On Tue, Jun 07, 2016 at 01:49:59PM -0700, Frank Rowand wrote:
> From: Frank Rowand <frank.rowand@xxxxxxxxxxx>
>
> Add items to Devicetree Source Format chapter
>
> - Add naming convention for DTS files and DTS include files
> - Add /include/ compiler directive
> - Add ";" to end of node definition
> - Add /delete-node/ and /delete-property/
> - Add arithmetic, bitwise, logical, and ternary expressions
>
> Note that cpp directives are not included in this patch, and
> are not yet specified in this appendix.
>
> Signed-off-by: Frank Rowand <frank.rowand@xxxxxxxxxxx>
> ---
>
> changes in v2
> - arithmetic operators "and", "or" were incorrectly listed as as bitwise
> - thus bitwise operators "and", "or" were incorrectly shown
> - "exclusive or" operator added
> - logical and arithmetic "not" operators added
> - ternary operator added
> - moved shift operators from arithmetic to bitwise
>
>
> source/source-language.rst | 70 ++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 69 insertions(+), 1 deletion(-)
>
> Index: b/source/source-language.rst
> ===================================================================
> --- a/source/source-language.rst
> +++ b/source/source-language.rst
> @@ -9,6 +9,19 @@ devicetree in the form expected by the k
> not a formal syntax definition of DTS, but describes the basic
> constructs used to represent devicetrees.
>
> +The name of DTS files should end with ".dts".
> +
> +Compiler directives
> +-------------------
> +
> +Other source files can be included from a DTS file. The name of include
> +files should end with ".dtsi". Included files can in turn include
> +additional files.
> +
> +::
> +
> + /include/ "FILE"
> +
> Node and property definitions
> -----------------------------
>
> @@ -21,11 +34,18 @@ preceded by a label.
> [label:] node-name[@unit-address] {
> [properties definitions]
> [child nodes]
> - }
> + };
>
> Nodes may contain property definitions and/or child node definitions. If
> both are present, properties shall come before child nodes.
>
> +Previously defined nodes may be deleted.
> +
> +::
> +
> + /delete-node/ node-name;
> + /delete-node/ &label;
> +
> Property definitions are name value pairs in the form:
>
> ::
> @@ -39,6 +59,12 @@ form:
>
> [label:] property-name;
>
> +Previously defined properties may be deleted.
> +
> +::
> +
> + /delete-property/ property-name;
> +
> Property values may be defined as an array of 32-bit integer cells, as
> null-terminated strings, as bytestrings or a combination of these.
>
> @@ -48,6 +74,48 @@ null-terminated strings, as bytestrings
> ::
>
> interrupts = <17 0xc>;
> +- values may be represented as arithmetic, bitwise, or logical expressions
> + within parenthesis.
> +
> +::
> +
> + Arithmetic operators
> +
> + + add
> + - subtract
> + * multiply
> + / divide
> +
> +::
> +
> + Bitwise operators
> +
> + & and
> + | or
> + ^ exclusive or
> + ~ not
> + << left shift
> + >> right shift
> +
> +::
> +
> + Logical operators
> +
> + < less than
> + > greater than
> + <= less than or equal
> + >= greater than or equal
> + == equal
> + != not equal
> + && and
> + || or
> + ! not
Fwiw, I think &&, || and ! usually get classified as "logical
operators" but <, > etc. get classified as "relational operators"
rather than putting them in the same category.
Hrm.. given that you're listing them all here, I wonder if it would
make sense to do so in precedence order (should be the same as for C).
> +::
> +
> + Ternary operators
> +
> + ?: (condition ? value_if_true : value_if_false)
>
> - A 64-bit value is represented with two 32-bit cells. Example:
>
>
--
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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