Re: [PATCH 0/3] Extend dtc with data type handling

On Fri, Dec 13, 2013 at 05:49:09PM +0100, Tomasz Figa wrote:

This series intends to extend dtc with appropriate infrastructure
to handle property data types. First, dtc is modified to preserve
type information when parsing DTS. Then type guessing is implemented
for flat and fs trees where type data is not available. After that,
DTS generation code is modified to use only type information when
printing property data.

Hrm.  I think this is completely backwards to the right approach.

For dt checking what we want is a schema.  That can specify datatypes
amongst other constraints, but in the end you can check the actual
bytes of the DT against the constraints imposed by the schema,
regardless of how those bytes are presented to the checker.

By adding type information to the in-flight tree you're checking not
the actual content of the DT, but how you've chosen to express that
information in DTS format.

More concretely, we should be able to schema-check trees in binary
format, not just source.  With these patches that will fail if -I dtb
makes the wrong type guesses.

Effect of this is the ability to implement checks for data types
of properties. Also, as a side effect, it's now possible to do
almost 1:1 dts <=> dts passes (not very useful, but shows that
things are working well).

Tomasz Figa (3):
  dtc: Keep type information from DTS
  dtc: Inject guessed type information in case of flat and fs trees
  dtc: Use type information when printing tree source

 data.c       |  62 +++++++++++++++++++++++-
 dtc-parser.y |  47 ++++++++++++++-----
 dtc.h        |  12 +++++
 flattree.c   |   2 +-
 fstree.c     |   6 ++-
 livetree.c   |  16 +++++--
 treesource.c | 150 +++++++++++++++++++++++++++++++++--------------------------
 7 files changed, 209 insertions(+), 86 deletions(-)

-- 
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