From a06d4fdec1ce800188bec15c0219d6774dd145f8 Mon Sep 17 00:00:00 2001 From: Dmitry Rokosov Date: Sat, 10 Feb 2024 00:28:06 +0300 Subject: [PATCH] arm64: dts: amlogic: axg: initialize default SoC capacitance The capacitance value is required for the usage of the cpufreq cooling device and power_allocator thermal governor in the appropriate energy model. It helps to compute the power estimated by the SoC at the appropriate frequency. If it is the frequency of an existing OPP, or at the frequency of the first OPP above the requested value otherwise. The power is estimated as P = C * V^2 * f, with C being the SoC's capacitance and V and f respectively representing the voltage and frequency of the OPP. Since AXG SoC doesn't have SCMI protocol support, we need to initialize capacitance using the 'dynamic-power-coefficient' DT entry. Its value is retrieved from the vendor kernel, and it gives us the following freq2power mapping: +-----------+--------+ | frequency,| power, | | MHz | uW | +-----------+--------+ | 100 | 10354 | +-----------+--------+ | 250 | 27104 | +-----------+--------+ | 500 | 55447 | +-----------+--------+ | 667 | 77327 | +-----------+--------+ | 1000 | 129024 | +-----------+--------+ | 1200 | 164656 | +-----------+--------+ | 1296 | 192489 | +-----------+--------+ | 1416 | 239870 | +-----------+--------+ Signed-off-by: Dmitry Rokosov Reviewed-by: Neil Armstrong Link: https://lore.kernel.org/r/20240209212816.11187-3-ddrokosov@salutedevices.com Signed-off-by: Neil Armstrong --- arch/arm64/boot/dts/amlogic/meson-axg.dtsi | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi index ea96fef328e89..6d12b760b90f7 100644 --- a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi +++ b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi @@ -74,6 +74,7 @@ enable-method = "psci"; next-level-cache = <&l2>; clocks = <&scpi_dvfs 0>; + dynamic-power-coefficient = <140>; #cooling-cells = <2>; }; @@ -84,6 +85,7 @@ enable-method = "psci"; next-level-cache = <&l2>; clocks = <&scpi_dvfs 0>; + dynamic-power-coefficient = <140>; #cooling-cells = <2>; }; @@ -94,6 +96,7 @@ enable-method = "psci"; next-level-cache = <&l2>; clocks = <&scpi_dvfs 0>; + dynamic-power-coefficient = <140>; #cooling-cells = <2>; }; @@ -104,6 +107,7 @@ enable-method = "psci"; next-level-cache = <&l2>; clocks = <&scpi_dvfs 0>; + dynamic-power-coefficient = <140>; #cooling-cells = <2>; }; -- 2.30.2