OpenFirmware devices and hotplug events

Nathan Lynch nathanl at
Thu Mar 18 06:38:24 EST 2004

Dave Hansen wrote:
> I see what the data are for, but not why they are exposed to userspace.

Well, everything that firmware places in the device tree is exposed, for
better or worse.

> Do applications make the decisions about which drc index to use, or is
> that all done inside the kernel?  If  each ibm,my-drc-index were
> suddenly removed today, what applications would break?

If not explicitly specified, the decision about which drc index to add
or remove is made by a userspace program which is invoked by the
machine's management console (the HMC).  So that would break.


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