Dietmar Eggemann 4daa001a17 arm64: dts: juno: Add cpu dynamic-power-coefficient information ... A CPUfreq driver, like the scpi driver used on Juno boards, which provide the Energy Model with power cost information via the PM_OPP of_dev_pm_opp_get_cpu_power() function, do need the dynamic-power-coefficient (C) in the device tree. Method used to obtain the C value: C is computed by measuring energy (E) consumption of a frequency domain (FD) over a 10s runtime (t) sysbench workload running at each Operating Performance Point (OPP) affine to 1 or 2 CPUs of that FD while the other CPUs of the system are hotplugged out. By definition all CPUs of a FD have the the same micro-architecture. An OPP is characterized by a certain frequency (f) and voltage (V) value. The corresponding power values (P) are calculated by dividing the delta of the E values between the runs with 2 and 1 CPUs by t. With n data tuples (P, f, V), n equal to number of OPPs for this frequency domain, we can solve C by: P = Pstat + Pdyn P = Pstat + CV²f Cx = (Px - P1)/(Vx²fx - V1²f1) with x = {2, ..., n} The C value is the arithmetic mean out of {C2, ..., Cn}. Since DVFS is broken on Juno r1, no dynamic-power-coefficient information has been added to its dts file. Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>		2019-01-29 15:31:37 +00:00
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dts	arm64: dts: juno: Add cpu dynamic-power-coefficient information	2019-01-29 15:31:37 +00:00
.gitignore
install.sh	arm64: kbuild: make "make install" not depend on vmlinux	2016-02-19 10:33:35 +00:00
Makefile	arm64: localise Image objcopy flags	2016-07-19 15:30:23 +01:00