Re: [PATCH] Open Firmware device tree virtual filesystem

From: Segher Boessenkool
Date: Sun Dec 31 2006 - 22:39:57 EST

+A regular file in ofwfs contains the exact byte sequence that
+comprises the OFW property value. Properties are not reformatted
+into text form, so numeric property values appear as binary
+integers. While this is inconvenient for viewing, it is generally
+easier for programs that read property values, and it means that
+Open Firmware documentation about property values applies
+directly, without having to separately document an ASCII
+transformation (which would have to separately specified for
+different kinds of properties).

I appreciate the ASCII formatting that openpromfs currently does.

The text representation (in openpromfs) is *useless*, since it cannot
be transformed back into the binary representation.

Most tools have an easier time using the raw binary version too.
If a user wants to see text, they can use an "lsdevtree" program.

Perhaps, should OFWFS be used, it could offer both?

Such transformations don't belong in the kernel but in userland.

+The recommended mount point for ofwfs is /ofw. (TBD: Should it be
+mounted somewhere under /sys instead?)

Somewhere in /sys/firmware perhaps.

While I hate deep paths, /sys/firmware/device-tree does sound good.


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