/*
* Some boards have the PMTMR running way too fast. We check
* the PMTMR rate against PIT channel 2 to catch these cases.
*/
static int verify_pmtmr_rate(void)
{
cycle_t value1, value2;
unsigned long count, delta;
mach_prepare_counter();
value1 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
mach_countup(&count);
value2 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
delta = (value2 - value1) & ACPI_PM_MASK;
/* Check that the PMTMR delta is within 5% of what we expect */
if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
#ifdef CONFIG_DEBUG_PRINTK
printk(KERN_INFO "PM-Timer running at invalid rate: %lu%% "
"of normal - aborting.\n",
100UL * delta / PMTMR_EXPECTED_RATE);
#else
;
#endif
return -1;
}
return 0;
}
unsigned long native_calculate_cpu_khz(void)
{
unsigned long long start, end;
unsigned long count;
u64 delta64;
int i;
unsigned long flags;
local_irq_save(flags);
/* run 3 times to ensure the cache is warm */
for (i = 0; i < 3; i++) {
mach_prepare_counter();
rdtscll(start);
mach_countup(&count);
rdtscll(end);
}
/*
* Error: ECTCNEVERSET
* The CTC wasn't reliable: we got a hit on the very first read,
* or the CPU was so fast/slow that the quotient wouldn't fit in
* 32 bits..
*/
if (count <= 1)
goto err;
delta64 = end - start;
/* cpu freq too fast: */
if (delta64 > (1ULL<<32))
goto err;
/* cpu freq too slow: */
if (delta64 <= CALIBRATE_TIME_MSEC)
goto err;
delta64 += CALIBRATE_TIME_MSEC/2; /* round for do_div */
do_div(delta64,CALIBRATE_TIME_MSEC);
local_irq_restore(flags);
return (unsigned long)delta64;
err:
local_irq_restore(flags);
return 0;
}
/*
* Some boards have the PMTMR running way too fast. We check
* the PMTMR rate against PIT channel 2 to catch these cases.
*/
static int verify_pmtmr_rate(void)
{
u32 value1, value2;
unsigned long count, delta;
mach_prepare_counter();
value1 = read_pmtmr();
mach_countup(&count);
value2 = read_pmtmr();
delta = (value2 - value1) & ACPI_PM_MASK;
/* Check that the PMTMR delta is within 5% of what we expect */
if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
printk(KERN_INFO "PM-Timer running at invalid rate: %lu%% of normal - aborting.\n", 100UL * delta / PMTMR_EXPECTED_RATE);
return -1;
}
return 0;
}
static int verify_pmtmr_rate(void)
{
cycle_t value1, value2;
unsigned long count, delta;
mach_prepare_counter();
value1 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
mach_countup(&count);
value2 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
delta = (value2 - value1) & ACPI_PM_MASK;
if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
printk(KERN_INFO "PM-Timer running at invalid rate: %lu%% "
"of normal - aborting.\n",
100UL * delta / PMTMR_EXPECTED_RATE);
return -1;
}
return 0;
}
