From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lee Jones Subject: Re: [PATCH 3/4] clk: Provide always-on clock support Date: Mon, 2 Mar 2015 08:36:52 +0000 Message-ID: <20150302083652.GE31325@x1> References: <1425071674-16995-1-git-send-email-lee.jones@linaro.org> <1425071674-16995-4-git-send-email-lee.jones@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jassi Brar Cc: "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , lkml , Mike Turquette , sboyd-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, kernel-F5mvAk5X5gdBDgjK7y7TUQ@public.gmane.org, Devicetree List List-Id: devicetree@vger.kernel.org On Sat, 28 Feb 2015, Jassi Brar wrote: > On 28 February 2015 at 02:44, Lee Jones wrote: > > Lots of platforms contain clocks which if turned off would prove fa= tal. > > The only way to recover from these catastrophic failures is to rest= art > > the board(s). Now, when a clock is registered with the framework i= t is > > compared against a list of provided always-on clock names which mus= t be > > kept ungated. If it matches, we enable the existing CLK_IGNORE_UNU= SED > > flag, which will prevent the common clk framework from attempting t= o > > gate it during the clk_disable_unused() procedure. > > > If a clock is critical on a certain board, it could be got+enabled > during early boot so there is always a user. I tried this. There was push-back from the DT maintainers. http://lists.infradead.org/pipermail/linux-arm-kernel/2015-February/3= 24417.html > To be able to do that from DT, maybe add a new, say, CLK_ALWAYS_ON > flag could be made to initialize the clock with one phantom user > already. Or just reuse the CLK_IGNORE_UNUSED? How is that different to what this set is doing? --=20 Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org =E2=94=82 Open source software for ARM SoCs =46ollow Linaro: Facebook | Twitter | Blog -- 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