[PATCH 0/3] powernv:idle: Fixes for CPU-Hotplug on POWER DD1.0

From: Gautham R. Shenoy
Date: Mon Mar 13 2017 - 02:01:58 EST

From: "Gautham R. Shenoy" <ego@xxxxxxxxxxxxxxxxxx>


This patchset contains fixes to make CPU-Hotplug working on correctly
on POWER9 DD1 systems.

There are three patches in the series.

- The first patch adds a fallback mechanism for CPU-Hotplug when no
platform idle state is available.

- The second patch ensures that the kernel doesn't use any stop state
that is not exposed by the firmware.

- The third patch adds a recovery framework for correctly recovering
paca pointer of the thread waking up from a stop.

These patches are based on powerpc/linux.git "fixes" with the top
commit a7d2475af7aed ("powerpc: Sort the selects under CONFIG_PPC").

The patches have been tested with stop1 (ESL=EC=1) as the
deepest-state entered into during CPU-Hotplug.

Gautham R. Shenoy (3):
powernv:smp: Add busy-wait loop as fall back for CPU-Hotplug
powernv:idle: Don't override default/deepest directly in kernel
powernv:Recover correct PACA on wakeup from a stop on P9 DD1

arch/powerpc/include/asm/paca.h | 5 ++++
arch/powerpc/kernel/asm-offsets.c | 1 +
arch/powerpc/kernel/idle_book3s.S | 43 +++++++++++++++++++++++++++-
arch/powerpc/platforms/powernv/idle.c | 49 ++++++++++++++++++++++++++------
arch/powerpc/platforms/powernv/powernv.h | 1 +
arch/powerpc/platforms/powernv/smp.c | 18 ++++++++++--
6 files changed, 105 insertions(+), 12 deletions(-)