From mboxrd@z Thu Jan 1 00:00:00 1970 From: punit.agrawal@arm.com (Punit Agrawal) Date: Thu, 15 Aug 2013 11:09:04 +0100 Subject: [PATCH] drivers: CCI: add ARM CCI PMU support In-Reply-To: References: <1374571176-11584-1-git-send-email-punit.agrawal@arm.com> <520BF152.1020704@wwwdotorg.org> <56FE58B8-1619-4CDF-A5E6-89CE6F51E96C@codeaurora.org> <520BF2E1.8070805@wwwdotorg.org> Message-ID: <520CA8C0.4080008@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 14/08/13 22:16, Kumar Gala wrote: > > On Aug 14, 2013, at 4:13 PM, Stephen Warren wrote: > >> On 08/14/2013 03:09 PM, Kumar Gala wrote: >>> >>> On Aug 14, 2013, at 4:06 PM, Stephen Warren wrote: >>> >>>> On 07/23/2013 03:19 AM, Punit Agrawal wrote: >>>>> The CCI PMU can profile bus transactions at the master and slave >>>>> interfaces of the CCI. The PMU can be used to observe an aggregated view >>>>> of the bus traffic between the various components connected to the CCI. >>>>> >>>>> Extend the existing CCI driver to support the PMU by registering a perf >>>>> backend for it. >>>>> >>>>> Document the device tree binding to describe the CCI PMU. >>>> >>>>> diff --git a/Documentation/devicetree/bindings/arm/cci.txt b/Documentation/devicetree/bindings/arm/cci.txt >>>> >>>>> + - CCI PMU node >>>>> + >>>>> + Node name must be "pmu". >>>> >>>> I don't think the binding should require the node to have a particular >>>> name; node names shouldn't be interpret/used/relied-upon by drivers. >>> >>> While I agree with that, we should be aiming for some convention and consistency with node names. >> >> Sure. Should there be a Documentation/devictree/bindings/node-names that >> lists common node names for people to use? Either way though, I still >> think this is an aspect of authoring the *.dts file, not an aspect of >> the DT binding? After all, what if there were more than one CCI so they >> needed to be named pmu at 0, pmu at 1, etc.? > > Agreed, I was thinking a bindings/node-names would be a good idea. > > I'm guessing 99% of people copy either from the example in the binding of an existing .dts file. So while I agree the binding shouldn't require a node name be a specific thing as part of the spec, we as reviewers should try to ensure consistency in examples or .dts files. > Based on the comments so far, I will change the bindings documentation submitted with this patch to remove the requirement for a particular node name for CCI PMU. As it is, this is not required by the driver but was only done for consistency. Cheers, Punit > - k >