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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CB7FBC433EF for ; Mon, 21 Feb 2022 12:59:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237459AbiBUNAB (ORCPT ); Mon, 21 Feb 2022 08:00:01 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:58780 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348732AbiBUNAA (ORCPT ); Mon, 21 Feb 2022 08:00:00 -0500 Received: from relay1-d.mail.gandi.net (relay1-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::221]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BAE471EADA for ; Mon, 21 Feb 2022 04:59:35 -0800 (PST) Received: (Authenticated sender: miquel.raynal@bootlin.com) by mail.gandi.net (Postfix) with ESMTPSA id 2BC3024000E; Mon, 21 Feb 2022 12:59:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1645448371; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=uhTsNJ0kQ/JteUN01wS0pWNvIJDnfr56O80qPFYTQnw=; b=Alwdtw0XSor57w4FVemMV1hXlcsJhPuvWYXPMpOc+ZmsLlD+gUr/85IBzkW4AEh+MpD9Pz GONNuZNjuZiWPr3bNNBzwK6A6XdPiC5plnS8DQk6Bpma9rwYKFVabKt7huyLV0/iL9eENv XZTvGh9ODK0HwLKXHOevSkDK4AAkYqgJdyDnwG/s2XIzRXjZ3MHMi5P2Xf2xZ7g4xnn6M0 inB2hbEUozQbq3ZVwUdXus0c9CPEr/xU0GRchwkQNWtDifsCCUeyLDWh/KfuGFRlROY2b+ QZGQ7WVCWy42MLbWe+rtfjbu9EK7fsFpxb0w7YF+53H2YJFefrpvR78+xxEuag== Date: Mon, 21 Feb 2022 13:59:27 +0100 From: Miquel Raynal To: Phil Edworthy Cc: Andy Shevchenko , Viresh Kumar , Vinod Koul , Geert Uytterhoeven , Magnus Damm , Michael Turquette , Stephen Boyd , Rob Herring , "devicetree@vger.kernel.org" , "dmaengine@vger.kernel.org" , "linux-renesas-soc@vger.kernel.org" , "linux-clk@vger.kernel.org" , Thomas Petazzoni , Milan Stevanovic , Jimmy Lalande , Laetitia MARIOTTINI Subject: Re: [PATCH 5/8] dma: dw: Avoid partial transfers Message-ID: <20220221135915.7a441663@xps13> In-Reply-To: References: <20220218181226.431098-1-miquel.raynal@bootlin.com> <20220218181226.431098-6-miquel.raynal@bootlin.com> Organization: Bootlin X-Mailer: Claws Mail 3.17.7 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Andy, phil.edworthy@renesas.com wrote on Mon, 21 Feb 2022 08:14:47 +0000: > Hi Andy, >=20 > I wrote the patch a few years ago, but didn't get the time to upstream it. >=20 > I am not aware of a HW integration bug on the RZ/N1 device but can't rule= it out. I am struggling to see what kind of HW issue this could be as, iir= c, word accesses work fine when the size of the transfer is a multiple of t= he MEM width. >=20 > I found the issue when testing DMA with the UART transferring different a= mounts of data. >=20 > > > + if (sconfig->dst_addr_width && sconfig->dst_addr_width < =20 > > data_width) =20 > > > + data_width =3D sconfig->dst_addr_width; =20 > >=20 > > But here no check that you do it for explicitly peripheral to memory, so > > this > > will affect memory to peripheral transfers as well. =20 > No, this should be ok as this change is within: > case DMA_DEV_TO_MEM: I will add this to the commit log to clarify. Thanks, Miqu=C3=A8l