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=-13.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 4D3A2C4363A for ; Mon, 26 Oct 2020 11:36:13 +0000 (UTC) Received: from hemlock.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 A627A22250 for ; Mon, 26 Oct 2020 11:36:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A627A22250 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by hemlock.osuosl.org (Postfix) with ESMTP id C6DEB86FF3; Mon, 26 Oct 2020 11:36:11 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from hemlock.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 8uFzsPG-NvzC; Mon, 26 Oct 2020 11:36:09 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by hemlock.osuosl.org (Postfix) with ESMTP id A1F9A81B5E; Mon, 26 Oct 2020 11:36:09 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 9642CC088B; Mon, 26 Oct 2020 11:36:09 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 7AE95C0051 for ; Mon, 26 Oct 2020 11:36:08 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 695A786712 for ; Mon, 26 Oct 2020 11:36:08 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id r1J93YrgEdUC for ; Mon, 26 Oct 2020 11:36:06 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by whitealder.osuosl.org (Postfix) with ESMTP id C8A808670E for ; Mon, 26 Oct 2020 11:36:06 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A68D3101E; Mon, 26 Oct 2020 04:36:05 -0700 (PDT) Received: from [10.57.50.191] (unknown [10.57.50.191]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id A3DC63F719; Mon, 26 Oct 2020 04:36:02 -0700 (PDT) Subject: Re: [PATCH v3 11/24] iommu/io-pgtable-arm-v7s: Quad lvl1 pgtable for MediaTek To: Yong Wu References: <20200930070647.10188-1-yong.wu@mediatek.com> <20200930070647.10188-12-yong.wu@mediatek.com> <1603698083.26323.87.camel@mhfsdcap03> From: Robin Murphy Message-ID: <7a03faf4-b382-2923-b9fa-9a55861f49d6@arm.com> Date: Mon, 26 Oct 2020 11:35:56 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Thunderbird/78.4.0 MIME-Version: 1.0 In-Reply-To: <1603698083.26323.87.camel@mhfsdcap03> Content-Language: en-GB Cc: youlin.pei@mediatek.com, devicetree@vger.kernel.org, Nicolas Boichat , srv_heupstream@mediatek.com, chao.hao@mediatek.com, kernel-team@android.com, Greg Kroah-Hartman , linux-kernel@vger.kernel.org, Evan Green , Tomasz Figa , iommu@lists.linux-foundation.org, Rob Herring , linux-mediatek@lists.infradead.org, Krzysztof Kozlowski , Matthias Brugger , ming-fan.chen@mediatek.com, anan.sun@mediatek.com, Will Deacon , linux-arm-kernel@lists.infradead.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On 2020-10-26 07:41, Yong Wu wrote: > On Fri, 2020-10-23 at 15:10 +0100, Robin Murphy wrote: >> On 2020-09-30 08:06, Yong Wu wrote: >>> The standard input iova bits is 32. MediaTek quad the lvl1 pagetable >>> (4 * lvl1). No change for lvl2 pagetable. Then the iova bits can reach >>> 34bit. >>> >>> Signed-off-by: Yong Wu >>> --- >>> drivers/iommu/io-pgtable-arm-v7s.c | 13 ++++++++++--- >>> drivers/iommu/mtk_iommu.c | 2 +- >>> 2 files changed, 11 insertions(+), 4 deletions(-) >>> >>> diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c >>> index 8362fdf76657..306bae2755ed 100644 >>> --- a/drivers/iommu/io-pgtable-arm-v7s.c >>> +++ b/drivers/iommu/io-pgtable-arm-v7s.c >>> @@ -50,10 +50,17 @@ >>> */ >>> #define ARM_V7S_ADDR_BITS 32 >>> #define _ARM_V7S_LVL_BITS(lvl) (16 - (lvl) * 4) >>> +/* MediaTek: totally 34bits, 