From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9D5763AB47E; Mon, 17 Aug 2026 09:55:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786960508; cv=none; b=BNp3Fj/OODY1Lvwl/n0I6StzM1d4sZ+Op+6BXcWwczyqvb+mscmEs4k6VOm1VcMEP3z9qO5W4q6+BV4JlfZRwBa5TSP+p1eLcuaNtD0lnYKHTiZM9ndgGsVQxr0w8QWJ2PTHHEB6x29Yl2HBBnbDQz2ojUh+5FEvO8ILfoUksjg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1786960508; c=relaxed/simple; bh=wplaBJDMkV25nU9sxF6S09uQ1TlArf0Uk2IpJewXnT4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OdRuBHPVeNw46u8j16cgb4QZ4srvR+7bqrY3yd0tCwkQHMprOYQxNpegxXWTWdeQXr937bQ1d1ByWBnpwZ+RY5xV/DI7YEt7+QroR2/DS1jx+0i3FP2MLb1LJ3NLKk99qZw7pGLTHz9DTIcEPNEC3WWRqc35LGG9UrJsf5/jeHg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LHp7JlD9; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LHp7JlD9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 36D101F000E9; Mon, 17 Aug 2026 09:54:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1786960507; bh=+Lv1NIWLjXK/CzfWPsyXDeMuZHAoY0c6NItRAMaTRxY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=LHp7JlD95ovgSe8r0bR72lGNqqz8lIIrBBVRUyh1pozBAv5uE+g9C6zFCQqjsMnkW DmUgJUMiQOSOoFt7Cc4v+LCWenjyqMc3Wf1Xs6ckxwFk3zEsAbYM9JZN793yXK6VYN KbSEhe8SNgjDJ2NY6Is305LoEzuuNmHEwzGh2OadlUX4D5hxMGwksUI8I5EB/FmRhg uA6TO5F4mU+T4tBbKsAwUaaFaf7tUvhJ3QBYhB02AF97L0UBINVaXb3cdAfzX5385r jcFZEAw6T2O717gnR5C9BNna5eJjT8FM4PHZPPuIunZtuKuM8EDvL44O42OzPGUu/I YozSSqCPt9PJw== Message-ID: Date: Mon, 17 Aug 2026 10:54:47 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 04/22] arm64: dts: qcom: hamoa: Reserve low IOVA range for Iris To: Rob Herring Cc: Vishnu Reddy , Dmitry Baryshkov , Vikash Garodia , Dikshita Agarwal , Mauro Carvalho Chehab , Krzysztof Kozlowski , Conor Dooley , Stanimir Varbanov , Sakari Ailus , Abhinav Kumar , Stephan Gerhold , Bjorn Andersson , Stanimir Varbanov , Konrad Dybcio , Johan Hovold , Neil Armstrong , Loic Poulain , Jorge Ramirez-Ortiz , Mansur Alisha Shaik , Andy Gross , Rob Clark , Stephen Boyd , Yassine Oudjana , Pierre-Hugues Husson , Marc Gonzalez , cros-qcom-dts-watchers@chromium.org, Matthias Kaehlcke , Douglas Anderson , AngeloGioacchino Del Regno , Aniket Masule , Malathi Gottam , Rajendra Nayak , Jonathan Marek , Dikshita Agarwal , Renjiang Han , Krzysztof Kozlowski , linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Bryan O'Donoghue , Mauro Carvalho Chehab , Konrad Dybcio , Krzysztof Kozlowski , Daniel J Blueman , stable@vger.kernel.org References: <20260807-iris_iova_600mb_fix-v1-0-3996f67e33f9@oss.qualcomm.com> <20260807-iris_iova_600mb_fix-v1-4-3996f67e33f9@oss.qualcomm.com> <20260807162405.GA896590-robh@kernel.org> <6ee7f32e-eb6c-e264-6f0d-541555f8fd62@oss.qualcomm.com> <56b3dfcf-b1ad-4192-8199-06c80cc5d124@kernel.org> From: Bryan O'Donoghue Content-Language: en-GB Autocrypt: addr=bod@kernel.org; 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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 10/08/2026 14:47, Rob Herring wrote: >>> As per the reserved-memory.yaml schema document, the iommu-addresses >>> property for IOVA reservation into /reserved-memory is allowed — it's >>> documented for IOVA carveout reservations: >>> https://github.com/devicetree-org/dt-schema/blob/main/dtschema/ >>> schemas/reserved-memory/reserved-memory.yaml#L56 >> I think that is an entirely reasonable reading of the text >> >> Quote: >> >> "If no "reg" property is specified, the "iommu-addresses" property >> defines carveout regions in the IOVA space for the given device. This >> can be useful if a certain memory region should not be mapped through >> the IOMMU." >> >> Which is exactly what this series does. Excludes a specific IOVA range >> from being allocated for this device. > But if "iommu-addresses" is the only property of the reserved memory, > why put this property in reserved-memory rather than directly in the > device's node? I'm only questioning where is the right place to > describe a reserved IOVA. > > Rob Back from the eclipse, sorry for the delayed response. Ah I get you. Yes. I take your point. This is a property of the node itself; the IOVA < 600MB only matters _if_ the venus or iris nodes are enabled - otherwise an IOVA < 600MB is perfectly fine. So it follows its a property specific to this node not specific to the overall system. Yep, I agree - its a device/node property, not a top-level property. --- bod