From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Thu, 30 Apr 2015 18:40:31 +0100 Subject: [PATCH] arm64: dts: Add idle-states for Juno In-Reply-To: <1430415404.2868.49.camel@linaro.org> References: <1430402268.2868.20.camel@linaro.org> <554251B4.2030808@arm.com> <1430412035.2868.40.camel@linaro.org> <20150430171701.GA31834@red-moon> <1430415404.2868.49.camel@linaro.org> Message-ID: <5542690F.5060001@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 30/04/15 18:36, Jon Medhurst (Tixy) wrote: > On Thu, 2015-04-30 at 18:17 +0100, Lorenzo Pieralisi wrote: >> On Thu, Apr 30, 2015 at 05:40:35PM +0100, Jon Medhurst (Tixy) wrote: >>> On Thu, 2015-04-30 at 17:00 +0100, Sudeep Holla wrote: >>>> >>>> On 30/04/15 14:57, Jon Medhurst (Tixy) wrote: >>>>> From: Jon Medhurst >>>>> >>>>> Signed-off-by: Jon Medhurst >>>>> --- >>>>> >>>>> These have been kicking around out of tree for ages, any reason they >>>>> shouldn't be in mainline? >>>> >>>> One possible reason could be that these values are not tuned(e.g. >>>> latency values, can they be same for both clusters ?) >>> >>> I thought that both clusters being the same was questionable. >>> >>>> Though these >>>> reasons are not blocking and this patch will not cause any >>>> functionality break even if is merged as is. >>> >>> My main purpose with trying to get this merged is so that people using >>> Juno for general testing and validation will actually have cpuidle >>> running and so potentially find more bugs. >> >> I am reluctant to enable idle states in the default Juno dts, they >> will affect latencies and performance tests significantly. I should >> find a way to disable them by default and possibly have a DT property >> to enabled them explicitly, we can't merge the dts as it is we have >> to change the CPUidle code first. > > Presumably the same argument goes for cpufreq? That'll upset people > doing performance benchmarks, so shouldn't be enabled by default? > Or we can have cpufreq enabled with performance governor as default ;) Regards, Sudeep