From patchwork Fri May 9 02:04:32 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiubo Li X-Patchwork-Id: 4140061 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id CD6B79F391 for ; Fri, 9 May 2014 02:54:17 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id EE99F202DD for ; Fri, 9 May 2014 02:54:16 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 3024F202EC for ; Fri, 9 May 2014 02:54:16 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Wiatt-0007cM-2i; Fri, 09 May 2014 02:51:05 +0000 Received: from mail-bn1blp0186.outbound.protection.outlook.com ([207.46.163.186] helo=na01-bn1-obe.outbound.protection.outlook.com) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Wiatj-0007Ss-Nb for linux-arm-kernel@lists.infradead.org; Fri, 09 May 2014 02:50:57 +0000 Received: from BY2PR03CA054.namprd03.prod.outlook.com (10.141.249.27) by BY2PR03MB506.namprd03.prod.outlook.com (10.141.143.18) with Microsoft SMTP Server (TLS) id 15.0.934.12; Fri, 9 May 2014 02:50:32 +0000 Received: from BN1AFFO11FD012.protection.gbl (2a01:111:f400:7c10::194) by BY2PR03CA054.outlook.office365.com (2a01:111:e400:2c5d::27) with Microsoft SMTP Server (TLS) id 15.0.939.12 via Frontend Transport; Fri, 9 May 2014 02:50:31 +0000 Received: from az84smr01.freescale.net (192.88.158.2) by BN1AFFO11FD012.mail.protection.outlook.com (10.58.52.72) with Microsoft SMTP Server (TLS) id 15.0.939.9 via Frontend Transport; Fri, 9 May 2014 02:50:31 +0000 Received: from rock.ap.freescale.net (rock.ap.freescale.net [10.193.20.106]) by az84smr01.freescale.net (8.14.3/8.14.0) with ESMTP id s492oGqR004875; Thu, 8 May 2014 19:50:26 -0700 From: Xiubo Li To: , , , , , , , , Subject: [PATCHv4 1/2] dt/bindings: Add the DT binding documentation for endianness Date: Fri, 9 May 2014 10:04:32 +0800 Message-ID: <1399601073-19278-2-git-send-email-Li.Xiubo@freescale.com> X-Mailer: git-send-email 1.8.0 In-Reply-To: <1399601073-19278-1-git-send-email-Li.Xiubo@freescale.com> References: <1399601073-19278-1-git-send-email-Li.Xiubo@freescale.com> X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:192.88.158.2; CTRY:US; IPV:NLI; EFV:NLI; SFV:NSPM; SFS:(10009001)(6009001)(189002)(199002)(77156001)(19580395003)(44976005)(20776003)(47776003)(6806004)(19580405001)(83322001)(68736004)(69596002)(64706001)(36756003)(80022001)(76482001)(46102001)(77982001)(21056001)(86362001)(93916002)(50226001)(4396001)(48376002)(74662001)(31966008)(74502001)(50466002)(87936001)(88136002)(87286001)(79102001)(83072002)(89996001)(92726001)(85852003)(2201001)(92566001)(76176999)(2009001)(99396002)(50986999)(77096999)(81542001)(62966002)(81342001); DIR:OUT; SFP:1101; SCL:1; SRVR:BY2PR03MB506; H:az84smr01.freescale.net; FPR:; MLV:sfv; PTR:InfoDomainNonexistent; MX:1; A:1; LANG:en; MIME-Version: 1.0 X-Forefront-PRVS: 02065A9E77 Received-SPF: Fail (: domain of freescale.com does not designate 192.88.158.2 as permitted sender) receiver=; client-ip=192.88.158.2; helo=az84smr01.freescale.net; Authentication-Results: spf=fail (sender IP is 192.88.158.2) smtp.mailfrom=Li.Xiubo@freescale.com; X-OriginatorOrg: freescale.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140508_195055_980850_15D6C0FF X-CRM114-Status: UNSURE ( 6.79 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -0.0 (/) Cc: devicetree@vger.kernel.org, Xiubo Li , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Device-Tree binding for device endianness The endianness mode of CPU & Device scenarios: Index CPU Device Endianness properties ------------------------------------------------------------ 1 LE LE - 2 LE BE 'big-endian{,-*}' 3 BE BE - 4 BE LE 'little-endian{,-*}' {big,little}-endian{,-*}: these are boolean properties, if absent meaning that the CPU and the Device are in the same endianness mode. Signed-off-by: Xiubo Li --- .../devicetree/bindings/endianness/endianness.txt | 48 ++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 Documentation/devicetree/bindings/endianness/endianness.txt diff --git a/Documentation/devicetree/bindings/endianness/endianness.txt b/Documentation/devicetree/bindings/endianness/endianness.txt new file mode 100644 index 0000000..cc5f7f8 --- /dev/null +++ b/Documentation/devicetree/bindings/endianness/endianness.txt @@ -0,0 +1,48 @@ +Device-Tree binding for device endianness + +The endianness mode of CPU & Device scenarios: +Index CPU Device Endianness properties +------------------------------------------------------------ +1 LE LE - +2 LE BE 'big-endian{,-*}' +3 BE BE - +4 BE LE 'little-endian{,-*}' + +For one device driver, which will run in different scenarios above +on different SoCs using the devicetree, we need one way to simplify +this. + +Required properties: +- {big,little}-endian{,-*}: these are boolean properties, if absent + meaning that the CPU and the Device are in the same endianness mode. + +Examples: +Scenario 1 : CPU in LE mode & device in LE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... +}; + +Scenario 2 : CPU in LE mode & device in BE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + big-endian{,-*}; +}; + +Scenario 3 : CPU in BE mode & device in BE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... +}; + +Scenario 4 : CPU in BE mode & device in LE mode. +dev: dev@40031000 { + compatible = "name"; + reg = <0x40031000 0x1000>; + ... + little-endian{,-*}; +};