From nobody Thu Jan 1 07:18:50 2026 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6058FC25B6B for ; Wed, 25 Oct 2023 05:30:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230221AbjJYFaB (ORCPT ); Wed, 25 Oct 2023 01:30:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229456AbjJYF37 (ORCPT ); Wed, 25 Oct 2023 01:29:59 -0400 Received: from smtp161.vfemail.net (smtp161.vfemail.net [146.59.185.161]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 694FF129 for ; Tue, 24 Oct 2023 22:29:57 -0700 (PDT) Received: (qmail 19215 invoked from network); 25 Oct 2023 05:29:55 +0000 Received: from localhost (HELO nl101-3.vfemail.net) () by smtpout.vfemail.net with ESMTPS (ECDHE-RSA-AES256-GCM-SHA384 encrypted); 25 Oct 2023 05:29:55 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=simple; d=openmail.cc; h=from:to:cc :subject:date:message-id:mime-version:content-transfer-encoding; s=2018; bh=z3I7BxJWkJGWMcauhe7x+lldOe3CDXrLlKAqfautbjk=; b=Cj0w JoiKI2SfVe60Psj61dy+q52zcpnQMkdZP67tcjvidMl6y4aVKYAxOW9ExxIhthqS 15sVmRPwMBR84z2XcNUVvQqdEyyp9sFp+j0qboyt7AAZE+D8/KT0vEQxB9QjsgpH x40Gly4ZsBpym5DXJCFTEPOtAY8Q2S0TY5UftTo= Received: (qmail 25396 invoked from network); 25 Oct 2023 05:29:55 -0000 Received: by simscan 1.4.0 ppid: 25167, pid: 25355, t: 1.2316s scanners:none Received: from unknown (HELO bmwxMDEudmZlbWFpbC5uZXQ=) (ZXF1dUBvcGVubWFpbC5jYw==@MTkyLjE2OC4xLjE5Mg==) by nl101.vfemail.net with ESMTPA; 25 Oct 2023 05:29:54 -0000 From: Edward Chow To: Rob Herring , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra , Krzysztof Kozlowski Cc: linux-mtd@lists.infradead.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Edward Chow Subject: [PATCH] dt-bindings: mtd-partitions: Export special values Date: Wed, 25 Oct 2023 13:29:37 +0800 Message-ID: <20231025052937.830813-1-equu@openmail.cc> X-Mailer: git-send-email 2.42.0 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" There are special "offset" and "size" values defined and documented in linux/mtd/partitions.h: // consume as much as possible, leaving size after the end of partition. // the partition will start at the next erase block. // the partition will start where the previous one ended. (Though not explicitly, they are compared against variables in uint64_t in drivers/mtd/mtdpart.c, so they had better be considered as such.) // the partition will extend to the end of the master MTD device. These special values could be used to define partitions automatically fitting to the size of the master MTD device at runtime. However, these values used not to be exported to dt-bindings, thus seldom used before, since they might have been only used in numeric form, such as "(-1) (-3)" for MTDPART_OFS_RETAIN. Now, they are exported in dt-bindings/mtd/partitions.h as 32-bit cell values, so 2-cell addressed should be defined to use special offset values, such as "MTDPART_OFS_SPECIAL MTDPART_OFS_RETAIN" for MTDPART_OFS_RETAIN in linux/mtd/partitions.h. An example is added to fixed-partitions.yaml. Signed-off-by: Edward Chow --- .../mtd/partitions/fixed-partitions.yaml | 29 +++++++++++++++++++ MAINTAINERS | 2 ++ include/dt-bindings/mtd/partitions.h | 15 ++++++++++ 3 files changed, 46 insertions(+) create mode 100644 include/dt-bindings/mtd/partitions.h diff --git a/Documentation/devicetree/bindings/mtd/partitions/fixed-partiti= ons.yaml b/Documentation/devicetree/bindings/mtd/partitions/fixed-partition= s.yaml index 331e564f29dc..a939fb52ef76 100644 --- a/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml +++ b/Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml @@ -164,3 +164,32 @@ examples: read-only; }; }; + + - | + partitions { + compatible =3D "fixed-partitions"; + #address-cells =3D <2>; + #size-cells =3D <1>; + + partition@0 { + label =3D "bootloader"; + reg =3D <0 0x000000 0x020000>; + read-only; + }; + + firmware@1 { + label =3D "firmware"; + /* From the end of the last partition, occupying as mush + * as possible, retaining 0x010000 after it, + * "MTDPART_OFS_SPECIAL MTDPART_OFS_NXTBLK" similar to + * this, but always beginning at erase block boundary. */ + reg =3D ; + }; + + calibration@2 { + compatible =3D "fixed-partitions"; + label =3D "calibration"; + /* Appending to the last partition, occupying 0x010000 */ + reg =3D ; + }; + }; diff --git a/MAINTAINERS b/MAINTAINERS index 668d1e24452d..7d6beadc8b36 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -13771,9 +13771,11 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/g= it/mtd/linux.git mtd/fixes T: git git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux.git mtd/next F: Documentation/devicetree/bindings/mtd/ F: drivers/mtd/ +F: include/dt-bindings/mtd/ F: include/linux/mtd/ F: include/uapi/mtd/ =20 + MEMSENSING MICROSYSTEMS MSA311 DRIVER M: Dmitry Rokosov L: linux-iio@vger.kernel.org diff --git a/include/dt-bindings/mtd/partitions.h b/include/dt-bindings/mtd= /partitions.h new file mode 100644 index 000000000000..456a54a1259a --- /dev/null +++ b/include/dt-bindings/mtd/partitions.h @@ -0,0 +1,15 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Device Tree constants identical to those in include/linux/mtd/partition= s.h + */ + +#ifndef _DT_BINDINGS_MTD_PARTITIONS_H +#define _DT_BINDINGS_MTD_PARTITIONS_H + +#define MTDPART_OFS_SPECIAL (-1) +#define MTDPART_OFS_RETAIN (-3) +#define MTDPART_OFS_NXTBLK (-2) +#define MTDPART_OFS_APPEND (-1) +#define MTDPART_SIZ_FULL (0) + +#endif --=20 2.42.0