From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1031864AbbKEDCx (ORCPT <rfc822;w@1wt.eu>);
	Wed, 4 Nov 2015 22:02:53 -0500
Received: from mail.kernel.org ([198.145.29.136]:35172 "EHLO mail.kernel.org"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S965762AbbKEDCv (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Wed, 4 Nov 2015 22:02:51 -0500
Date: Wed, 4 Nov 2015 21:02:45 -0600
From: Rob Herring <robh@kernel.org>
To: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Rafael Wysocki <rjw@rjwysocki.net>, robh+dt@kernel.org,
        sboyd@codeaurora.org, lee.jones@linaro.org,
        linaro-kernel@lists.linaro.org, linux-pm@vger.kernel.org,
        mark.rutland@arm.com, pawel.moll@arm.com,
        ijc+devicetree@hellion.org.uk, galak@codeaurora.org, nm@ti.com,
        devicetree@vger.kernel.org, b.zolnierkie@samsung.com,
        m.szyprowski@samsung.com, open list <linux-kernel@vger.kernel.org>,
        "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Subject: Re: [PATCH V2 2/5] PM / OPP: Add
 {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding
Message-ID: <20151105030245.GA20613@rob-hp-laptop>
References: <cover.1446687367.git.viresh.kumar@linaro.org>
 <17a4388be606f21fe1d31b23180d41f6cabdd4b5.1446687367.git.viresh.kumar@linaro.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <17a4388be606f21fe1d31b23180d41f6cabdd4b5.1446687367.git.viresh.kumar@linaro.org>
User-Agent: Mutt/1.5.23 (2014-03-12)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Thu, Nov 05, 2015 at 07:11:53AM +0530, Viresh Kumar wrote:
> Depending on the version of hardware or its properties, which are only
> known at runtime, various properties of the OPP can change. For example,
> an OPP with frequency 1.2 GHz, may have different voltage/current
> requirements based on the version of the hardware it is running on.
> Similarly, it may or may not be a turbo or suspend OPP on those
> circumstances.
> 
> In order to not replicate the same OPP tables for varying values of all
> such fields, this commit introduces the concept of opp-property-<name>.
> The <name> can be chosen by the platform at runtime, and OPPs will be
> initialized depending on that name string. Currently support is extended
> for the following properties:
> - opp-microvolt-<name>
> - opp-microamp-<name>
> - turbo-mode-<name>
> - opp-suspend-<name>
> 
> If the name string isn't provided by the platform, or if it is provided
> but doesn't match the properties present in the OPP node, we will fall
> back to the original properties without the -<name> string, if they are
> available.
> 
> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  Documentation/devicetree/bindings/opp/opp.txt | 58 +++++++++++++++++++++++++++
>  1 file changed, 58 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
> index d072fa0ffbd4..61c6f25cf8e2 100644
> --- a/Documentation/devicetree/bindings/opp/opp.txt
> +++ b/Documentation/devicetree/bindings/opp/opp.txt
> @@ -100,6 +100,14 @@ properties.
>    Entries for multiple regulators must be present in the same order as
>    regulators are specified in device's DT node.
>  
> +- opp-microvolt-<name>: Named opp-microvolt property. This is exactly similar to
> +  the above opp-microvolt property, but allows multiple voltage ranges to be
> +  provided for the same OPP. At runtime, the platform can pick a <name> and
> +  matching opp-microvolt-<name> property will be enabled for all OPPs. If the
> +  platform doesn't pick a specific <name> or the <name> doesn't match with any
> +  opp-microvolt-<name> properties, then opp-microvolt property shall be used, if
> +  present.
> +
>  - opp-microamp: The maximum current drawn by the device in microamperes
>    considering system specific parameters (such as transients, process, aging,
>    maximum operating temperature range etc.) as necessary. This may be used to
> @@ -112,6 +120,9 @@ properties.
>    for few regulators, then this should be marked as zero for them. If it isn't
>    required for any regulator, then this property need not be present.
>  
> +- opp-microamp-<name>: Named opp-microamp property. Similar to
> +  opp-microvolt-<name> property, but for microamp instead.
> +
>  - clock-latency-ns: Specifies the maximum possible transition latency (in
>    nanoseconds) for switching to this OPP from any other OPP.
>  
> @@ -120,9 +131,15 @@ properties.
>    frequency for a short duration of time limited by the device's power, current
>    and thermal limits.
>  
> +- turbo-mode-<name>: Named turbo-mode property. Similar to opp-microvolt-<name>
> +  property, but for turbo mode instead.
> +
>  - opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
>    the table should have this.
>  
> +- opp-suspend-<name>: Named opp-suspend property. Similar to
> +  opp-microvolt-<name> property, but for suspend opp instead.
> +

I don't think these last 2 make sense. turbo-mode is a flag that the 
mode has restrictions such as other cores have to be idle or something. 
Similarly, opp-suspend should not vary by <name>.

Rob