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=-9.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 CB2EDC7618F for ; Wed, 17 Jul 2019 15:40:29 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AA76C2173B for ; Wed, 17 Jul 2019 15:40:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AA76C2173B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 0DE8BDD2; Wed, 17 Jul 2019 15:40:14 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id F20BADA4 for ; Wed, 17 Jul 2019 15:31:48 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mx1.suse.de (mx2.suse.de [195.135.220.15]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 87D51756 for ; Wed, 17 Jul 2019 15:31:48 +0000 (UTC) X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id EB414B048; Wed, 17 Jul 2019 15:31:46 +0000 (UTC) From: Nicolas Saenz Julienne To: linux-arm-kernel@lists.infradead.org, Christoph Hellwig , Marek Szyprowski , Robin Murphy Subject: [RFC 3/4] dma-direct: add dma_direct_min_mask Date: Wed, 17 Jul 2019 17:31:34 +0200 Message-Id: <20190717153135.15507-4-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190717153135.15507-1-nsaenzjulienne@suse.de> References: <20190717153135.15507-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 X-Mailman-Approved-At: Wed, 17 Jul 2019 15:40:12 +0000 Cc: stefan.wahren@i2se.com, f.fainelli@gmail.com, catalin.marinas@arm.com, phil@raspberrypi.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Jisheng.Zhang@synaptics.com, mbrugger@suse.com, will@kernel.org, Nicolas Saenz Julienne X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Historically devices with ZONE_DMA32 have been assumed to be able to address at least the lower 4GB of ram for DMA. This is still the defualt behavior yet the Raspberry Pi 4 is limited to the first GB of memory. This has been observed to trigger failures in dma_direct_supported() as the 'min_mask' isn't properly set. We create 'dma_direct_min_mask' in order for the arch init code to be able to fine-tune dma direct's 'min_dma' mask. Signed-off-by: Nicolas Saenz Julienne --- kernel/dma/direct.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index b90e1aede743..3c8cd730648b 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -23,6 +23,8 @@ #define ARCH_ZONE_DMA_BITS 24 #endif +u64 dma_direct_min_mask __ro_after_init = DMA_BIT_MASK(32); + /* * For AMD SEV all DMA must be to unencrypted addresses. */ @@ -393,7 +395,7 @@ int dma_direct_supported(struct device *dev, u64 mask) if (IS_ENABLED(CONFIG_ZONE_DMA)) min_mask = DMA_BIT_MASK(ARCH_ZONE_DMA_BITS); else - min_mask = DMA_BIT_MASK(32); + min_mask = dma_direct_min_mask; min_mask = min_t(u64, min_mask, (max_pfn - 1) << PAGE_SHIFT); -- 2.22.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu