Re: [PATCH V5 11/18] clk: tegra210: Add support for Tegra210 clocks

From: Dmitry Osipenko
Date: Thu Jul 18 2019 - 12:34:29 EST


18.07.2019 4:15, Sowjanya Komatineni ÐÐÑÐÑ:

[snip]

>>> Please try to fix all missing dependencies and orderings.
>>
>> Peter,
>>
>> dfllCPU_OUT is the first one to go thru restore when
>> clk_restore_context traverses thru the list.
>>
>> dfllCPU_OUT has dependency on DFLL_ref and DFLL_SOC but this
>> dependency is unknown to clock-tree.
>>
>> We can add DFLL_REF and DFLL_SOC as parents to dfllCPU_OUT during
>> register so dfllCPU_OUT save/restore happens after their parents are
>> restored.
>>
>> But DFLL needs both of these to be restored before DFLLCPU_Out and as
>> DFLL_SOC restore always happens after the REF, thinking to add
>> DFLL_SOC as parent to dfllCPU_OUT so save/restore follows after their
>> dependencies.
>>
>> Please comment.
>>
> Did quick try and I see by adding dfll-soc as parent to dfllCPU_OUT, its
> in proper order after all its dependencies.
>
> Can now add dfll save/restore to do dfll reinit during restore..
>

If dfllCPU_OUT can work properly with dfll-soc being disabled, then this
kind of dependency isn't very correct and just papers over the real
problem, which is that there should be a way for CCF to specify multiple
dependencies for the clock or the reverse ordering should be used for
the restoring.