Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932082AbbDQJSu (ORCPT ); Fri, 17 Apr 2015 05:18:50 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:63275 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753339AbbDQJSl (ORCPT ); Fri, 17 Apr 2015 05:18:41 -0400 Message-ID: <5530CFEF.9080807@mentor.com> Date: Fri, 17 Apr 2015 18:18:39 +0900 From: jiwang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: Sebastian Andrzej Siewior CC: , , , , , , Subject: Re: [PATCH v1 11/15] serial: imx: initialized DMA w/o HW flow enabled References: <1418116296-12082-1-git-send-email-jiada_wang@mentor.com> <1418116296-12082-12-git-send-email-jiada_wang@mentor.com> <20150409120057.GA12596@breakpoint.cc> <552B72DF.7060006@mentor.com> <20150413080637.GA1537@breakpoint.cc> In-Reply-To: <20150413080637.GA1537@breakpoint.cc> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1702 Lines: 42 Hello Sebastian On 04/13/2015 05:06 PM, Sebastian Andrzej Siewior wrote: > On Mon, Apr 13, 2015 at 04:40:15PM +0900, jiwang wrote: >> Hi Sebastian > Hi Jiada, > >>> My question is how was this tested. Before your patch none of my boards >>> were using DMA because RTS/CTS is not in use and this was a key >>> requirement. Now SDMA goes crazy. Is there a SDMA firmware required for >>> this to work? >> We tested the patch set with our modified kernel tree, >> and I find upstream kernel is not building SDMA firmware, >> I will submit another patch to add it. > Please make sure it is tagged stable. There is no hint that this is required > and as of it now, it breaks v4.0. Due to missing of SDMA firmware, uart sdma mode is broken, but it is uncovered by this commit on your environment. > One question, where do you have the firmware from? I picked the one from FSL's > v3.10 SDK and I ended up with FIFO-overflows so it was clearly the wrong one > (and the built-in SDMA firmware does not work as expected as you mentioned). I got sdma firmware from FSL kernel tree. > Is this firmware only required the imx6 series or also for older versions like > imx5? the firmware only supports imx6 series, AFAIK, I checked with Freescale imx6 support team, due to licensing issue, I am not entitled to upstream FSL SDMA firmware. so seems currently disable SDMA support for uart is our only option at the moment. Thanks, Jiada >> Thanks, >> Jiada > Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/