[PATCH 2/2] arm64: dts: rockchip: Define values for the IPA governor for rock960

From: Daniel Lezcano
Date: Tue Jun 04 2019 - 13:02:24 EST


Currently the default thermal values for the rk3399-rock960 board is
inherited from the generic definition in rk3399.dtsi.

In order to ensure the rock960 has more room for througput before
being capped by the thermal framework and is correctly supported by
the IPA governor, let's define the power values and the right trip
points for better performances:

- sustainable power is tested to be 1550mW

- increase the first mitigation point to 75ÂC in order to get better
performances

- the first trip point is 65ÂC in order to let the IPA to collect
enough data for the PID regulation when it reaches 75ÂC

- restrict the cooling device to the big CPUs as the little CPUs
contribution to the heating effect can be considered negligible

The intelligent power allocator PID coefficient to be set in sysfs
are:

k_d: 0
k_po: 79
k_i: 10
k_pu: 50

Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
.../boot/dts/rockchip/rk3399-rock960.dts | 39 +++++++++++++++++++
1 file changed, 39 insertions(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3399-rock960.dts b/arch/arm64/boot/dts/rockchip/rk3399-rock960.dts
index 12285c51cceb..701d5b5fad46 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-rock960.dts
+++ b/arch/arm64/boot/dts/rockchip/rk3399-rock960.dts
@@ -114,6 +114,45 @@
};
};

+&thermal_zones {
+ cpu_thermal: cpu {
+ polling-delay-passive = <100>;
+ polling-delay = <1000>;
+ thermal-sensors = <&tsadc 0>;
+ sustainable-power = <1550>;
+
+ trips {
+ cpu_alert0: cpu_alert0 {
+ temperature = <65000>;
+ hysteresis = <2000>;
+ type = "passive";
+ };
+
+ cpu_alert1: cpu_alert1 {
+ temperature = <75000>;
+ hysteresis = <2000>;
+ type = "passive";
+ };
+
+ cpu_crit: cpu_crit {
+ temperature = <95000>;
+ hysteresis = <2000>;
+ type = "critical";
+ };
+ };
+
+ cooling-maps {
+ map0 {
+
+ trip = <&cpu_alert1>;
+ cooling-device =
+ <&cpu_b0 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>,
+ <&cpu_b1 THERMAL_NO_LIMIT THERMAL_NO_LIMIT>;
+ };
+ };
+ };
+};
+
&usbdrd_dwc3_0 {
dr_mode = "otg";
};
--
2.17.1