Re: FAILED: patch "[PATCH] arm64: dts: rockchip: remove vdd_log from rock960 to fix a" failed to apply to 4.19-stable tree

[Sasha Levin <sashal@kernel.org>]

On Thu, Dec 06, 2018 at 09:36:33AM +0100, gregkh@linuxfoundation.org wrote:
>
>The patch below does not apply to the 4.19-stable tree.
>If someone wants it applied there, or to any other stable or longterm
>tree, then please email the backport, including the original git commit
>id to <stable@vger.kernel.org>.
>
>thanks,
>
>greg k-h
>
>------------------ original commit in Linus's tree ------------------
>
>>From 13682e524167cbd7e2a26c5e91bec765f0f96273 Mon Sep 17 00:00:00 2001
>From: Daniel Lezcano <daniel.lezcano@linaro.org>
>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 <manivannan.sadhasivam@linaro.org>
>Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
>Signed-off-by: Heiko Stuebner <heiko@sntech.de>
>
>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 {

The definition is just located in a different file in 4.19 (it was moved
by ffb7b25e8ac3 ("arm64: dts: rockchip: Split out common nodes for Rock960
based boards") ).

I've adjusted it and queued it for 4.19.

--
Thanks,
Sasha