From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alexandre Belloni Subject: Re: [PATCH 4/4] ARM64: dts: imx: add i.MX8QXP system controller RTC support Date: Wed, 28 Nov 2018 10:58:23 +0100 Message-ID: <20181128095823.GE8952@piout.net> References: <1543311334-8807-1-git-send-email-Anson.Huang@nxp.com> <1543311334-8807-5-git-send-email-Anson.Huang@nxp.com> <20181128100420.0c9a721a@karo-electronics.de> <20181128091943.GB8952@piout.net> <20181128093345.GC8952@piout.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Anson Huang Cc: Lothar =?utf-8?B?V2Hvv73vv71tYW5u?= , "a.zummo@towertech.it" , "robh+dt@kernel.org" , "mark.rutland@arm.com" , "catalin.marinas@arm.com" , "will.deacon@arm.com" , Aisheng DONG , Andy Gross , "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" , shawn List-Id: devicetree@vger.kernel.org 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