[PATCH v4 3/3] dtc: Add support for variable sized elements

David Gibson david at gibson.dropbear.id.au
Wed Oct 12 01:44:13 EST 2011


On Tue, Sep 27, 2011 at 11:11:38AM -0700, Anton Staaf wrote:
> Elements of size 8, 16, 32, and 64 bits are supported.  The new
> /bits/ syntax was selected so as to not pollute the reserved
> keyword space with uint8/uint16/... type names.
> 
> With this patch the following property assignment:
> 
>     property = /bits/ 16 <0x1234 0x5678 0x0 0xffff>;
> 
> is equivalent to:
> 
>     property = <0x12345678 0x0000ffff>;
> 
> It is now also possible to directly specify a 64 bit literal in a
> cell list, also known as an array using:
> 
>     property = /bits/ 64 <0xdeadbeef00000000>;
> 
> It is an error to attempt to store a literal into an element that is
> too small to hold the literal, and the compiler will generate an
> error when it detects this.  For instance:
> 
>     property = /bits/ 8 <256>;
> 
> Will fail to compile.  It is also an error to attempt to place a
> reference in a non 32-bit element.
> 
> The documentation has been changed to reflect that the cell list
> is now an array of elements that can be of sizes other than the
> default 32-bit cell size.
> 
> The sized_cells test tests the creation and access of 8, 16, 32,
> and 64-bit sized elements.  It also tests that the creation of two
> properties, one with 16 bit elements and one with 32 bit elements
> result in the same property contents.
> 
> Signed-off-by: Anton Staaf <robotboy at chromium.org>

What the hell, I think I've convinced myself that /bits/ is good
enough.

Acked-by: David Gibson <david at gibson.dropbear.id.au>

-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson


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