem has been burried in the history. >> > > As I pointed out previously, the crash is probably because of f_uac2 > prematurely freeing feedback request before its completion. > usb_ep_dequeue() is asynchronous. dwc2() may treat it as a synchronous > call so you didn't get a crash.
Thanks for your hint, it greatly helps. >> > > I'm not sure how easy it is for you to obtain/test a device with dwc3, > but it would be great to also have it as part of your testing suite. :)
Can you recommend a reasonably priced device with viable kernel updates for the testing? Optionally with SS which you mentioned last time? Thanks.
Best regards,
Pavel.
| |