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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6E831C6FD1C for ; Fri, 24 Mar 2023 12:36:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: References:Message-ID:In-Reply-To:Subject:cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=OhVzwoKTXXK07HmSZerrA40kSUsTLK+cMrkvp9k4KEM=; b=L9NegZFq+89o9WesvfcznmOMWJ 44Vv0SjRjTrM4mUJ/ryJ4iKi+blOwRgiVs3+xqZHBWkap/Fauz7hLMLNUlrFNpnGFepb8aK9jXVIg 0zASjDYfYP0Y7BWbfoWzKXx/R7skwFZR/uJ/O53u6ClQUEqmHRb7HjIEkeUXgw74gcU2IFktZuMQE jv81ywmCdf7BPTtsMM/dc7HzVRknvOJE14X2tpdLjp7Ok8XXDqXaHar0A7F6H24vmgABXFVdpKsQW 8F0xYNINhCxKd4NUTsWdzf4q4fb+ud4V1dFulkwtJHQyIrpJfWFFKlVMG/HjLdRzsSE5FSpvSs0qn u0H0XzXg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1pfgdn-004Mt9-2m; Fri, 24 Mar 2023 12:35:31 +0000 Received: from mga14.intel.com ([192.55.52.115]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1pfgdk-004Msf-1Z for linux-arm-kernel@lists.infradead.org; Fri, 24 Mar 2023 12:35:29 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679661328; x=1711197328; h=date:from:to:cc:subject:in-reply-to:message-id: references:mime-version; bh=4UEUlRUAxbgrJwTxN1Lz8b/gdCkUHib8jgkLGCAHT54=; b=eDsvDDA+6hTq821KVYi0VOJsRZ7s+FeINxqoOtJM6tefVdgB4qSwnVsA 3pZQK0jQ90ZuzCmqQUA1v5bQ2Hi/q+GjlJjfVC5T4XiJu+Nr/tcTUyk6Z u8WiN8E23coUH5xZdYRRVGcybh/7Dd3DLgNHzz7xbn6wKCN3cseaVeGzY LZuheVmGuLLgsxZOP20rVxaW5ycv+gqracGCnbinGQC0zXSWNh+tuzmmv NFQP8d+BrsZkC+RXNXwME1q57m+fS1naJ2YmwKXcEQkjE50HvfomYfdVH VhNOV+EsL3NhwZr1za8Wji1csWzaS9Tc2nt/VrI1yd+wNXgzU0d+ucyWL A==; X-IronPort-AV: E=McAfee;i="6600,9927,10658"; a="339793068" X-IronPort-AV: E=Sophos;i="5.98,287,1673942400"; d="scan'208";a="339793068" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2023 05:35:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10658"; a="747148216" X-IronPort-AV: E=Sophos;i="5.98,287,1673942400"; d="scan'208";a="747148216" Received: from dmendyk-mobl2.ger.corp.intel.com ([10.252.38.125]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Mar 2023 05:35:18 -0700 Date: Fri, 24 Mar 2023 14:35:15 +0200 (EET) From: =?ISO-8859-15?Q?Ilpo_J=E4rvinen?= To: Francesco Dolcini cc: Stefan Wahren , =?ISO-8859-2?Q?Tomasz_Mo=F1?= , Greg Kroah-Hartman , Jiri Slaby , =?ISO-8859-15?Q?Uwe_Kleine-K=F6nig?= , Sergey Organov , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , NXP Linux Team , linux-serial , Linux ARM , Shawn Guo , Stefan Wahren Subject: Re: Regression: serial: imx: overrun errors on debug UART In-Reply-To: Message-ID: <989d6a6f-fd4d-3e53-d417-ddf71ccf7af@linux.intel.com> References: <2c29454b-9369-4360-8eb4-c151f59460cb@i2se.com> MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="8323329-121619625-1679661321=:2165" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230324_053528_552509_F36DCE60 X-CRM114-Status: GOOD ( 20.58 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-121619625-1679661321=:2165 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8BIT On Fri, 24 Mar 2023, Francesco Dolcini wrote: > Hello > > On Fri, Mar 24, 2023 at 01:47:59PM +0200, Ilpo Järvinen wrote: > > On Fri, 24 Mar 2023, Stefan Wahren wrote: > > > after switching to Linux 6.1.21 on our Tarragon board (i.MX6ULL SoC), we > > > experience the following issues with the debug UART (115200 baud, 8N1, no > > > hardware flow control): > > > > > > - overrun errors if we paste in multiple text lines while system is idle > > > - no reaction to single key strokes while system is on higher load > > > > > > After reverting 7a637784d517 ("serial: imx: reduce RX interrupt frequency") > > > the issue disappear. > > > > > > Maybe it's worth to mention that the Tarragon board uses two additional > > > application UARTs with similiar baud rates (9600 - 115200 baud, no hardware > > > flow control) for RS485 communication, but there are no overrun errors (with > > > and without the mention change). > > > > This has come up earlier, see e.g.: > > > > https://lore.kernel.org/linux-serial/20221003110850.GA28338@francesco-nb.int.toradex.com/ > > yep, it looks exactly the same issue. > > We did not verify if this was affecting other UARTs. However, isn't RS485 > half-duplex? While half-duplex is more likely by far due simplicity, RS485 could also be full-duplex. It seems imx driver supports for both modes. -- i. > This is very likely a difference compared to the RS232 > console port. > > I am also not really convinced this is a proper regression, while 7a637784d517 > clearly is making the situation _worst_, we had some issues even before - > unfortunately I have no much more details available. --8323329-121619625-1679661321=:2165 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --8323329-121619625-1679661321=:2165--