[PATCH v4 00/15] multi-cluster power management

[Nicolas Pitre]

This is version 4 of the patch series required to safely power up
and down CPUs in a cluster as can be found in b.L systems.  If nothing
major is reported, I'll send a pull request to Russell for this set
very soon.

Also included are the needed patches to allow CPU hotplug on RTSM
configured as a big.LITTLE system.  I'll hopefully send a separate pull
request for them later if the remaining issue with the CCI code can be
sorted out in time.

Please refer to http://article.gmane.org/gmane.linux.ports.arm.kernel/208625
for the initial series and particularly the cover page blurb for this work.

Thanks to those who provided review comments.

Changes from v3:

- DT binding documentation for the DCSCB.
- Patch to probe DT for DCSCB presence folded into the patch that
  introduced it.
- Patch to select SMP ops at boot time now split in two patches.
- Use all 8 bits from the MPIDR affinity fields in mcpm_head.S.
- Replaced gic_raise_softirq() with arch_send_wakeup_ipi_mask().
- Clear CTRL.C bit rather than calling cpu_proc_fin() to keep the I-cache
  enabled.
- Added definitions in the CCI code to clean up some magic values.

Changes from v2:

- The bL_ prefix has been changed into mcpm_ and surroundings adjusted
  accordingly.
- Documentation moved up one level in Documentation/arm/.
- Clarifications in commit log for patch #1 about future work.
- The debug macro in mcpm_head.S now displays CPU and cluster numbers.
- Patch improving mcpm_cpu_die() folded into the original patch that
  created it.
- Return -EADDRNOTAVAIL on ioremap failure.
- The auxcr patch moved down in the series to better identify dependencies.

Changes from v1:

- Pulled in Rob Herring's auxcr accessor patch and converted this series
  to it.
- VMajor rework of various barriers (some DSBs demoted to DMBs, etc.)
- The sync_mem() macro is now split and enhanced to properly process the
  cache for writers and readers in the cluster critical region helpers.
- BL_NR_CLUSTERS and BL_CPUS_PER_CLUSTER renamed to BL_MAX_CLUSTERS
  and BL_MAX_CPUS_PER_CLUSTER.
- Removed unused C definitions and prototypes for vlocks.
- Simplified the vlock memory allocation.
- The vlock code is GPL v2.
- Replaced MPIDR inline asm by read_cpuid_mpidr().
- Use of MPIDR_AFFINITY_LEVEL() to replace explicit shifts and masks.
- Dropped gic_cpu_if_down().
- Added a DSB before SEV and WFI.
- Fixed power_up_setup helper prototype.
- Nuked smp_wmb() in bL_set_entry_vector().
- Moved the CCI driver to drivers/bus/.
- Dependency on CONFIG_EXPERIMENTAL removed.
- Leftover garbage in Makefile removed.
- Added/clarified various comments in the assembly code.
- Some documentation typos fixed.
- Copyright notices updated to 2013

Still not addressed yet in this series:

- The CCI device tree binding descriptions.

Diffstat:

 Documentation/arm/cluster-pm-race-avoidance.txt | 498 ++++++++++++++++++
 Documentation/arm/vlocks.txt                    | 211 ++++++++
 .../devicetree/bindings/arm/rtsm-dcscb.txt      |  19 +
 arch/arm/Kconfig                                |   8 +
 arch/arm/common/Makefile                        |   1 +
 arch/arm/common/mcpm_entry.c                    | 314 +++++++++++
 arch/arm/common/mcpm_head.S                     | 219 ++++++++
 arch/arm/common/mcpm_platsmp.c                  |  86 +++
 arch/arm/common/vlock.S                         | 108 ++++
 arch/arm/common/vlock.h                         |  29 +
 arch/arm/include/asm/cp15.h                     |  14 +
 arch/arm/include/asm/mach/arch.h                |   3 +
 arch/arm/include/asm/mcpm_entry.h               | 190 +++++++
 arch/arm/kernel/setup.c                         |   5 +-
 arch/arm/mach-vexpress/Kconfig                  |   9 +
 arch/arm/mach-vexpress/Makefile                 |   1 +
 arch/arm/mach-vexpress/core.h                   |   2 +
 arch/arm/mach-vexpress/dcscb.c                  | 249 +++++++++
 arch/arm/mach-vexpress/dcscb_setup.S            |  80 +++
 arch/arm/mach-vexpress/platsmp.c                |  12 +
 arch/arm/mach-vexpress/v2m.c                    |   2 +-
 drivers/bus/Kconfig                             |   5 +
 drivers/bus/Makefile                            |   2 +
 drivers/bus/arm-cci.c                           | 125 +++++
 drivers/cpuidle/cpuidle-calxeda.c               |  14 -
 include/linux/arm-cci.h                         |  30 ++
 26 files changed, 2220 insertions(+), 16 deletions(-)