[PATCH 1/3] arm64: dts: rockchip: Update CPU OPP voltages in RK356x SoC dtsi

From: Dragan Simic
Date: Sat Oct 12 2024 - 13:05:02 EST


Update the lower/upper voltage limits and the exact voltages for the Rockchip
RK356x CPU OPPs, using the most conservative values (i.e. the highest per-OPP
voltages) found in the vendor kernel source. [1]

Using the most conservative per-OPP voltages ensures reliable CPU operation
regardless of the actual CPU binning, with the downside of possibly using
a bit more power for the CPU cores than absolutely needed.

Additionally, fill in the missing "clock-latency-ns" CPU OPP properties, using
the values found in the vendor kernel source. [1]

[1] https://raw.githubusercontent.com/rockchip-linux/kernel/f8b9431ee38ed561650be7092ab93f564598daa9/arch/arm64/boot/dts/rockchip/rk3568.dtsi

Related-to: eb665b1c06bc ("arm64: dts: rockchip: Update GPU OPP voltages in RK356x SoC dtsi")
Signed-off-by: Dragan Simic <dsimic@xxxxxxxxxxx>
---
arch/arm64/boot/dts/rockchip/rk3568.dtsi | 1 +
arch/arm64/boot/dts/rockchip/rk356x.dtsi | 18 ++++++++++++------
2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/arch/arm64/boot/dts/rockchip/rk3568.dtsi b/arch/arm64/boot/dts/rockchip/rk3568.dtsi
index 0946310e8c12..5c54898f6ed1 100644
--- a/arch/arm64/boot/dts/rockchip/rk3568.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3568.dtsi
@@ -273,6 +273,7 @@ &cpu0_opp_table {
opp-1992000000 {
opp-hz = /bits/ 64 <1992000000>;
opp-microvolt = <1150000 1150000 1150000>;
+ clock-latency-ns = <40000>;
};
};

diff --git a/arch/arm64/boot/dts/rockchip/rk356x.dtsi b/arch/arm64/boot/dts/rockchip/rk356x.dtsi
index 0ee0ada6f0ab..534593f2ed0b 100644
--- a/arch/arm64/boot/dts/rockchip/rk356x.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk356x.dtsi
@@ -134,39 +134,45 @@ cpu0_opp_table: opp-table-0 {

opp-408000000 {
opp-hz = /bits/ 64 <408000000>;
- opp-microvolt = <900000 900000 1150000>;
+ opp-microvolt = <850000 850000 1150000>;
clock-latency-ns = <40000>;
};

opp-600000000 {
opp-hz = /bits/ 64 <600000000>;
- opp-microvolt = <900000 900000 1150000>;
+ opp-microvolt = <850000 850000 1150000>;
+ clock-latency-ns = <40000>;
};

opp-816000000 {
opp-hz = /bits/ 64 <816000000>;
- opp-microvolt = <900000 900000 1150000>;
+ opp-microvolt = <850000 850000 1150000>;
+ clock-latency-ns = <40000>;
opp-suspend;
};

opp-1104000000 {
opp-hz = /bits/ 64 <1104000000>;
opp-microvolt = <900000 900000 1150000>;
+ clock-latency-ns = <40000>;
};

opp-1416000000 {
opp-hz = /bits/ 64 <1416000000>;
- opp-microvolt = <900000 900000 1150000>;
+ opp-microvolt = <1025000 1025000 1150000>;
+ clock-latency-ns = <40000>;
};

opp-1608000000 {
opp-hz = /bits/ 64 <1608000000>;
- opp-microvolt = <975000 975000 1150000>;
+ opp-microvolt = <1100000 1100000 1150000>;
+ clock-latency-ns = <40000>;
};

opp-1800000000 {
opp-hz = /bits/ 64 <1800000000>;
- opp-microvolt = <1050000 1050000 1150000>;
+ opp-microvolt = <1150000 1150000 1150000>;
+ clock-latency-ns = <40000>;
};
};