From owner-freebsd-arm@FreeBSD.ORG Thu Feb 14 06:53:45 2013 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 7F24C841 for ; Thu, 14 Feb 2013 06:53:45 +0000 (UTC) (envelope-from imp@bsdimp.com) Received: from mail-ob0-f180.google.com (mail-ob0-f180.google.com [209.85.214.180]) by mx1.freebsd.org (Postfix) with ESMTP id 0E62395A for ; Thu, 14 Feb 2013 06:53:44 +0000 (UTC) Received: by mail-ob0-f180.google.com with SMTP id ef5so2070218obb.25 for ; Wed, 13 Feb 2013 22:53:44 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-received:sender:subject:mime-version:content-type:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to:x-mailer:x-gm-message-state; bh=hnE//LUpQve8fTjis5LRLNE71Ey53AE4GRHD0iFaw3s=; b=aao18XIaq+ETc0RC/DgyyDaCQoBfOZAtnXQ5BfpqbcFvGFLXs+SSce4NWYaNn5l+u3 0Zb3w46WUz4dUWi7rFJP6AHIu/d4UUhzCxBJFFnECMq9rkmz+BsJB4wegmE0cA7+3W7v 4HlYvYyzllnWe9YgaKT9AWttpTOl32W3s8kzZ0cZoO4vpwiwvorXI2XQTQkRachGkbe5 0nZSlPjXL9n9qpwZA7JI95tzXohLqA8JOqXUj72sCGsrnbJ3jeYRnowYf3l/69/0xeLq i5l/E+tQ/5IRMKSHcEeJJv84CC7xPJHOgm7sHJux50l9WWFsB9sHLoNZd6Vr4pnq75nk eMiA== X-Received: by 10.182.167.70 with SMTP id zm6mr18904711obb.93.1360824823974; Wed, 13 Feb 2013 22:53:43 -0800 (PST) Received: from 53.imp.bsdimp.com ([209.117.142.2]) by mx.google.com with ESMTPS id v2sm59934398obl.10.2013.02.13.22.53.39 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 13 Feb 2013 22:53:43 -0800 (PST) Sender: Warner Losh Subject: Re: building RaspPi Images Mime-Version: 1.0 (Apple Message framework v1085) Content-Type: text/plain; charset=windows-1252 From: Warner Losh In-Reply-To: <8FD7D8A3-A1FB-4499-A411-7CEF91387FF8@freebsd.org> Date: Wed, 13 Feb 2013 23:53:37 -0700 Content-Transfer-Encoding: quoted-printable Message-Id: <4EC0D89B-3B17-4650-BCCF-8CA0B83E746E@bsdimp.com> References: <5116CB50.9080303@ceetonetechnology.com> <7757848F-45C6-4DEF-A4A2-5F900EB10A06@kientzle.com> <20130210012052.4d7e1a46@ivory.local> <58DCA6BE-8C06-4F69-81A2-A3582FBB5B12@kientzle.com> <1360598511.4545.92.camel@revolution.hippie.lan> <1360600007.4545.98.camel@revolution.hippie.lan> <3F4CD7E5-17D4-4315-86BD-605F5C0040DC@kientzle.com> <1360604561.4545.115.camel@revolution.hippie.lan> <72554169-D2DD-48DD-8C2F-6C411DBFCE4D@kientzle.com> <25EAEA1F-876A-4189-BCD4-A7D438332C11@kientzle.com> <5F763292-2EA4-426A-B84A-8DE533BA6308@bsdimp.com> <20ABD94C-206C-4936-BAE7-88D379F27B74@bsdimp.com> <8FD7D8A3-A1FB-4499-A411-7CEF91387FF8@freebsd.org> To: Tim Kientzle X-Mailer: Apple Mail (2.1085) X-Gm-Message-State: ALoCoQl8MKNQkOtDgVFCuwj17VQQwN9fadsaqBWxY5ux/21ftaioeA3Bq2M4V1xeyDkK1570Pzmo Cc: freebsd-arm@freebsd.org X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Porting FreeBSD to the StrongARM Processor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 14 Feb 2013 06:53:45 -0000 On Feb 13, 2013, at 10:35 PM, Tim Kientzle wrote: >=20 > On Feb 12, 2013, at 10:17 PM, Warner Losh wrote: >=20 >>=20 >> On Feb 12, 2013, at 10:30 PM, Tim Kientzle wrote: >>=20 >>> On Feb 12, 2013, at 10:45 AM, Warner Losh wrote: >>>=20 >>>> But it doesn't have all the pin group stuff in yet, so I'll have to = chase that down and see what happened to that part of the early patches = I was reviewing=85 >>>=20 >>> I would be interested in seeing those early patches. >>>=20 >>> I agree that it would be best to bundle pinmux info >>> with the related device in the FDT. Seeing some >>> prior art would help a lot. >>=20 >> They were posted to the device-tree mailing list a while ago, but I = don't have a pointer to the archives :(... They were from somebody at = Atmel.com, so if you find it, it will be easy to search for. >>=20 >> Warner >>=20 >=20 >=20 > I finally found the thread I think you're referring to, from > January 2012. This looks like an interesting post > because it gives some concrete ideas for what the > device tree might look like (and the author gives > some thoughtful critiques that I'll have to think about > further): >=20 > = https://lists.ozlabs.org/pipermail/devicetree-discuss/2012-January/012015.= html >=20 > Skimming some other discussions, it looks like the general > idea a lot of folks are considering is: >=20 > Having a pinmux node for whatever hardware controls > pinmuxing. For the TI chip I'm working with, that would be > the scm (System Control Module). >=20 > Within that node, have a collection of named pinmux settings. > E.g., pmx_ethernet01 or pmx_uart02 >=20 > Within other hardware nodes, refer to those named > settings, so you might have (very roughly; I still don't > understand FDT syntax): >=20 > uart02: uart@40800000 { > compatible =3D "=85."; > =85. > pinmux =3D "pmx_uart02"; > pinmuxc =3D "scm01"; > } >=20 > (That is, the uart02 should use scm01 to enable > pmx_uart02 pinmux settings.) In particular, for > hardware with multiple states, you could refer > to multiple pinmux settings (e.g., an idle setting > that tristated the outputs vs. an active setting > that powered them). >=20 > A lot of the debate seems to revolve around the details > of whether the pinmux details should be lists of hardware > numeric codes (advantage: eliminates tables from > the pinmux driver source and eliminates lots of text > from the DTS) or should be more verbose textual > descriptions (advantage: easier to read and update). >=20 > Is this generally what you had in mind? Generally, yes. The thread I had seen was a different one, but one quite = similar in tone.... Warner