Re: [PATCH v3 1/4] cmd: bind: Add unbind command with driver filter

[Miquel Raynal <miquel.raynal@bootlin.com>]

Hi Marek,

marex@denx.de wrote on Mon, 31 Jul 2023 16:40:04 +0200:

> On 7/31/23 16:25, Miquel Raynal wrote:
> > Hi Marek,
> > 
> > marex@denx.de wrote on Mon, 31 Jul 2023 16:08:19 +0200:
> >   
> >> On 7/31/23 15:58, Miquel Raynal wrote:  
> >>> Hi Marek,
> >>>
> >>> marex@denx.de wrote on Mon, 31 Jul 2023 15:50:58 +0200:  
> >>>    >>>> On 7/31/23 15:36, Miquel Raynal wrote:  
> >>>>> Hi Marek,
> >>>>>
> >>>>> marex@denx.de wrote on Mon, 31 Jul 2023 13:44:25 +0200:  
> >>>>>     >>>> On 7/31/23 11:31, Miquel Raynal wrote:  
> >>>>>>> Hi Marek,
> >>>>>>>
> >>>>>>> marex@denx.de wrote on Sat, 29 Jul 2023 16:57:09 +0200:  
> >>>>>>>      >>>> Extend the driver core to perform lookup by both OF node and driver  
> >>>>>>>> bound to the node. Use this to look up specific device instances to
> >>>>>>>> unbind from nodes in the unbind command. One example where this is
> >>>>>>>> needed is USB peripheral controller, which may have multiple gadget
> >>>>>>>> drivers bound to it. The unbind command has to select that specific
> >>>>>>>> gadget driver instance to unbind from the controller, not unbind the
> >>>>>>>> controller driver itself from the controller.
> >>>>>>>>
> >>>>>>>> USB ethernet gadget usage looks as follows with this change. Notice
> >>>>>>>> the extra 'usb_ether' addition in the 'unbind' command at the end.
> >>>>>>>> "
> >>>>>>>> bind /soc/usb-otg@49000000 usb_ether
> >>>>>>>> setenv ethact usb_ether
> >>>>>>>> setenv loadaddr 0xc2000000
> >>>>>>>> setenv ipaddr 10.0.0.2
> >>>>>>>> setenv serverip 10.0.0.1
> >>>>>>>> setenv netmask 255.255.255.0
> >>>>>>>> tftpboot 0xc2000000 10.0.0.1:test.file
> >>>>>>>> unbind /soc/usb-otg@49000000 usb_ether
> >>>>>>>> "
> >>>>>>>>
> >>>>>>>> Signed-off-by: Marek Vasut <marex@denx.de>
> >>>>>>>> ---  
> >>>>>>>
> >>>>>>> I am no longer getting wrong pointer dereferences, the SPL is working in
> >>>>>>> recovery mode, TFTP "File not found" errors are no longer a problem and
> >>>>>>> I did not experience any reset while tftp'ing regular files.
> >>>>>>>
> >>>>>>> One last remaining request on my side is the need for using fastboot as
> >>>>>>> well which does no longer work as-is:  
> >>>>>>>      >>> => fastboot usb 0  
> >>>>>>> couldn't find an available UDC
> >>>>>>> g_dnl_register: failed!, error: -19
> >>>>>>> exit not allowed from main input shell.
> >>>>>>>
> >>>>>>> Can you advise what bind/unbind command would be necessary here?  
> >>>>>>
> >>>>>> Either 'unbind usb_ether' or run 'dm tree' -> look up the path to usb_ether in the tree (it will be hanging under usb_peripheral or some such), and then use 'unbind <that path>'.  
> >>>>>
> >>>>> Nice `dm tree` command, never used it before.
> >>>>>
> >>>>> Even when I unbind usb_ether I still get the same error:  
> >>>>>     >>> => unbind /ocp/usb@47400000/usb@47401000  
> >>>>> => fastboot usb 0  
> >>>>> couldn't find an available UDC
> >>>>> g_dnl_register: failed!, error: -19
> >>>>> exit not allowed from main input shell.
> >>>>>
> >>>>> Is there a specific gadget driver which I should bind again manually?  
> >>>>
> >>>> Can you share the output of dm tree before/after unbind ?
> >>>>
> >>>> fastboot should auto-bind to the right thing.  
> >>>
> >>> Ok. Apparently it does not, but I don't have any clue why. If you want
> >>> me to check something else I will. Here is the output:
> >>>
> >>> U-Boot 2023.07-00806-g979e7443428 (Jul 31 2023 - 11:17:06 +0200)  
> >>
> >> [...]
> >>  
> >>>    watchdog      0  [ + ]   omap3_wdt             |   |-- wdt@44e35000
> >>>    misc          0  [ + ]   ti-musb-wrapper       |   |-- usb@47400000
> >>>    usb           0  [ + ]   ti-musb-peripheral    |   |   |-- usb@47401000
> >>>    ethernet      1  [ + ]   usb_ether             |   |   |   `-- usb_ether
> >>>    bootdev       3  [   ]   eth_bootdev           |   |   |       `-- usb_ether.bootdev
> >>>    usb           0  [   ]   ti-musb-host          |   |   `-- usb@47401800
> >>>    ethernet      0  [ + ]   eth_cpsw              |   |-- ethernet@4a100000
> >>>    bootdev       2  [   ]   eth_bootdev           |   |   `-- ethernet@4a100000.bootdev
> >>>    simple_bus   67  [   ]   ti_sysc               |   |-- target-module@53100000
> >>>    simple_bus   68  [   ]   ti_sysc               |   |-- target-module@53500000
> >>>    simple_bus   69  [   ]   ti_sysc               |   `-- target-module@56000000
> >>>    clk          62  [   ]   fixed_clock           |-- clk_mcasp0_fixed
> >>>    bootstd       0  [   ]   bootstd_drv           |-- bootstd
> >>>    bootmeth      0  [   ]   bootmeth_efi          |   |-- efi
> >>>    bootmeth      1  [   ]   bootmeth_extlinux     |   |-- extlinux
> >>>    bootmeth      2  [   ]   bootmeth_pxe          |   |-- pxe
> >>>    bootmeth      3  [   ]   vbe_simple            |   `-- vbe_simple
> >>>    timer         0  [ + ]   omap_timer            `-- timer@0  
> >>> => unbind /ocp/usb@47400000/usb@47401000  
> >>
> >> The commit message of this patch contains the following example:
> >> unbind /soc/usb-otg@49000000 usb_ether
> >> so in your case, try
> >> unbind /ocp/usb@47400000/usb@47401000 usb_ether  
> > 
> > Does not work, unfortunately:  
> > => unbind /ocp/usb@47400000/usb@47401000 usb_ether  
> > Cannot find a device with path /ocp/usb@47400000/usb@47401000  
> > => unbind /ocp/usb@47400000/usb@47401000  
> 
> Did this even work before , i.e. without this series, if you were to use USB ethernet first and then fastboot second (that sequence is important) ?

