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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 E280CC7618F for ; Wed, 17 Jul 2019 14:23:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B872A21848 for ; Wed, 17 Jul 2019 14:23:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563373429; bh=GlgM6Flb7U5FvLBrim3MfffxSY9Cf03irtwOwK4KS08=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Jlrm5lAUjhiMIllWsd4ZQPrUUZDGKu4F7YoccBTMW6hAKAnXVjHOi7bWiAqE5soLh AnJJrTTJjbn1l5mLgVtnD0DNCY57r4WJSg8uFYV3NFsl0aneLmylhVoYWGUVSr5m8w iv+2YcU8xL7IcRfwcEtdvH9GxS2+WhnqkrQ3L6cI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727465AbfGQOXs (ORCPT ); Wed, 17 Jul 2019 10:23:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:50898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726452AbfGQOXs (ORCPT ); Wed, 17 Jul 2019 10:23:48 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (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 8568E21743; Wed, 17 Jul 2019 14:23:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1563373426; bh=GlgM6Flb7U5FvLBrim3MfffxSY9Cf03irtwOwK4KS08=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nEGGSoDItNpMBm7fRxdhPxrr5B8dn0+K1xshnV+ZF9QLHM9kqfyNzbDovXpkWgi6k L1J4PtnDOWbmj7aboaApmgn03y0Svo7KOZS+F8Ko1wo7KUVWvLev86ahSBecZnjw41 6fwNTWZl/I9y305D5xAlquohPhYf8EeD99abhAPI= Date: Wed, 17 Jul 2019 15:23:40 +0100 From: Will Deacon To: Yong Wu Cc: youlin.pei@mediatek.com, devicetree@vger.kernel.org, Nicolas Boichat , cui.zhang@mediatek.com, srv_heupstream@mediatek.com, chao.hao@mediatek.com, Joerg Roedel , Will Deacon , linux-kernel@vger.kernel.org, Evan Green , Tomasz Figa , iommu@lists.linux-foundation.org, Rob Herring , linux-mediatek@lists.infradead.org, Matthias Brugger , yingjoe.chen@mediatek.com, anan.sun@mediatek.com, Robin Murphy , Matthias Kaehlcke , linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v8 07/21] iommu/io-pgtable-arm-v7s: Extend MediaTek 4GB Mode Message-ID: <20190717142339.wltamw6wktwixqqn@willie-the-truck> References: <1561774167-24141-1-git-send-email-yong.wu@mediatek.com> <1561774167-24141-8-git-send-email-yong.wu@mediatek.com> <20190710143649.w5dplhzdpi3bxp7e@willie-the-truck> <1562846036.31342.10.camel@mhfsdcap03> <20190711123129.da4rg35b54u4svfw@willie-the-truck> <1563079280.31342.22.camel@mhfsdcap03> <20190715095156.xczfkbm6zpjueq32@willie-the-truck> <1563367459.31342.34.camel@mhfsdcap03> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1563367459.31342.34.camel@mhfsdcap03> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 17, 2019 at 08:44:19PM +0800, Yong Wu wrote: > On Mon, 2019-07-15 at 10:51 +0100, Will Deacon wrote: > > On Sun, Jul 14, 2019 at 12:41:20PM +0800, Yong Wu wrote: > > > @@ -742,7 +763,9 @@ static struct io_pgtable > > > *arm_v7s_alloc_pgtable(struct io_pgtable_cfg *cfg, > > > { > > > struct arm_v7s_io_pgtable *data; > > > > > > - if (cfg->ias > ARM_V7S_ADDR_BITS || cfg->oas > ARM_V7S_ADDR_BITS) > > > + if (cfg->ias > ARM_V7S_ADDR_BITS || > > > + (cfg->oas > ARM_V7S_ADDR_BITS && > > > + !(cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_EXT))) > > > return NULL; > > > > I think you can rework this to do something like: > > > > if (cfg->ias > ARM_V7S_ADDR_BITS) > > return NULL; > > > > if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_EXT) { > > if (!IS_ENABLED(CONFIG_PHYS_ADDR_T_64BIT)) > > cfg->oas = min(cfg->oas, ARM_V7S_ADDR_BITS); > > else if (cfg->oas > 34) > > return NULL; > > } else if (cfg->oas > ARM_V7S_ADDR_BITS) { > > return NULL; > > } > > > > so that we clamp the oas when phys_addr_t is 32-bit for you. That should > > allow you to remove lots of the checking from iopte_to_paddr() too if you > > check against oas in the map() function. > > > > Does that make sense? > > Of course I'm ok for this. I'm only afraid that this function has > already 3 checking "if (x) return NULL", Here we add a new one and so > many lines... Maybe the user should guarantee the right value of oas. > How about move it into mtk_iommu.c? > > About the checking of iopte_to_paddr, I can not remove them. I know it > may be a bit special and not readable. Hmm, I guess I should use a MACRO > instead of the hard code 33 for the special 4GB mode case. Why can't you just do something like: if (!(cfg->quirks & IO_PGTABLE_QUIRK_ARM_MTK_EXT)) return paddr; if (pte & ARM_V7S_ATTR_MTK_PA_BIT33) paddr |= BIT_ULL(33); if (pte & ARM_V&S_ATTR_MTK_PA_BIT32) paddr |= BIT_ULL(32); return paddr; The diff I sent previously sanitises the oas at init time, and then you can just enforce it in map(). Will