Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751319AbcCIC3h (ORCPT ); Tue, 8 Mar 2016 21:29:37 -0500 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:45580 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750863AbcCIC33 (ORCPT ); Tue, 8 Mar 2016 21:29:29 -0500 Date: Wed, 9 Mar 2016 09:29:15 +0700 From: Mark Brown To: Ming Lei Cc: Stephen Boyd , Linux Kernel Mailing List , linux-arm@lists.infradead.org, Greg Kroah-Hartman , Robin Murphy , Laura Abbott , Arnd Bergmann , Marek Szyprowski , Andrew Morton , Catalin Marinas , Will Deacon , Vikram Mulukutla , Mimi Zohar Message-ID: <20160309022915.GB3898@sirena.org.uk> References: <1457428939-26659-1-git-send-email-stephen.boyd@linaro.org> <1457428939-26659-5-git-send-email-stephen.boyd@linaro.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="b5gNqxB1S1yM7hjW" Content-Disposition: inline In-Reply-To: X-Cookie: Do not flush. User-Agent: Mutt/1.5.24 (2015-08-30) X-SA-Exim-Connect-IP: 110.170.137.3 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [RFC/PATCH 4/4] firmware: Support requesting firmware directly into DMA memory 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 Content-Length: 1505 Lines: 37 --b5gNqxB1S1yM7hjW Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Mar 08, 2016 at 09:42:17PM +0800, Ming Lei wrote: > On Tue, Mar 8, 2016 at 5:22 PM, Stephen Boyd wrote: > > This design creates needless memory pressure and delays loading > > because we have to copy from kernel memory to somewhere else. > Given firmware request can't be a frequent operation, I don't think it is > a big deal about the so called memory pressure and delay. Boot time is a very important metric for some embedded product classes and is obviously one of the most common times when we need to load lots of firmware. Some mobile platforms have some individual firmwares that are getting on for 100M in size, holding a copy of one of them in RAM is a substantial proportion of the available memory in a system with 1-2G total especially when the system is also busy with other things. --b5gNqxB1S1yM7hjW Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJW34p6AAoJECTWi3JdVIfQvVoH/Ak1cA09iokCBgcVKX4Ng2sV VWXIxUTKb8wt2FLjHxXL7ApMpj8cvN/pKMXOtkxHUi1nQyjMc1/tx7EhArvzUlRr wge/2S78FewzTDhl+Qi5AP6gSKLtympsWKDTOOt0+u1r9kgIJil4rcyJsP4gifJr F8aN1pOxTmomtyLxrllvXoCmzfKuQ4bxRTI6wMUmyYYnhglu9LUMu8Vh+hOYFHX6 J/OXVVdzs0vQRT14GtVlgoxD2AiscYW635+uBvJHBxkpmLob1Fod2lWSDTySlLZd Ollj5WOFV2E0LxmRqDciGwuL5GoXgncxu1Z79Mm4Osm2F5oUf6qkHRqgIc0mR7U= =eK4C -----END PGP SIGNATURE----- --b5gNqxB1S1yM7hjW--