[PATCH RFC 1/2] clk: introduce clk_invalidate_rate()

Neil Armstrong narmstrong at baylibre.com
Thu Sep 26 23:40:42 PDT 2019


On 27/09/2019 02:14, Stephen Boyd wrote:
> Quoting Neil Armstrong (2019-09-19 03:25:17)
>> This introduces the clk_invalidate_rate() call used to recalculate the
>> rate and parent tree of a particular clock if it's known that the
>> underlying registers set has been altered by the firmware, like from
>> a suspend/resume handler running in trusted cpu mode.
>>
>> The call refreshes the actual parent and when changed, instructs CCF
>> the parent has changed. Finally the call will recalculate the rate of
>> each part of the tree to make sure the CCF cached tree is in sync with
>> the hardware.
>>
>> Signed-off-by: Neil Armstrong <narmstrong at baylibre.com>
>> ---
> 
> The knee-jerk reaction to these patches is that it shouldn't be a
> consumer API (i.e. taking a struct clk) but a provider API (i.e. taking
> a struct clk_hw). I haven't looked in any more detail but just know that
> it's a non-starter to be a consumer based API because we don't want
> random consumers out there to be telling the CCF or provider drivers
> that some clk has lost state and needs to be "refreshed".
> 

Totally agree, I hesitated and obviously did the wrong choice, but
this is a nit, the main algorithm is not tied to the API level.

Should I resend it with clk_hw ? the difference will be small and
the main subject is the resync algorithm.

Neil



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