From nobody Fri Oct 10 13:59:18 2025 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 B4FD82DE1E7; Tue, 17 Jun 2025 12:25:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750163153; cv=none; b=mgrgkGyrlZ8hnTHujJK9bLW+iKodJ9nDOO6Vd2Vb0vmh/rZZRJTGtdkHS5BlUSh7j5M7gr9NJCrj4q2pYUSb9QY50l2Il72QPL1iUjjcwx90iM/iMtdbo3VAtA3vJ/D+haZKbBuwsmyBUY6fphiV/Hmbk10wnguHQX6JS6Pr55Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750163153; c=relaxed/simple; bh=cGUtX2I1TX5Mw8HpaioqDUtXETjbLf4kkml849rWcMw=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=bE4ozO7wIEIMrvCx/s1eIYJlpbZOuWokx7wd7RWs1uUV4fNdJ+tm06yyR+vIRVQFLZraeyAZiNZRULAN0BPgTI1BkLJVpAqhjpUMTHpY9pUxmJ2GLu4BvZKP3l3g2NnYzPFXvjajWzSyZBlaC1GDZ8Q1xkGNhmqCdrb2xDERjNI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=oyNvtZJT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="oyNvtZJT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FAB0C4CEE3; Tue, 17 Jun 2025 12:25:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1750163153; bh=cGUtX2I1TX5Mw8HpaioqDUtXETjbLf4kkml849rWcMw=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=oyNvtZJTwe9Sz99WD7ShA0zGmfxgCcGdao99HLk5tN2X7y9ZIuE3MRpyrrb9jceRh yiwI99sW5tqLk5h1Ru3IkHwCOvD4IweIb63HB51RBw/52H7UUhuX1Op9WWcF4qpsfu e3nUtmNP6rjwfrVWX+slB0Gyypk/I6gHPj38+7yWsJBQahxG86TA6w9hBWQzqqoDP5 kBN6wYvaJFbFIuDCppupW4CvLMZ5B+bY1Jud3hv/pq6FAWDVryyUhluw03rq+pyDPy RGFPYsoiuk+I2NRo27StaMb80N5sahwaO09wkxNON9Uf8/bx1FP1t2VJ/dBSZjt6Fn UR7yReJXNk+pg== From: Maxime Ripard Date: Tue, 17 Jun 2025 14:25:40 +0200 Subject: [PATCH v5 1/2] dt-bindings: reserved-memory: Introduce carved-out memory region binding Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250617-dma-buf-ecc-heap-v5-1-0abdc5863a4f@kernel.org> References: <20250617-dma-buf-ecc-heap-v5-0-0abdc5863a4f@kernel.org> In-Reply-To: <20250617-dma-buf-ecc-heap-v5-0-0abdc5863a4f@kernel.org> To: Rob Herring , Saravana Kannan , Sumit Semwal , Benjamin Gaignard , Brian Starkey , John Stultz , "T.J. Mercier" , =?utf-8?q?Christian_K=C3=B6nig?= , Krzysztof Kozlowski , Conor Dooley Cc: Andrew Davis , Jared Kangas , Mattijs Korpershoek , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, Maxime Ripard X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=2164; i=mripard@kernel.org; h=from:subject:message-id; bh=cGUtX2I1TX5Mw8HpaioqDUtXETjbLf4kkml849rWcMw=; b=owGbwMvMwCmsHn9OcpHtvjLG02pJDBmBcScDQ08LhRWeOOWxxC70UXuiE/+Gm/KtO60MXi++8 jfn7tn3HVNZGIQ5GWTFFFmeyISdXt6+uMrBfuUPmDmsTCBDGLg4BWAiyn2MDT945obO67y+iPtX 7l6Oz6v5Lv9r0HYQ3TV9V0HJ4ZunGn8s+sYWNuPEujDZaRyf9BhPpDDWaX8MiX9r0vHAt3hb0cT or54eV4SrWjYlc6fZ3lVbcPb7WyvhLYWCqUbt9Rsnf/l+i1sSAA== X-Developer-Key: i=mripard@kernel.org; a=openpgp; fpr=BE5675C37E818C8B5764241C254BCFC56BF6CE8D Some parts of the memory can be dedicated to specific purposes and exposed as a dedicated memory allocator. This is especially useful if that particular region has a particular properties the rest of the memory doesn't have. For example, some platforms have their entire RAM covered by ECC but for a small area meant to be used by applications that don't need ECC, and its associated overhead. Let's introduce a binding to describe such a region and allow the OS to create a dedicated memory allocator for it. Signed-off-by: Maxime Ripard --- .../bindings/reserved-memory/carved-out.yaml | 49 ++++++++++++++++++= ++++ 1 file changed, 49 insertions(+) diff --git a/Documentation/devicetree/bindings/reserved-memory/carved-out.y= aml b/Documentation/devicetree/bindings/reserved-memory/carved-out.yaml new file mode 100644 index 0000000000000000000000000000000000000000..9ab5d1ebd9ebd9111b7c064fabe= 1c45e752da83b --- /dev/null +++ b/Documentation/devicetree/bindings/reserved-memory/carved-out.yaml @@ -0,0 +1,49 @@ +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/reserved-memory/carved-out.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Carved-out Memory Region + +description: | + Specifies that the reserved memory region has been carved out of the + main memory allocator, and is intended to be used by the OS as a + dedicated memory allocator. + +maintainers: + - Maxime Ripard + +properties: + compatible: + const: carved-out + + reg: + description: region of memory that is carved out. + +allOf: + - $ref: reserved-memory.yaml + - not: + required: + - reusable + - not: + required: + - no-map + +required: + - compatible + - reg + +unevaluatedProperties: false + +examples: + - | + reserved-memory { + #address-cells =3D <1>; + #size-cells =3D <1>; + + memory@12340000 { + compatible =3D "carved-out"; + reg =3D <0x12340000 0x00800000>; + }; + }; --=20 2.49.0