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

From: Anson Huang <anson.huang@nxp.com>
To: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: "Lothar Waßmann" <LW@KARO-electronics.de>,
	"a.zummo@towertech.it" <a.zummo@towertech.it>,
	"robh+dt@kernel.org" <robh+dt@kernel.org>,
	"mark.rutland@arm.com" <mark.rutland@arm.com>,
	"catalin.marinas@arm.com" <catalin.marinas@arm.com>,
	"will.deacon@arm.com" <will.deacon@arm.com>,
	"Aisheng DONG" <aisheng.dong@nxp.com>,
	"Andy Gross" <andy.gross@linaro.org>,
	"arnd@arndb.de" <arnd@arndb.de>,
	"horms+renesas@verge.net.au" <horms+renesas@verge.net.au>,
	"heiko@sntech.de" <heiko@sntech.de>,
	"bjorn.andersson@linaro.org" <bjorn.andersson@linaro.org>,
	"enric.balletbo@collabora.com" <enric.balletbo@collabora.com>,
	"amit.kucheria@linaro.org" <amit.kucheria@linaro.org>,
	"ezequiel@collabora.com" <ezequiel@collabora.com>,
	"olof@lixom.net" <olof@lixom.net>,
	"shawnguo@kernel.org" <shawnguo@kernel.org>,
	"linux-rtc@vger.kernel.org" <linux-rtc@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org"
	<linux-arm-kernel@lists.infradead.org>,
	dl-linux-imx <linux-imx@nxp.com>
Subject: RE: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller RTC support
Date: Wed, 28 Nov 2018 09:21:56 +0000	[thread overview]
Message-ID: <DB3PR0402MB39168AC8DB69B81C51CE63C2F5D10@DB3PR0402MB3916.eurprd04.prod.outlook.com> (raw)
In-Reply-To: <20181128091943.GB8952@piout.net>

Best Regards!
Anson Huang

> -----Original Message-----
> From: Alexandre Belloni [mailto:alexandre.belloni@bootlin.com]
> Sent: 2018年11月28日 17:20
> To: Anson Huang <anson.huang@nxp.com>
> Cc: Lothar Waßmann <LW@KARO-electronics.de>; a.zummo@towertech.it;
> robh+dt@kernel.org; mark.rutland@arm.com; catalin.marinas@arm.com;
> will.deacon@arm.com; Aisheng DONG <aisheng.dong@nxp.com>; Andy Gross
> <andy.gross@linaro.org>; arnd@arndb.de; horms+renesas@verge.net.au;
> heiko@sntech.de; bjorn.andersson@linaro.org; enric.balletbo@collabora.com;
> amit.kucheria@linaro.org; ezequiel@collabora.com; olof@lixom.net;
> shawnguo@kernel.org; linux-rtc@vger.kernel.org; devicetree@vger.kernel.org;
> linux-kernel@vger.kernel.org; linux-arm-kernel@lists.infradead.org;
> dl-linux-imx <linux-imx@nxp.com>
> Subject: Re: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller
> RTC support
> 
> On 28/11/2018 09:06:27+0000, Anson Huang wrote:
> > > > 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..
> >
> 
> I guess the point is that you may not want it enabled, even if it should always
> be working. enabling it by default would affect the RTC ordering for example.

i.MX SoCs ONLY have 1 RTC. And RTC are always enabled by default for all i.MX
SoCs, so do we have to disable it here and enable it in board dts?

Anson.

> 
> 
> --
> Alexandre Belloni, Bootlin
> Embedded Linux and Kernel engineering
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