From 13682e524167cbd7e2a26c5e91bec765f0f96273 Mon Sep 17 00:00:00 2001 From: Daniel Lezcano Date: Wed, 17 Oct 2018 11:18:30 +0200 Subject: [PATCH] arm64: dts: rockchip: remove vdd_log from rock960 to fix a stability issues When the performance governor is set as default, the rock960 hangs around one minute after booting, whatever the activity is (idle, key pressed, loaded, ...). Based on the commit log found at https://patchwork.kernel.org/patch/10092377/ "vdd_log has no consumer and therefore will not be set to a specific voltage. Still the PWM output pin gets configured and thence the vdd_log output voltage will changed from it's default. Depending on the idle state of the PWM this will slightly over or undervoltage the logic supply of the RK3399 and cause instability with GbE (undervoltage) and PCIe (overvoltage). Since the default value set by a voltage divider is the correct supply voltage and we don't need to change it during runtime we remove the rail from the devicetree completely so the PWM pin will not be configured." After removing the vdd-log from the rock960's specific DT, the board does no longer hang and shows a stable behavior. Apply the same change for the rock960 by removing the vdd-log from the DT. Fixes: 874846f1fccd ("arm64: dts: rockchip: add 96boards RK3399 Ficus board") Cc: stable@vger.kernel.org Tested-by: Manivannan Sadhasivam Signed-off-by: Daniel Lezcano Signed-off-by: Heiko Stuebner --- arch/arm64/boot/dts/rockchip/rk3399-rock960.dtsi | 12 ------------ 1 file changed, 12 deletions(-) diff --git a/arch/arm64/boot/dts/rockchip/rk3399-rock960.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-rock960.dtsi index 6c8c4ab044aa..56abbb08c133 100644 --- a/arch/arm64/boot/dts/rockchip/rk3399-rock960.dtsi +++ b/arch/arm64/boot/dts/rockchip/rk3399-rock960.dtsi @@ -57,18 +57,6 @@ regulator-always-on; vin-supply = <&vcc_sys>; }; - - vdd_log: vdd-log { - compatible = "pwm-regulator"; - pwms = <&pwm2 0 25000 0>; - regulator-name = "vdd_log"; - regulator-min-microvolt = <800000>; - regulator-max-microvolt = <1400000>; - regulator-always-on; - regulator-boot-on; - vin-supply = <&vcc_sys>; - }; - }; &cpu_l0 { -- 2.30.2