From mboxrd@z Thu Jan 1 00:00:00 1970 From: lorenzo.pieralisi@arm.com (Lorenzo Pieralisi) Date: Thu, 30 Apr 2015 18:17:01 +0100 Subject: [PATCH] arm64: dts: Add idle-states for Juno In-Reply-To: <1430412035.2868.40.camel@linaro.org> References: <1430402268.2868.20.camel@linaro.org> <554251B4.2030808@arm.com> <1430412035.2868.40.camel@linaro.org> Message-ID: <20150430171701.GA31834@red-moon> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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. Lorenzo > > If we wait until ARM have finished tweaking their firmware and tuning > benchmark runs to get 'optimum' values for their main usecases then I > suspect we'll be waiting a long time ;-) > > -- > Tixy >