Messages in this thread | | | Date | Thu, 14 Mar 2013 11:21:32 +0200 | From | Peter De Schrijver <> | Subject | Re: [RFC 1/1] clk: Add notifier support in clk_prepare_enable/clk_disable_unprepare |
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On Thu, Mar 14, 2013 at 03:15:11AM +0100, Bill Huang wrote:
> I don't think deferring will work either, considering the usage of DVFS, > device voltage is tightly coupled with frequency, when clock rate is > about to increase, we have to boost voltage first and we can lower the > voltage after the clock rate has decreased. All the above sequence have > to be guaranteed or you might crash, so deferring not only make thing > complicated in controlling the order but also hurt performance.
But we could use notifiers in clk_prepare/clk_unprepare to set the voltage no? As clk_prepare/clk_unprepare have to be called before clk_enable or after clk_disable, the voltage can be raised to a safe level, before the clock becomes active.
Cheers,
Peter.
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