From nobody Mon Feb 9 08:56:13 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 EE181325488 for ; Tue, 3 Feb 2026 20:40:12 +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=1770151214; cv=none; b=MvHmui7ICPO55t+biAE2URuoBWDwmFYUoQZpq+ecxlY4O2xPZVVuvRSPQkz0LUi7cI+rvyksgjWM1f2IqmklkUe9IZooJSyd6bUrwKZmwJX/4fECGjuzr3nhONvE+Q/iU8GzATKipzdRRBQLOVqNYCpNfZzdlv6oJ9t1Rxl17y4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770151214; c=relaxed/simple; bh=FlM6rXbq/a3tXf7u87GfSIuIuD1VH5jijbe21pOb8jg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=namtQOhaxr5NGX30QB3ZFx7X2cWQKqPpM18EVlluqzUiCUah7Gl/mkWsLFF+DpUiuX7weclbigKwjU8o1TYFV4IOWA6L/RAG1cdDQVKnr3cgEf7zrNTRZneQvYYf8wfQAle/8IL5lZtuSjqxI76ENKJlcjyu+U8KB4gQRNQHoGU= 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=Uv10Bqx9; 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="Uv10Bqx9" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id B211B4E423E3; Tue, 3 Feb 2026 20:40:11 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 89E7260728; Tue, 3 Feb 2026 20:40:11 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 2ACDB119A8891; Tue, 3 Feb 2026 21:40:09 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1770151210; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=oYbdI2fsKaGTvEp6wqBhR2QgtSukXpWA3HhYALr0rC8=; b=Uv10Bqx9uJPdFQaxT4nFxHJOG2Nfr3yJMVV0RDRRbd+lgJiFlD1rbPjET47gHEc6PAn7hF IQKc5UOQyE5hxDAt3qpYCOG4IblIOx8JJG4/RfxxetEPqT1AhTEV+HjNT/nqKbQYOPbXrx 2CqGYKF3J1BtSNQPSn08SJhAo8vX6Ab7A6i6MCuYnOxuWVIiKP5nfKV3Y3LFERANBN5Uw4 IQCS5h8jK8YgagM+57Z8iZughXGA4QwqsYSrACilLR7oGq0+7iBIg4+HDkbEv0lp4IwukB pe+WBWdv7ytjkt9v2BePwwCqZVPpL16mBIapJHe8/ZKHkhm3y1EAByZ7ISi98w== From: Luca Ceresoli Date: Tue, 03 Feb 2026 21:39:57 +0100 Subject: [PATCH v16 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: <20260203-mtd-virt-concat-v16-1-a112a979c813@bootlin.com> References: <20260203-mtd-virt-concat-v16-0-a112a979c813@bootlin.com> In-Reply-To: <20260203-mtd-virt-concat-v16-0-a112a979c813@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