Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1751973AbdHaRjX (ORCPT <rfc822;w@1wt.eu>);
        Thu, 31 Aug 2017 13:39:23 -0400
Received: from mail-oi0-f66.google.com ([209.85.218.66]:35449 "EHLO
        mail-oi0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1751258AbdHaRjW (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Thu, 31 Aug 2017 13:39:22 -0400
X-Google-Smtp-Source: ADKCNb5b+RAe5s+8VIW1bcQsP0NGJdxhJFafEfZhalKUltvGk8MfqN2OzbWGRyM00SIoqfbJyB0r1Q==
Date: Thu, 31 Aug 2017 12:39:20 -0500
From: Rob Herring <robh@kernel.org>
To: Dong Aisheng <aisheng.dong@nxp.com>
Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, sboyd@codeaurora.org,
        vireshk@kernel.org, nm@ti.com, rjw@rjwysocki.net, shawnguo@kernel.org,
        Anson.Huang@nxp.com, ping.bai@nxp.com,
        Frank Rowand <frowand.list@gmail.com>, devicetree@vger.kernel.org
Subject: Re: [PATCH 2/7] dt-bindings: PM / OPP: add clocks per OPP node
 support
Message-ID: <20170831173920.4emtr5vkgvjcx6ac@rob-hp-laptop>
References: <1503504610-12880-1-git-send-email-aisheng.dong@nxp.com>
 <1503504610-12880-3-git-send-email-aisheng.dong@nxp.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1503504610-12880-3-git-send-email-aisheng.dong@nxp.com>
User-Agent: NeoMutt/20170113 (1.7.2)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Length: 2092
Lines: 53

On Thu, Aug 24, 2017 at 12:10:05AM +0800, Dong Aisheng wrote:
> It's used for platforms where different OPPs may use different clocks.
> With this extended binding, user could specify the correct clock for each
> OPP node.
> 
> Cc: Viresh Kumar <vireshk@kernel.org>
> Cc: Nishanth Menon <nm@ti.com>
> Cc: Stephen Boyd <sboyd@codeaurora.org>
> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Frank Rowand <frowand.list@gmail.com>
> Cc: devicetree@vger.kernel.org
> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
> ---
>  Documentation/devicetree/bindings/opp/opp.txt | 52 +++++++++++++++++++++++++++
>  1 file changed, 52 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
> index e36d261..40a4340 100644
> --- a/Documentation/devicetree/bindings/opp/opp.txt
> +++ b/Documentation/devicetree/bindings/opp/opp.txt
> @@ -152,6 +152,11 @@ Optional properties:
>    hierarchy can be contained in multiple 32 bit values. i.e. <X Y Z1 Z2> in the
>    above example, Z1 & Z2 refer to the version hierarchy Z.
>  
> +- clocks: Clock phandle and specifier used for this opp.
> +
> +- clock-names: clock names for this opp. The valid clock names are platform
> +	       specific.

You don't need -names if there's only 1 clock. But then how long until 
we have a list of any random clocks some how associated with an OPP.

I think this should really be solved within the clock framework. What 
you really need is "set my parent clock to the source that can provide X 
Hz". Could the assigned-clocks property work here (in the OPP nodes 
rather than the cpu nodes)?

> +
>  - status: Marks the node enabled/disabled.
>  
>  Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
> @@ -528,3 +533,50 @@ Example 6: opp-microvolt-<name>, opp-microamp-<name>:
>  		};
>  	};
>  };
> +
> +Example 7: Single core ARM cortex A7, switch separate clocks for each OPP:

Can't you add this to an existing example? We don't need to enumerate 
every possible option.

Rob