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Merge commit 'v2.6.27-rc6' into timers/hpet

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This commit is contained in:
Ingo Molnar
2008-09-14 18:24:00 +02:00
parent e7250b8ae3 adee14b2e1
commit 83bd6998b0
5976 changed files with 156862 additions and 62241 deletions
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43
arch/x86/kernel/hpet.c
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@@ -214,8 +214,8 @@ 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
@@ -274,15 +274,22 @@ 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;
}
/*
@@ -363,6 +370,7 @@ static int hpet_clocksource_register(void)
int __init hpet_enable(void)
{
unsigned long id;
int i;
if (!is_hpet_capable())
return 0;
@@ -373,6 +381,29 @@ int __init hpet_enable(void)
* Read the period and check for a sane value:
*/
hpet_period = hpet_readl(HPET_PERIOD);
/*
* AMD SB700 based systems with spread spectrum enabled use a
* SMM based HPET emulation to provide proper frequency
* setting. The SMM code is initialized with the first HPET
* register access and takes some time to complete. During
* this time the config register reads 0xffffffff. We check
* for max. 1000 loops whether the config register reads a non
* 0xffffffff value to make sure that HPET is up and running
* before we go further. A counting loop is safe, as the HPET
* access takes thousands of CPU cycles. On non SB700 based
* machines this check is only done once and has no side
* effects.
*/
for (i = 0; hpet_readl(HPET_CFG) == 0xFFFFFFFF; i++) {
if (i == 1000) {
printk(KERN_WARNING
"HPET config register value = 0xFFFFFFFF. "
"Disabling HPET\n");
goto out_nohpet;
}
}
if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD)
goto out_nohpet;