Hi, I've run a comparison between OLPC's old OFW code (which mounts the device-tree at /ofw, and makes use of the sparc code) versus the code which I'm planning to send upstream (which mounts the device-tree at /proc/device-tree, and makes use of PROC_DEVTREE). The results are here:
http://dev.queued.net/~dilinger/dt.diff That's from running: find /proc/device-tree -type f | sort | while read f; do echo $f | sed 's#/proc/device-tree##'; sudo od -c $f; done > ~/dt-proc find /ofw -type f | sort | while read f; do echo $f | sed 's#/ofw##'; sudo od -c $f; done > ~/dt-ofw diff -u dt-ofw dt-proc > dt.diff Note that this was run on two different OLPC XO-1 machines, hence the difference in serial numbers, mfg-data, and other such things. There are two things I'm concerned about; the first is that device names are mangled. For some things (ie, "/batt...@0/name" => "/battery/name"), I don't particularly care; for others ("/pci/au...@f,3/device-id" => "/pci/audio/device-id"), it's kind of annoying to lose that extra bit of information. What's the purpose being the mangling that happens w/ /proc/device-tree? I the following comment in proc_devtree.c: * For a node with a name like "g...@10", we make symlinks called "gc" * and "@10" to it. However, I'm not seeing *any* symlinks at all in /proc/device-tree. My second concern is the renaming of /pci/u...@f,4 (the ohci device) to /pci/usb. I'm not sure if that's due to a bug in the devtree code, OFW, or my patch. Note that the kernel spits out the following messages while populating /proc/device-tree: [ 0.130869] device-tree: Duplicate name in /pci, renamed to "usb#1" [ 0.131589] device-tree: Duplicate name in /, renamed to "dropin-fs#1" I'm assuming that the code first renamed the ohci device from /pci/u...@f,4 to /pci/usb, attempted to then rename the wireless chip from /pci/u...@f,5 to /pci/usb, and spit out that error. That seems.. odd. Any insight into the reasoning for this mangling? _______________________________________________ devicetree-discuss mailing list [email protected] https://lists.ozlabs.org/listinfo/devicetree-discuss