Yes it did.

> Can you debug this ? Basically the problem that happens is that if you run:
> unbind /ocp/usb@47400000/usb@47401000
> this unbind ti-musb-peripheral usb@47401000 instead of just unbinding
> usb_ether usb_ether

True.

> Maybe just try
> unbind usb_ether

=> unbind usb_ether
unbind - Unbind a device from a driver

Usage:
unbind <node path> [<driver>]
unbind <class> <index>
unbind <class> <index> <driver>

> or
> unbind usb_ether usb_ether

=> unbind usb_ether usb_ether                   
usb_ether is not a valid uclass

> ti-musb-peripheral usb@47401000 has to stay in the dm tree output after the unbind. Or maybe try
> 
> bind /ocp/usb@47400000/usb@47401000 ti-musb-peripheral

Indeed when we perform the unbind, ti-musb-peripheral is removed. Yes,
binding it again like you advise makes it come back.

> and then the fastboot thing

Unfortunately after binding it again, so with the following dm tree
snippet:

 misc          0  [ + ]   ti-musb-wrapper       |   |-- usb@47400000
 usb           0  [   ]   ti-musb-host          |   |   |-- usb@47401800
 usb           0  [   ]   ti-musb-peripheral    |   |   `-- usb@47401000

It still fails:

=> fastboot usb 0
couldn't find an available UDC
g_dnl_register: failed!, error: -19
exit not allowed from main input shell.

Without this series, this works:
=> unbind /ocp/usb@47400000/usb@47401000
=> bind /ocp/usb@47400000/usb@47401000 ti-musb-peripheral
=> fastboot usb 0

Thanks,
Miquèl