[PATCH v5 0/5] ARM: EXYNOS: cpuidle: fix AFTR mode on boards with secure firmware enabled
k.kozlowski at samsung.com
Tue Aug 5 07:26:23 PDT 2014
On 05.08.2014 16:03, Daniel Lezcano wrote:
> On 08/05/2014 03:34 PM, Bartlomiej Zolnierkiewicz wrote:
>> This patch series adds support for AFTR idle mode on boards with
>> secure firmware enabled and allows EXYNOS cpuidle driver usage on
>> Exynos4x12 SoCs.
>> It has been tested on Trats2 board (using Exynos4412 SoC with secure
>> firmware enabled) on which AFTR mode reduces power consumption by ~12%
>> when EXYNOS cpuidle driver is enabled (in both cases the default
>> exynos_defconfig config is used and CPU1-3 are offlined).
> As a sidenote:
> On my odroid-U2:
> * 4 cpus online -> 130 mA
> * 3 cpus online -> 164 mA
> * 2 cpus online -> 160 mA
> * 1 cpu online -> 157 mA
> So were are consuming more when there are unplugged cpu ... any ideas ?
On which tree are you testing? Current next has ARMCLK down feature
enabled. ARMCLK down may stop working after hotunplugging CPU:
That was observed especially on Exynos4212 where ARMCLK down stops
working permanently. On Trats2 (Exynos4412) the clock down stopped only
a for short period after disabling CPU.
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