Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755430AbaDPKNv (ORCPT ); Wed, 16 Apr 2014 06:13:51 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:34812 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755214AbaDPKNp (ORCPT ); Wed, 16 Apr 2014 06:13:45 -0400 Date: Wed, 16 Apr 2014 11:13:23 +0100 From: Mark Brown To: Lee Jones Cc: Doug Anderson , Anton Vorontsov , Olof Johansson , Sachin Kamat , ajaykumar.rs@samsung.com, linux-samsung-soc@vger.kernel.org, Samuel Ortiz , linux-kernel@vger.kernel.org Message-ID: <20140416101323.GP12304@sirena.org.uk> References: <1397592876-5741-1-git-send-email-dianders@chromium.org> <1397592876-5741-3-git-send-email-dianders@chromium.org> <20140416095922.GG4754@lee--X1> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/F2XdnRjS8y2HUtp" Content-Disposition: inline In-Reply-To: <20140416095922.GG4754@lee--X1> X-Cookie: You will be successful in your work. User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH 2/3] mfd: tps65090: Stop caching registers X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --/F2XdnRjS8y2HUtp Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Apr 16, 2014 at 10:59:22AM +0100, Lee Jones wrote: > > NOTE: the IRQnMASK and CG_CTRLn registers are the exception and could > > be cached. If we find that we spend a lot of time reading those we > > can turn on cache for just those registers. > > -static bool is_volatile_reg(struct device *dev, unsigned int reg) > > -{ > > - if ((reg == TPS65090_INT_STS) || (reg == TPS65090_INT_STS2)) > > - return true; > > - else > > - return false; > > -} > > - > I don't know enough about Regmap internals to know what this actually > affects in real terms. > Mark, > Does this change seem sane to you? It does what it says, it stops us caching stuff. It would seem better to do what the changelog suggests above and keep caching the registers that can be cached - especially the interrupt masks, they should get read in the interrupt path and that tends to be a bit latency sensitive. --/F2XdnRjS8y2HUtp Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAgAGBQJTTlfAAAoJELSic+t+oim9XG0P/0GYEXL3COJuPxqh4msPQdvE kGpJmlst0l7U6EU3MVJT3VTqCv6ZuXhxiklxyZYI4CckicqcR2/ob6YiMrcUN9km FoFclt5EDxWzLAz7GvvxjCNHfllFnju80CSMr9RQD91sWp7Wo5+XyKwRu3t312lk N50sFcSmk/arIdp6NvQiMXATFjilq13rlfKtKVisIEj92E4DZTgQ3qePl+9USv8K vMIijoBMIMZyN7ieKDynXUuPNKfykhkkxSR3qBGqeG9x+Uq7rl3sq/4SmVNxo8jx gLANJ/QXbc7R4lvZcF+xhJiHikl+TQY2A757Kvdmeg/N9YmpvNU2KgLr/ODvqoOk lzj6J3Rvxmf60ocipoQtzln6A6R3EQDyFKlWsdxyAalBotXSmwK2YLxf5Ypgl8Ye CCSWGk+WSGwUwiYA5e50O8KICbv55C9YLIe35XdSUT91thEFendF7eevRbyP/jmR PkS/kcVii4NkLmmk46COre7TO5bxXJYwp1grrfTmuluZXWOPSCSjs2t+33sbM2Bt xbX08biXZJaZjLfPUOvDK2lV6ivLhWYqoepzl6G48qsd6UUUNcemsPjHvNov2eEH 1v9A0bQ3GDkso7NbEPvhhdjxawbx/VN0cPQc127rnY6l6S/ceNPAfCUFxKK9sai+ aJydW/fwYzo5qXPnTDqG =kwAY -----END PGP SIGNATURE----- --/F2XdnRjS8y2HUtp-- -- 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/