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[POWERPC] pasemi: SMP timebase sync

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Timebase update is simple on PA6T, since global updates can be done from
one core by writing to an SPR.

Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Olof Johansson
2007-02-04 16:36:53 -06:00
committed by Paul Mackerras
parent f620be99e9
commit c388cfebbf
2 changed files with 31 additions and 2 deletions
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27
arch/powerpc/platforms/pasemi/setup.c
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@ -48,13 +48,36 @@ static void pas_restart(char *cmd)
}
#ifdef CONFIG_SMP
static DEFINE_SPINLOCK(timebase_lock);
static void __devinit pas_give_timebase(void)
{
unsigned long tb;
spin_lock(&timebase_lock);
mtspr(SPRN_TBCTL, TBCTL_FREEZE);
tb = mftb();
mtspr(SPRN_TBCTL, TBCTL_UPDATE_LOWER | (tb & 0xffffffff));
mtspr(SPRN_TBCTL, TBCTL_UPDATE_UPPER | (tb >> 32));
mtspr(SPRN_TBCTL, TBCTL_RESTART);
spin_unlock(&timebase_lock);
pr_debug("pas_give_timebase: cpu %d gave tb %lx\n",
smp_processor_id(), tb);
}
static void __devinit pas_take_timebase(void)
{
pr_debug("pas_take_timebase: cpu %d has tb %lx\n",
smp_processor_id(), mftb());
}
struct smp_ops_t pas_smp_ops = {
.probe = smp_mpic_probe,
.message_pass = smp_mpic_message_pass,
.kick_cpu = smp_generic_kick_cpu,
.setup_cpu = smp_mpic_setup_cpu,
.give_timebase = smp_generic_give_timebase,
.take_timebase = smp_generic_take_timebase,
.give_timebase = pas_give_timebase,
.take_timebase = pas_take_timebase,
};
#endif /* CONFIG_SMP */