[patch] axe RF_TIMESHARE?

[Warner Losh]

On Jul 9, 2014, at 4:08 AM, Bruce Evans <brde at optusnet.com.au> wrote:
> RF_TIMESHARE doesn't simplify this significantly.  Ownership of the
> interrupt should be claimed somewhere so that the interrupt resource
> is available at first open time.  That can probably be done using
> a super-device or some hack to own the interrupt by the first device
> that can share it.  Then you don't need a flag for it.  It seems too
> hard (bloated) to generalize RF_TIMESHARE so that all of the OUT2
> complications can be handled at the new-bus level.

I think that, while interesting, none of this has a bearing on RF_TIMESHARE.

For shared interrupts, we’ve used RF_SHARED for a long time. I don’t think anybody ever actually implemented RF_TIMESHARE apart from an aborted attempt by the ppcbus code which later wound up abandoning that effort (I think before it even made it into the tree).

It was an interesting concept, but we never used it and I think we can light a bonfire under it. There are other ways to share resources that have been used instead...

Warner

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