On Tue, Oct 05, 2021 at 03:10:14PM +0200, Frieder Schrempf wrote:

On 05.10.21 08:53, Shawn Guo wrote:

quoted

On Thu, Sep 30, 2021 at 05:56:25PM +0200, Frieder Schrempf wrote:

quoted

From: Frieder Schrempf <redacted>

VDD_SOC should be 800 mV in suspend and 850 mV in run mode. VDD_DRAM
should be 950 mV for DDR clock frequencies of 1.5 GHz.

This information is taken from the datasheet and the uboot-imx code.

I'm wondering where the existing settings were coming from?

Good question, but I can't really retrace now how I actually determined
the values back then. Seems like I had failed to validate them properly.

Please update commit log with these background info.

Shawn

quoted

quoted

Signed-off-by: Frieder Schrempf <redacted>
---
 arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-som.dtsi | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-som.dtsi b/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-som.dtsi
index 03b3516abd64..b12fb7ce6686 100644
--- a/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-som.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mm-kontron-n801x-som.dtsi

@@ -92,10 +92,12 @@ regulators {
 			reg_vdd_soc: BUCK1 {
 				regulator-name = "buck1";
 				regulator-min-microvolt = <800000>;
-				regulator-max-microvolt = <900000>;
+				regulator-max-microvolt = <850000>;
 				regulator-boot-on;
 				regulator-always-on;
 				regulator-ramp-delay = <3125>;
+				nxp,dvs-run-voltage = <850000>;
+				nxp,dvs-standby-voltage = <800000>;
 			};
 
 			reg_vdd_arm: BUCK2 {

@@ -111,7 +113,7 @@ reg_vdd_arm: BUCK2 {
 			reg_vdd_dram: BUCK3 {
 				regulator-name = "buck3";
 				regulator-min-microvolt = <850000>;
-				regulator-max-microvolt = <900000>;
+				regulator-max-microvolt = <950000>;
 				regulator-boot-on;
 				regulator-always-on;
 			};

-- 
2.33.0