On Tue, 2016-03-15 at 21:10 +1000, Dave Airlie wrote:
I guess that's only useful until we get runtime PM support.
For the discrete GPUs on regular laptops we have runtime PM support for powerdown already. Some newer laptops need a bit of work in the PCIE layer but for most things we have it covered. The known broken ones are Apple laptops. If the apple-gmux code is working well enough to power off GPUs, then it should be possible to hook up runtime-pm on those machines pretty simply.
So there shouldn't really be a case we care about.
runtime PM for the Intel GPU isn't as important. We don't even want to turn the i915 fully off anymore.
Fair enough. And it's not that big a problem if we want to try and run the compositor on the integrated card by default either.