linux-kernel - Re: [PATCH v2 4/4] arm64: dts: mt7622: group clock DT nodes into separate DT file

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Tue, 30 May 2017 09:16:32 +0800
From:   Sean Wang <sean.wang@...iatek.com>
To:     Matthias Brugger <matthias.bgg@...il.com>
CC:     <robh+dt@...nel.org>, <mark.rutland@....com>,
        <devicetree@...r.kernel.org>, <linux-mediatek@...ts.infradead.org>,
        <linux-arm-kernel@...ts.infradead.org>,
        <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 4/4] arm64: dts: mt7622: group clock DT nodes into
 separate DT file

On Mon, 2017-05-29 at 17:09 +0200, Matthias Brugger wrote:
> 
> On 29/05/17 14:56, sean.wang@...iatek.com wrote:
> > From: Sean Wang <sean.wang@...iatek.com>
> > 
> > For more readability and maintenance, all the clock related DT
> > nodes for mt7622 SoC are grouped into a separate DT file. And
> > currently mt7622-clock.dtsi only includes the fixed clock for
> > uart0 and the oscillator which would be extended after MT7622
> > clock driver is introduced.
> > 
> 
> We've not done this for any other Mediatek SoC at the moment.
> Do you expect the m7622 to have more clock nodes then for example mt7623?


clocks on mt7622 has fewer nodes than mt7623

> Apart from that this clock nodes are just dummy clocks which should 
> disappear as soon as the clock driver got merged.
> Last point, you break bisectability if add a clock node in a patch 
> *after* the consumer was added.
> 
> So please add the clock nodes to the dtsi as we did up to now. If in the 
> future we see that mt7622 has a whole bunch of clock nodes, we can still 
> abstract them in an external dtsi file.
> 

Okay, I will merge back them into the main dtsi files for those reasons
in the next version. 


Appreciate all your reviewing and suggestions

	Sean

> Thanks,
> Matthias
> 
> > Signed-off-by: Sean Wang <sean.wang@...iatek.com>
> > ---
> >   arch/arm64/boot/dts/mediatek/mt7622-clock.dtsi | 20 ++++++++++++++++++++
> >   arch/arm64/boot/dts/mediatek/mt7622.dtsi       |  1 +
> >   2 files changed, 21 insertions(+)
> >   create mode 100644 arch/arm64/boot/dts/mediatek/mt7622-clock.dtsi
> > 
> > diff --git a/arch/arm64/boot/dts/mediatek/mt7622-clock.dtsi b/arch/arm64/boot/dts/mediatek/mt7622-clock.dtsi
> > new file mode 100644
> > index 0000000..264421d
> > --- /dev/null
> > +++ b/arch/arm64/boot/dts/mediatek/mt7622-clock.dtsi
> > @@ -0,0 +1,20 @@
> > +/*
> > + * Copyright (c) 2017 MediaTek Inc.
> > + * Author: Sean Wang <sean.wang@...iatek.com>
> > + *
> > + * SPDX-License-Identifier: (GPL-2.0 OR MIT)
> > + */
> > +/ {
> > +	clk25m: oscillator@0 {
> > +		compatible = "fixed-clock";
> > +		#clock-cells = <0>;
> > +		clock-frequency = <25000000>;
> > +		clock-output-names = "clkxtal";
> > +	};
> > +
> > +	uart_clk: dummy26m {
> > +		compatible = "fixed-clock";
> > +		#clock-cells = <0>;
> > +		clock-frequency = <25000000>;
> > +	};
> > +};
> > diff --git a/arch/arm64/boot/dts/mediatek/mt7622.dtsi b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > index 3a729d9..3768c28 100644
> > --- a/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > +++ b/arch/arm64/boot/dts/mediatek/mt7622.dtsi
> > @@ -8,6 +8,7 @@
> >   
> >   #include <dt-bindings/interrupt-controller/irq.h>
> >   #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +#include "mt7622-clock.dtsi"
> >   
> >   / {
> >   	compatible = "mediatek,mt7622";
> >