On 03/11/15 16:27, Gabriel L. Somlo wrote: > Hi, > > I'm looking for the closest thing to an official spec for qemu's > fw_cfg device, and so far I have found this: > > http://lists.gnu.org/archive/html/qemu-devel/2011-04/msg00238.html > > but it apparently never got committed to qemu (any idea why not?).
Must have fallen through the cracks. (Just speculating; in April 2011 I had been with RH for less than half a year, and learning Xen. :)) > Googling around didn't get me much further than that. > > Is there anything better or more up to date floating around out > there somewhere ? I won't say "better", but it is "committed": check "Documentation/devicetree/bindings/arm/fw-cfg.txt" in the kernel tree. It is intentionally vague on the set of keys and fw_cfg files that qemu provides, because that's a moving target. You can only rely on the qemu source for those. Also, I updated Gleb's email address in the CC: header. If you have a ton of time, you could try documenting fw_cfg yourself, but as I said, it's a moving target, so the description would either become stale quickly, or require people to keep it in sync with the source all the time. Updating documentation sucks *hard*. (At one point I had also started a text file like Jordan's, but I didn't even get as far as posting it anywhere; I just gave up.) Thanks Laszlo
