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[0/2] improve ability to pass SPR defaults to Linux

Message ID 20171024114100.13714-1-npiggin@gmail.com
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Series improve ability to pass SPR defaults to Linux | expand

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Nicholas Piggin Oct. 24, 2017, 11:40 a.m. UTC 
I htink we need to go in this direction to avoid putting knowledge
of implementation specific SPRs and defaults in Linux. This helps
compatibility of new hardware on older software, and also firmware
updates can adjust default SPR settings if necessary.

DSCR on POWER9 has motivated these patches, but there are other
reasons for it too. Also other registers (e.g., Linux may want to
adjust TSCR).

There is a corresponding Linux kernel patch I'll send to
linuxppc-dev.

Thanks,
Nick

Nicholas Piggin (2):
  asm/head: initialize preferred DSCR value
  cpu: Unconditionally re-initialise SPRs in opal_reinit_cpus()

 asm/head.S          | 22 +++++++++++++++++++---
 core/cpu.c          |  7 +++++++
 include/processor.h |  1 +
 3 files changed, 27 insertions(+), 3 deletions(-)