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=-2.2 required=3.0 tests=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 DDD44C432C0 for ; Thu, 21 Nov 2019 13:33:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD3EB20709 for ; Thu, 21 Nov 2019 13:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727007AbfKUNd5 (ORCPT ); Thu, 21 Nov 2019 08:33:57 -0500 Received: from foss.arm.com ([217.140.110.172]:56336 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726536AbfKUNd4 (ORCPT ); Thu, 21 Nov 2019 08:33:56 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E35FBDA7; Thu, 21 Nov 2019 05:33:55 -0800 (PST) Received: from [10.1.196.37] (e121345-lin.cambridge.arm.com [10.1.196.37]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 187683F703; Thu, 21 Nov 2019 05:33:53 -0800 (PST) Subject: Re: Bug 205201 - Booting halts if Dawicontrol DC-2976 UW SCSI board installed, unless RAM size limited to 3500M To: Christian Zigotzky , Christoph Hellwig Cc: linux-arch@vger.kernel.org, darren@stevens-zone.net, mad skateman , Benjamin Herrenschmidt , linux-kernel@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Rob Herring , paulus@samba.org, rtd2@xtra.co.nz, "contact@a-eon.com" , linuxppc-dev , nsaenzjulienne@suse.de References: <20191121072943.GA24024@lst.de> <6eec5c42-019c-a988-fc2a-cb804194683d@xenosoft.de> From: Robin Murphy Message-ID: Date: Thu, 21 Nov 2019 13:33:52 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <6eec5c42-019c-a988-fc2a-cb804194683d@xenosoft.de> 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 21/11/2019 12:21 pm, Christian Zigotzky wrote: > On 21 November 2019 at 01:16 pm, Christian Zigotzky wrote: >> On 21 November 2019 at 08:29 am, Christoph Hellwig wrote: >>> On Sat, Nov 16, 2019 at 08:06:05AM +0100, Christian Zigotzky wrote: >>>> /* >>>>   *  DMA addressing mode. >>>>   * >>>>   *  0 : 32 bit addressing for all chips. >>>>   *  1 : 40 bit addressing when supported by chip. >>>>   *  2 : 64 bit addressing when supported by chip, >>>>   *      limited to 16 segments of 4 GB -> 64 GB max. >>>>   */ >>>> #define   SYM_CONF_DMA_ADDRESSING_MODE >>>> CONFIG_SCSI_SYM53C8XX_DMA_ADDRESSING_MODE >>>> >>>> Cyrus config: >>>> >>>> CONFIG_SCSI_SYM53C8XX_DMA_ADDRESSING_MODE=1 >>>> >>>> I will configure “0 : 32 bit addressing for all chips” for the RC8. >>>> Maybe this is the solution. >>> 0 means you are going to do bounce buffering a lot, which seems >>> generally like a bad idea. >>> >>> But why are we talking about the sym53c8xx driver now?  The last issue >>> you reported was about video4linux allocations. >>> >> Both drivers have the same problem. They don't work if we have more >> than 3.5GB RAM. I try to find a solution until you have a good >> solution. I have already a solution for V4L but I still need one for >> the sym53c8xx driver. > OK, you mean that "0" is a bad idea but maybe it works until you have a > solution. ;-) Is this on the same machine with the funny non-power-of-two bus_dma_mask as your other report? If so, does Nicolas' latest patch[1] help at all? Robin. [1] https://lore.kernel.org/linux-iommu/20191121092646.8449-1-nsaenzjulienne@suse.de/T/#u