Best Regards!
Anson Huang

-----Original Message-----
From: Alexandre Belloni [mailto:alexandre.belloni at bootlin.com]
Sent: 2018?11?28? 17:34
To: Anson Huang <redacted>
Cc: Lothar Wa??mann <redacted>; a.zummo at towertech.it;
robh+dt at kernel.org; mark.rutland at arm.com; catalin.marinas at arm.com;
will.deacon at arm.com; Aisheng DONG [off-list ref]; Andy Gross
[off-list ref]; arnd at arndb.de; horms+renesas at verge.net.au;
heiko at sntech.de; bjorn.andersson at linaro.org; enric.balletbo at collabora.com;
amit.kucheria at linaro.org; ezequiel at collabora.com; olof at lixom.net;
shawnguo at kernel.org; linux-rtc at vger.kernel.org; devicetree at vger.kernel.org;
linux-kernel at vger.kernel.org; linux-arm-kernel at lists.infradead.org;
dl-linux-imx [off-list ref]
Subject: Re: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller
RTC support

On 28/11/2018 09:21:56+0000, Anson Huang wrote:

quoted

quoted

quoted

This module is NOT depending on any board design, should it be
enabled by

default in soc dtsi?

quoted

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.

quoted

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.

Anson.

--
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
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