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=-8.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_MUTT autolearn=ham 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 23E8FC04A6B for ; Fri, 10 May 2019 17:10:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9398208C3 for ; Fri, 10 May 2019 17:10:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727835AbfEJRKm (ORCPT ); Fri, 10 May 2019 13:10:42 -0400 Received: from smtp1.de.adit-jv.com ([93.241.18.167]:54827 "EHLO smtp1.de.adit-jv.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727796AbfEJRKm (ORCPT ); Fri, 10 May 2019 13:10:42 -0400 Received: from localhost (smtp1.de.adit-jv.com [127.0.0.1]) by smtp1.de.adit-jv.com (Postfix) with ESMTP id 8DBF83C00C6; Fri, 10 May 2019 19:10:39 +0200 (CEST) Received: from smtp1.de.adit-jv.com ([127.0.0.1]) by localhost (smtp1.de.adit-jv.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 2dIuZMVPBgda; Fri, 10 May 2019 19:10:32 +0200 (CEST) Received: from HI2EXCH01.adit-jv.com (hi2exch01.adit-jv.com [10.72.92.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by smtp1.de.adit-jv.com (Postfix) with ESMTPS id C99FE3C004C; Fri, 10 May 2019 19:10:24 +0200 (CEST) Received: from vmlxhi-102.adit-jv.com (10.72.93.184) by HI2EXCH01.adit-jv.com (10.72.92.24) with Microsoft SMTP Server (TLS) id 14.3.439.0; Fri, 10 May 2019 19:10:24 +0200 Date: Fri, 10 May 2019 19:10:21 +0200 From: Eugeniu Rosca To: "George G. Davis" CC: Geert Uytterhoeven , Greg Kroah-Hartman , Jiri Slaby , "open list:SERIAL DRIVERS" , open list , Simon Horman , 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" , Eugeniu Rosca , Eugeniu Rosca Subject: Re: [PATCH] serial: sh-sci: disable DMA for uart_console Message-ID: <20190510171021.GA22691@vmlxhi-102.adit-jv.com> 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: <1557413011-1662-1-git-send-email-george_davis@mentor.com> User-Agent: Mutt/1.5.24 (2015-08-30) X-Originating-IP: [10.72.93.184] Sender: linux-renesas-soc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-renesas-soc@vger.kernel.org Hi George, I am able to reproduce the SCIF2 console freeze described in the referenced patchwork link using M3-ES1.1-Salvator-XS and recent v5.1-9573-gb970afcfcabd kernel. I confirm the behavior is healed with this patch. Thanks! Hope to see it accepted soon, since it fixes a super annoying console breakage every fourth boot or so on lots of R-Car3 targets. Tested-by: Eugeniu Rosca On Thu, May 09, 2019 at 10:43:30AM -0400, 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 > --- > drivers/tty/serial/sh-sci.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c > index 3cd139752d3f..885b56b1d4e4 100644 > --- a/drivers/tty/serial/sh-sci.c > +++ b/drivers/tty/serial/sh-sci.c > @@ -1557,6 +1557,9 @@ static void sci_request_dma(struct uart_port *port) > > dev_dbg(port->dev, "%s: port %d\n", __func__, port->line); > > + if (uart_console(port)) > + return; /* Cannot use DMA on console */ > + > if (!port->dev->of_node) > return; > > -- > 2.7.4 > -- Best Regards, Eugeniu.