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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 ADD84C10F13 for ; Thu, 11 Apr 2019 19:17:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 742E32173C for ; Thu, 11 Apr 2019 19:17:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726676AbfDKTRp (ORCPT ); Thu, 11 Apr 2019 15:17:45 -0400 Received: from foss.arm.com ([217.140.101.70]:48126 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726577AbfDKTRo (ORCPT ); Thu, 11 Apr 2019 15:17:44 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 15EEF374; Thu, 11 Apr 2019 12:17:44 -0700 (PDT) Received: from [192.168.1.123] (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 8A2D43F59C; Thu, 11 Apr 2019 12:17:42 -0700 (PDT) Subject: Re: [PATCH v2] arm64: dts: rockchip: add rk3399 UART DMAs From: Robin Murphy To: Heiko Stuebner Cc: Katsuhiro Suzuki , linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org References: <20190321162244.10080-1-katsuhiro@katsuster.net> <14265087.Gbs4YZABJo@phil> <69d5d0fd-00c3-36ae-596e-1b9f9452a07a@arm.com> <2463729.IUJ8mRE5Ts@phil> <8d164cfe-c345-aa45-aaf3-11983f9142e5@arm.com> Message-ID: <2e5a1468-9a65-9cc5-f96c-272faeb92ec9@arm.com> Date: Thu, 11 Apr 2019 20:17:36 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:60.0) Gecko/20100101 Thunderbird/60.6.1 MIME-Version: 1.0 In-Reply-To: <8d164cfe-c345-aa45-aaf3-11983f9142e5@arm.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019-04-11 2:48 pm, Robin Murphy wrote: > On 11/04/2019 13:46, Heiko Stuebner wrote: >> Hi Robin, >> >> Am Samstag, 30. März 2019, 00:24:16 CEST schrieb Robin Murphy: >>> On 2019-03-27 12:00 pm, Heiko Stuebner wrote: >>>> Hi, >>>> >>>> Am Dienstag, 26. März 2019, 14:49:16 CET schrieb Katsuhiro Suzuki: >>>>> Hello Robin, >>>>> >>>>> Sorry for inconvenience. Since I don't adhere enabling DMA for UARTs, >>>>> please revert my patch if you need. >>>> >>>> I've dropped the patch from my queue now. >>>> >>>>> BTW, there are DMA properties in RK3328 device-tree like as this >>>>> patch. >>>>> RK3328 UART DMA could not work correctly too...?? >>>> >>>> I remember Rockcihip dma-controllers having issues with burst-sizes >>>> and flushing (there is a no-flushp option in pl330), so it's >>>> possible that all share the same error up to rk3399 and rk3328 >>>> >>>> But so far no-one has shouted regarding the rk3328. >>> >>> Let me be the first, then, I guess :) >>> >>> I found an easy way to observe the problem on my 3399, and I've just >>> fired up my 3328 box with a 5.0 distro kernel to find that it behaves >>> the same. Basically just dump a large pile of text into 'less' on the >>> serial console, and scroll through line-by-line - certain lines get >>> dropped except for a few characters at the end. >>> >>> I'll see if I can narrow it down a bit, starting with trying >>> broken-flushp... >> >> did you manage to find time for that test you wanted to do? > > Sadly not - I got somewhat distracted by the ethernet thing, and since > then I've had too much else going on to follow up on any of my 'for fun' > projects :( Urgh, and it turns out what I thought were dropped characters seems to just be my console handling line wrapping weirdly, so now I have no idea if RK3328 actually has an issue, and coming up with a reliable reproducer for RK3399 is going to take some thought... Robin.