From nobody Sun Feb 8 16:24:10 2026 Received: from smtpout-03.galae.net (smtpout-03.galae.net [185.246.85.4]) (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 1B3493859EC for ; Thu, 29 Jan 2026 12:09:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.85.4 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769688597; cv=none; b=bSBobAvGBGv9/j+1KsZtyl0RsyByBL+YY6qa9XZ2VhhbIS/lYaDGtOGCUPbm2jb/AmiydBXNyPZoZ/jGckCDDnX9H8SBf+6Mdm+k/Ga6672y2HEfGkNDMk0Da3zp47YXRJxLZKsmgrW0jQnv9Sbp1tXi5dDOB2wDUJNJHWLUdE8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769688597; c=relaxed/simple; bh=FlM6rXbq/a3tXf7u87GfSIuIuD1VH5jijbe21pOb8jg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=qIVbrc0v+DaAWMgHNTTMLtRkmxR6jzWxZjmSNVnOJyaKrQGVsE2EM5jvwXnvUYTiUjqJCwkdOuz6NXLMwoao+J/2+cdbquuPBngvOvOOQGvSKUwYTMXC9l+60pRd9CXTL7bh30m6Juqe9L6WLADzTh41G21RQ1ozpgPTWOY7ZjY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=DIXXMNMw; arc=none smtp.client-ip=185.246.85.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="DIXXMNMw" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id 800B74E42317; Thu, 29 Jan 2026 12:09:53 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 56084606B6; Thu, 29 Jan 2026 12:09:53 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 36679119A884D; Thu, 29 Jan 2026 13:09:50 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1769688591; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=oYbdI2fsKaGTvEp6wqBhR2QgtSukXpWA3HhYALr0rC8=; b=DIXXMNMwjiOwbhuSitndltWIqs1OunowrNs18VXBxNmEjreeGNHAsd1hx/xnmWylTNXyaH WtWsWNn6pUosl3uYUb3Jf7kuuyX19IAJNYxzAUxsjUsmCgGIr73tlKBY4VDKxZ0/bhV6Zt s54C5EHAHHsgOSQXDeFQmGbEoxYyS/qFBfhMb4PkVUbJQJ+GVRxaY1fVM7bv9F1L4/3B1/ ezwUPcFKuL5hjV7n71o9snOAxY7JWHPKOk7NCOG2Nk99R4PWmJ4F/6kihjBldL1Um39PVS v1U93VjMuZnYWX6D4B314jMP7A1miYNQYBqbjMZ/9lHNbsGvCTf22bEIAJ0a0g== From: Luca Ceresoli Date: Thu, 29 Jan 2026 13:09:27 +0100 Subject: [PATCH v15 1/3] dt-bindings: mtd: Describe MTD partitions concatenation 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: <20260129-mtd-virt-concat-v15-1-c56a232efbd2@bootlin.com> References: <20260129-mtd-virt-concat-v15-0-c56a232efbd2@bootlin.com> In-Reply-To: <20260129-mtd-virt-concat-v15-0-c56a232efbd2@bootlin.com> To: Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Rob Herring , Krzysztof Kozlowski , Conor Dooley , =?utf-8?q?Rafa=C5=82_Mi=C5=82ecki?= Cc: Amit Kumar Mahapatra , Michal Simek , Bernhard Frauendienst , Thomas Petazzoni , linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Luca Ceresoli X-Mailer: b4 0.14.3 X-Last-TLS-Session-Version: TLSv1.3 From: Amit Kumar Mahapatra The AMD QSPI controller supports an advanced connection modes called Stacked mode which allow the controller to treat two different flashes as one storage. In Stacked connection mode flashes share the same SPI bus, but different CS line, controller driver asserts the CS of the flash to which it needs to communicate. Stacked mode is a software abstraction rather than a controller feature or capability. At any given time, the controller communicates with one of the two connected flash devices, as determined by the requested address and data length. If an operation starts on one flash and ends on the other, the mtd layer needs to split it into two separate operations and adjust the data length accordingly. For more information on the modes please feel free to go through the controller flash interface below [1]. To support stacked mode, the existing MTD concat driver has been extended to be more generic, enabling multiple sets of MTD partitions to be virtually concatenated, with each set forming a distinct logical MTD device. A new Device Tree property is introduced to facilitate this, containing phandles of the partitions to be concatenated with the one where the property is defined. This approach supports multiple sets of concatenated partitions. [1] https://docs.amd.com/r/en-US/am011-versal-acap-trm/QSPI-Flash-Device-In= terface Suggested-by: Miquel Raynal Suggested-by: Rob Herring Signed-off-by: Amit Kumar Mahapatra Reviewed-by: Rob Herring (Arm) --- .../bindings/mtd/partitions/partition.yaml | 20 ++++++++++++++++= ++++ 1 file changed, 20 insertions(+) diff --git a/Documentation/devicetree/bindings/mtd/partitions/partition.yam= l b/Documentation/devicetree/bindings/mtd/partitions/partition.yaml index 80d0452a2a33..c9aba6838b3c 100644 --- a/Documentation/devicetree/bindings/mtd/partitions/partition.yaml +++ b/Documentation/devicetree/bindings/mtd/partitions/partition.yaml @@ -57,6 +57,15 @@ properties: user space from type: boolean =20 + part-concat-next: + description: List of phandles to MTD partitions that need be concatena= ted + with the current partition. + $ref: /schemas/types.yaml#/definitions/phandle-array + minItems: 1 + maxItems: 16 + items: + maxItems: 1 + align: $ref: /schemas/types.yaml#/definitions/uint32 minimum: 2 @@ -138,4 +147,15 @@ examples: reg =3D <0x200000 0x100000>; align =3D <0x4000>; }; + + part0: partition@400000 { + part-concat-next =3D <&part1>; + label =3D "part0_0"; + reg =3D <0x400000 0x100000>; + }; + + part1: partition@800000 { + label =3D "part0_1"; + reg =3D <0x800000 0x800000>; + }; }; --=20 2.52.0