On 2/11/2016 4:32 PM, Michael Turquette wrote: > Quoting Rhyland Klein (2016-02-10 10:34:16) >> On 2/9/2016 9:56 PM, Emilio López wrote: >>> Hi, >>> >>> El 09/02/16 a las 19:48, Rhyland Klein escribió: >>>> When clocks are registered, they could be enabled already in >>>> hardware. As of now, the enable count will start at 0. When this >>>> happens, it means a clock is enabled and the framework doesn't know >>>> that, so it will always report it as disabled. ... > > clk_disable_unused() handles the case where spurious clocks were left > enabled by the bootloader and need to be gated. This sounds like the > only thing you were after. > > We also have a case where clocks are gated by clk_disable_unused() > because no driver has claimed them yet, but we really want those clocks > to be left enabled. For example, clocks supplying DDR & CPU shouldn't be > cut, ever. Alternatively, your bootloader put something on the display > but your display controller module hasn't loaded yet. Cutting the clock > isn't fatal but causes unnecessary screen flicker because the module has > not loaded up. > > To solve those sets of problems there is the critical clocks and handoff > clocks thread[0]. > > [0] > http://lkml.kernel.org/r/<[email protected]> > > Best regards, > Mike >
Thanks. I agree the clk_disable_unused should clear up the situation I was in. And the critical clocks and handoff logic should be useful. I am sure we can make use of it once its in for Tegra support. -rhyland -- nvpublic
