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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 F31F0C43603 for ; Wed, 4 Dec 2019 12:35:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C690720865 for ; Wed, 4 Dec 2019 12:35:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575462935; bh=M1Wf/f30+BvSWegCWZV9CQ1OJDcWNvDUUneWC9hFQOQ=; h=From:To:Cc:Subject:Date:List-ID:From; b=hDM0r2L4TjUsP8AH8JW0OSYZiuimRxFcfQnwFOuuToQow3O2QC0wdv+ytWq3NKHb/ X6C60rRK8jHDPvzhD0yVvjQjjBLRSlT2tQIgQFpWPmaURjIg4XBo/HEJrZPw4pciwF 3LLw7M8Ct4QCc+LyXQLxenBzpbeemg7iSwdYg/7M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727833AbfLDMff (ORCPT ); Wed, 4 Dec 2019 07:35:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:34312 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726586AbfLDMfe (ORCPT ); Wed, 4 Dec 2019 07:35:34 -0500 Received: from aquarius.haifa.ibm.com (nesher1.haifa.il.ibm.com [195.110.40.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D7B2A20862; Wed, 4 Dec 2019 12:35:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575462933; bh=M1Wf/f30+BvSWegCWZV9CQ1OJDcWNvDUUneWC9hFQOQ=; h=From:To:Cc:Subject:Date:From; b=A+OJZidzgtdJt6409seAEyH45Ss0kz2SBVJ8TWk3Q0UceO0y4S6OsXy2bjaslg5lP LK6ARqr0xZruFvxNrlV5jBQ6dU6ReePVQk9HAWRwyTXGhM4FszRdjBL0OgxolzqKS0 a9CRC+a0jEEIjKw+N+wMhE7DRPXw7GklS56VuPLw= From: Mike Rapoport To: linux-kernel@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Mike Rapoport , Christian Zigotzky , Benjamin Herrenschmidt , Christoph Hellwig , Darren Stevens , mad skateman , Michael Ellerman , Nicolas Saenz Julienne , Paul Mackerras , Robin Murphy , Rob Herring Subject: [PATCH] powerpc: ensure that swiotlb buffer is allocated from low memory Date: Wed, 4 Dec 2019 14:35:24 +0200 Message-Id: <20191204123524.22919-1-rppt@kernel.org> X-Mailer: git-send-email 2.24.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mike Rapoport Some powerpc platforms (e.g. 85xx) limit DMA-able memory way below 4G. If a system has more physical memory than this limit, the swiotlb buffer is not addressable because it is allocated from memblock using top-down mode. Force memblock to bottom-up mode before calling swiotlb_init() to ensure that the swiotlb buffer is DMA-able. Link: https://lkml.kernel.org/r/F1EBB706-73DF-430E-9020-C214EC8ED5DA@xenosoft.de Reported-by: Christian Zigotzky Signed-off-by: Mike Rapoport Cc: Benjamin Herrenschmidt Cc: Christoph Hellwig Cc: Darren Stevens Cc: mad skateman Cc: Michael Ellerman Cc: Nicolas Saenz Julienne Cc: Paul Mackerras Cc: Robin Murphy Cc: Rob Herring --- arch/powerpc/mm/mem.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index be941d382c8d..14c2c53e3f9e 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -260,6 +260,14 @@ void __init mem_init(void) BUILD_BUG_ON(MMU_PAGE_COUNT > 16); #ifdef CONFIG_SWIOTLB + /* + * Some platforms (e.g. 85xx) limit DMA-able memory way below + * 4G. We force memblock to bottom-up mode to ensure that the + * memory allocated in swiotlb_init() is DMA-able. + * As it's the last memblock allocation, no need to reset it + * back to to-down. + */ + memblock_set_bottom_up(true); swiotlb_init(0); #endif -- 2.24.0