RE: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller RTC support

[Anson Huang]

Hi, Lothar

Best Regards!
Anson Huang

> -----Original Message-----
> From: Lothar WaÃmann [mailto:LW@xxxxxxxxxxxxxxxxxxx]
> Sent: 2018å11æ28æ 17:13
> To: Anson Huang <anson.huang@xxxxxxx>
> Cc: a.zummo@xxxxxxxxxxxx; alexandre.belloni@xxxxxxxxxxx;
> robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; catalin.marinas@xxxxxxx;
> will.deacon@xxxxxxx; Aisheng DONG <aisheng.dong@xxxxxxx>; Andy Gross
> <andy.gross@xxxxxxxxxx>; arnd@xxxxxxxx; horms+renesas@xxxxxxxxxxxx;
> heiko@xxxxxxxxx; bjorn.andersson@xxxxxxxxxx; enric.balletbo@xxxxxxxxxxxxx;
> amit.kucheria@xxxxxxxxxx; ezequiel@xxxxxxxxxxxxx; olof@xxxxxxxxx;
> shawnguo@xxxxxxxxxx; linux-rtc@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> dl-linux-imx <linux-imx@xxxxxxx>
> Subject: Re: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller
> RTC support
> 
> Anson Huang <anson.huang@xxxxxxx> wrote:
> 
> > Hi, Lothar
> >
> > Best Regards!
> > Anson Huang
> >
> > > -----Original Message-----
> > > From: Lothar WaÃmann [mailto:LW@xxxxxxxxxxxxxxxxxxx]
> > > Sent: 2018å11æ28æ 17:04
> > > To: Anson Huang <anson.huang@xxxxxxx>
> > > Cc: a.zummo@xxxxxxxxxxxx; alexandre.belloni@xxxxxxxxxxx;
> > > robh+dt@xxxxxxxxxx; mark.rutland@xxxxxxx; catalin.marinas@xxxxxxx;
> > > will.deacon@xxxxxxx; Aisheng DONG <aisheng.dong@xxxxxxx>; Andy
> Gross
> > > <andy.gross@xxxxxxxxxx>; arnd@xxxxxxxx; horms+renesas@xxxxxxxxxxxx;
> > > heiko@xxxxxxxxx; bjorn.andersson@xxxxxxxxxx;
> > > enric.balletbo@xxxxxxxxxxxxx; amit.kucheria@xxxxxxxxxx;
> > > ezequiel@xxxxxxxxxxxxx; olof@xxxxxxxxx; shawnguo@xxxxxxxxxx;
> > > linux-rtc@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx;
> > > linux-kernel@xxxxxxxxxxxxxxx; linux-arm-kernel@xxxxxxxxxxxxxxxxxxx;
> > > dl-linux-imx <linux-imx@xxxxxxx>
> > > Subject: Re: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system
> > > controller RTC support
> > >
> > > Hi,
> > >
> > > On Tue, 27 Nov 2018 09:41:46 +0000 Anson Huang wrote:
> > > > Add i.MX8QXP system controller RTC support.
> > > >
> > > > Signed-off-by: Anson Huang <Anson.Huang@xxxxxxx>
> > > > ---
> > > >  arch/arm64/boot/dts/freescale/imx8qxp.dtsi | 4 ++++
> > > >  1 file changed, 4 insertions(+)
> > > >
> > > > diff --git a/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
> > > b/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
> > > > index 9155d45..ef57db6 100644
> > > > --- a/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
> > > > +++ b/arch/arm64/boot/dts/freescale/imx8qxp.dtsi
> > > > @@ -433,4 +433,8 @@
> > > >  		#size-cells = <1>;
> > > >  		ranges = <0x5f000000 0x0 0x5f000000 0x1000000>;
> > > >  	};
> > > > +
> > > > +	rtc: rtc {
> > > > +		compatible = "nxp,imx8qxp-sc-rtc";
> > > > +	};
> > > >  };
> > > IMO this should be disabled by default.
> >
> > This module is NOT depending on any board design, should it be enabled by
> default in soc dtsi?
> > Like wdog etc..
> >
> What about existing users (if there are any), which would have a new device
> appearing when updating the DTB?

This i.MX8QXP is a new SoC on the way to upstream, no old dtb used, so is it OK to keep it enabled
by default and aligned with all previous i.MX SoCs' RTC implementation? If we disable it
here, we have to enable it in all boards dtb. So if it is NOT very critical, is it OK to keep
it enabled by default here? Thanks.

Anson

> 
> 
> Lothar WaÃmann
> --
> ___________________________________________________________
> 
> Ka-Ro electronics GmbH | PascalstraÃe 22 | D - 52076 Aachen
> Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10
> GeschÃftsfÃhrer: Matthias Kaussen
> Handelsregistereintrag: Amtsgericht Aachen, HRB 4996
> 
> https://emea01.safelinks.protection.outlook.com/?url=www.karo-electronics.d
> e&amp;data=02%7C01%7Canson.huang%40nxp.com%7C12fb8e546a0e46d03
> 72408d65511a43f%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C
> 636789931600483807&amp;sdata=SVZjpvYsi9XAM7CGt8sHZ5mt8rPRa%2FPl
> 75EQvHTod%2Bg%3D&amp;reserved=0 | info@xxxxxxxxxxxxxxxxxxx
> ___________________________________________________________