Fastboot

[Jonas Vautherin]

Thanks a lot Sean!

I tried to enable logging by using the following CONFIG_:

```
CONFIG_LOG=y
CONFIG_SPL_LOG=y
CONFIG_TPL_LOG=y
CONFIG_LOG_MAX_LEVEL=5
CONFIG_SPL_LOG_MAX_LEVEL=3
CONFIG_TPL_LOG_MAX_LEVEL=3
CONFIG_LOG_DEFAULT_LEVEL=7
CONFIG_LOG_CONSOLE=y
CONFIG_SPL_LOG_CONSOLE=y
CONFIG_TPL_LOG_CONSOLE=y

CONFIG_CMD_LOG=y
```

And I got the "log" function indeed. But it did not have the effect I was
hoping for:

```
=> log level set 7
=> log level
Default log level: 0
=> usb start
starting USB...
Bus usb at 47401800: Port not available.
```

First, I don't get why it says "Default log level: 0" after I set it (to
whatever number, apparently). And second, it does not seem to bring me more
output about the usb issue :-/.

Am I missing something?

Best,
Jonas

On Sat, Mar 6, 2021 at 3:20 AM Sean Anderson <seanga2 at gmail.com> wrote:

> On 3/5/21 7:10 PM, Jonas Vautherin wrote:
> > Hello!
> >
> > I am learning about Fastboot, and I would like to run it from u-boot and
> > detect it from my host computer (I have the tools on my host, that's
> > working with other devices).
> >
> > I am using a pocketbeagle and I built an image using Yocto. I can get
> into
> > the u-boot prompt at boot time, and I get the following output:
> >
> > ```
> > Rebooting... reboot: Restarting system
> >
> > U-Boot SPL 2020.07 (Jul 06 2020 - 19:22:53 +0000)
> > Trying to boot from MMC1
> >
> >
> > U-Boot 2020.07 (Jul 06 2020 - 19:22:53 +0000)
> >
> > CPU  : AM335X-GP rev 2.1
> > Model: TI AM335x PocketBeagle
> > DRAM:  512 MiB
> > WDT:   Started with servicing (60s timeout)
> > NAND:  0 MiB
> > MMC:   OMAP SD/MMC: 0
> > Loading Environment from FAT... *** Warning - bad CRC, using default
> > environment
> >
> > <ethaddr> not set. Validating first E-fuse MAC
> > Net:   No ethernet found.
> > Hit any key to stop autoboot:  2
> > ```
> >
> > If I hit a key here, I get the u-boot prompt (`=>`) where I find
> > "fastboot". The thing is that none of the fastboot commands I run have
> any
> > output:
>
> This is normal. There will be output only when you issue commands.
>
> >
> > * fastboot usb 0
> > * fastboot usb
> > * fastboot udp
> >
> > Now, fastboot udp is not enabled in my defconfig, but the udp gadget
> > support is, and the usb fastboot gadget is enabled, too. From my host, I
> > just don't see anything in the `dmesg` output.
> >
> > Here are a few questions:
> >
> > * Does fastboot usb go over ethernet? If yes, I guess that the "Net: No
> > ethernet found." message is an issue that I need to fix such that a new
> usb
> > network interface is created by my host, but from my tests with this
> > proprietary device I own, it does not seem to be enumerated as a network
> > interface.
>
> Only udp goes over ethernet (though I suppose you could use a
> usb-ethernet gadget/dongle).
>
> > * In readthedocs [1], it mentions that "The CONFIG_USB_GADGET_VENDOR_NUM
> > must be one of the numbers supported by the fastboot client." In my
> setup,
> > it is set to 0x0451, and I did not find what is supposed to be supported
> in
> > fastboot.cpp [2]. So from the host, I also tried `fastboot -i 0x0451
> > devices`. Is that an issue?
>
> The fastboot client detects devices with two bulk endpoints and the
> correct interface (see match_fastboot and filter_usb_device). Generally,
> you will only have to specify the vid/pid/serial if you have multiple
> devices plugged in at once.
>
> > * I thought that maybe I should start USB, because the output of `usb
> tree`
> > says "USB is stopped. Please issue 'usb start' first.". But running `usb
> > start` errors with "Bus usb at 47401800: Port not available.". Is that
> related
> > to fastboot at all, i.e. should I be concerned about that? And how can I
> > debug it?
>
> That's probably why your fastboot isn't working :)
>
> You can try debugging it by enabling debug messages. If you want less than
> a firehose, you can try setting the default log level to info, and then
> setting it to debug before running usb start. See [1] for details.
>
> [1] https://u-boot.readthedocs.io/en/latest/develop/logging.html
>
> --Sean
>
> > Thanks in advance for the help!
> > Jonas
> >
> > [1]: https://u-boot.readthedocs.io/en/latest/android/fastboot.html
> > [2]:
> >
> https://android.googlesource.com/platform/system/core/+/master/fastboot/fastboot.cpp
> >
>
>