From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lorenzo Pieralisi Subject: Re: [RFC PATCH v2 0/1] ARM: cpuidle: heterogeneous systems extension Date: Thu, 30 Apr 2015 16:51:33 +0100 Message-ID: <20150430155133.GA9863@red-moon> References: <1429200617-9546-1-git-send-email-lorenzo.pieralisi@arm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1429200617-9546-1-git-send-email-lorenzo.pieralisi-5wv7dgnIgG8@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , "linux-pm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" Cc: Howard Chen , Rob Herring , Kevin Hilman , Sudeep Holla , Lina Iyer , Daniel Lezcano , "grant.likely-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org" , Mathieu Poirier , Mark Rutland List-Id: devicetree@vger.kernel.org On Thu, Apr 16, 2015 at 05:10:16PM +0100, Lorenzo Pieralisi wrote: > This patch is a v2 of a previous posting: > > http://lists.infradead.org/pipermail/linux-arm-kernel/2015-March/328192.html > > v1 -> v2: > > - Rebased against 4.0 > - Removed DT affinity probe interface > - Improved and optimized idle states comparison and cpumask creation > - Merged DT idle states vetting code in the ARM CPUidle driver > > This patch aims at enabling the generic CPUidle driver on ARM systems > with heterogeneous idle states. In the CPUidle context the kernel > considers cpus equal (and group them together through a CPUidle driver) > if they share the same set of idle states. > Since the idle states represent the differentiation point when it comes > to creating CPUidle drivers (their states and related cpu logical mask), > the idle states can be used as a means to create logical masks of cpus > for which the CPUidle driver applies. > > This patch sets the maximum number of static CPUidle drivers allowed to > two, since it is hard to foresee systems with more than two sets of CPUs > having different idle states; it is meant to keep allocation simple > while keeping functionality. > > The code carrying out idle states comparison is completely generic > and borrowed from OF unit tests; it overrides the OF API entirely > though to carry out properties (ie phandles list) comparison in the > fastest possible way. If deemed worthwhile it can be moved to generic OF > layer. > > Tested through several dts idle states permutations on Juno board with > CPUidle and related idle states enabled. Are there any comments/opinions on this patch ? Thanks, Lorenzo -- 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