Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754869AbaAFOz5 (ORCPT ); Mon, 6 Jan 2014 09:55:57 -0500 Received: from comal.ext.ti.com ([198.47.26.152]:44212 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754093AbaAFOzz (ORCPT ); Mon, 6 Jan 2014 09:55:55 -0500 Message-ID: <52CAC3AF.9020401@ti.com> Date: Mon, 6 Jan 2014 10:54:39 -0400 From: Eduardo Valentin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130510 Thunderbird/17.0.6 MIME-Version: 1.0 To: Mark Rutland CC: Matthew Longnecker , Wei Ni , Eduardo Valentin , "swarren@wwwdotorg.org" , Pawel Moll , "ian.campbell@citrix.com" , "rob.herring@calxeda.com" , "linux@roeck-us.net" , "rui.zhang@intel.com" , "grant.likely@linaro.org" , "durgadoss.r@intel.com" , "linux-pm@vger.kernel.org" , "devicetree@vger.kernel.org" , "lm-sensors@lm-sensors.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCHv9 02/20] thermal: introduce device tree parser References: <1384285582-16933-1-git-send-email-eduardo.valentin@ti.com> <1384285582-16933-3-git-send-email-eduardo.valentin@ti.com> <52C4D612.2090808@nvidia.com> <52C5A6CE.5060904@nvidia.com> <20140106135145.GD21906@e106331-lin.cambridge.arm.com> In-Reply-To: <20140106135145.GD21906@e106331-lin.cambridge.arm.com> X-Enigmail-Version: 1.6 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="HemHAM6TDENViXwlV0JfG3QCrj3ptvQ4w" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --HemHAM6TDENViXwlV0JfG3QCrj3ptvQ4w Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable On 06-01-2014 09:51, Mark Rutland wrote: > On Thu, Jan 02, 2014 at 05:50:06PM +0000, Matthew Longnecker wrote: >> >>> I think the platform driver may set governor for the thermal zone, >>> so how about to add a property named as "governor", >>> and parse it to tzp->governor_name, >>> something like: >>> ret =3D of_property_read_string(child, "governor", &= str); >>> if (ret =3D=3D 0) >>> if (strlen(str) < THERMAL_NAME_LENGTH) >>> strcpy(tzp->governor_name, str); >>> >>> Thanks. >>> Wei. >> >> DT is supposed to describe the hardware, right? The governor isn't=20 >> hardware -- it's a software control policy. On the other hand, that=20 >> control policy must be tuned according to the behaviors of the platfor= m=20 >> hardware otherwise the system will be unstable. >> >> Is it appropriate to be naming the governor in DT? If so, is it equall= y=20 >> appropriate to describe any governor-specific parameters in DT (even=20 >> though they are pure software constructs)? >=20 > The dt should be relatively static -- if the hardware doesn't change th= e > dt shouldn't have to. >=20 > The governers are not static. We can introduce new ones and throw away > old ones at any time. Tuning parameters can also change at any time. >=20 > I'd prefer to not have governer details described in the dt, and the > choice of governer and configuration of its tuning parameters should be= > made at runtime somehow. Agreed. >=20 > Thanks, > Mark. >=20 >=20 --=20 You have got to be excited about what you are doing. (L. Lamport) Eduardo Valentin --HemHAM6TDENViXwlV0JfG3QCrj3ptvQ4w Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iF4EAREIAAYFAlLKw68ACgkQCXcVR3XQvP0v5AD/U+wQ8Mvydjvc9EysY14REF44 KKKk8WVNU19Isgnw22oA/j7sBLySG7jp7kbNwn1NF32olLyIT+0GD6Jicf3Igv31 =L2Gl -----END PGP SIGNATURE----- --HemHAM6TDENViXwlV0JfG3QCrj3ptvQ4w-- -- 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/