Hi,

> Am 09.09.2020 um 21:56 schrieb H. Nikolaus Schaller <[email protected]>:
> 
> Hi Robert,
> 
>> Am 09.09.2020 um 17:22 schrieb H. Nikolaus Schaller <[email protected]>:
>> 
>> 
>>> Am 09.09.2020 um 17:15 schrieb Robert Nelson <[email protected]>:
>>> 
>>>> Ah, ok. I'll look into that.
>>>> 
>>>> But does it mean it is not a kernel problem? Is there no kernel-only 
>>>> solution (without touching u-boot)?
>>>> I do not need the RTC or RTC wakeup, just safe power-down by 
>>>> user-command...
>>> 
>>> RTC "sub-system" is used for Power Off on am335x, from what i've read,
>>> that RTC register can only be set in u-boot (aka very early)..
>> 
>> Ok, I'll dig into that code and direction...
> 
> I have checked your patch and I have found that my U-Boot already includes 
> rtc32k_enable().
> It is compiled into SPL/MLO and seems to work because depending on
> 
>       writel((0 << 3) | (1 << 6), &rtc->osc);
> 
> or
> 
>       writel((1 << 3) | (1 << 6), &rtc->osc);
> 
> I can read different values from Linux:
> 
> root@letux:~# devmem2 0x44E3E054
> /dev/mem opened.
> Memory mapped at address 0xb6fba000.
> Value at address 0x44E3E054 (0xb6fba054): 0x40
> root@letux:~# 
> 
> or
> 
> root@letux:~# devmem2 0x44E3E054
> /dev/mem opened.
> Memory mapped at address 0xb6f77000.
> Value at address 0x44E3E054 (0xb6f77054): 0x48
> root@letux:~# 
> 
> But it has no influence on the "poweroff" behaviour. In either case reboot 
> does not
> shut down the PMIC like pressing the power button 10 seconds.

Maybe I had done something wrong with installing the new MLO and testing.
But now "poweroff" in kernel works with writel((0 << 3) | (1 << 6), &rtc->osc);
in U-Boot.

> 
> Did I miss something what your patch is doing in addition to handle the 
> osd3358?
> 
> I didn't mention, but
> * "reboot" works
> * rtcwake -m mem -s 10 fails to wake up (sleeps and there is no activity LED 
> flickering like with poweroff)
> * 32kHz XTAL is working and active (even during suspend and in the strange 
> poweroff state)
> * oscillator is off after forced poweroff (there is no backup battery 
> connected)
> 
> Suspend seems to be a deeper sleep state than power off?
> 
> Interestingly, hwclock -r stalls for 10 seconds, reports 00:00:57 (or similar 
> after cold boot)
> and does not increment. I can write the hwclock but it still does not 
> increment.
> 
> So for some reason the RTC isn't running but can be accessed.

This seems to be a separate issue.

BR and thanks,
Nikolaus

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