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| author | James Morris <jmorris@namei.org> | 2008-09-21 17:41:56 -0700 |
|---|---|---|
| committer | James Morris <jmorris@namei.org> | 2008-09-21 17:41:56 -0700 |
| commit | ab2b49518e743962f71b94246855c44ee9cf52cc (patch) | |
| tree | 26b260a350f0a0a0d19b558bf147b812e3a1564c /arch/x86/kernel/hpet.c | |
| parent | f058925b201357fba48d56cc9c1719ae274b2022 (diff) | |
| parent | 72d31053f62c4bc464c2783974926969614a8649 (diff) | |
| download | lwn-ab2b49518e743962f71b94246855c44ee9cf52cc.tar.gz lwn-ab2b49518e743962f71b94246855c44ee9cf52cc.zip | |
Merge branch 'master' into next
Conflicts:
MAINTAINERS
Thanks for breaking my tree :-)
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'arch/x86/kernel/hpet.c')
| -rw-r--r-- | arch/x86/kernel/hpet.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c index 59fd3b6b1303..73deaffadd03 100644 --- a/arch/x86/kernel/hpet.c +++ b/arch/x86/kernel/hpet.c @@ -210,8 +210,8 @@ static void hpet_legacy_clockevent_register(void) /* Calculate the min / max delta */ hpet_clockevent.max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, &hpet_clockevent); - hpet_clockevent.min_delta_ns = clockevent_delta2ns(0x30, - &hpet_clockevent); + /* 5 usec minimum reprogramming delta. */ + hpet_clockevent.min_delta_ns = 5000; /* * Start hpet with the boot cpu mask and make it @@ -270,15 +270,22 @@ static void hpet_legacy_set_mode(enum clock_event_mode mode, } static int hpet_legacy_next_event(unsigned long delta, - struct clock_event_device *evt) + struct clock_event_device *evt) { - unsigned long cnt; + u32 cnt; cnt = hpet_readl(HPET_COUNTER); - cnt += delta; + cnt += (u32) delta; hpet_writel(cnt, HPET_T0_CMP); - return ((long)(hpet_readl(HPET_COUNTER) - cnt ) > 0) ? -ETIME : 0; + /* + * We need to read back the CMP register to make sure that + * what we wrote hit the chip before we compare it to the + * counter. + */ + WARN_ON((u32)hpet_readl(HPET_T0_CMP) != cnt); + + return (s32)((u32)hpet_readl(HPET_COUNTER) - cnt) >= 0 ? -ETIME : 0; } /* |