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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2A203C4451C for ; Sat, 18 Jul 2026 14:32:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=qT89Wi3RAN9CgJ0A7GdoQ7adS5M+Uxt5TfxmdTXEZ+Q=; b=4pOAb/EiLKnXp2CiIUPMgPr39+ OhK3Vm4rWNz9BfYN9+i7otIPDTthmBneXvUSYHbQf1s2A0lm2bZEvOSyHjv/UCKFShGmnsHbucbbf gbSggi8xBorEWI8zHAMTzG7DvCCShDaT8XcfY4Y3/1InNNd826+GOfn+eU5NT3r8yRb+K7BNSk1QM resgfUSWwK7peRhD4YcV3YPhvOAEJhWsy8KW+G3Ta80hU0JhlmKq2YyAb1Fm5QTNMv6xF1ByxbCy7 vRL4MwBm8hq9h3JRwOeB20BgiFTSL+hWQ81Jp6+RS0GlVQ4vPw44WiJUixq92Ik+m6sCRLzIEK6T4 Sp45jiNQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wl65m-00000004AYj-0hPt; Sat, 18 Jul 2026 14:32:38 +0000 Received: from mail-qk1-x732.google.com ([2607:f8b0:4864:20::732]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wl65k-00000004AY7-0GSA for linux-arm-kernel@lists.infradead.org; Sat, 18 Jul 2026 14:32:37 +0000 Received: by mail-qk1-x732.google.com with SMTP id af79cd13be357-930c0f9c1b1so76894785a.1 for ; Sat, 18 Jul 2026 07:32:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1784385154; x=1784989954; darn=lists.infradead.org; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:from:to:cc:subject :date:message-id:reply-to:content-type; bh=qT89Wi3RAN9CgJ0A7GdoQ7adS5M+Uxt5TfxmdTXEZ+Q=; b=Jfp1uZh0/YEuaDXliq1IH0NMSROm5OIBMlrQxNQzpeFmZxB8zLNQWUiDhK+RbAg3XN 9yGlRSrdbdlcZEJ5/Iwqsxt7FwfdLsn7Psa5gaW/mBZa9PBbMz/Yuvrc00oiUY1d4pjv OK24BRCHBtefq/R/nevOo1csSmCc3kTQIGiw1uoRoqqQe/+bqMRAibilGesKlVp66qZ8 Tdrp3oStONVa52ic+H3OAa/r7Dag/JJEjFOg4y20CKU+fkrA0ldc+U7yiuO6Z0p92ZuU RoHzmiZoHBOGTSrilquQ9BTkKqj82MXlwb2Ei/gCEPD8E0/43BtGJTzsMSImBqmGeRoJ 9unw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1784385154; x=1784989954; h=in-reply-to:content-disposition:content-type:mime-version :references:message-id:subject:cc:to:from:date:x-gm-gg :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to :content-type; bh=qT89Wi3RAN9CgJ0A7GdoQ7adS5M+Uxt5TfxmdTXEZ+Q=; b=mdCuUBzKd54hXu0skC4mzsWLUqYTlt1lBbV4gbBEcbjnyIQd4PZhNJ8cfDP2XR5XUD AiqqssuOTZoQhEwQFnu/uTEGJQJ12D+B3pX0rSbYMG6BWpUW5bsO7g2mF0Ue0E/dTID9 ML3pw64aQ3HC16YOhOEPBrbXgNlIfNkzeRY0+KEYbkwQ1raLcWouTBiDRZbS9Cx5zsN0 7Spq0oY9QeJNQwk/1TjG2HcqqkQp1oTgjPGW3PV0SSQpVRfnd82PzbrGr9c8uxI4WoQB 4K+KWarr4J+coWqXFuYdKpPCwJjM+Ff3APwx1UsWCRerk5FD0mwBh8waNZKJdTW96AHs uCZg== X-Forwarded-Encrypted: i=1; AHgh+RpOo9lxCu0de8u0+p5Mbjz3achys9UuId6pKLLAy4IayZ+hq3IU3hU2YJDSCLkv0gl4Hzp2oVjc4q+2GVY5179v@lists.infradead.org X-Gm-Message-State: AOJu0YzTw8fEYaH1seL5c7s/tJuvApJ+a7ha8CDTqVhLKbc0KvJzEDEs gls3ECA80pHrCbDvLGr/SGRL0evpqLhsQfeAC27QKR6lFXCYOvFeiYFMElmtOG8//G0= X-Gm-Gg: AfdE7clj0d3iSO2qtVrTdUU4xcis4IwefBayiX2DEgnUPzkIL57wpKQFD9Y9tfno4fF b+dRt+TobBI0841yMSz9oUwBM0lGsqJm+MUail7USjl/PQAtAYDQYa8i49cQIMid221soc/7SC6 YahIdFg1w9LV+c1qErwfRxQBQDmZFUwkwYNTZydrdiH4Vna17K9k1GbxZXjOxBlMifVqytBLji/ 