From: Benoit Cousson <bcousson@baylibre.com>
To: linux-sh@vger.kernel.org
Subject: Re: [PATCH 3/7] ARM: shmobile: Disable DVS support for r8a7790
Date: Mon, 02 Jun 2014 07:11:01 +0000 [thread overview]
Message-ID: <538C2385.40702@baylibre.com> (raw)
In-Reply-To: <5386E66D.3020502@bp.renesas.com>
Hi,
On 02/06/2014 05:14, Gaku Inami wrote:
> Hi Geert
>
> Thank you for your feedback.
>
>> The role of the DT is to describe the hardware.
>> Not using DVS because the effect of power consumption is low or non-existent
>> is a software policy.
>>
>> So perhaps it should be kept?
>
> I understand what you mean. I will keep the setting of VDD into DT,
> and consider to disable DVS in a different way.
>
Indeed, the line "cpu0-supply = <&vdd_dvfs>;" does just provide the name
of the power rail that supply the ca15 cluster.
The postfix _dvfs is a little bit misleading in this case, I do agree.
If you do no want voltage scaling, it is just a matter of keeping the
same voltage in the OPP table. This is what I have done in the series I
sent a while back.
That being said, what is the exact voltage range supported by the CPU?
AFAIR, with 28nm process some SoCs are able to scale down to 0.9v.
Thanks,
Benoit
--
Benoît Cousson
BayLibre
Embedded Linux Technology Lab
www.baylibre.com
next prev parent reply other threads:[~2014-06-02 7:11 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-05-29 7:49 [PATCH 3/7] ARM: shmobile: Disable DVS support for r8a7790 Gaku Inami
2014-05-29 16:00 ` Sergei Shtylyov
2014-05-30 2:23 ` Gaku Inami
2014-05-30 9:58 ` Geert Uytterhoeven
2014-06-02 3:14 ` Gaku Inami
2014-06-02 7:11 ` Benoit Cousson [this message]
2014-06-02 8:58 ` Gaku Inami
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