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=-8.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 1951AC4727E for ; Thu, 1 Oct 2020 17:20:43 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 C46AE20706 for ; Thu, 1 Oct 2020 17:20:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="xmVxD/ya" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C46AE20706 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=rV4W3AmmxV6lXIunXU/0228/w+lcj78F/N/NbyWKhxs=; b=xmVxD/yaO9C8fj9izT1mX6CEr bThIeIPqsNGNWzHIbNx4dVnv2JU7D5n1WhbnfIulEIUqa2SSK56BYo/aike8AgdvSTTz+JdKe43B3 2bqqqkc2FDA1+8Te8gbzWY7J/AGwb/PY5zYsaVkGGJZHxGLPePJIFdCg0M2uHIj2kXx5iXThzO8Yt A91Xqb8YgxGFczS4afGL3jSBy5jvtIlyKCC03x5MYQYMvNNqV33SXFGHyp+Xd2OWYFcTKI9usl0Wi 9lSQXI834421tJge61cX9JID0fIvfs5Tnt5QEoKR+MtWprxZrD1Q4pmroBLj8L58HDikiCtZGR0+F /KpcpMksw==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kO2Es-0006nn-OT; Thu, 01 Oct 2020 17:19:30 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kO2Ep-0006mO-K1; Thu, 01 Oct 2020 17:19:28 +0000 Received: from gaia (unknown [31.124.44.166]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 069D92085B; Thu, 1 Oct 2020 17:19:24 +0000 (UTC) Date: Thu, 1 Oct 2020 18:19:22 +0100 From: Catalin Marinas To: Nicolas Saenz Julienne Subject: Re: [PATCH 3/4] arm64: Default to 32-bit ZONE_DMA Message-ID: <20201001171922.GO21544@gaia> References: <20201001161740.29064-1-nsaenzjulienne@suse.de> <20201001161740.29064-4-nsaenzjulienne@suse.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20201001161740.29064-4-nsaenzjulienne@suse.de> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201001_131928_112822_F28901D8 X-CRM114-Status: GOOD ( 18.52 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, will@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, robh+dt@kernel.org, linux-rpi-kernel@lists.infradead.org, robin.murphy@arm.com, hch@lst.de, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Oct 01, 2020 at 06:17:39PM +0200, Nicolas Saenz Julienne wrote: > 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); So here we assume that if zone_dma_bits is 24, it wasn't initialised. I think it may be simpler if we just set it in setup_machine_fdt() to 32 or 30 if RPi4. This way we don't have to depend on what the core kernel sets. -- Catalin _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel