From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751389AbdAPK7H (ORCPT ); Mon, 16 Jan 2017 05:59:07 -0500 Received: from foss.arm.com ([217.140.101.70]:49722 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750939AbdAPK7G (ORCPT ); Mon, 16 Jan 2017 05:59:06 -0500 Date: Mon, 16 Jan 2017 10:59:04 +0000 From: Will Deacon To: Mark Rutland Cc: linux-arm-kernel@lists.infradead.org, marc.zyngier@arm.com, kim.phillips@arm.com, alex.bennee@linaro.org, christoffer.dall@linaro.org, tglx@linutronix.de, peterz@infradead.org, alexander.shishkin@linux.intel.com, robh@kernel.org, suzuki.poulose@arm.com, pawel.moll@arm.com, mathieu.poirier@linaro.org, mingo@redhat.com, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH v2 10/10] dt-bindings: Document devicetree binding for ARM SPE Message-ID: <20170116105904.GB1510@arm.com> References: <1484323429-15231-1-git-send-email-will.deacon@arm.com> <1484323429-15231-11-git-send-email-will.deacon@arm.com> <20170113184352.GE2472@leverpostej> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170113184352.GE2472@leverpostej> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 13, 2017 at 06:43:52PM +0000, Mark Rutland wrote: > On Fri, Jan 13, 2017 at 04:03:49PM +0000, Will Deacon wrote: > > This patch documents the devicetree binding in use for ARM SPE. > > > > Cc: Mark Rutland > > Cc: Rob Herring > > Signed-off-by: Will Deacon > > --- > > Documentation/devicetree/bindings/arm/spe-pmu.txt | 20 ++++++++++++++++++++ > > 1 file changed, 20 insertions(+) > > create mode 100644 Documentation/devicetree/bindings/arm/spe-pmu.txt > > > > diff --git a/Documentation/devicetree/bindings/arm/spe-pmu.txt b/Documentation/devicetree/bindings/arm/spe-pmu.txt > > new file mode 100644 > > index 000000000000..d6540b491af4 > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/arm/spe-pmu.txt > > @@ -0,0 +1,20 @@ > > +* ARMv8.2 Statistical Profiling Extension (SPE) Performance Monitor Units (PMU) > > + > > +ARMv8.2 introduces the optional Statistical Profiling Extension for collecting > > +performance sample data using an in-memory trace buffer. > > + > > +** SPE Required properties: > > + > > +- compatible : should be one of: > > + "arm,arm-spe-pmu-v1" > > The second "arm" here doesn't seem to add much. Should that be "armv8.2" > instead? I don't think armv8.2 is particularly helpful, because that effectively ties together the SPE version and the architecture version, which I don't think is strictly required. The reason I added it was so that you could describe a partner implementation as something like: acme,arm-spe-pmu-v1 and know that it was acme's implementation of an ARM architectural feature. If I drop the second "arm", I was worried that it might conflict with other namespaces (e.g. acme's signal-processing-element's power-management-unit). What do you reckon? Will