Re: [PATCH 1/3] ARM: dts: Add headers with constants for MTD partitions

[Stephen Warren <swarren@wwwdotorg.org>]

On 06/11/2013 08:48 AM, Florian Vaussard wrote:
> These constants can be used to easily declare MTD partitions inside
> DTS.
> 
> The constants MTDPART_OFS_* are purposely not included. Indeed,
> parse_ofpart_partitions() is expecting u64, but a DT cell is u32.
> Negative constants, as defined by MTDPART_OFS_*, would be wrongly
> interpreted by parse_ofpart_partitions(). Two cells should be
> used to correctly encode the negative constants, but this breaks
> current usage.

I think addition of common headers like this needs an ack from
Grant/Rob. I CC'd them here.

> diff --git a/include/dt-bindings/mtd/partitions.h b/include/dt-bindings/mtd/partitions.h

> + * This header provides constants used with MTD partitions.
...
> +/* Partition size */
> +#define MTDPART_SIZ_FULL	0

Which binding document in Documentation/devicetree/bindings is this
definition associated with? The comment above should really mention
this. Documentation/devicetree/bindings/mtd/partition.txt doesn't seem
to mention this value.

> diff --git a/include/dt-bindings/sizes.h b/include/dt-bindings/sizes.h

...
> +#define SZ_1G				0x40000000
> +#define SZ_2G				0x80000000
> +
> +#endif

For MTD partitions specifically, SZ_4G and onwards would be useful in
theory, although that would end up putting two cell values into a single
macro. and then the values couldn't be added/or'd together. So, I'm not
really sure if we want to add those larger values, but food for thought...