From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754139AbbDNKHQ (ORCPT ); Tue, 14 Apr 2015 06:07:16 -0400 Received: from foss.arm.com ([217.140.101.70]:33562 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753038AbbDNKHJ (ORCPT ); Tue, 14 Apr 2015 06:07:09 -0400 Date: Tue, 14 Apr 2015 11:06:58 +0100 From: Mark Rutland To: Yong Wu Cc: Rob Herring , Joerg Roedel , Matthias Brugger , Robin Murphy , Will Deacon , Daniel Kurtz , Tomasz Figa , Lucas Stach , Catalin Marinas , "linux-mediatek@lists.infradead.org" , Sasha Hauer , "srv_heupstream@mediatek.com" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "iommu@lists.linux-foundation.org" Subject: Re: [PATCH 3/5] dt-bindings: mediatek: Add smi dts binding Message-ID: <20150414100657.GB28709@leverpostej> References: <1425638900-24989-1-git-send-email-yong.wu@mediatek.com> <1425638900-24989-4-git-send-email-yong.wu@mediatek.com> <20150306111338.GD8700@leverpostej> <1429002474.14855.7.camel@mhfsdcap03> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <1429002474.14855.7.camel@mhfsdcap03> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 14, 2015 at 10:07:54AM +0100, Yong Wu wrote: > Hi Mark, > Thanks very much for review. > About the clock name should be the PoV of _this_ device. Could you > help check below? > > On Fri, 2015-03-06 at 11:13 +0000, Mark Rutland wrote: > > On Fri, Mar 06, 2015 at 10:48:18AM +0000, yong.wu@mediatek.com wrote: > > > From: Yong Wu > > > > > > This patch add smi binding document. > > > > Please move binding documents to the start of the series. It makes > > things far easier to review. > > > > > > > > Signed-off-by: Yong Wu > > > +++ b/Documentation/devicetree/bindings/soc/mediatek/mediatek,smi.txt > > > @@ -0,0 +1,17 @@ > > > +SMI hardware block diagram please help check > > > + > > > +Required properties: > > > +- compatible : must be "mediatek,mediatek,mt8173-smi-larb" > > > > Double vendor prefix? > > > > What does "larb" mean? It would be nice for the intorductory paragraph > > in this file to explain. > > > > > +- reg : the register of each local arbiter > > > +- clocks : the clocks of each local arbiter > > > +- clock-name: larb_sub*(3 clockes at most) > > > > The names required _must_ be specified here, or clock-names is > > pointless. > > > > The clock names should be from the PoV of _this_ device (i.e. they > > should be the names of the inputs) not from the PoV of the provider > > (i.e. they should not be the names of the outputs from the provider). > > > > Mark. > > > After we check with our SMI Designer. Every SMI local arbiter need > two clocks, which is called APB clocks and SMI clock. > APB clock : Advanced Peripheral Bus Clock. It is the clock for > setting the register of local arbiter. > SMI clock : Smart Multimedia Interface Clock, It is the clock for > transfering the data and command. > > And all the local arbiters need the smi common clock, so we > separate it. > > Then I prepare to design the smi the dtsi like this: > > smi_common:smi@14022000 { > compatible = “mediate, mt8173-smi”; > reg = <0 0x14022000 0 0x1000>; > clocks = <&mmsys MM_SMI_COMMON>; > clocks-names = “smi_common”; > }; > > larb0: larb@14021000 { > compatible = “mediate, mt8173-smi-larb”; > reg = <0 0x14021000 0 0x1000>; > smi = <&smi_common>; > clocks = <&mmsys MM_SMI_LARB0>, > <&mmsys MM_SMI_LARB0>; > clocks-names = “apb_clk”, “smi_clk”; > }; > > larb1: larb@16010000 { > compatible = “mediate, mt8173-smi-larb”; > reg = <0 0x16010000 0 0x1000>; > smi = <&smi_common>; > clocks = <&vdecsys VDEC_CKEN>, > <&mmsys VDEC_LARB_CKEN>; > clocks-names = “apb_clk”, “smi_clk”; > }; > … > In some local arbiter, the source clock of the APB clock and the > SMI clock may be the same, like larb0. so the two clocks are the same. > And they may be different in other local arbiteres, like larb1. > > If it is designed like this, is it ok? That looks pretty good; the clocks and names on the larb nodes seem sensible. The naming of the "smi_common" clock on the smi_common node looks a bit odd though. Is that really what the clock input is called? Mark.