On Wed, Feb 8, 2017 at 11:10 PM, Al Stone <ahs3@xxxxxxxxxx> wrote: > On 01/03/2017 11:37 AM, Al Stone wrote: >> On 12/14/2016 06:06 PM, Prashanth Prakash wrote: >>> This patch-set adds few additional sysfs entries to expose the >>> performance capabilities of each CPU. The performance capabilities >>> include highest perf, lowest perf, nominal perf and lowest >>> non-linear perf. See 8.4.7.1 for ACPI 6.1 spec for details on >>> these capabilities. >>> >>> cppc_cpufreq driver operates in KHz scale whereas the delivered >>> performance computed in userspace will be in abstract CPPC scale, so >>> exposing perf capabilities should allow userspace to figure out the >>> conversion factor from CPPC scale to KHz. >>> >>> Prashanth Prakash (2): >>> ACPI / CPPC: read all perf caps in a single cppc read command >>> ACPI / CPPC: add sysfs entries for CPPC perf capabilities >>> >>> drivers/acpi/cppc_acpi.c | 164 ++++++++++++++++++++++++++++++----------------- >>> include/acpi/cppc_acpi.h | 3 +- >>> 2 files changed, 107 insertions(+), 60 deletions(-) >>> >> >> Nice addition, Prashanth. I had thought about doing this, but got distracted. >> Thanks for following through :). I have not had a chance to test these yet, but >> will do so as soon as I can; my initial review is pretty positive, though. >> > > Sorry for the delays :(. These work for me, on an APM Mustang: > > # ls > feedback_ctrs lowest_non_linear_perf nominal_perf wraparound_time > highest_perf lowest_perf reference_perf > # for ii in *; do echo $ii `cat $ii`; done > feedback_ctrs ref:195829033861120 del:1261303045816320 > highest_perf 1000 > lowest_non_linear_perf 250 > lowest_perf 250 > nominal_perf 1000 > reference_perf 1000 > wraparound_time 18446744073709551615 > > > Tested-by: Al Stone <ahs3@xxxxxxxxxx> I'm not actually sure about the assumption this series is based on. I don't see anything in the spec to guarantee that it will always be safe to evaluate _CPC only once and cache its output. Thanks, Rafael -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
