From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757518AbeAHQgK (ORCPT + 1 other); Mon, 8 Jan 2018 11:36:10 -0500 Received: from heliosphere.sirena.org.uk ([172.104.155.198]:57452 "EHLO heliosphere.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756153AbeAHQgI (ORCPT ); Mon, 8 Jan 2018 11:36:08 -0500 Date: Mon, 8 Jan 2018 16:36:06 +0000 From: Mark Brown To: "Andrew F. Davis" Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] regcache: flat: Add valid bit to this cache type Message-ID: <20180108163606.GH11698@sirena.org.uk> References: <20180107232234.11064-1-afd@ti.com> <20180107232234.11064-3-afd@ti.com> <20180108120801.GD11698@sirena.org.uk> <4daf0acd-2d50-5873-212e-618e7b6d8123@ti.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="CEUtFxTsmBsHRLs3" Content-Disposition: inline In-Reply-To: <4daf0acd-2d50-5873-212e-618e7b6d8123@ti.com> X-Cookie: We are what we are. User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: --CEUtFxTsmBsHRLs3 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Mon, Jan 08, 2018 at 10:25:28AM -0600, Andrew F. Davis wrote: > I can understand the need for a fast cache type, but without this change > the implementation is simply wrong IMHO. Reading from a register that > has not been read/written to should not just assume the default value is > 0, it should first read and load the real initial value into the cache, > just like other cache types do. Users are supposed to ensure that the cache is fully initialized either by supplying defaults or writing to all the registers. Adding reads is problematic since we'd suddenly start reading from hardware which might not like it. > Also, it looks like this cache type is used mostly in I2C devices > (outside of sound/soc/, where in there, like you said MMIO devices are > more common). Sounds like a good thing to do an audit and contribute fixes for... --CEUtFxTsmBsHRLs3 Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAlpTnfUACgkQJNaLcl1U h9DH/Qf/QzHb4duX/VVgYqh1QPjFLifHFQDjs/3GYg07w/Smqtodc7NqLJDBQpXM SsKOjWKYX1DdNHw/xjJzoCFOSlxYPcv8HGKdRrLivRI93stIS2qdxJB+sKEQB5nP E3bcR8sgGnhFLw0vPu0M39uPUzVWrqdKVzB+QPUZolle96nHBJ9962VgBLEsfKx2 4x3DfIM3ziRGDOwPEvE4fZDfG5hDvaQy/ugNe527Cj0Ru2O3AfwMrYM21Xq8v+ix YYdP0+CSNeUnA3IbTDUxJE+eWZwc+7REXVxaKpCiuewUKDVt7BSeuYsLTwDdLSBS 7Yh6CuyzDAZBrggPsV5bFT+okuvFdA== =GnjO -----END PGP SIGNATURE----- --CEUtFxTsmBsHRLs3--