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Date:   Wed, 28 Nov 2018 10:58:23 +0100
From:   Alexandre Belloni <alexandre.belloni@bootlin.com>
To:     Anson Huang <anson.huang@nxp.com>
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Subject: Re: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller RTC
 support
Message-ID: <20181128095823.GE8952@piout.net>
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On 28/11/2018 09:41:22+0000, Anson Huang wrote:
> > > 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?
> > >
> > 
> > I would say that most of the i.MX based boards include another RTC because
> > the SoC one consumes way too much power.
> > 
> > Note that I don't care too much whether it is enabled by default, I was simply
> > explaining why you may want to disable it by default.
> 
> OK, this system controller RTC is a little different, it is controlled by system controller firmware,
> and system controller firmware will always select the best one for its user(Linux kernel) if there are other
> RTCs available, so I think we can keep it enabled by default for now. Thanks.
> 

Do you mean that the plan is to push support for the external RTCs (e.g.
the i2c ones) to the M4 firmware?

-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com