Defining schemas for Device Tree
Stephen Warren
swarren at wwwdotorg.org
Tue Jul 30 14:25:42 EDT 2013
On 07/30/2013 12:04 PM, jonsmirl at gmail.com wrote:
...
> So what does an alternating use of strings do?
>
> dmas = "tx", <&pdma0 7>, "rx", <&pdma0 6>;
cat > temp.dts << ENDOFHERE
/dts-v1/;
/ {
dmas = "tx", <&pdma0 7>, "rx", <&pdma0 6>;
pdma0: dma { };
};
ENDOFHERE
dtc -O dtb -o temp.dtb -I dts temp.dts
hexdump -C temp.dtb
yields:
> 00000000 d0 0d fe ed 00 00 00 ab 00 00 00 38 00 00 00 98 |...........8....|
> 00000010 00 00 00 28 00 00 00 11 00 00 00 10 00 00 00 00 |...(............|
> 00000020 00 00 00 13 00 00 00 60 00 00 00 00 00 00 00 00 |.......`........|
> 00000030 00 00 00 00 00 00 00 00 00 00 00 01 00 00 00 00 |................|
> 00000040 00 00 00 03 00 00 00 16 00 00 00 00 74 78 00 00 |............tx..|
ss ss ss pp
> 00000050 00 00 01 00 00 00 07 72 78 00 00 00 00 01 00 00 |.......rx.......|
pp pp pp ii ii ii ii ss ss ss pp pp pp pp ii ii
> 00000060 00 06 00 00 00 00 00 01 64 6d 61 00 00 00 00 03 |........dma.....|
ii ii
... where ss represents a string byte, pp a phandle byte, ii an integer
byte.
> 00000070 00 00 00 04 00 00 00 05 00 00 00 01 00 00 00 03 |................|
> 00000080 00 00 00 04 00 00 00 0b 00 00 00 01 00 00 00 02 |................|
> 00000090 00 00 00 02 00 00 00 09 64 6d 61 73 00 6c 69 6e |........dmas.lin|
> 000000a0 75 78 2c 70 68 61 6e 64 6c 65 00 |ux,phandle.|
Starting about half way through that last line is the string table.
(the string table indirection is for property names, not property
values, and it looks like not for node names either)
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