Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752563AbaLDAsf (ORCPT ); Wed, 3 Dec 2014 19:48:35 -0500 Received: from mail-wg0-f41.google.com ([74.125.82.41]:44952 "EHLO mail-wg0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752442AbaLDAse (ORCPT ); Wed, 3 Dec 2014 19:48:34 -0500 From: Pali =?utf-8?q?Roh=C3=A1r?= To: Rob Herring Subject: Re: [PATCH] ARM: /proc/cpuinfo: Use DT machine name when possible Date: Thu, 4 Dec 2014 01:48:30 +0100 User-Agent: KMail/1.13.7 (Linux/3.18.0-031800rc5-generic; KDE/4.14.1; x86_64; ; ) Cc: Russell King , Santosh Shilimkar , Will Deacon , Ivaylo Dimitrov , Sebastian Reichel , Pavel Machek , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , Tony Lindgren References: <1403110464-29646-1-git-send-email-pali.rohar@gmail.com> <201411242319.27481@pali> In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart5274604.WHfR8KzK4F"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201412040148.31033@pali> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --nextPart5274604.WHfR8KzK4F Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Thursday 04 December 2014 01:33:08 Rob Herring wrote: > On Mon, Nov 24, 2014 at 4:19 PM, Pali Roh=C3=A1r=20 wrote: > > On Wednesday 18 June 2014 22:46:19 Rob Herring wrote: > >> On Wed, Jun 18, 2014 at 2:22 PM, Pali Roh=C3=A1r > >=20 > > wrote: > >> > On Wednesday 18 June 2014 21:07:35 Rob Herring wrote: > >> >> On Wed, Jun 18, 2014 at 11:54 AM, Pali Roh=C3=A1r > >> >=20 > >> > wrote: > >> >> > Machine name from board description is some generic > >> >> > name on DT kernel. DT provides machine name property > >> >> > which is specific for board, so use it instead > >> >> > generic one when possible. >=20 > [...] >=20 > >> > Basically in DT kernel is missing Hardware, Revision and > >> > probably also Serial key. (Now I used only qemu for > >> > testing which set serial key to 0). All these > >> > informations is used by userspace applications which > >> > determinate how to behave. > >>=20 > >> It is somewhat fragile to expect the name in the DT to > >> match the old name from the kernel. As your patch to n900 > >> dts shows, we'd probably have to update every dts file to > >> make them match. While I think we should work to remove > >> this string from the kernel, userspace depending on the DT > >> model string is a bad idea. For example, if you had some > >> platform with multiple OEMs just rebranding the same base > >> design, they may all want to put their own model string > >> into each product. The true h/w id is the compatible > >> string. > >>=20 > >> Serial number is easy. There is already a standard although > >> not widely used property for it with "/serial-number". You > >> just need to wire it up to cpuinfo. > >=20 > > There is no "/serial-number" property in kernel: > >=20 > > $ ls -l -a /sys/bus/soc/devices/soc0/ > > drwxr-xr-x 3 0 0 0 Jan 1 00:00 . > > drwxr-xr-x 18 0 0 0 Jan 1 00:00 .. > > -r--r--r-- 1 0 0 4096 Jan 1 00:00 > > family -r--r--r-- 1 0 0 4096 Jan 1 > > 00:00 machine drwxr-xr-x 2 0 0 0 > > Jan 1 00:00 power -r--r--r-- 1 0 0 =20 > > 4096 Jan 1 00:00 revision lrwxrwxrwx 1 0 0 =20 > > 0 Jan 1 00:00 subsystem -> ../../bus/soc > > -r--r--r-- 1 0 0 4096 Jan 1 00:00 > > type -rw-r--r-- 1 0 0 4096 Jan 1 > > 00:00 uevent >=20 > Wrong place. If you put /serial-number in your DT, then it > will be in /proc/device-tree/serial-number. >=20 > If you want to wire that up to /proc/cpuinfo, I would be fine > with that. >=20 > Rob I cannot hardcode it into DT, because it is set by bootloader.=20 And bootloader tell it to kernel via ATAGs structure. Bootloader=20 is closed and proprietary and cannot be replaced (there is no=20 documentation for hw init). =2D-=20 Pali Roh=C3=A1r pali.rohar@gmail.com --nextPart5274604.WHfR8KzK4F Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEABECAAYFAlR/r18ACgkQi/DJPQPkQ1JEtQCeNIcJKrrYy5hjLujXgyRSi6/l DyEAn2U36hPLd7/DiON+z7etlyxYw1kO =w8FE -----END PGP SIGNATURE----- --nextPart5274604.WHfR8KzK4F-- -- 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/