From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sebastian Reichel Subject: Re: ARM errata 430973 on multi platform kernels Date: Tue, 7 Apr 2015 05:12:33 +0200 Message-ID: <20150407031233.GA16189@earth> References: <5520E2EE.4080302@gmail.com> <5521A438.1070008@gmail.com> <20150406151939.GG18048@atomide.com> <20150406154037.GI18048@atomide.com> <5522BEEF.2000405@gmail.com> <20150406174245.GJ18048@atomide.com> <20150407022312.GK18048@atomide.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="cNdxnHkX5QqsyA0e" Return-path: Received: from mail.kernel.org ([198.145.29.136]:34373 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752688AbbDGDNE (ORCPT ); Mon, 6 Apr 2015 23:13:04 -0400 Content-Disposition: inline In-Reply-To: <20150407022312.GK18048@atomide.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: Tony Lindgren Cc: Matthijs van Duin , Ivaylo Dimitrov , "linux-arm-kernel@lists.infradead.org" , "linux-omap@vger.kernel.org" , Pavel Machek --cNdxnHkX5QqsyA0e Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi, On Mon, Apr 06, 2015 at 07:23:13PM -0700, Tony Lindgren wrote: > I'm now thinking the kernel should just always set the 430973 specific > cpu_v7_switch_mm for all cortex-a8 if IBE bit is set. That avoids > the whole mess of early SoC detection and smc calls. And if IBE bit > is not set, then we just use the regular cpu_v7_switch_mm. > > This will work as long as we can read the aux ctrl register IBE > bit using mrc, which I believe is the case for all cortex-a8 based > omap variants. If I understood it correctly we can simply call the BTB flush on cortex-a8 if IBE bit is not set, since it would be translated as nop. So it should be safe to include the call on all cortex-a8 based cpus. We may need a non-BTB-flushing function for non-cortex-a8 based cpus, though. -- Sebastian --cNdxnHkX5QqsyA0e Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBCgAGBQJVI0seAAoJENju1/PIO/qa8NAP/iPMTvtOPWt4zTWItMZIJDKA 1kjwMMAm+lqDd9s68ZXkKIseQqHSqFVm+UonLoQ4yQ7pyUs7MjY+ld/XXAH+FFpY 4OIIgjdstUP6hKd1qnyZBcoVb/+QCxDVbJjxSaHrKgGI47x8LzGcZ/4kdMceIaOw PuQB9V3wbjQBbPMv49euzpQU95dUYhajzEhkIqqDufEurlmbdFdcgalvzXmdICAS 2+RgCoF7IwRB97EBjZ0g/i5HvRDY3hb/kdyWHcEDXdnA4c1YnqU/5XGU8KixUizW iM6sd9JxXBQT1QG7M4JYbVCK12TYrRw4aBc3bDLWKw7y3btyDQSW7InVdkmJFmAz wyj9jX/z4uhkReAECwlZ0sm7MDxIMQn3dSU5CPggmdtqDPZ4cMfWPIDAiTm+1Mse lMjFrqwNYj5qX3iiArf6olHp7t76D/eB6N6HqyNjrsHaHuJzzhFp6wJfOmfMODUN rOrKHTLP8UpdEI805VvyWTRGbT3GIWX376dRi45UMbOmJFy7HpZxrIKs2yN1vsPV 2ltArHarV77fbGd5YUuSC/C6trOQ/x4fBrxV+fyMuNH5w+UYLrhmKEwFZXzQ+QqC Aad1f5h6PpTQsOD1wMzkzMezOikfw4hFY8JHWvYVNjfWn4azeVzmajK83qDUnGc7 kuvGIHu2Bk8B1HdT8ton =SGFU -----END PGP SIGNATURE----- --cNdxnHkX5QqsyA0e--