[PATCH] arm64: dts: juno: fix cluster sleep state entry latency on all SoC versions
Liviu Dudau
liviu.dudau at arm.com
Mon Nov 14 09:32:52 PST 2016
On Mon, Nov 14, 2016 at 03:26:29PM +0000, Sudeep Holla wrote:
> The core and the cluster sleep state entry latencies can't be same as
> cluster sleep involves more work compared to core level e.g. shared
> cache maintenance.
>
> Experiments have shown on an average about 100us more latency for the
> cluster sleep state compared to the core level sleep. This patch fixes
> the entry latency for the cluster sleep state.
>
> Fixes: 28e10a8f3a03 ("arm64: dts: juno: Add idle-states to device tree")
> Cc: Liviu Dudau <liviu.dudau at arm.com>
> Cc: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
> Cc: "Jon Medhurst (Tixy)" <tixy at linaro.org>
> Signed-off-by: Sudeep Holla <sudeep.holla at arm.com>
Looks sensible to me.
Reviewed-by: Liviu Dudau <Liviu.Dudau at arm.com>
> ---
> arch/arm64/boot/dts/arm/juno-r1.dts | 2 +-
> arch/arm64/boot/dts/arm/juno-r2.dts | 2 +-
> arch/arm64/boot/dts/arm/juno.dts | 2 +-
> 3 files changed, 3 insertions(+), 3 deletions(-)
>
> Hi,
>
> This was found recently when I found that core sleep was chosen when
> entering suspend-to-idle state on Juno. Since the wakeup(entry+exit)
> latency matched for the both states, cpu sleep state was chosen to enter
> in suspend-to-idle.
>
> Regards,
> Sudeep
>
> diff --git a/arch/arm64/boot/dts/arm/juno-r1.dts b/arch/arm64/boot/dts/arm/juno-r1.dts
> index 3be8a3ef671c..eec37feee8fc 100644
> --- a/arch/arm64/boot/dts/arm/juno-r1.dts
> +++ b/arch/arm64/boot/dts/arm/juno-r1.dts
> @@ -76,7 +76,7 @@
> compatible = "arm,idle-state";
> arm,psci-suspend-param = <0x1010000>;
> local-timer-stop;
> - entry-latency-us = <300>;
> + entry-latency-us = <400>;
> exit-latency-us = <1200>;
> min-residency-us = <2500>;
> };
> diff --git a/arch/arm64/boot/dts/arm/juno-r2.dts b/arch/arm64/boot/dts/arm/juno-r2.dts
> index 614fc9227943..28f40ec44090 100644
> --- a/arch/arm64/boot/dts/arm/juno-r2.dts
> +++ b/arch/arm64/boot/dts/arm/juno-r2.dts
> @@ -76,7 +76,7 @@
> compatible = "arm,idle-state";
> arm,psci-suspend-param = <0x1010000>;
> local-timer-stop;
> - entry-latency-us = <300>;
> + entry-latency-us = <400>;
> exit-latency-us = <1200>;
> min-residency-us = <2500>;
> };
> diff --git a/arch/arm64/boot/dts/arm/juno.dts b/arch/arm64/boot/dts/arm/juno.dts
> index 6b4135e9cfe5..ac5ceb73f45f 100644
> --- a/arch/arm64/boot/dts/arm/juno.dts
> +++ b/arch/arm64/boot/dts/arm/juno.dts
> @@ -76,7 +76,7 @@
> compatible = "arm,idle-state";
> arm,psci-suspend-param = <0x1010000>;
> local-timer-stop;
> - entry-latency-us = <300>;
> + entry-latency-us = <400>;
> exit-latency-us = <1200>;
> min-residency-us = <2500>;
> };
> --
> 2.7.4
>
--
====================
| I would like to |
| fix the world, |
| but they're not |
| giving me the |
\ source code! /
---------------
¯\_(ツ)_/¯
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