From c24a9b698fb02cd0723fa8375abab07f94b97b10 Mon Sep 17 00:00:00 2001 From: Sebastian Krzyszkowiak Date: Thu, 9 Mar 2023 21:46:01 +0100 Subject: [PATCH] arm64: dts: imx8mq-librem5: Set the DVS voltages lower They're still in the operating range according to i.MX 8M Quad datasheet. There's some headroom added over minimal values to account for voltage drop. Operational ranges (min - typ - max [selected]): - VDD_SOC (BUCK1): 0.81 - 0.9 - 0.99 [0.88] - VDD_ARM (BUCK2): 0.81 - 0.9 - 1.05 [0.84] (1000MHz) 0.90 - 1.0 - 1.05 [0.93] (1500MHz) - VDD_GPU (BUCK3): 0.81 - 0.9 - 1.05 [0.85] (800MHz) 0.90 - 1.0 - 1.05 [ -- ] (1000MHz) - VDD_VPU (BUCK4): 0.81 - 0.9 - 1.05 [ -- ] (550/500/588MHz) 0.90 - 1.0 - 1.05 [0.93] (660/600/800MHz) Idle power consumption doesn't appear to be influenced much, but a simple load test (`cat /dev/urandom | pigz - > /dev/null` combined with running Animatch) seems to show about 0.3W of difference. Care is advised, as there may be differences between each units in how low can they be undervolted - in my experience, reaching that point usually makes the phone fail to boot. In my case, it appears that my Birch phone can go down the most. This is a somewhat conservative set of values that I've seen working well on all my devices; I haven't tried very hard to optimize it, so more experiments are welcome. Signed-off-by: Sebastian Krzyszkowiak Signed-off-by: Martin Kepplinger Signed-off-by: Shawn Guo --- .../arm64/boot/dts/freescale/imx8mq-librem5-r3.dts | 2 +- arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi | 22 ++++++++++++++++------ 2 files changed, 17 insertions(+), 7 deletions(-) diff --git a/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts b/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts index 4533a84..077c5cd 100644 --- a/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts +++ b/arch/arm64/boot/dts/freescale/imx8mq-librem5-r3.dts @@ -7,7 +7,7 @@ &a53_opp_table { opp-1000000000 { - opp-microvolt = <1000000>; + opp-microvolt = <950000>; }; }; diff --git a/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi b/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi index 509776a..eaf35cf 100644 --- a/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi +++ b/arch/arm64/boot/dts/freescale/imx8mq-librem5.dtsi @@ -839,8 +839,8 @@ regulator-max-microvolt = <1300000>; regulator-boot-on; regulator-ramp-delay = <1250>; - rohm,dvs-run-voltage = <900000>; - rohm,dvs-idle-voltage = <850000>; + rohm,dvs-run-voltage = <880000>; + rohm,dvs-idle-voltage = <820000>; rohm,dvs-suspend-voltage = <800000>; regulator-always-on; }; @@ -851,8 +851,8 @@ regulator-max-microvolt = <1300000>; regulator-boot-on; regulator-ramp-delay = <1250>; - rohm,dvs-run-voltage = <1000000>; - rohm,dvs-idle-voltage = <900000>; + rohm,dvs-run-voltage = <950000>; + rohm,dvs-idle-voltage = <850000>; regulator-always-on; }; @@ -861,14 +861,14 @@ regulator-min-microvolt = <700000>; regulator-max-microvolt = <1300000>; regulator-boot-on; - rohm,dvs-run-voltage = <900000>; + rohm,dvs-run-voltage = <850000>; }; buck4_reg: BUCK4 { regulator-name = "buck4"; regulator-min-microvolt = <700000>; regulator-max-microvolt = <1300000>; - rohm,dvs-run-voltage = <1000000>; + rohm,dvs-run-voltage = <930000>; }; buck5_reg: BUCK5 { @@ -1403,3 +1403,13 @@ fsl,ext-reset-output; status = "okay"; }; + +&a53_opp_table { + opp-1000000000 { + opp-microvolt = <850000>; + }; + + opp-1500000000 { + opp-microvolt = <950000>; + }; +}; -- 2.7.4