Commits
Gregory CLEMENT committed 626d686487b
ARM: mvebu: Implement the CPU hotplug support for the Armada 38x SoCs
This commit implements the CPU hotplug support for the Marvell Armada
38x platform. Similarly to what was done for the Armada XP, this
commit:
* Implements the ->cpu_die() function of SMP operations by calling
armada_38x_do_cpu_suspend() to enter the deep idle state for
CPUs going offline.
* Implements a dummy ->cpu_kill() function, simply needed for the
kernel to know we have CPU hotplug support.
* The mvebu_cortex_a9_boot_secondary() function makes sure to wake up
the CPU if waiting in deep idle state by sending an IPI before
deasserting the CPUs from reset. This is because
mvebu_cortex_a9_boot_secondary() is now used in two different
situations: for the initial boot of secondary CPUs (where CPU reset
deassert is used to wake up CPUs) and for CPU hotplug (where an IPI
is used to take CPU out of deep idle).
* At boot time, we exit from the idle state in the
->smp_secondary_init() hook.
This commit has been tested using CPU hotplug through sysfs
(/sys/devices/system/cpu/cpuX/online) and using kexec.
Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Link: https://lkml.kernel.org/r/1414669184-16785-5-git-send-email-gregory.clement@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>