netconsole over USB net not working

[Andy Shevchenko]

On Wed, Nov 10, 2021 at 9:47 PM Andy Shevchenko
<andy.shevchenko at gmail.com> wrote:
>
> Hi!
>
> What is the Best Known Method to enable NetConsole over USB ethernet
> gadget on DWC3?

Any insight anyone? v2022.01-rc2 behaves the same way.
It was checked that in USB host mode and external card the netconsole
setup works.

> Currently I have a "blinking" type of network interface (from the host
> side) and it's too hard to understand all the mysterious ways of this
> setup.
>
> I have set std* to "nc,serial" (*) to be able to have the network
> console be set up and running.
>
> *) "serial" is just for the initial boot strap, this is a product
> ready Android tablet that users are not supposed to solder wires on
> its PCB. No need to say that I have another similar device
> (https://lore.kernel.org/u-boot/CAHp75VdPTU-THtHi3eRiD7rd_tC90fC66AiUvzMnoF2Ky0J_HQ@mail.gmail.com/T/#u)
> that has no serial interface at all, and I can't do anything about it
> due to lack of support from U-Boot.
>
> Unfortunately it goes this direction (in net_loop() call)
>        net_init();
>        if (eth_is_on_demand_init()) {
>                eth_halt();
>                eth_set_current();
>                ret = eth_init();
>                if (ret < 0) {
>                        eth_halt();
>                        return ret;
>                }
>
> The problem here is that the gadget timeouts for some reason and of
> course for the default 3 seconds I may not have enough time to set up
> the network on the host side. Moreover, if by luck I manage to achieve
> that, it still doesn't work.
>
> --- net_loop Entry
> Trying usb_ether
> 0
>   - 0 'dwc3'
>   - found
> using dwc3-gadget, OUT ep2out IN ep2in STATUS ep3in
> MAC de:ad:be:ef:00:01
> HOST MAC de:ad:be:ef:00:00
> ...
> dwc3-generic-peripheral dwc3: Transfer Not Ready while ep0out in state
> 'Data Phase'dwc3-generic-peripheral dwc3:
> Transfer Complete while ep0out in state 'Status Phase'The remote end
> did not respond in time.eth_reset_config
> dwc3-generic-peripheral dwc3: request 36561380 from ep3in completed
> 0/8 ===> -108
> event 00 --> -108
> eth_unbind...
> FAIL
>
> ...and repeat...
>
> Conclusion it is not working at all.
>
> Expectations:
> the USB gadget leaves UDC in state that the host would be able to set
> up the link and the netconsole would be able to send data to it.
>
> How to achieve that?
>
> Alternative: serial function of the composite device. As of today not
> an option — it simply does not exist in the U-Boot. Anybody is working
> on that?
>
> --
> With Best Regards,
> Andy Shevchenko



-- 
With Best Regards,
Andy Shevchenko