[PATCH 6/6] riscv: dts: spacemit: k1-bananapi-cm6: fix maximum CPU core voltage

Aurelien Jarno <[email protected]> Wed, 29 Jul 2026 17:02:23 +0200
Newsgroups dev.linux.lists.spacemit,org.infradead.lists.linux-riscv,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On the Banana Pi BPI-CM6 module, the buck1 and buck2 voltage regulators,
which supply the CPU core voltage, are configured with a maximum output
voltage of 3.45V, while the highest operating point requires only
1.050V. This means that a kernel bug, OPP misconfiguration, or
privileged userspace could request a voltage above the safe operating
limit, causing possible permanent CPU damage.

Set the maximum regulator voltage to 1.050V instead.

Fixes: 46a8c01700ac ("riscv: dts: spacemit: k1: Add Banana Pi BPI-CM6 IO board")
Link: https://sashiko.dev/#/message/20260728211020.1248676-2-aurelien%40aurel32.net
Signed-off-by: Aurelien Jarno <[email protected]>
---
 arch/riscv/boot/dts/spacemit/k1-bananapi-cm6.dtsi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/boot/dts/spacemit/k1-bananapi-cm6.dtsi b/arch/riscv/boot/dts/spacemit/k1-bananapi-cm6.dtsi
index bf502c87040a3..81c40df2a3663 100644
--- a/arch/riscv/boot/dts/spacemit/k1-bananapi-cm6.dtsi
+++ b/arch/riscv/boot/dts/spacemit/k1-bananapi-cm6.dtsi
@@ -114,14 +114,14 @@ pmic@41 {
 		regulators {
 			buck1 {
 				regulator-min-microvolt = <500000>;
-				regulator-max-microvolt = <3450000>;
+				regulator-max-microvolt = <1050000>;
 				regulator-ramp-delay = <5000>;
 				regulator-always-on;
 			};
 
 			buck2 {
 				regulator-min-microvolt = <500000>;
-				regulator-max-microvolt = <3450000>;
+				regulator-max-microvolt = <1050000>;
 				regulator-ramp-delay = <5000>;
 				regulator-always-on;
 			};
-- 
2.53.0