[PATCH V2 1/2] dt-bindings: mtd: explicitly document nesting partitions descriptions

[boris.brezillon@xxxxxxxxxxx (Boris Brezillon)]

On Fri, 13 Jul 2018 16:32:20 +0200
Rafa? Mi?ecki <zajec5 at gmail.com> wrote:

> From: Rafa? Mi?ecki <rafal at milecki.pl>
> 
> Documentation was already saying that fixed and dynamic partitioning can
> be mixed but was missing a clear description and examples. This commit
> adds a proper documentation of how descriptions can be nested and how
> layouts can be mixed.
> 
> This addition is important for partitions that contain subpartitions.
> In such cases partitions have to be properly described in order to let
> system handle them correctly.
> 
> Depending on situation, nesting descriptions may provide more accurate
> logic/structure and/or allow mixing partitioning types (various
> "compatible" values).
> 
> Signed-off-by: Rafa? Mi?ecki <rafal at milecki.pl>

Applied both patches.

Thanks,

Boris

> ---
> V2: Rewrote example: I can include "brcm,trx" now as its Documentation
>     has been pushed into mtd git tree.
>     Updated commit message.
> ---
>  .../devicetree/bindings/mtd/partition.txt          | 46 ++++++++++++++++++++++
>  1 file changed, 46 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt
> index a8f382642ba9..afbbd870496d 100644
> --- a/Documentation/devicetree/bindings/mtd/partition.txt
> +++ b/Documentation/devicetree/bindings/mtd/partition.txt
> @@ -14,6 +14,13 @@ method is used for a given flash device. To describe the method there should be
>  a subnode of the flash device that is named 'partitions'. It must have a
>  'compatible' property, which is used to identify the method to use.
>  
> +When a single partition is represented with a DT node (it depends on a used
> +format) it may also be described using above rules ('compatible' and optionally
> +some extra properties / subnodes). It allows describing more complex,
> +hierarchical (multi-level) layouts and should be used if there is some
> +significant relation between partitions or some partition internally uses
> +another partitioning method.
> +
>  Available bindings are listed in the "partitions" subdirectory.
>  
>  
> @@ -109,3 +116,42 @@ flash at 2 {
>  		};
>  	};
>  };
> +
> +flash at 3 {
> +	partitions {
> +		compatible = "fixed-partitions";
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +
> +		partition at 0 {
> +			label = "bootloader";
> +			reg = <0x000000 0x100000>;
> +			read-only;
> +		};
> +
> +		firmware at 100000 {
> +			label = "firmware";
> +			reg = <0x100000 0xe00000>;
> +			compatible = "brcm,trx";
> +		};
> +
> +		calibration at f00000 {
> +			label = "calibration";
> +			reg = <0xf00000 0x100000>;
> +			compatible = "fixed-partitions";
> +			ranges = <0 0xf00000 0x100000>;
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +
> +			partition at 0 {
> +				label = "wifi0";
> +				reg = <0x000000 0x080000>;
> +			};
> +
> +			partition at 80000 {
> +				label = "wifi1";
> +				reg = <0x080000 0x080000>;
> +			};
> +		};
> +	};
> +};