0HorGwyDMckR2Ki6KH5iKqomn14WJCNJ+8bAWWamqvyADQxVsIDvcyVddUsnoHYFHFCDjKZdikX Idc8jNetCksz15jgvWqhq4yQUEkElMcWuBw50aBbimASiwh9ImfrIo7Xl31mR66CigcFX/og9mK WCBCv4CRzBhvXuYAAFS0PzgO/R3hUEI5IBfym8HN6P+zXfgcPfWEGL3csWabI X-Received: by 2002:a05:620a:4706:b0:915:6a2b:6265 with SMTP id af79cd13be357-930b41e282amr722435385a.44.1784385154410; Sat, 18 Jul 2026 07:32:34 -0700 (PDT) Received: from ziepe.ca ([159.2.72.92]) by smtp.gmail.com with ESMTPSA id af79cd13be357-930b542d1e5sm425204385a.23.2026.07.18.07.32.33 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 18 Jul 2026 07:32:33 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1wl65h-00000006T6V-0EUE; Sat, 18 Jul 2026 11:32:33 -0300 Date: Sat, 18 Jul 2026 11:32:33 -0300 From: Jason Gunthorpe To: Daniel Drake Cc: "Joerg Roedel (AMD)" , Will Deacon , Robin Murphy , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Florian Fainelli , Broadcom internal kernel review list , iommu@lists.linux.dev, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, nick.hollinghurst@raspberrypi.com Subject: Re: [PATCH 5/6] iommu: Add Broadcom BCM2712 IOMMU driver Message-ID: <20260718143233.GE701389@ziepe.ca> References: <20260712-bcm2712-iommu-submit-v1-0-80e10cdde2ea@reactivated.net> <20260712-bcm2712-iommu-submit-v1-5-80e10cdde2ea@reactivated.net> <20260712221125.GD1835788@ziepe.ca> <57f5675c-8bcd-4022-978b-9f7933bb0032@reactivated.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <57f5675c-8bcd-4022-978b-9f7933bb0032@reactivated.net> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260718_073236_246289_F96C06E6 X-CRM114-Status: GOOD ( 14.97 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sat, Jul 18, 2026 at 09:39:48AM +0100, Daniel Drake wrote: > I don't think I can use that because this setup uses an IOVA aperture at > base 0xA00000000, whereas generic_pt assumes it is managing a 0-indexed > virtual address space. So the driver has to intercept every incoming IOVA > and translate for the aperture, see how map_pages calls: When you say aperture here you mean we place an IOPTE at VA 0 but the dma_addr_t for that has to be adjusted to 0xA00000000 ? I wonder if DT can do this with dma-ranges or something, we have many other conditions where the dma_addr_t and the internal physical have offsets.. > I was wondering about making iommupt understand apertures and > translate accordingly, but I imagine you would want to keep that > kind of thing out of the generic fast path? We already have pt_full_va_prefix() which isn't strictly an offset but it it probably matches what this HW does. You can implement it in the broadcom format and return the prefix value. So long as the vasz fits within those trailing 0s. That's basically free and has no runtime cost on other formats. Jason