The automatic CPU power state machine for B15 CPUs does not work
reliably as-is. This patch implements a manual sequence in software to
replace it.
This was tested successfully with over 10,000 hotplug cycles of
something like this:
echo 0 > /sys/devices/system/cpu/cpu1/online
echo 1 > /sys/devices/system/cpu/cpu1/online
whereas the existing sequence often locks up after a few hundred cycles.
Fixes: 62639c2f53 ("ARM: brcmstb: reintroduce SMP support")
Acked-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
a1ad3b94a7