From mboxrd@z Thu Jan 1 00:00:00 1970 From: Heiko Stuebner Subject: Re: [PATCH v3 2/5] dt-bindings: soc: add document for rockchip reboot notifier driver Date: Thu, 19 Nov 2015 05:35:48 +0100 Message-ID: <2082288.pD4oKxtaXL@phil> References: <1447840044-19689-1-git-send-email-andy.yan@rock-chips.com> <20151118225904.GA5429@rob-hp-laptop> <564D2331.8070503@rock-chips.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <564D2331.8070503-TNX95d0MmH7DzftRWevZcw@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Andy Yan Cc: Rob Herring , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org, linux-rockchip-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, khilman-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org, treding-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org, wxt-TNX95d0MmH7DzftRWevZcw@public.gmane.org, sjg-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, benchan-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org List-Id: devicetree@vger.kernel.org Hi Andy, Am Donnerstag, 19. November 2015, 09:17:37 schrieb Andy Yan: > Hi Rob: >=20 > On 2015=E5=B9=B411=E6=9C=8819=E6=97=A5 06:59, Rob Herring wrote: > > On Wed, Nov 18, 2015 at 05:53:30PM +0800, Andy Yan wrote: > >> Add devicetree binding document for rockchip reboot nofifier drive= r > > Just reading the subject this is way too specific to the Linux driv= er > > needs rather than a h/w description. Please don't create fake DT no= des > > just to bind to drivers. Whatever &pmu is is probably what should h= ave > > the DT node. Let the driver for it create child devices if you need > > that. >=20 > This is note a fake DT nodes, we really need it to tell the driv= er > which register to use to store the reboot mode. Because rockchi= p > use different register file to store the reboot mode on differe= nt > platform, on rk3066,rk3188, rk3288,it use one of the PMU=20 > register, on > the incoming RK3036, it use one of the GRF register, and it use= =20 > one of > the PMUGRF register for arm64 platform rk3368. On the other han= d, the > PMU/GRF/PMUGRF register file are mapped as "syscon", then refer= enced > by other DT nodes by phandle. So maybe let it as a separate DT=20 > node here > is better. or alternatively we could do something similar to what the bl-switcher=20 cupfreq-driver does. Take a look at drivers/cpufreq/arm_big_little.c drivers/clk/clk-mb86s7x.c We already have the core restart-handler code in the clock-tree, so cou= ld=20 maybe simply do the platform_device_register_simple("rockchip-reboot", -1, NULL, 0); in that common code? Though I'm not yet sure how to get the platform-data. I guess one optio= n would=20 be to do things like the 3288 suspend code does (arch/arm/mach-rockchip= /pm.c=20 at the bottom), by having the per-soc-data in the driver and then match= ing=20 against the pmu. Because the pmu is not part of the clock controller bi= nding=20 (and probably also shouldn't be). Heiko -- To unsubscribe from this list: send the line "unsubscribe devicetree" i= n the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html