changelog
---------
v2 - v3
        - Addressed comment from Thomas Gleixner
        - Timestamps are available a little later in boot but still much
          earlier than in mainline. This significantly simplified this
          work.
v1 - v2
        In patch "x86/tsc: tsc early":
        - added tsc_adjusted_early()
        - fixed 32-bit compile error use do_div()

Adding early boot time stamps support for x86 machines.
SPARC patches for early boot time stamps are already integrated into
mainline linux.

Sample output
-------------
Before:
https://hastebin.com/jadaqukubu.scala

After:
https://hastebin.com/nubipozacu.scala

As seen above, currently timestamps are available from around the time when
"Security Framework" is initialized. But, 26s already passed until we
reached to this point.

Pavel Tatashin (2):
  sched/clock: interface to allow timestamps early in boot
  x86/tsc: use tsc early

 arch/x86/include/asm/tsc.h  |  4 +++
 arch/x86/kernel/setup.c     | 10 ++++++--
 arch/x86/kernel/time.c      | 22 ++++++++++++++++
 arch/x86/kernel/tsc.c       | 47 ++++++++++++++++++++++++++++++++++
 include/linux/sched/clock.h |  4 +++
 kernel/sched/clock.c        | 61 ++++++++++++++++++++++++++++++++++++++++++++-
 6 files changed, 145 insertions(+), 3 deletions(-)

-- 
2.14.0

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