Commit 2b9a31d7 authored by Rafał Miłecki's avatar Rafał Miłecki Committed by Miquel Raynal
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dt-bindings: mtd: partitions: support marking rootfs partition 



Linux needs to know what to use as root device. On embedded devices with
flash the only common way to specify that is cmdline & root= parameter.

That solution works with U-Boot which is Linux & cmdline aware but isn't
available with all market bootloaders. Also that method is fragile:
1. Requires specific probing order on multi-flash devices
2. Uses hardcoded partitions indexes

A lot of devices use different partitioning methods. It may be
"fixed-partitions" or some dynamic partitioning (e.g. based on parts
table). For such cases allow "linux,rootfs" property to mark correct
flash partition.

Signed-off-by: default avatarRafał Miłecki <rafal@milecki.pl>
Reviewed-by: default avatarRob Herring <robh@kernel.org>
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Link: https://lore.kernel.org/linux-mtd/20221022211318.32009-1-zajec5@gmail.com
parent 895d68a3

Documentation/devicetree/bindings/mtd/partitions/fixed-partitions.yaml

+1 −0
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ examples: 
        partition@0 {

            label = "filesystem";

            reg = <0x00000000 0x1 0x00000000>;

            linux,rootfs;

        };

    };

Documentation/devicetree/bindings/mtd/partitions/partition.yaml

+4 −0
Original line number Diff line number Diff line
@@ -52,6 +52,10 @@ properties: 
      immune to paired-pages corruptions

    type: boolean



  linux,rootfs:

    description: Marks partition that contains root filesystem to mount and boot

      user space from



if:

  not:

    required: [ reg ]