[PATCH 0/3] powerpc: Free up CPU feature bits

Paul Mackerras paulus at ozlabs.org
Tue Mar 20 08:46:10 AEDT 2018

This patch series is against the powerpc next branch.  It takes
advantage of the fact that there are only a few CPU feature bits that
are meaningful on both 32-bit and 64-bit platforms.  At the moment,
many of the 64 bits of the CPU feature mask on 64-bit platforms are
taken up with bits which are only relevant to 32-bit platforms.  This
series rearranges things so that we can use those bits for new
features that are relevant only to 64-bit platforms.  With this, there
are now 20 bits available for new 64-bit features.

To make things simpler, we use the bottom 12 bits of the CPU feature
word for features that are relevant to both 32-bit and 64-bit
platforms.  The remaining 20 or 52 bits are then available for
features specific to 32-bit or 64-bit platforms.


 arch/powerpc/include/asm/cputable.h       | 223 +++++++++++++++---------------
 arch/powerpc/include/asm/time.h           |   2 +-
 arch/powerpc/kernel/cpu_setup_6xx.S       |   2 +-
 arch/powerpc/kernel/cpu_setup_fsl_booke.S |   2 +-
 arch/powerpc/kernel/dt_cpu_ftrs.c         |   3 +-
 arch/powerpc/kernel/vdso.c                |  12 +-
 6 files changed, 122 insertions(+), 122 deletions(-)

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