From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= Subject: [PATCH V2 1/4] dt-bindings: mtd: make partitions doc a bit more generic Date: Mon, 24 Apr 2017 14:41:17 +0200 Message-ID: <20170424124120.31613-2-zajec5@gmail.com> References: <20170420135731.13272-2-zajec5@gmail.com> <20170424124120.31613-1-zajec5@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20170424124120.31613-1-zajec5-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: David Woodhouse , Brian Norris , Boris Brezillon , Marek Vasut , Richard Weinberger , Cyrille Pitchen Cc: Rob Herring , Mark Rutland , Frank Rowand , Linus Walleij , linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Geert Uytterhoeven , Jonas Gorski , =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= List-Id: devicetree@vger.kernel.org From: Brian Norris Currently the only documented partitioning is "fixed-partitions" but there are more methods in use that we may want to support in the future. Mention them and make it clear Fixed Partitions are just a single case. Signed-off-by: Brian Norris Signed-off-by: Rafał Miłecki --- This is based on Brian's patch: [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding V1: Dropped "Section B: On-Flash Partition Tables" with Google's FMAP as this patchset doesn't add that new parser. V2: Add "We currently only document a binding for fixed layouts." part --- .../devicetree/bindings/mtd/partition.txt | 30 +++++++++++++++++----- 1 file changed, 24 insertions(+), 6 deletions(-) diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt index 81a224da63be..b5de311b967a 100644 --- a/Documentation/devicetree/bindings/mtd/partition.txt +++ b/Documentation/devicetree/bindings/mtd/partition.txt @@ -1,29 +1,47 @@ -Representing flash partitions in devicetree +Flash partitions in device tree +=============================== -Partitions can be represented by sub-nodes of an mtd device. This can be used +Flash devices can be partitioned into one or more functional ranges (e.g. "boot +code", "nvram", "kernel"). + +Different devices may be partitioned in a different ways. Some may use a fixed +flash layout set at production time. Some may use on-flash table that describes +the geometry and naming/purpose of each functional region. It is also possible +to see these methods mixed. + +To assist system software in locating partitions, we provide a binding to +describe which method is used for a given flash. + +We currently only document a binding for fixed layouts. + + +Fixed Partitions +================ + +Partitions can be represented by sub-nodes of a flash device. This can be used on platforms which have strong conventions about which portions of a flash are used for what purposes, but which don't use an on-flash partition table such as RedBoot. -The partition table should be a subnode of the mtd node and should be named +The partition table should be a subnode of the flash node and should be named 'partitions'. This node should have the following property: - compatible : (required) must be "fixed-partitions" Partitions are then defined in subnodes of the partitions node. -For backwards compatibility partitions as direct subnodes of the mtd device are +For backwards compatibility partitions as direct subnodes of the flash device are supported. This use is discouraged. NOTE: also for backwards compatibility, direct subnodes that have a compatible string are not considered partitions, as they may be used for other bindings. #address-cells & #size-cells must both be present in the partitions subnode of the -mtd device. There are two valid values for both: +flash device. There are two valid values for both: <1>: for partitions that require a single 32-bit cell to represent their size/address (aka the value is below 4 GiB) <2>: for partitions that require two 32-bit cells to represent their size/address (aka the value is 4 GiB or greater). Required properties: -- reg : The partition's offset and size within the mtd bank. +- reg : The partition's offset and size within the flash Optional properties: - label : The label / name for this partition. If omitted, the label is taken -- 2.11.0 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html