Re: [PATCH v3 0/2] arm: remove cpu_efficiency

From: Dietmar Eggemann
Date: Tue Oct 24 2017 - 10:32:02 EST


Hi Russel,

Thanks for the review!

On 24/10/17 11:52, Russell King - ARM Linux wrote:
> On Tue, Oct 24, 2017 at 11:27:16AM +0100, Dietmar Eggemann wrote:
>> With the dt related patches for exynos and renesas now in the
>> appropriated for-next branches for v4.15 there are no Cortex-A15/A7 arm
>> big.LITTLE systems left relying on the 'cpu_efficiency/clock-frequency
>> dt property' based solution anymore.
>
> This is way too early to remove support for something that has been
> in place since 2012. As you've just shown, people are using it with
> DT files today. We don't know how long people will persist using
> older files, and we don't know whether there are DT files out in the
> wild that we don't know about.

Understood. But do we really care about out of tree dt files?

In case the mentioned exynos and renesas Cortex-A15/A7 platforms change
to using 'capacity-dmips-mhz' in v4.15 there shouldn't be any
Cortex-A15/A7 platforms in mainline left using the cpu_efficiency
solution anymore.

> Our general rule is that we maintain compatibility for older DT.

OK.

> NAK.

Then I still send out [2/2] separately.