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, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,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 136C8C00A89 for ; Fri, 30 Oct 2020 18:01:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BB43B2151B for ; Fri, 30 Oct 2020 18:01:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727134AbgJ3SBL (ORCPT ); Fri, 30 Oct 2020 14:01:11 -0400 Received: from mail.kernel.org ([198.145.29.99]:50854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726072AbgJ3SBF (ORCPT ); Fri, 30 Oct 2020 14:01:05 -0400 Received: from gaia (unknown [95.145.162.19]) (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 178E320A8B; Fri, 30 Oct 2020 18:01:01 +0000 (UTC) Date: Fri, 30 Oct 2020 18:00:55 +0000 From: Catalin Marinas To: Nicolas Saenz Julienne Cc: robh+dt@kernel.org, hch@lst.de, ardb@kernel.org, linux-kernel@vger.kernel.org, Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , robin.murphy@arm.com, linux-arm-kernel@lists.infradead.org, linux-rpi-kernel@lists.infradead.org, jeremy.linton@arm.com, iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, will@kernel.org, Anshuman Khandual , "Rafael J. Wysocki" , Len Brown , linux-acpi@vger.kernel.org Subject: Re: [PATCH v5 6/7] arm64: mm: Set ZONE_DMA size based on early IORT scan Message-ID: <20201030180055.GD23196@gaia> References: <20201029172550.3523-1-nsaenzjulienne@suse.de> <20201029172550.3523-7-nsaenzjulienne@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201029172550.3523-7-nsaenzjulienne@suse.de> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 29, 2020 at 06:25:49PM +0100, Nicolas Saenz Julienne wrote: > diff --git a/drivers/acpi/arm64/iort.c b/drivers/acpi/arm64/iort.c > index 9929ff50c0c0..05fe4a076bab 100644 > --- a/drivers/acpi/arm64/iort.c > +++ b/drivers/acpi/arm64/iort.c > @@ -1718,3 +1718,55 @@ void __init acpi_iort_init(void) > > iort_init_platform_devices(); > } > + > +#ifdef CONFIG_ZONE_DMA > +/* > + * Check the IORT whether any devices exist whose DMA mask is < 32 bits. > + * If so, return the smallest value encountered, or 32 otherwise. > + */ > +unsigned int __init acpi_iort_get_zone_dma_size(void) > +{ > + struct acpi_table_iort *iort; > + struct acpi_iort_node *node, *end; > + acpi_status status; > + u8 limit = 32; Nitpick: can we not return PHYS_ADDR_MAX here, for consistency with of_dma_get_max_cpu_address()? There wouldn't be any functional change. -- Catalin