dtlib get_node does not follow dts spec

[kylebonnici]

Describe the bug

get_node("/interrupt-map-bitops-test/node@70000000e") should be equal to get_node("/interrupt-map-bitops-test/node@70000000E") this bug created the issue #103638

Looking at dtlib is seams that is also does not consider this case from the spec https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#path-names as address can also be omitted if path is unambiguous

e.g.

/ {
foo@10 {};
}

both paths -> /foo and /foo@10 should work. looking at scripts/dts/python-devicetree/src/devicetree/dtlib.py the fill name in full with address is always used and this is not correct.

Regression

• This is a regression.

Steps to reproduce

See #103638

Relevant log output

Impact

Annoyance – Minor irritation; no significant impact on usability or functionality.

Environment

No response

Additional Context

No response

[decsny]

If I am understanding the issue correctly, we have dtlib written so that hex values in unit addresses are case sensitive? I cannot tell from the DT spec if hex values in unit addresses are meant to be case sensitive or not, but I would personally expect them to be case insensitive. Unless I am just missing something, perhaps this question needs to be raised to the DT spec upstream itself and not just talked about within the confines of Zephyr. Also, I would suggest we change our tooling to make unit addresses case insensitive in the meantime, or normalize uppercase addresses to lowercase, if there are no other ramifications to doing that..

[kylebonnici]

IMO the spec is clear about the case insensitivity. The node address must be match the reg value see https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#node-name-requirements

The unit-address must match the first address specified in the reg property of the node.

reg property is a prop-encoded array and by definition. reg = <0xA> or reg = <0xa> are the same. hence Both foo@a and foo@A are the same.

The spec also make it clear that node address can be omitted from node path if not unambiguous see https://devicetree-specification.readthedocs.io/en/latest/chapter2-devicetree-basics.html#path-names

A unit address may be omitted if the full path to the node is unambiguous.

e.g.

/ {
foo@10 {};
}

both paths -> /foo and /foo@10 should work. looking at scripts/dts/python-devicetree/src/devicetree/dtlib.py the fill name in full with address is always used and this is not correct.

Summary:

• Node name address part should be case insensitve
• Accessing a node by path must also work when node address is omitted when context has unambiguous node names

[rruuaanng]

soc {
  uart@2f8 { };
};

/soc/uart@2f8

Now

set = {
  'uart@3f8': <Node /soc/uart@3f8 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'hpet@fed00000': <Node /soc/hpet@fed00000 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'rtc@70': <Node /soc/rtc@70 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>
}

e.g.: set['uart'], ignoring @reg causes the target to be lost.

Require

{
  'uart@3f8': <Node /soc/uart@3f8 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'uart@2f8': <Node /soc/uart@2f8 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'hpet@fed00000': <Node /soc/hpet@fed00000 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'rtc@70': <Node /soc/rtc@70 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>

  'hpet': <Node /soc/hpet@fed00000 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'rtc': <Node /soc/rtc@70 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>
}

If there's only one uart available, then the build target should look like this:

  'uart@3f8': <Node /soc/uart@3f8 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,
  'uart': <Node /soc/uart@3f8 in 'D:/Code/github/zephyr/zephyr-test/zephyr/misc/empty_file.c'>,

So, we just need to change how the Node.nodes dictionary is built.

[kylebonnici]

@rruuaanng and node addresses has to be case insensitive so both set['uart@3f8'] and set['uart@3F8'] return the same value