On 11/28/2012 03:05 PM, Mike Turquette wrote: > Quoting Mark Langsdorf (2012-11-28 08:18:35) >> On 11/28/2012 10:01 AM, Mike Turquette wrote: >>> Quoting Shawn Guo (2012-11-28 07:17:44) >>>> On Wed, Nov 28, 2012 at 10:58:02PM +0800, Shawn Guo wrote: >>>>> On Wed, Nov 28, 2012 at 07:16:12AM -0600, Mark Langsdorf wrote: >>>>>> I'd >>>>>> have to move most of the logic of hb_set_target() into >>>>>> clk_highbank.c:clk_pll_set_rate() and then add extra logic for when >>>>>> cpufreq is not enabled/loaded. >>>>> >>>>> You only need to move hb_voltage_change() into cpu clock's .set_rate() >>>>> hook with no need of checking if cpufreq is enabled or not. >>>>> >>>> Need to also check whether frequency or voltage should be changed first >>>> in .set_rate() though. >>>> >>>> Shawn >>>> >>> >>> The notifiers in the clk framework might be a better place for this than >>> just simply hacking the logic into the .set_rate callback. >> >> Unless the clk notifiers are different than the cpufreq notifiers, they >> don't handle returning error conditions very well. And given that the >> voltage change operation can fail (though it almost always succeeds on a >> retry) I need to be able to handle and detect that error condition. > > The notifier handler can handle the case where the transition fails (and > needs to be retried). > > Also you should check out the clk notifiers. I think they handle > failure decently. If a notifer returns an error code then everything > unrolls and the clk_set_rate operation aborts. Thanks for the pointer. The clk notifier calls seem to be working with cpufreq-cpu0. I did enough surgery on the code that I want to run a lot of stress tests before I resubmit. I'll try to have something for Tuesday. --Mark Langsdorf Calxeda, Inc. -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
