x86: hpet: stop HPET_COUNTER when programming periodic mode
commit
c23e253e67c9d8a91a0ffa33c1f571a17f0a2403 upstream
x86: hpet: stop HPET_COUNTER when programming periodic mode
Impact: fix system hang on some systems operating with HZ_1000
On a system that stalled with HZ_1000, the first value written to
T0_CMP (when the main counter was not stopped) did not trigger an
interrupt. Instead after the main counter wrapped around (after
several minutes) an interrupt was triggered and afterwards the
periodic interrupt took effect.
This can be fixed by implementing HPET spec recommendation for
programming the periodic mode (i.e. stopping the main counter).
[cebbert@redhat.com: backport to 2.6.29]
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Mark Hounschell <markh@compro.net>
Cc: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: Chuck Ebbert <cebbert@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>