[PATCH v2 0/3] powernv/cpuidle: Fastsleep workaround and fixes

Shreyas B. Prabhu shreyas at linux.vnet.ibm.com
Wed Oct 1 17:45:57 EST 2014

Fast sleep is an idle state, where the core and the L1 and L2
caches are brought down to a threshold voltage. This also means that
the communication between L2 and L3 caches have to be fenced. However
the current P8 chips have a bug wherein this fencing between L2 and
L3 caches get delayed by a cpu cycle. This can delay L3 response to
the other cpus if they request for data during this time. Thus they
would fetch the same data from the memory which could lead to data
corruption if L3 cache is not flushed. 

This series overcomes above problem in kernel.

Cc: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Cc: Paul Mackerras <paulus at samba.org>
Cc: Michael Ellerman <mpe at ellerman.id.au>
Cc: Rafael J. Wysocki <rjw at rjwysocki.net>
Cc: linux-pm at vger.kernel.org
Cc: linuxppc-dev at lists.ozlabs.org
Cc: Srivatsa S. Bhat <srivatsa at mit.edu>
Cc: Preeti U. Murthy <preeti at linux.vnet.ibm.com>
Cc: Vaidyanathan Srinivasan <svaidy at linux.vnet.ibm.com>

Rebased on 3.17-rc7
Split from 'powerpc/powernv: Support for fastsleep and winkle'


Preeti U Murthy (1):
  powerpc/powernv/cpuidle: Add workaround to enable fastsleep

Shreyas B. Prabhu (1):
  powerpc/kvm/book3s_hv: Enable CPUs to run guest after waking up from

Srivatsa S. Bhat (1):
  powerpc/powernv: Enable Offline CPUs to enter deep idle states

 arch/powerpc/include/asm/machdep.h             |   3 +
 arch/powerpc/include/asm/opal.h                |   7 ++
 arch/powerpc/include/asm/processor.h           |   4 +-
 arch/powerpc/kernel/exceptions-64s.S           |  35 ++++----
 arch/powerpc/kernel/idle.c                     |  19 ++++
 arch/powerpc/kernel/idle_power7.S              |   2 +-
 arch/powerpc/platforms/powernv/opal-wrappers.S |   1 +
 arch/powerpc/platforms/powernv/powernv.h       |   7 ++
 arch/powerpc/platforms/powernv/setup.c         | 118 +++++++++++++++++++++++++
 arch/powerpc/platforms/powernv/smp.c           |  11 ++-
 drivers/cpuidle/cpuidle-powernv.c              |  13 ++-
 11 files changed, 194 insertions(+), 26 deletions(-)


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