PROBLEM: DWC3 USB 3.0 not working on Odroid-XU4 with Exynos 5422

[Vivek Gautam]

On 10/17/2016 01:38 PM, Felipe Balbi wrote:
> Hi,
>
> Michael Niewöhner <linux at mniewoehner.de> writes:
>> Hi Felipe,
>> On Fri, 2016-10-07 at 22:26 +0200, Michael Niewöhner wrote:
>>> Hi Felipe,
>>>
>>> On Fr, 2016-10-07 at 10:42 +0300, Felipe Balbi wrote:
>>>> Hi,
>>>>
>>>> Michael Niewöhner <linux at mniewoehner.de> writes:
>>>>>> The clocks are same across working/non-working.
>>>>>> Is it possible to bisect the commit that's causing hang for 4.8x ?
>>>>>
>>>>> [c499ff71ff2a281366c6ec7a904c547d806cbcd1] usb: dwc3: core: re-factor init and exit paths
>>>>> This patch causes both the hang on reboot and the lsusb hang.
>>>> How to reproduce? Why don't we see this on x86 and TI boards? I'm
>>>> guessing this is failed bisection, as I can't see anything in that
>>>> commit that would cause reboot hang. Also, that code path is *NOT*
>>>> executed when you run lsusb.
>>>>
>>> I've tested this procedure multiple times to be sure:
>>>
>>> - checkout c499ff71, compile, boot the odroid
>>> - run lsusb -v => lsusb hangs, can't terminate with ctrl-c
>>> - hard reset, after boot run poweroff or reboot => board does not completely power off / reboot (see log below)
>>> - revert c499ff71, mrproper, compile, boot the odroid
>>> - run lsusb -v => shows full output, not hanging
>>> - run reboot or poweroff => board powers off / reboots just fine
>>>
>>>
>>> dmesg poweroff not working:
>>> ...
>>> [  120.733519] systemd-journald[144]: systemd-journald stopped as pid 144
>>> [  120.742663] systemd-shutdown[1]: Sending SIGKILL to remaining processes...
>>> [  120.769212] systemd-shutdown[1]: Unmounting file systems.
>>> [  120.773713] systemd-shutdown[1]: Unmounting /sys/kernel/debug.
>>> [  120.827211] systemd-shutdown[1]: Unmounting /dev/mqueue.
>>> [  121.081672] EXT4-fs (mmcblk1p2): re-mounted. Opts: (null)
>>> [  121.091687] EXT4-fs (mmcblk1p2): re-mounted. Opts: (null)
>>> [  121.095608] EXT4-fs (mmcblk1p2): re-mounted. Opts: (null)
>>> [  121.101014] systemd-shutdown[1]: All filesystems unmounted.
>>> [  121.106523] systemd-shutdown[1]: Deactivating swaps.
>>> [  121.111585] systemd-shutdown[1]: All swaps deactivated.
>>> [  121.116661] systemd-shutdown[1]: Detaching loop devices.
>>> [  121.126395] systemd-shutdown[1]: All loop devices detached.
>>> [  121.130525] systemd-shutdown[1]: Detaching DM devices.
>>> [  121.135824] systemd-shutdown[1]: All DM devices detached.
>>> [  121.166327] systemd-shutdown[1]: /lib/systemd/system-shutdown succeeded.
>>> [  121.171739] systemd-shutdown[1]: Powering off.
>>>
>>> => at this point removing the sd card would show a message
>>> "removed mmc0" (not sure what the real message was...) so the board is not completely off.
>>>
>>>
>>> dmesg poweroff working:
>>> ...
>>> [  120.733519] systemd-journald[144]: systemd-journald stopped as pid 144
>>> [  120.742663] systemd-shutdown[1]: Sending SIGKILL to remaining processes...
>>> [  120.769212] systemd-shutdown[1]: Unmounting file systems.
>>> [  120.773713] systemd-shutdown[1]: Unmounting /sys/kernel/debug.
>>> [  120.827211] systemd-shutdown[1]: Unmounting /dev/mqueue.
>>> [  121.081672] EXT4-fs (mmcblk1p2): re-mounted. Opts: (null)
>>> [  121.091687] EXT4-fs (mmcblk1p2): re-mounted. Opts: (null)
>>> [  121.095608] EXT4-fs (mmcblk1p2): re-mounted. Opts: (null)
>>> [  121.101014] systemd-shutdown[1]: All filesystems unmounted.
>>> [  121.106523] systemd-shutdown[1]: Deactivating swaps.
>>> [  121.111585] systemd-shutdown[1]: All swaps deactivated.
>>> [  121.116661] systemd-shutdown[1]: Detaching loop devices.
>>> [  121.126395] systemd-shutdown[1]: All loop devices detached.
>>> [  121.130525] systemd-shutdown[1]: Detaching DM devices.
>>> [  121.135824] systemd-shutdown[1]: All DM devices detached.
>>> [  121.166327] systemd-shutdown[1]: /lib/systemd/system-shutdown succeeded.
>>> [  121.171739] systemd-shutdown[1]: Powering off.
>>> [  121.182331] rebo�
>>>
>>>
>>>
>>> Best regards
>>> Michael Niewöhner
>>
>> I did some more tests with next-20161016. Reverting / commenting out
>> one part of your patch "solves" the lsusb hang, the reboot problem
>> and also the "debounce failed" message. [1]
>> Another "solution" is to call phy_power_off before phy_power_on. [2]
>>
>> Disclaimer: I have no idea what I was doing ;-) These were just some
>> simple trial-and-error attempts that maybe help to find the real
>> cause of the problems.
>>
>> [1]
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index 7287a76..5ef589d 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -724,6 +724,7 @@ static int dwc3_core_init(struct dwc3 *dwc)
>>   	/* Adjust Frame Length */
>>   	dwc3_frame_length_adjustment(dwc);
>>   
>> +/*
>>   	usb_phy_set_suspend(dwc->usb2_phy, 0);
>>   	usb_phy_set_suspend(dwc->usb3_phy, 0);
>>   	ret = phy_power_on(dwc->usb2_generic_phy);
>> @@ -733,6 +734,7 @@ static int dwc3_core_init(struct dwc3 *dwc)
>>   	ret = phy_power_on(dwc->usb3_generic_phy);
>>   	if (ret < 0)
>>   		goto err3;
>> +*/
>>   
>>   	ret = dwc3_event_buffers_setup(dwc);
>>   	if (ret) {
>>
>> [2]
>> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
>> index 7287a76..f6c8e13 100644
>> --- a/drivers/usb/dwc3/core.c
>> +++ b/drivers/usb/dwc3/core.c
>> @@ -726,6 +726,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
>>   
>>          usb_phy_set_suspend(dwc->usb2_phy, 0);
>>          usb_phy_set_suspend(dwc->usb3_phy, 0);
>> +       phy_power_off(dwc->usb2_generic_phy);
>> +       phy_power_off(dwc->usb3_generic_phy);
> This looks like a PHY driver bug to me. Which PHY driver are you using?
>

The exynos5-usbdrd phy driver is used for exynos platforms.
Looks like something is not right with the phy driver even
after applying the phy_calibrate patches.

Michael, are you using the last set of patches for phy calibration [1]?
[1] https://lkml.org/lkml/2015/2/2/257.


Thanks
Vivek

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