On 2014/11/30 6:30, Rafael J. Wysocki wrote: > On Saturday, November 29, 2014 09:40:02 AM Wang Weidong wrote: >> On 2014/11/29 9:26, Rafael J. Wysocki wrote: >>> On Friday, November 28, 2014 10:43:37 AM Wang Weidong wrote: >>>> Hi Rafael and Viresh >>>> >>>> Sorry to trouble you again. As for: >>>> "acpi-cpufreq: get the cur_freq from acpi_processor_performance states" >>>> I do it again, and add the other patch. >>>> >>>> patch #1: acpi-cpufreq: make the freq_table store the same freq value >>>> >>>> I think it can work. The set of available states which come >>>> from acpi won't change. Just like the power would be remove, >>>> the acpi driver will do that: >>>> call >>>> ->acpi_processor_ppc_has_changed >>>> ->cpufreq_update_policy >>>> ->acpi_ppc_notifier_block.notifier_call >>>> ->acpi_processor_ppc_notifier >>>> ->cpufreq_verify_within_limits >>>> The progress will change the policy's min_freq and max_freq >>>> while it won't change the set of states(freq_tables). >>> >>> OK, so the above information needs to go into the changelog of patch [1/2]. >>> Also, please clarify the problem description in that changelog, it is very >>> difficult to understand the way it is now. >>> >> >> sure, I should do it. >> >>>> patch #2: cpufreq: show the real avail freqs with the freq_table >>>> >>>> when the min_freq and max_freq change, we should sync the availble >>>> freqs. >>> >>> Why? Do any other cpufreq drivers do that? >>> >> >> If some cpufreq drivers support several freqs like this: >> 1.05 Ghz 1.30Ghz 1.70GHz 2.10GHz 2.3GHz >> | | >> min max >> So what the available freqs is 1.30GHz 1.70GHz 2.10GHz >> >> when we do cpufreq-info or cat scaling_available_frequencies, >> I think the available freqs table show only show these 3 value, >> not all the values. > > That changes an existing user space interface, however, and the > only reason I can figure out from what you're saying is your personal > opinion. This isn't a good enough reason, however. > > What if there are utilities and scripts out there relying on the > current behavior? >
No, there are not utilities and scripts relying on it. I just confuse that: If the policy->min and policy-max is changed while it shows all available freqs though scaling_available_frequencies. I can't set all freq-steps, only [policy->min, policy->max]. why should it show all the available freqs. Although, it doesn't impact on us. So just ignore the patch#2. :) Wang, Regards > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
