The Power Management Unit on PowerMacs is very sensitive to timeouts during
async message exchanges. It uses rather crude protocol based on a shift
register with an interrupt and is almost continuously exchanging messages with
the host CPU on laptops.
This patch adds a routine to the open_pic driver to be able to select a PMU
driver so that it bumps it's interrupt priority to above the normal level.
This will allow PMU interrupts to occur while another interrupt is pending,
and thus reduce the risk of machine beeing abruptly shutdown by the PMU due to
a timeout in PMU communication caused by excessive interrupt latency. The
problem is very rare, and usually just doesn't happen, but it is still useful
to make things even more robust.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch updates the PowerMac cpufreq driver. It depends on the addition
of the suspend() method (my previous patch) and on the new flag I defined
to silence some warnings that are normal for us.
It fixes various issues related to cpufreq on pmac, including some crashes
on some models when sleeping the machine while in low speed, proper voltage
control on some newer machines, and adds voltage control on 750FX based G3
laptops.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Benjamin Herrenschmidt