Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752689AbbKVUtm (ORCPT ); Sun, 22 Nov 2015 15:49:42 -0500 Received: from mail.kernel.org ([198.145.29.136]:36864 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752193AbbKVUtk (ORCPT ); Sun, 22 Nov 2015 15:49:40 -0500 Date: Sun, 22 Nov 2015 14:49:35 -0600 From: Rob Herring To: Stephen Boyd Cc: Andy Gross , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Olof Johansson , Kevin Hilman , Arnd Bergmann , devicetree@vger.kernel.org Subject: Re: [PATCH v2 1/5] devicetree: bindings: Document qcom board compatible format Message-ID: <20151122204935.GA465@rob-hp-laptop> References: <1448062280-15406-1-git-send-email-sboyd@codeaurora.org> <1448062280-15406-2-git-send-email-sboyd@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1448062280-15406-2-git-send-email-sboyd@codeaurora.org> 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 Content-Length: 3968 Lines: 103 On Fri, Nov 20, 2015 at 03:31:16PM -0800, Stephen Boyd wrote: > Some qcom based bootloaders identify the dtb blob based on a set > of device properties like SoC, platform, PMIC, and revisions of > those components. In downstream kernels, these values are added > to the different component dtsi files (i.e. pmic dtsi file, SoC > dtsi file, board dtsi file, etc.) via qcom specific DT > properties. The dtb files are parsed by a program called dtbTool > that picks out these properties and creates a table of contents > binary blob with the property information and some offsets into > the concatenation of all the dtbs (termed a QCDT image). > > The suggestion is to do this via the board compatible string > instead, because these qcom specific properties are never used by > the kernel. Add a document describing the format of the > compatible string that encodes all this information that's > currently encoded in the qcom,{msm-id,board-id,pmic-id} > properties in downstream devicetrees. Future bootloaders may be > updated to look at the compatible field instead of looking for > the table of contents image. For non-updateable bootloaders, a > new dtbTool program will parse the compatible string and generate > a QCDT image from it. > > Signed-off-by: Stephen Boyd Much more reasonable now. I do find the '/' in it a bit strange though. Acked-by: Rob Herring > --- > Documentation/devicetree/bindings/arm/qcom.txt | 51 ++++++++++++++++++++++++++ > 1 file changed, 51 insertions(+) > create mode 100644 Documentation/devicetree/bindings/arm/qcom.txt > > diff --git a/Documentation/devicetree/bindings/arm/qcom.txt b/Documentation/devicetree/bindings/arm/qcom.txt > new file mode 100644 > index 000000000000..3e24518c6678 > --- /dev/null > +++ b/Documentation/devicetree/bindings/arm/qcom.txt > @@ -0,0 +1,51 @@ > +QCOM device tree bindings > +------------------------- > + > +Some qcom based bootloaders identify the dtb blob based on a set of > +device properties like SoC and platform and revisions of those components. > +To support this scheme, we encode this information into the board compatible > +string. > + > +Each board must specify a top-level board compatible string with the following > +format: > + > + compatible = "qcom,[-][-]-[/][-]" > + > +The 'SoC' and 'board' elements are required. All other elements are optional. > + > +The 'SoC' element must be one of the following strings: > + > + apq8016 > + apq8074 > + apq8084 > + apq8096 > + msm8916 > + msm8974 > + msm8996 > + > +The 'board' element must be one of the following strings: > + > + cdp > + liquid > + dragonboard > + mtp > + sbc > + > +The 'soc_version' and 'board_version' elements take the form of v. > +where the minor number may be omitted when it's zero, i.e. v1.0 is the same > +as v1. If all versions of the 'board_version' elements match, then a > +wildcard '*' should be used, e.g. 'v*'. > + > +The 'foundry_id' and 'subtype' elements are one or more digits from 0 to 9. > + > +Examples: > + > + "qcom,msm8916-v1-cdp-pm8916-v2.1" > + > +A CDP board with an msm8916 SoC, version 1 paired with a pm8916 PMIC of version > +2.1. > + > + "qcom,apq8074-v2.0-2-dragonboard/1-v0.1" > + > +A dragonboard board v0.1 of subtype 1 with an apq8074 SoC version 2, made in > +foundry 2. > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > a Linux Foundation Collaborative Project > > -- > To unsubscribe from this list: send the line "unsubscribe devicetree" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/