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=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 850D6C433E0 for ; Wed, 27 Jan 2021 19:34:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3EE8964DA1 for ; Wed, 27 Jan 2021 19:34:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344441AbhA0TdV (ORCPT ); Wed, 27 Jan 2021 14:33:21 -0500 Received: from foss.arm.com ([217.140.110.172]:33826 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344209AbhA0TcH (ORCPT ); Wed, 27 Jan 2021 14:32:07 -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 66C20106F; Wed, 27 Jan 2021 11:31:21 -0800 (PST) Received: from [10.57.47.135] (unknown [10.57.47.135]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 2B7D03F68F; Wed, 27 Jan 2021 11:31:19 -0800 (PST) Subject: Re: [PATCH v2] of/device: Update dma_range_map only when dev has valid dma-ranges To: Rob Herring , Yong Wu Cc: devicetree@vger.kernel.org, Nicolas Boichat , srv_heupstream , Will Deacon , Frank Rowand , "linux-kernel@vger.kernel.org" , Krzysztof Kozlowski , Paul Kocialkowski , Tomasz Figa , Linux IOMMU , "moderated list:ARM/Mediatek SoC support" , Matthias Brugger , linux-arm-kernel References: <20210119105203.15530-1-yong.wu@mediatek.com> From: Robin Murphy Message-ID: <9fb4c940-32e9-2da3-6e6a-eff5d1cd73ac@arm.com> Date: Wed, 27 Jan 2021 19:31:17 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Thunderbird/78.6.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-01-27 19:07, Rob Herring wrote: > On Tue, Jan 19, 2021 at 4:52 AM Yong Wu wrote: >> >> The commit e0d072782c73 ("dma-mapping: introduce DMA range map, >> supplanting dma_pfn_offset") always update dma_range_map even though it was >> already set, like in the sunxi_mbus driver. the issue is reported at [1]. >> This patch avoid this(Updating it only when dev has valid dma-ranges). > > only when dev *doesn't* have valid dma-ranges? I believe the intent is to mean when a valid "dma-ranges" property is specified in DT. The implementation allows DT to take precedence even if platform code *has* already installed a dma_range_map, although we shouldn't expect that to ever happen (except perhaps in the wild early days of platform bringup). Robin. >> Meanwhile, dma_range_map contains the devices' dma_ranges information, >> This patch moves dma_range_map before of_iommu_configure. The iommu >> driver may need to know the dma_address requirements of its iommu >> consumer devices. >> >> [1] https://lore.kernel.org/linux-arm-kernel/5c7946f3-b56e-da00-a750-be097c7ceb32@arm.com/ >> >> CC: Rob Herring >> CC: Frank Rowand >> Fixes: e0d072782c73 ("dma-mapping: introduce DMA range map, supplanting dma_pfn_offset"), >> Suggested-by: Robin Murphy >> Signed-off-by: Yong Wu >> Signed-off-by: Paul Kocialkowski >> Reviewed-by: Rob Herring >> --- >> drivers/of/device.c | 10 +++++++--- >> 1 file changed, 7 insertions(+), 3 deletions(-) >> >> diff --git a/drivers/of/device.c b/drivers/of/device.c >> index aedfaaafd3e7..1122daa8e273 100644 >> --- a/drivers/of/device.c >> +++ b/drivers/of/device.c >> @@ -162,9 +162,11 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, >> mask = DMA_BIT_MASK(ilog2(end) + 1); >> dev->coherent_dma_mask &= mask; >> *dev->dma_mask &= mask; >> - /* ...but only set bus limit if we found valid dma-ranges earlier */ >> - if (!ret) >> + /* ...but only set bus limit and range map if we found valid dma-ranges earlier */ >> + if (!ret) { >> dev->bus_dma_limit = end; >> + dev->dma_range_map = map; >> + } >> >> coherent = of_dma_is_coherent(np); >> dev_dbg(dev, "device is%sdma coherent\n", >> @@ -172,6 +174,9 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, >> >> iommu = of_iommu_configure(dev, np, id); >> if (PTR_ERR(iommu) == -EPROBE_DEFER) { >> + /* Don't touch range map if it wasn't set from a valid dma-ranges */ >> + if (!ret) >> + dev->dma_range_map = NULL; >> kfree(map); >> return -EPROBE_DEFER; >> } >> @@ -181,7 +186,6 @@ int of_dma_configure_id(struct device *dev, struct device_node *np, >> >> arch_setup_dma_ops(dev, dma_start, size, iommu, coherent); >> >> - dev->dma_range_map = map; >> return 0; >> } >> EXPORT_SYMBOL_GPL(of_dma_configure_id); >> -- >> 2.18.0 >> > _______________________________________________ > iommu mailing list > iommu@lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu >