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=-12.7 required=3.0 tests=BAYES_00, 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 E2405C47429 for ; Thu, 1 Oct 2020 16:18:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B2E772145D for ; Thu, 1 Oct 2020 16:18:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732741AbgJAQSG (ORCPT ); Thu, 1 Oct 2020 12:18:06 -0400 Received: from mx2.suse.de ([195.135.220.15]:57888 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732026AbgJAQR6 (ORCPT ); Thu, 1 Oct 2020 12:17:58 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id DD042AF26; Thu, 1 Oct 2020 16:17:56 +0000 (UTC) From: Nicolas Saenz Julienne To: robh+dt@kernel.org, catalin.marinas@arm.com, hch@lst.de, robin.murphy@arm.com, devicetree@vger.kernel.org, iommu@lists.linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Cc: will@kernel.org, linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, Nicolas Saenz Julienne Subject: [PATCH 3/4] arm64: Default to 32-bit ZONE_DMA Date: Thu, 1 Oct 2020 18:17:39 +0200 Message-Id: <20201001161740.29064-4-nsaenzjulienne@suse.de> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201001161740.29064-1-nsaenzjulienne@suse.de> References: <20201001161740.29064-1-nsaenzjulienne@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The Raspberry Pi 4 needs two DMA zones as some of its devices can only DMA into the 30-bit physical address space. We solved that by creating an extra ZONE_DMA covering the 30-bit. It turns out that creating extra zones unnecessarily broke Kdump on large systems. So default to a single 32-bit wide ZONE_DMA and only define both zones if running on RPi4. Signed-off-by: Nicolas Saenz Julienne --- arch/arm64/mm/init.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index e1a69a618832..3c3f462466eb 100644 --- a/arch/arm64/mm/init.c +++ b/arch/arm64/mm/init.c @@ -43,8 +43,6 @@ #include #include -#define ARM64_ZONE_DMA_BITS 30 - /* * We need to be able to catch inadvertent references to memstart_addr * that occur (potentially in generic code) before arm64_memblock_init() @@ -388,8 +386,14 @@ void __init arm64_memblock_init(void) early_init_fdt_scan_reserved_mem(); if (IS_ENABLED(CONFIG_ZONE_DMA)) { - zone_dma_bits = ARM64_ZONE_DMA_BITS; - arm64_dma_phys_limit = max_zone_phys(ARM64_ZONE_DMA_BITS); + /* + * early_init_dt_scan() might alter zone_dma_bits based on the + * device's DT. Otherwise, have it cover the 32-bit address + * space. + */ + if (zone_dma_bits == ZONE_DMA_BITS_DEFAULT) + zone_dma_bits = 32; + arm64_dma_phys_limit = max_zone_phys(zone_dma_bits); } if (IS_ENABLED(CONFIG_ZONE_DMA32)) -- 2.28.0