[PATCH v2 0/6] Switch to generic syscon regmap based drivers

[Alim Akhtar]

On 10/21/2015 04:12 PM, Markus Reichl wrote:
> Am 21.10.2015 um 12:16 schrieb Javier Martinez Canillas:
>> Hello Alim,
>>
>> On 10/21/2015 08:09 AM, Alim Akhtar wrote:
>>
>> [snip]
>>
>>>>>>>
>>>>>>> Hi Alim,
>>>>>>>
>>>>>>> I have installed your patch set above with git am on top of
>>>>>>> 4.3.0-rc6-00108-gce1fad2 torvalds/linux of today
>>>>>>> with make exynos_defconfig on Odroid U3.
>>>>>>>
>>>>>> which exynos soc Odroid U3 uses?
>>>>>>
>>>>> OK, I can see its uses exynos4412 and exynos4412-odroidu3.dts does
>>>>> include exynos4.dtsi,
>>>>> so these should have worked.
>>>>>
>>>>>>> "halt -p" worked (power 0.0W).
>>>>>>> "reboot" got stuck at 0.5W.
>>>>>>>
>>>>>> reboot stuck mean system does not reboot any more?
>>>>
>>>> It freezes when going for reboot.
>>>> Have to power off/on to boot again.
>>>>
>>>> Btw I use an mmc, not an sd-card.
>>>> No other HW connected, just LAN-cable.
>>>> Bootloader is u-boot v2015.10.
>>>> o
>>> Have checked on 4.3.0-rc6-00006-gd03c139e7e77, still works on peach boards.
>>> Sorry I don't have Odroid U3 with me, may be Javier or Krzysztof might help here to check whats wrong. To me its looks more of a board specific issue for now.
>>>
>>
>> Krzysztof has an Odroid XU3 lite and I have an Odroid XU4, both uses an
>> Exynos5422 so we can't check what's wrong with Odroid U3 (Exynos4412).
>>
>> Having said that I think I know what is the issue here. Markus said that
>> he is using an eMMC instead of an uSD (which is what I used and my guess
>> is that Krzysztof did too).
>>
>> Now, there is a subtle difference between the old PMU restart handler
>> and the syscon-reboot one, and that is the restart handler priorities:
>>
>> notifier                    priority
>> ------------------------------------
>> pmu_restart_notify          128
>> mmc_pwrseq_emmc_reset_nb    129
>> syscon_restart_handle       192
>>
>> So, without Alim's patches, first the eMMC reset handler will be called
>> and then the PMU restart handler but after his series, the syscon reset
>> handler has a higher priority so the eMMC reset will never be called.
>>
>> But the problem is that the eMMC card has to be properly reset on system
>> restart to allow the SoC iROM to be able to read the bootloader from the
>> eMMC since the iROM doesn't have restart logic and the card shouldn't be
>> left in an unknown state.
>>
>> So the problem here is not that the system is not being reset (that I
>> think that works) but that on reboot, the system is not able to boot
>> again since the ROM is not able to read the second stage bootloader.
>>
>> Markus,
>>
>> Can you please test following patch [0] on top of Alim's series? If that
>> works then it should either be part of Alim's series or the patches will
>> have to wait until that patch lands into mainline. I don't have an eMMC
>> to test it in XU4 but I'm pretty confident that it will solve the issue.
>
> Hi Javier,
>
> your patch fixes the issue, reboot works now on U3.
>
Good to know that.
Thanks
> Tested-by: Markus Reichl <m.reichl at fivetechno.de>
>
> Thanks,
> --
> Markus
>
>
>>
>> Best regards,
>>
>
>
>