Re: [PATCH 2/3] arm64: dts: rockchip: Use vctrl regulators for dynamic CPU voltages on Gru/Kevin
From: Heiko Stuebner
Date: Wed Jun 28 2017 - 11:44:38 EST
Am Freitag, 23. Juni 2017, 10:07:36 CEST schrieb Brian Norris:
> From: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
>
> The Gru device tree currently contains entries for the regulators
> ppvar_bigcpu, ppvar_litcpu, ppvar_gpu and ppvar_centerlogic; however,
> the regulators have not been made, due to the lack of binding and driver
> support for keeping the over-voltage protection (OVP) at bay and
> preventing unintended regulator shutdowns on voltage downshifts.
>
> Now, the vctrl regulator driver has been merged, along with new bindings
> for asymmetric settling time. The driver is OVP aware, it splits larger
> voltage decreases in multiple steps when necessary and adds required
> delays.
>
> This change renames each of the aforementioned regulators to
> <orig_name>_pwm and adds a new vctrl regulator named <orig_name>.
> The vctrl regulators use the voltage of their corresponding PWM regulator
> as control voltage. The OVP related values are empirical and stem from
> the Chrome OS kernel tree.
>
> Signed-off-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
Running this on Kevin resulted in gpu+centerlogic being
children of litcpu, so applied for 4.14 with the diff below.
Please holler if something looks wrong
Heiko
diff --git a/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi
index 2f1ba5ba27c8..90259cf63bb6 100644
--- a/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3399-gru.dtsi
@@ -164,7 +164,7 @@
vin-supply = <&ppvar_sys>;
};
- ppvar_bigcpu_pwm: ppvar-bigcpu_pwm {
+ ppvar_bigcpu_pwm: ppvar-bigcpu-pwm {
compatible = "pwm-regulator";
regulator-name = "ppvar_bigcpu_pwm";
@@ -195,7 +195,7 @@
ovp-threshold-percent = <16>;
};
- ppvar_litcpu_pwm: ppvar-litcpu_pwm {
+ ppvar_litcpu_pwm: ppvar-litcpu-pwm {
compatible = "pwm-regulator";
regulator-name = "ppvar_litcpu_pwm";
@@ -249,7 +249,7 @@
regulator-min-microvolt = <786384>;
regulator-max-microvolt = <1217747>;
- ctrl-supply = <&ppvar_litcpu_pwm>;
+ ctrl-supply = <&ppvar_gpu_pwm>;
ctrl-voltage-range = <786384 1217747>;
regulator-settling-time-up-us = <390>;
@@ -280,7 +280,7 @@
regulator-min-microvolt = <799434>;
regulator-max-microvolt = <1049925>;
- ctrl-supply = <&ppvar_litcpu_pwm>;
+ ctrl-supply = <&ppvar_centerlogic_pwm>;
ctrl-voltage-range = <799434 1049925>;
regulator-settling-time-up-us = <378>;