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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=unavailable 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 7529DC04AA7 for ; Mon, 13 May 2019 11:42:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4EE342070D for ; Mon, 13 May 2019 11:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728297AbfEMLma (ORCPT ); Mon, 13 May 2019 07:42:30 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:56708 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727202AbfEMLma (ORCPT ); Mon, 13 May 2019 07:42:30 -0400 Received: from penelope.horms.nl (ip4dab7138.direct-adsl.nl [77.171.113.56]) by kirsty.vergenet.net (Postfix) with ESMTPA id B8BAC25AD63; Mon, 13 May 2019 21:42:27 +1000 (AEST) Received: by penelope.horms.nl (Postfix, from userid 7100) id 9FA36E2232E; Mon, 13 May 2019 13:42:25 +0200 (CEST) Date: Mon, 13 May 2019 13:42:25 +0200 From: Simon Horman To: Geert Uytterhoeven Cc: "George G. Davis" , Eugeniu Rosca , Greg Kroah-Hartman , Jiri Slaby , "open list:SERIAL DRIVERS" , open list , Chris Brandt , Wolfram Sang , Ulrich Hecht , Andy Lowe , Linux-Renesas , OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS , Magnus Damm , Rob Herring , Mark Rutland , "George G. Davis" Subject: Re: [PATCH] serial: sh-sci: disable DMA for uart_console Message-ID: <20190513114225.jhd5in7zavd5wvbw@verge.net.au> References: <20190506194233.GA32430@vmlxhi-102.adit-jv.com> <1557413011-1662-1-git-send-email-george_davis@mentor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organisation: Horms Solutions BV User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org On Mon, May 13, 2019 at 01:13:16PM +0200, Geert Uytterhoeven wrote: > Hi George, > > On Thu, May 9, 2019 at 4:44 PM George G. Davis wrote: > > As noted in commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for > > console UART"), UART console lines use low-level PIO only access functions > > which will conflict with use of the line when DMA is enabled, e.g. when > > the console line is also used for systemd messages. So disable DMA > > support for UART console lines. > > > > Fixes: https://patchwork.kernel.org/patch/10929511/ > > Reported-by: Michael Rodin > > Cc: Eugeniu Rosca > > Signed-off-by: George G. Davis > > I think this makes sense. In addition to OMAP 8250, the same approach > is used in the Mediatek 8250 and iMX serial drivers. > > Regardless, this is definitely better than removing the "dmas" properties > from DT, as DT describes hardware, not usage policies. +1 > Anyone else with a comment? Reviewed-by: Simon Horman