From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E93BBC43603 for ; Wed, 11 Dec 2019 10:47:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B324A206A5 for ; Wed, 11 Dec 2019 10:47:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576061262; bh=UZpQZWLyj5KTIrpKeJw9QJlsYXlOVRzjz84QXbg34aA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=UhT+R/TBEokJH7NWVIjxPmhoEEE8zf7sW1GOLjQkKV+Go2yOwCOaqhcKQHH6geYia 3l7BpWJ4rYF2McuJJWn/akhSBERJHwPVjhs8Xh7r2k38WWJQVgiBUln6gb+XJAUdEv MNei77wVO+fDhl5rf4swTes7EeHWq7zH3D+WwQt4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728543AbfLKKrl (ORCPT ); Wed, 11 Dec 2019 05:47:41 -0500 Received: from foss.arm.com ([217.140.110.172]:53422 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726119AbfLKKrl (ORCPT ); Wed, 11 Dec 2019 05:47:41 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 8A4311FB; Wed, 11 Dec 2019 02:47:40 -0800 (PST) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 04D693F6CF; Wed, 11 Dec 2019 02:47:39 -0800 (PST) Date: Wed, 11 Dec 2019 10:47:38 +0000 From: Mark Brown To: Sasha Levin Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Daniel Vetter , Sam Ravnborg , Noralf =?iso-8859-1?Q?Tr=F8nnes?= , Andy Shevchenko , Daniel Mack , Haojian Zhuang , Robert Jarzmik , linux-arm-kernel@lists.infradead.org, linux-spi@vger.kernel.org Subject: Re: [PATCH AUTOSEL 5.4 128/350] spi: pxa2xx: Set controller->max_transfer_size in dma mode Message-ID: <20191211104738.GA3870@sirena.org.uk> References: <20191210210735.9077-1-sashal@kernel.org> <20191210210735.9077-89-sashal@kernel.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="qDbXVdCdHGoSgWSk" Content-Disposition: inline In-Reply-To: <20191210210735.9077-89-sashal@kernel.org> X-Cookie: NOBODY EXPECTS THE SPANISH INQUISITION! User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --qDbXVdCdHGoSgWSk Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Tue, Dec 10, 2019 at 04:03:53PM -0500, Sasha Levin wrote: > From: Daniel Vetter >=20 > [ Upstream commit b2662a164f9dc48da8822e56600686d639056282 ] >=20 > In DMA mode we have a maximum transfer size, past that the driver > falls back to PIO (see the check at the top of pxa2xx_spi_transfer_one). > Falling back to PIO for big transfers defeats the point of a dma engine, > hence set the max transfer size to inform spi clients that they need > to do something smarter. This won't fix anything by itself, this asks other code to change how it behaves which may or may not work in older kernels. --qDbXVdCdHGoSgWSk Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQEzBAABCgAdFiEEreZoqmdXGLWf4p/qJNaLcl1Uh9AFAl3wyUcACgkQJNaLcl1U h9B1owf/c2+Di9MxB58DRS++wONQSVLBDBAzhSYBzUcKxUidr6Yieo8WKOq5RnZa Xfw5SuLTDnTe7S4iXTo0Gn3ejpU1Eb63YvCGs9+6bM4z3lfcU3wIzXUhW7OsmIxY HVSTa7iqOjusoR7WpboRgWRyFUdvcK4Y6jBUxh5roUD5IIojLGuVmk2QQVLlLaSq Mpw15lKs5DGIjq5AHQA0vmNDtjAhVdr/mFw3XSqeviIvfQ3H0CTbz6B8RIgiwGZ8 V9HDm7EeEHvb4H1nbeK9ileA1+Sor/2iGHt1Lwrb1xzKZJ+twuU6dB0NAkWcPv5A JCBMe73eK3vBVARzxfKmxEApfO37rQ== =C+Pn -----END PGP SIGNATURE----- --qDbXVdCdHGoSgWSk--