Re: [PATCH AUTOSEL for 3.18 34/63] ARM: dts: rockchip: disable arm-global-timer for rk3188

From: Alexander Kochetkov
Date: Sun Mar 04 2018 - 18:20:21 EST


Hello, Sasha!

Following 2 patches must be applied together with the patch:
5e0a39d0f727b35c8b7ef56ba0724c8ceb006297 clocksource/drivers/rockchip_timer: Implement clocksource timer
627988a66aee3c845aa2f1f874a3ddba8adb89d9 ARM: dts: rockchip: Add timer entries to rk3188 SoC

Alexander.

> 4 ÐÐÑÑÐ 2018 Ð., Ð 1:33, Sasha Levin <Alexander.Levin@xxxxxxxxxxxxx> ÐÐÐÐÑÐÐ(Ð):
>
> From: Alexander Kochetkov <al.kochet@xxxxxxxxx>
>
> [ Upstream commit 500d0aa918a2ea6bb918fee8adcf27dc2912bcd1 ]
>
> The clocksource and the sched_clock provided by the arm_global_timer
> are quite unstable because their rates depend on the cpu frequency.
>
> On the other side, the arm_global_timer has a higher rating than the
> rockchip_timer, it will be selected by default by the time framework
> while we want to use the stable rockchip clocksource.
>
> Let's disable the arm_global_timer in order to have the rockchip
> clocksource selected by default.
>
> Signed-off-by: Alexander Kochetkov <al.kochet@xxxxxxxxx>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
> Reviewed-by: Heiko Stuebner <heiko@xxxxxxxxx>
> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
> ---
> arch/arm/boot/dts/rk3188.dtsi | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/arch/arm/boot/dts/rk3188.dtsi b/arch/arm/boot/dts/rk3188.dtsi
> index ddaada788b45..72b0b4cb538f 100644
> --- a/arch/arm/boot/dts/rk3188.dtsi
> +++ b/arch/arm/boot/dts/rk3188.dtsi
> @@ -404,6 +404,7 @@
>
> &global_timer {
> interrupts = <GIC_PPI 11 0xf04>;
> + status = "disabled";
> };
>
> &local_timer {
> --
> 2.14.1