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=-9.8 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 009D5C32751 for ; Wed, 31 Jul 2019 16:00:35 +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 CD9F8206A2 for ; Wed, 31 Jul 2019 16:00:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CD9F8206A2 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 D4E4C3EC2; Wed, 31 Jul 2019 15:59:49 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 3E48A3AA5 for ; Wed, 31 Jul 2019 15:48:13 +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 AF6B8E7 for ; Wed, 31 Jul 2019 15:48:12 +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 1CBAEB05E; Wed, 31 Jul 2019 15:48:11 +0000 (UTC) From: Nicolas Saenz Julienne To: catalin.marinas@arm.com, hch@lst.de, wahrenst@gmx.net, marc.zyngier@arm.com, Robin Murphy , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, iommu@lists.linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: [PATCH 8/8] mm: comment arm64's usage of 'enum zone_type' Date: Wed, 31 Jul 2019 17:47:51 +0200 Message-Id: <20190731154752.16557-9-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190731154752.16557-1-nsaenzjulienne@suse.de> References: <20190731154752.16557-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Cc: phill@raspberryi.org, f.fainelli@gmail.com, mbrugger@suse.com, frowand.list@gmail.com, eric@anholt.net, robh+dt@kernel.org, linux-rpi-kernel@lists.infradead.org, akpm@linux-foundation.org, will@kernel.org, nsaenzjulienne@suse.de 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 arm64 uses both ZONE_DMA and ZONE_DMA32 for the same reasons x86_64 does: peripherals with different DMA addressing limitations. This updates both ZONE_DMAs comments to inform about the usage. Signed-off-by: Nicolas Saenz Julienne --- include/linux/mmzone.h | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index d77d717c620c..8fa6bcf72e7c 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -365,23 +365,24 @@ enum zone_type { * * Some examples * - * Architecture Limit - * --------------------------- - * parisc, ia64, sparc <4G - * s390, powerpc <2G - * arm Various - * alpha Unlimited or 0-16MB. + * Architecture Limit + * ---------------------------------- + * parisc, ia64, sparc, arm64 <4G + * s390, powerpc <2G + * arm Various + * alpha Unlimited or 0-16MB. * * i386, x86_64 and multiple other arches - * <16M. + * <16M. */ ZONE_DMA, #endif #ifdef CONFIG_ZONE_DMA32 /* - * x86_64 needs two ZONE_DMAs because it supports devices that are - * only able to do DMA to the lower 16M but also 32 bit devices that - * can only do DMA areas below 4G. + * x86_64 and arm64 need two ZONE_DMAs because they support devices + * that are only able to DMA a fraction of the 32 bit addressable + * memory area, but also devices that are limited to that whole 32 bit + * area. */ ZONE_DMA32, #endif -- 2.22.0 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu