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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 1F36CC43381 for ; Wed, 3 Feb 2021 01:51:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E9A2264E27 for ; Wed, 3 Feb 2021 01:51:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231372AbhBCBvG (ORCPT ); Tue, 2 Feb 2021 20:51:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33372 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230369AbhBCBvA (ORCPT ); Tue, 2 Feb 2021 20:51:00 -0500 Received: from mail-wr1-x432.google.com (mail-wr1-x432.google.com [IPv6:2a00:1450:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 79E8FC06174A; Tue, 2 Feb 2021 17:50:20 -0800 (PST) Received: by mail-wr1-x432.google.com with SMTP id d16so22384211wro.11; Tue, 02 Feb 2021 17:50:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=/sDnQCoBJzd+G1dm09IQlU+bQBdo7KOQBQfZsd1ArQ0=; b=nMRLLe8JMleMFMolDyysYg3G2GQLLGzj1p+0EBXMboUMqWvFbD+atIXFkqjAjLYCRk 7q0uue/yRjX5F1PefvYifacevyoi+t3W9v/PsRcMdG7FP969aw/sZbN9C7jqRK2Kmjae +W83nZE99gLaJHAop3T+FycqEXEY5f3Jw1cKOgersHMzdqudPmhNe2yeWd77Xu7uwv51 E9e8V2leRVC8tyhmmEL1rVBVeYDPuWn61QMwA2ErXa6s0fV+YYprSv5VaPqROjLnMkfA WtdiRiRCEWnDBAR3C1rzDR1NSDRnLmuZcAdu4l7nl0YXSuTlkyOehjqnfYu7pt7dHI/9 OHBw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=/sDnQCoBJzd+G1dm09IQlU+bQBdo7KOQBQfZsd1ArQ0=; b=XFW7AjkZ8NaaEE6SPfoiBzoFRM0iG7sp+1PZQVUAXYEP5igeoiJC1Hwajc2MNT9eCb Rfp+KY04ukUOks1vBeCtm/RI1p9xngWFL+sSVXvmE0pRgscluuAST+gbolzVfq15IZwl l0ueGrMNsb/7opdhgSl9sJQmx3mNnkBizQefBFYzaJL2rQEYcm8rtWDk/QoOX30kggky RetLgaIg4ZwN+y8ml8H6jROEHk5fI2BLnD2D1BRcCiSwvVVYazegWg05JA4uRtXJqTG9 cg8lVzcBKzscAAwdXIKIthCZDgzTm71at1cHruZ7jwbbe7J/SNtwQm7nZvEin6iTK04j jdnA== X-Gm-Message-State: AOAM5331i8PKOj0pL9NwDWiJMG/Kq6rVuS5rNDlPMyH+7GPyXcg3HFzF uK+ZY/+gBlMoYIr4qbAo9D+VR/vXxM4mwU3C1AE= X-Google-Smtp-Source: ABdhPJyPpgBrxvykPqF+w1syFYv3dXpj7oxP5i2ZCmF+lg81VymYeH3nMLCZptiI1ZZ9uX/6Lz60WIqiFW5oI4LMSkg= X-Received: by 2002:adf:9427:: with SMTP id 36mr779616wrq.271.1612317019328; Tue, 02 Feb 2021 17:50:19 -0800 (PST) MIME-Version: 1.0 References: <20210202073258.559443-3-zhang.lyra@gmail.com> <20210202104257.736836-1-zhang.lyra@gmail.com> <20210202140101.GA32671@8bytes.org> <992fad43-c457-d809-3bd7-7fd5b6e8fa22@arm.com> <20210202144126.GC32671@8bytes.org> <5e766b74-ab51-8c47-66c1-ca65bc5743cd@arm.com> In-Reply-To: <5e766b74-ab51-8c47-66c1-ca65bc5743cd@arm.com> From: Chunyan Zhang Date: Wed, 3 Feb 2021 09:49:43 +0800 Message-ID: Subject: Re: [PATCH 2/2] iommu: add Unisoc iommu basic driver To: Robin Murphy Cc: Joerg Roedel , DTML , Linux Kernel Mailing List , Chunyan Zhang , Sheng Xu , Linux IOMMU , Rob Herring , Baolin Wang , Orson Zhai Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 3 Feb 2021 at 02:02, Robin Murphy wrote: > > On 2021-02-02 14:41, Joerg Roedel wrote: > > On Tue, Feb 02, 2021 at 02:34:34PM +0000, Robin Murphy wrote: > >> Nope, I believe if Arm Ltd. had any involvement in this I'd know about it :) > > > > Okay, got confused by thinking of ARM as the CPU architecture, not the > > company :) > > But given the intel/ and amd/ subdirectories refer to company names as > > well, the same is true for arm/. > > Right, trying to group IOMMU drivers by supposed CPU architecture is > already a demonstrable non-starter; does intel-iommu count as x86, or > IA-64, or do you want two copies? :P > > I somehow doubt anyone would license one of Arm's SMMUs to go in a > RISC-V/MIPS/etc. based SoC, but in principle, they *could*. In fact it's > precisely cases like this one - where silicon vendors come up with their > own little scatter-gather unit to go with their own display controller > etc. - that I imagine are most likely to get reused if the vendor > decides to experiment with different CPUs to reach new market segments. Yes, I agree, I believe this iommu unit along with Unisoc's multi-media modules can be used on other architecture SoCs, not only ARM based. > > Robin.