linux-kernel - [PATCH 02/10] arm64: dts: imx8mp-skov: operate CPU at 850 mV by default

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241219-skov-dt-updates-v1-2-38bf80dc22df@pengutronix.de>
Date: Thu, 19 Dec 2024 08:25:26 +0100
From: Ahmad Fatoum <a.fatoum@...gutronix.de>
To: Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>, Shawn Guo <shawnguo@...nel.org>, 
 Sascha Hauer <s.hauer@...gutronix.de>, 
 Pengutronix Kernel Team <kernel@...gutronix.de>, 
 Fabio Estevam <festevam@...il.com>, 
 Oleksij Rempel <o.rempel@...gutronix.de>
Cc: devicetree@...r.kernel.org, imx@...ts.linux.dev, 
 linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org, 
 kernel@...gutronix.de, Ahmad Fatoum <a.fatoum@...gutronix.de>
Subject: [PATCH 02/10] arm64: dts: imx8mp-skov: operate CPU at 850 mV by
 default

The Skov i.MX8MP boards are passively cooled and heatsink is specced for
continuous operation at 1.2 GHz only. Short bouts of 1.6 GHz are ok,
but these should be invoked intentionally, not as part of
suspend/resume cycles.

Therefore, configure RUN frequency as 850 mV and remove the higher
voltage operating points from those permissible for suspend.

Fixes: 6d382d51d979 ("arm64: dts: freescale: Add SKOV IMX8MP CPU revB board")
Signed-off-by: Ahmad Fatoum <a.fatoum@...gutronix.de>
---
 arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi b/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi
index ae82166b5c26..7ae686d37dda 100644
--- a/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi
+++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi
@@ -163,6 +163,19 @@ reg_vsd_3v3: regulator-vsd-3v3 {
 	};
 };
 
+/*
+ * Board is passively cooled and heatsink is specced for continuous operation
+ * at 1.2 GHz only. Short bouts of 1.6 GHz are ok, but these should be done
+ * intentionally, not as part of suspend/resume cycles.
+ */
+&{/opp-table/opp-1600000000} {
+	/delete-property/ opp-suspend;
+};
+
+&{/opp-table/opp-1800000000} {
+	/delete-property/ opp-suspend;
+};
+
 &A53_0 {
 	cpu-supply = <&reg_vdd_arm>;
 };
@@ -253,7 +266,7 @@ reg_vdd_arm: BUCK2 {
 				regulator-boot-on;
 				regulator-always-on;
 				regulator-ramp-delay = <3125>;
-				nxp,dvs-run-voltage = <950000>;
+				nxp,dvs-run-voltage = <850000>;
 				nxp,dvs-standby-voltage = <850000>;
 			};
 

-- 
2.39.5