From mboxrd@z Thu Jan 1 00:00:00 1970 From: josephl@nvidia.com (Joseph Lo) Date: Mon, 29 Oct 2012 10:28:21 +0800 Subject: [PATCH 1/2] ARM: tegra: dt: add L2 cache controller In-Reply-To: <508AC294.7080506@wwwdotorg.org> References: <1351247649-15859-1-git-send-email-josephl@nvidia.com> <508AC294.7080506@wwwdotorg.org> Message-ID: <1351477701.2779.70.camel@jlo-ubuntu-64.nvidia.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Sat, 2012-10-27 at 01:04 +0800, Stephen Warren wrote: > On 10/26/2012 04:34 AM, Joseph Lo wrote: > > Add L2 cache controller binding into DT for Tegra. > > > diff --git a/arch/arm/boot/dts/tegra20.dtsi b/arch/arm/boot/dts/tegra20.dtsi > > > + L2: cache-controller at 50043000 { > > + compatible = "arm,pl310-cache"; > > + reg = <0x50043000 0x1000>; > > + arm,data-latency = <5 5 2>; > > + arm,tag-latency = <4 4 2>; > > + cache-unified; > > + cache-level = <2>; > > + }; > Stephen, Thanks for review. > Do you need to specify arm,filter-ranges here? It's certainly parsed by > pl310_of_setup() and used if present, although I don't think we're > programming the register in the existing code, so I guess we don't need it. > Yes, we don't need it. Because there are HW reset value for it. We don't need to configure it. > The L2 label above isn't necessary unless something references those > nodes. Usually, that something is the cpu nodes' next-level-cache > property. I don't suppose you could amend this series to also fill in > Tegra's /cpus nodes in these files too? OK. Will remove the label. > > Finally, is this series going to be a dependency for any of the cpuidle > or other work you're submitting? I assume it's completely independent > and hence I can throw it in any old branch in any order I feel like? No. We need this before the "powered-down" cpuidle support. Because the L2 init function didn't help to hook the resume API to "outer_cache_fns" interface currently. If we don't apply this before the "powered-down" cpuidle, we will lost L2 support after one successful powered-down cpuidle sequence. Thanks, Joseph