Commits
Matthias Kaehlcke committed ac60c5e33df
ARM: dts: rockchip: Add dynamic-power-coefficient for rk3288
The value was determined with the following method:
- take CPUs 1-3 offline
- for each OPP
- set cpufreq min and max freq to OPP freq
- start dhrystone benchmark
- measure CPU power consumption during 10s
- calculate Cx for OPPx
- Cx = (Px - P1) / (Vx²fx - V1²f1) [1]
using the following units: mW / Ghz / V [2]
- C = avg(C2, ..., Cn)
[1] see commit 4daa001a1773 ("arm64: dts: juno: Add cpu
dynamic-power-coefficient information")
[2] https://patchwork.kernel.org/patch/10493615/#22158551
FTR, these are the values for the different OPPs:
freq (kHz) mV Px (mW) Cx
126000 900 39
216000 900 66 370
312000 900 95 372
408000 900 122 363
600000 900 177 359
696000 950 230 363
816000 1000 297 361
1008000 1050 404 362
1200000 1100 528 362
1416000 1200 770 377
1512000 1300 984 385
1608000 1350 1156 394
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>