? 2016/8/23 17:03, Heiko St?bner ??: > Hi Finley, > > Am Dienstag, 23. August 2016, 12:10:27 schrieb Finley Xiao: >> ? 2016/8/19 21:36, Rob Herring ??: >>> On Tue, Aug 16, 2016 at 10:38:59AM +0800, Finlye Xiao wrote: >>>> From: Finley Xiao <finley.xiao at rock-chips.com> >>>> >>>> This patch supports adjusting opp's voltage according to leakage >>>> >>>> Signed-off-by: Finley Xiao <finley.xiao at rock-chips.com> >>>> --- >>>> >>>> .../devicetree/bindings/power/rockchip-cpu-avs.txt | 37 +++ >>>> drivers/power/avs/Kconfig | 8 + >>>> drivers/power/avs/Makefile | 1 + >>>> drivers/power/avs/rockchip-cpu-avs.c | 314 >>>> +++++++++++++++++++++ 4 files changed, 360 insertions(+) >>>> create mode 100644 >>>> Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt create >>>> mode 100644 drivers/power/avs/rockchip-cpu-avs.c >>>> >>>> diff --git a/Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt >>>> b/Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt new file >>>> mode 100644 >>>> index 0000000..90f6b08 >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/power/rockchip-cpu-avs.txt >>>> @@ -0,0 +1,37 @@ >>>> +Rockchip cpu avs device tree bindings >>>> +------------------------------------- >>>> + >>>> +Under the same frequency, the operating voltage tends to decrease with >>>> +increasing leakage. so it is necessary to adjust opp's voltage according >>>> +to leakage for power. >>>> + >>>> + >>>> +Required properties: >>>> +- compatible: Should be one of the following. >>>> + - "rockchip,rk3399-cpu-avs" - for RK3399 SoCs. >>>> +- leakage-volt-<name>: Named leakage-volt property. At runtime, the >>>> + platform can find a cpu's cluster_id according to it's cpu_id and >>>> match >>>> + leakage-volt-<name> property. The property is an array of 3-tuples >>>> + items, and each item consists of leakage and voltage like >>>> + <min-leakage-mA max-leakage-mA vol-uV>. >>>> + min-leakage: minimum leakage in mA. >>>> + max-leakage: maximum leakage in mA. >>>> + vol: voltage in microvolt. >>> How do you determine these values? When do they vary? >> How do you determine these values? >> >> run antutu-benchmark >> leakage freq min_volt >> 30mA 1608MHz 1025mV >> 40mA 1608MHz 1000mV >> 50mA 1608MHz 975mV >> >> From the table, we see the min_volt decrease with increasing leakage. >> So we can set the default opp-microvolt 1025mV for 1608MHz, >> and add an leakage_volt_cluster0 property as follows. >> leakage_volt_cluster0 = < >> /* min(mA) max(mA) volt(uV)*/ >> 0 40 0 >> 41 50 (-25000) >> 51 254 (-50000) >> >>> ; >> If the leakage is between 41mA and 50mA?the opp-microvolt will subtract >> 25mV? If the leakage is between 41mA and 50mA?the opp-microvolt will >> subtract 50mV? >> >> When do they vary? >> >> From the code, >> cpufreq_online >> --cpufreq_driver->init(policy); /* add new opp table */ >> --blocking_notifier_call_chain(&cpufreq_policy_notifier_list, >> CPUFREQ_START, policy); >> --cpufreq_init_policy >> ----cpufreq_set_policy >> --------__cpufreq_governor(policy, CPUFREQ_GOV_START); >> >> The cpu's opp table is added in the init function(cpufreq_init)?and I will >> register a cpufreq notifier, once the first cpu of cluster is onlined, >> my notifer will be called, and if the event is CPUFREQ_START?it will modify >> the opp-microvolt according to leakage_volt_cluster0. > I think what Rob was asking with "when do they vary" is, are these leakage > values the same for each and every rk3399 soc or are they determined > separately for each board-type using the rk3399. Oh, sorry, I misunderstood. They are the same for every rk3399 soc. > > > > > -- Finley
