From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jassi Brar Subject: Re: [PATCH 3/4] clk: Provide always-on clock support Date: Sat, 28 Feb 2015 14:51:17 +0530 Message-ID: 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 Return-path: In-Reply-To: <1425071674-16995-4-git-send-email-lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lee Jones 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 28 February 2015 at 02:44, Lee Jones wrote: > Lots of platforms contain clocks which if turned off would prove fatal. > The only way to recover from these catastrophic failures is to restart > the board(s). Now, when a clock is registered with the framework it is > compared against a list of provided always-on clock names which must be > kept ungated. If it matches, we enable the existing CLK_IGNORE_UNUSED > flag, which will prevent the common clk framework from attempting to > 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. 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? -Jassi -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html