14bits at lvl1 and 8bits at lvl2. */ >>> +#define _ARM_V7S_LVL_BITS_MTK(lvl) (20 - (lvl) * 6) >> >> This should defined in terms of both lvl and cfg->ias. The formula here >> is nothing more than a disgusting trick I made up since a linear >> interpolation happened to fit the required numbers. That said, all of >> these bits pretending that short-descriptor is a well-defined recursive >> format only served to allow the rest of the code to look more like the >> LPAE code - IIRC they've already diverged a fair bit since then, so >> frankly a lot of this could stand to be unpicked and made considerably >> clearer by simply accepting that level 1 and level 2 are different from >> each other. > > If the formula is not good and make it clearer, How about this? > > > /* > * We have 32 bits total; 12 bits resolved at level 1, 8 bits at level > 2, > -* and 12 bits in a page. With some carefully-chosen coefficients we can > -* hide the ugly inconsistencies behind these macros and at least let > the > -* rest of the code pretend to be somewhat sane. > +* and 12 bits in a page. > +* > +* MediaTek extend 2 bits to reach 34 bits, 14 bits at lvl1 and 8 bits > at lvl2. > */ > > -#define _ARM_V7S_LVL_BITS(lvl) (16 - (lvl) * 4) > +#define _ARM_V7S_LVL1_BITS_NR(cfg) (((cfg)->ias == 32) ? 12 : 14) > +#define _ARM_V7S_LVL2_BITS_NR 8 > + > +#define _ARM_V7S_LVL_BITS(lvl, cfg) \ > + (((lvl) == 1) ? _ARM_V7S_LVL1_BITS_NR(cfg):_ARM_V7S_LVL2_BITS_NR) Well, I'd have gone for something really simple and clear like: #define ARM_V7S_LVL_BITS(lvl, cfg) ((lvl) == 1 ? (cfg)->ias - 20 : 8) #define ARM_V7S_LVL_SHIFT(lvl) ((lvl) == 1 ? 20 : 12) Then maybe see if enough of the users could resolve lvl significantly earlier to make it worth splitting things up further. Robin. >>> #define ARM_V7S_LVL_SHIFT(lvl) (ARM_V7S_ADDR_BITS - (4 + 8 * (lvl))) >>> #define ARM_V7S_TABLE_SHIFT 10 >>> >>> -#define ARM_V7S_PTES_PER_LVL(lvl, cfg) (1 << _ARM_V7S_LVL_BITS(lvl)) >>> +#define ARM_V7S_PTES_PER_LVL(lvl, cfg) ({ \ >>> + int _lvl = lvl; \ >>> + !arm_v7s_is_mtk_enabled(cfg) ? \ >>> + (1 << _ARM_V7S_LVL_BITS(_lvl)) : (1 << _ARM_V7S_LVL_BITS_MTK(_lvl));\ >>> +}) >>> + >>> #define ARM_V7S_TABLE_SIZE(lvl, cfg) \ >>> (ARM_V7S_PTES_PER_LVL(lvl, cfg) * sizeof(arm_v7s_iopte)) >>> >>> @@ -63,7 +70,7 @@ >>> #define _ARM_V7S_IDX_MASK(lvl, cfg) (ARM_V7S_PTES_PER_LVL(lvl, cfg) - 1) >>> #define ARM_V7S_LVL_IDX(addr, lvl, cfg) ({ \ >>> int _l = lvl; \ >>> - ((u32)(addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l, cfg); \ >>> + ((addr) >> ARM_V7S_LVL_SHIFT(_l)) & _ARM_V7S_IDX_MASK(_l, cfg); \ >>> }) >>> >>> /* >>> @@ -755,7 +762,7 @@ 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) >>> + if (cfg->ias > (arm_v7s_is_mtk_enabled(cfg) ? 34 : ARM_V7S_ADDR_BITS)) >>> return NULL; >>> >>> if (cfg->oas > (arm_v7s_is_mtk_enabled(cfg) ? 35 : ARM_V7S_ADDR_BITS)) >>> diff --git a/drivers/iommu/mtk_iommu.c b/drivers/iommu/mtk_iommu.c >>> index f6a2e3eb59d2..6e85c9976a33 100644 >>> --- a/drivers/iommu/mtk_iommu.c >>> +++ b/drivers/iommu/mtk_iommu.c >>> @@ -316,7 +316,7 @@ static int mtk_iommu_domain_finalise(struct mtk_iommu_domain *dom) >>> IO_PGTABLE_QUIRK_TLBI_ON_MAP | >>> IO_PGTABLE_QUIRK_ARM_MTK_EXT, >>> .pgsize_bitmap = mtk_iommu_ops.pgsize_bitmap, >>> - .ias = 32, >>> + .ias = 34, >>> .oas = 35, >>> .tlb = &mtk_iommu_flush_ops, >>> .iommu_dev = data->dev, >>> > _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu