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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 DA167CA9EC4 for ; Wed, 30 Oct 2019 06:04:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AC0292087E for ; Wed, 30 Oct 2019 06:04:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=eero.com header.i=@eero.com header.b="JUb5oATa" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726895AbfJ3GEk (ORCPT ); Wed, 30 Oct 2019 02:04:40 -0400 Received: from mail-yw1-f65.google.com ([209.85.161.65]:41800 "EHLO mail-yw1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726234AbfJ3GEj (ORCPT ); Wed, 30 Oct 2019 02:04:39 -0400 Received: by mail-yw1-f65.google.com with SMTP id j131so469447ywa.8 for ; Tue, 29 Oct 2019 23:04:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=eero.com; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=VmzNbGg34FnbG5Nbkk0uiTVnFkTAGV+lRGweiedphdo=; b=JUb5oATapZ8cFR6+UNLQPySWl/+RFqK3ccphBvJAJx9Sn24eqYrpbzx9HMQeshfi2o zTp+vn87GasFaEJcMbP9sl1ZMS2GW2Md83UhldxxT/8i0uc+1DdCO5h/hWsj/txpPjQ+ 8OE/I4kdivJgObIFnU+/p9plKd+fkaCuELy2A= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=VmzNbGg34FnbG5Nbkk0uiTVnFkTAGV+lRGweiedphdo=; b=mEepPRQwAuV+GZns5cdV03t04MCXYks1KQLSvrp+cm3OOLd4QAch8GB48aVw7j+GL2 5GGrVYvNUxJULDqe8d1jS+yebWOxqTrcA1N/OOabW+N9cLOT5TPDmnhMrq9iyeZqGG4j Ltyi9ozdF20fjbRHLb72HXlv38BC5M6HljjLuJYMRX0xzs8fdYmKiDD6H/T7R7ylp3xs U8PV1JQDyWbbXPJzRCYM3MR32IqmsTafWsgIKbF/qzsU1Z3li63pwT4LR8qe/wxnY7Nq 359jlFUA41CZrADnmqH3/LlCuLg3mHjd6r20ECv+wF+9R7vxlJPijBIZOIGrBW+pCuOw lq5g== X-Gm-Message-State: APjAAAVxtMWS0N/KqTb6Xtrr5n8ZKvHGNpUZ4fj2Z6XiThQ4N94h7F97 hhICVoWukKqIZHHjCFrifX9ZnmnqqRE= X-Google-Smtp-Source: APXvYqyuiOOOuO6kU5b7wixMyo1Wa+E2D0aiRdAnTB816TlperTzJZvCLfKQkg4cEy47RNToZSh6Pg== X-Received: by 2002:a0d:c585:: with SMTP id h127mr20719404ywd.325.1572415478146; Tue, 29 Oct 2019 23:04:38 -0700 (PDT) Received: from [10.0.2.15] (75-25-130-58.lightspeed.sjcpca.sbcglobal.net. [75.25.130.58]) by smtp.gmail.com with ESMTPSA id d192sm846986ywb.3.2019.10.29.23.04.36 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 29 Oct 2019 23:04:37 -0700 (PDT) Subject: Re: [PATCH RFC] Revert "ath10k: fix DMA related firmware crashes on multiple devices" To: Adrian Chadd Cc: Zhi Chen , ath10k , linux-wireless@vger.kernel.org References: <1571734629-18028-1-git-send-email-zhichen@codeaurora.org> From: Peter Oh Message-ID: <8211c499-ec34-d1de-221e-e037e1fd0332@eero.com> Date: Tue, 29 Oct 2019 23:04:32 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On 10/22/19 11:24 AM, Adrian Chadd wrote: > On Tue, 22 Oct 2019 at 10:17, Peter Oh wrote: >> >> On 10/22/19 1:57 AM, Zhi Chen wrote: >>> This reverts commit 76d164f582150fd0259ec0fcbc485470bcd8033e. >>> PCIe hung issue was observed on multiple platforms. The issue was reproduced >>> when DUT was configured as AP and associated with 50+ STAs. >>> >>> With PCIe protocol analyzer, we can see DMA Read crossing 4KB boundary when >>> issue happened. It broke PCIe spec and caused PCIe stuck. Can you elaborate how 64 bytes DMA size breaks PCIe spec? >> How can you say value 0 (I believe it's 64 bytes) DMA burst size causes >> the symptom and 1 fixes it? > > +1 to this question. > > Also, shouldn't the DMA engine be doing what the firmware says? Is the > firmware/copy engine actually somehow bursting / prefetching across a > 4K page boundary? > > Surely this is something that can be fixed in software/firmware by > correctly configuring up buffer size/offsets? > > > > -adrian From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-yw1-xc43.google.com ([2607:f8b0:4864:20::c43]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iPh60-0008VT-1U for ath10k@lists.infradead.org; Wed, 30 Oct 2019 06:04:41 +0000 Received: by mail-yw1-xc43.google.com with SMTP id x65so459186ywf.12 for ; Tue, 29 Oct 2019 23:04:38 -0700 (PDT) Subject: Re: [PATCH RFC] Revert "ath10k: fix DMA related firmware crashes on multiple devices" References: <1571734629-18028-1-git-send-email-zhichen@codeaurora.org> From: Peter Oh Message-ID: <8211c499-ec34-d1de-221e-e037e1fd0332@eero.com> Date: Tue, 29 Oct 2019 23:04:32 -0700 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "ath10k" Errors-To: ath10k-bounces+kvalo=adurom.com@lists.infradead.org To: Adrian Chadd Cc: Zhi Chen , linux-wireless@vger.kernel.org, ath10k On 10/22/19 11:24 AM, Adrian Chadd wrote: > On Tue, 22 Oct 2019 at 10:17, Peter Oh wrote: >> >> On 10/22/19 1:57 AM, Zhi Chen wrote: >>> This reverts commit 76d164f582150fd0259ec0fcbc485470bcd8033e. >>> PCIe hung issue was observed on multiple platforms. The issue was reproduced >>> when DUT was configured as AP and associated with 50+ STAs. >>> >>> With PCIe protocol analyzer, we can see DMA Read crossing 4KB boundary when >>> issue happened. It broke PCIe spec and caused PCIe stuck. Can you elaborate how 64 bytes DMA size breaks PCIe spec? >> How can you say value 0 (I believe it's 64 bytes) DMA burst size causes >> the symptom and 1 fixes it? > > +1 to this question. > > Also, shouldn't the DMA engine be doing what the firmware says? Is the > firmware/copy engine actually somehow bursting / prefetching across a > 4K page boundary? > > Surely this is something that can be fixed in software/firmware by > correctly configuring up buffer size/offsets? > > > > -adrian _______________________________________________ ath10k mailing list ath10k@lists.infradead.org http://lists.infradead.org/mailman/listinfo/ath10k