It turns out that the logical CPU mapping is useful even when !CONFIG_SMP
for manipulation of devices like interrupt and power controllers when
running a UP kernel on a CPU other than 0. This can happen when kexecing
a UP image from an SMP kernel.

In the future, multi-cluster systems running AMP configurations will
require something similar for mapping cluster IDs, so it makes sense to
decouple this logic in preparation for this support.
Acked-by: NYang Bai <hamo.by@gmail.com>
Acked-by: NMarc Zyngier <marc.zyngier@arm.com>
Reported-by: NJoerg Roedel <joerg.roedel@amd.com>
Signed-off-by: NWill Deacon <will.deacon@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

This patch uses the new cpu_logical_map() macro for converting logical
CPU numbers into physical numbers when dealing with the pen_release
variable in the SMP boot and CPU hotplug paths.
Signed-off-by: NWill Deacon <will.deacon@arm.com>

Use the definition we've provided in asm/system.h rather than
numeric constants.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The original scheme for reporting spurious wakeups was broken - it
tried to use printk() from a context which wasn't coherent with the
other CPUs, which risks corrupting the printk() data.

Fix this by noting the number spurious wakeups, and only report them
when we are properly woken - when we will be coherent with the rest
of the system.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

platform_cpu_die() is entered from the CPU's own idle thread, which
can not be migrated to other CPUs.  Moreover, the 'cpu' argument
comes from the thread info, which will always be the 'current'
CPU.  So remove this useless bug check.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

We always need to wait for the dying CPU to reach a safe state before
taking it down, irrespective of the requirements of the platform.
Move the completion code into the ARM SMP hotplug code rather than
having each platform re-implement this.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

Consistently name all SMP platform related functions.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

The MCR for flushing the whole D cache is undefined on ARMv7 CPUs.
Signed-off-by: NHarry Fearnhamm <Harry.Fearnhamm@arm.com>
Signed-off-by: NCatalin Marinas <catalin.marinas@arm.com>

Add platform specific parts for hotplug CPU support for the
Realview board.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>