From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753203AbbBSSNV (ORCPT ); Thu, 19 Feb 2015 13:13:21 -0500 Received: from [212.85.155.42] ([212.85.155.42]:52553 "EHLO atreides.gradator.net" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752449AbbBSSNT (ORCPT ); Thu, 19 Feb 2015 13:13:19 -0500 Date: Thu, 19 Feb 2015 19:12:18 +0100 From: Sylvain Rochet To: Maxime Bizon Cc: Pantelis Antoniou , Mark Rutland , "devicetree@vger.kernel.org" , Tony Lindgren , Koen Kooi , Nicolas Ferre , "linux-kernel@vger.kernel.org" , Grant Likely , Ludovic Desroches , "linux-arm-kernel@lists.infradead.org" , Matt Porter , frowand.list@gmail.com, Guenter Roeck Message-ID: <20150219181218.GA5048@gradator.net> References: <1424271576-1952-3-git-send-email-pantelis.antoniou@konsulko.com> <20150218154106.GC29429@leverpostej> <20150218173115.GG29429@leverpostej> <76BD1B22-BAED-4205-9B34-186907CE0217@konsulko.com> <54E613E7.2020405@gmail.com> <670D0881-DBF0-45E8-A502-A6DB2B77A750@konsulko.com> <54E61DD2.3060002@gmail.com> <53F2F94C-0C43-4A54-B8CD-EEC454A0AC19@konsulko.com> <1424368919.13604.9.camel@sakura.staff.proxad.net> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ikeVEW9yuYc//A+q" Content-Disposition: inline In-Reply-To: <1424368919.13604.9.camel@sakura.staff.proxad.net> User-Agent: Mutt/1.5.21 (2010-09-15) X-SA-Exim-Connect-IP: X-SA-Exim-Mail-From: gradator@atreides.gradator.net Subject: Re: [PATCH 2/4] of: DT quirks infrastructure X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on atreides.gradator.net) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --ikeVEW9yuYc//A+q Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Thu, Feb 19, 2015 at 07:01:59PM +0100, Maxime Bizon wrote: > On Thu, 2015-02-19 at 19:38 +0200, Pantelis Antoniou wrote: >=20 > > Having to boot and tweak the bootloader settings to select the correct > > dtb (even if it=E2=80=99s present on the flash medium) takes time and is > > error-prone. >=20 > Dedicate a set of GPIO for board/PCB revision detection (it only costs a > few resistors connected to VCC or GND), then use that information to > choose the correct DTB. Or use a 1-wire or I2C EEPROM to store your board information. Or, even better, if you have an I2C device, just chose a different=20 address on each board for this device and then probe I2C devices in your=20 boot loader until you found one you are looking for, this way, you don't=20 need spare GPIO at all. You don't even need to populate the same I2C=20 device on all boards, you can actually probe anything. Sylvain --ikeVEW9yuYc//A+q Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlTmJ4IACgkQDFub3qtEsS80mwCfevIvIuQtD5uKbP+9T08R7KQN X94An36Sviep4vYhaI30ufjuOuG5mY2V =2kNf -----END PGP SIGNATURE----- --ikeVEW9yuYc//A+q-- From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sylvain Rochet Subject: Re: [PATCH 2/4] of: DT quirks infrastructure Date: Thu, 19 Feb 2015 19:12:18 +0100 Message-ID: <20150219181218.GA5048@gradator.net> References: <1424271576-1952-3-git-send-email-pantelis.antoniou@konsulko.com> <20150218154106.GC29429@leverpostej> <20150218173115.GG29429@leverpostej> <76BD1B22-BAED-4205-9B34-186907CE0217@konsulko.com> <54E613E7.2020405@gmail.com> <670D0881-DBF0-45E8-A502-A6DB2B77A750@konsulko.com> <54E61DD2.3060002@gmail.com> <53F2F94C-0C43-4A54-B8CD-EEC454A0AC19@konsulko.com> <1424368919.13604.9.camel@sakura.staff.proxad.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="ikeVEW9yuYc//A+q" Return-path: Content-Disposition: inline In-Reply-To: <1424368919.13604.9.camel-MdnFuL0m/hCw+z8RR+d9WEZ2mhrpEnA6@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Maxime Bizon Cc: Pantelis Antoniou , Mark Rutland , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Tony Lindgren , Koen Kooi , Nicolas Ferre , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Grant Likely , Ludovic Desroches , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" , Matt Porter , frowand.list-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, Guenter Roeck List-Id: devicetree@vger.kernel.org --ikeVEW9yuYc//A+q Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Hello, On Thu, Feb 19, 2015 at 07:01:59PM +0100, Maxime Bizon wrote: > On Thu, 2015-02-19 at 19:38 +0200, Pantelis Antoniou wrote: >=20 > > Having to boot and tweak the bootloader settings to select the correct > > dtb (even if it=E2=80=99s present on the flash medium) takes time and is > > error-prone. >=20 > Dedicate a set of GPIO for board/PCB revision detection (it only costs a > few resistors connected to VCC or GND), then use that information to > choose the correct DTB. Or use a 1-wire or I2C EEPROM to store your board information. Or, even better, if you have an I2C device, just chose a different=20 address on each board for this device and then probe I2C devices in your=20 boot loader until you found one you are looking for, this way, you don't=20 need spare GPIO at all. You don't even need to populate the same I2C=20 device on all boards, you can actually probe anything. Sylvain --ikeVEW9yuYc//A+q Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlTmJ4IACgkQDFub3qtEsS80mwCfevIvIuQtD5uKbP+9T08R7KQN X94An36Sviep4vYhaI30ufjuOuG5mY2V =2kNf -----END PGP SIGNATURE----- --ikeVEW9yuYc//A+q-- -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 From: gradator@gradator.net (Sylvain Rochet) Date: Thu, 19 Feb 2015 19:12:18 +0100 Subject: [PATCH 2/4] of: DT quirks infrastructure In-Reply-To: <1424368919.13604.9.camel@sakura.staff.proxad.net> References: <1424271576-1952-3-git-send-email-pantelis.antoniou@konsulko.com> <20150218154106.GC29429@leverpostej> <20150218173115.GG29429@leverpostej> <76BD1B22-BAED-4205-9B34-186907CE0217@konsulko.com> <54E613E7.2020405@gmail.com> <670D0881-DBF0-45E8-A502-A6DB2B77A750@konsulko.com> <54E61DD2.3060002@gmail.com> <53F2F94C-0C43-4A54-B8CD-EEC454A0AC19@konsulko.com> <1424368919.13604.9.camel@sakura.staff.proxad.net> Message-ID: <20150219181218.GA5048@gradator.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hello, On Thu, Feb 19, 2015 at 07:01:59PM +0100, Maxime Bizon wrote: > On Thu, 2015-02-19 at 19:38 +0200, Pantelis Antoniou wrote: > > > Having to boot and tweak the bootloader settings to select the correct > > dtb (even if it?s present on the flash medium) takes time and is > > error-prone. > > Dedicate a set of GPIO for board/PCB revision detection (it only costs a > few resistors connected to VCC or GND), then use that information to > choose the correct DTB. Or use a 1-wire or I2C EEPROM to store your board information. Or, even better, if you have an I2C device, just chose a different address on each board for this device and then probe I2C devices in your boot loader until you found one you are looking for, this way, you don't need spare GPIO at all. You don't even need to populate the same I2C device on all boards, you can actually probe anything. Sylvain -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 198 bytes Desc: Digital signature URL: