From eff2ebd207af9f501af0ef667a7d14befcb36c1b Mon Sep 17 00:00:00 2001 From: David Gibson Date: Thu, 28 Jun 2007 15:56:26 +1000 Subject: [POWERPC] In booting-without-of.txt, clarify that properties must precede subnodes A strict reading of the flattened device tree format defined in booting-without-of.txt does in fact require that all the tags defining properties for a node go before any definitions of subnodes, however it's not particularly emphasised. Although allowing intermingled properties and subnodes would not be ambiguous in meaning, the kernel parser does currently require that properties precede subnodes. Furthermore, keeping this constraint makes life easier for various device tree scanning tools. Therefore, re-emphasise in booting-without-of.txt that this is a strict requirement of the flattened device tree format. Signed-off-by: David Gibson Signed-off-by: Paul Mackerras --- Documentation/powerpc/booting-without-of.txt | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'Documentation') diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt index d42d98107d4..c169299716b 100644 --- a/Documentation/powerpc/booting-without-of.txt +++ b/Documentation/powerpc/booting-without-of.txt @@ -626,6 +626,14 @@ So the node content can be summarized as a start token, a full path, a list of properties, a list of child nodes, and an end token. Every child node is a full node structure itself as defined above. +NOTE: The above definition requires that all property definitions for +a particular node MUST precede any subnode definitions for that node. +Although the structure would not be ambiguous if properties and +subnodes were intermingled, the kernel parser requires that the +properties come first (up until at least 2.6.22). Any tools +manipulating a flattened tree must take care to preserve this +constraint. + 4) Device tree "strings" block In order to save space, property names, which are generally redundant, -- cgit v1.2.3