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Diffstat (limited to 'arch/i386/kernel/hpet.c')
-rw-r--r--arch/i386/kernel/hpet.c98
1 files changed, 30 insertions, 68 deletions
diff --git a/arch/i386/kernel/hpet.c b/arch/i386/kernel/hpet.c
index 17d73459fc5..533d4932bc7 100644
--- a/arch/i386/kernel/hpet.c
+++ b/arch/i386/kernel/hpet.c
@@ -5,6 +5,7 @@
#include <linux/init.h>
#include <linux/sysdev.h>
#include <linux/pm.h>
+#include <linux/delay.h>
#include <asm/hpet.h>
#include <asm/io.h>
@@ -187,6 +188,10 @@ static void hpet_set_mode(enum clock_event_mode mode,
cfg &= ~HPET_TN_ENABLE;
hpet_writel(cfg, HPET_T0_CFG);
break;
+
+ case CLOCK_EVT_MODE_RESUME:
+ hpet_enable_int();
+ break;
}
}
@@ -217,6 +222,7 @@ static struct clocksource clocksource_hpet = {
.mask = HPET_MASK,
.shift = HPET_SHIFT,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+ .resume = hpet_start_counter,
};
/*
@@ -226,7 +232,8 @@ int __init hpet_enable(void)
{
unsigned long id;
uint64_t hpet_freq;
- u64 tmp;
+ u64 tmp, start, now;
+ cycle_t t1;
if (!is_hpet_capable())
return 0;
@@ -273,6 +280,27 @@ int __init hpet_enable(void)
/* Start the counter */
hpet_start_counter();
+ /* Verify whether hpet counter works */
+ t1 = read_hpet();
+ rdtscll(start);
+
+ /*
+ * We don't know the TSC frequency yet, but waiting for
+ * 200000 TSC cycles is safe:
+ * 4 GHz == 50us
+ * 1 GHz == 200us
+ */
+ do {
+ rep_nop();
+ rdtscll(now);
+ } while ((now - start) < 200000UL);
+
+ if (t1 == read_hpet()) {
+ printk(KERN_WARNING
+ "HPET counter not counting. HPET disabled\n");
+ goto out_nohpet;
+ }
+
/* Initialize and register HPET clocksource
*
* hpet period is in femto seconds per cycle
@@ -291,7 +319,6 @@ int __init hpet_enable(void)
clocksource_register(&clocksource_hpet);
-
if (id & HPET_ID_LEGSUP) {
hpet_enable_int();
hpet_reserve_platform_timers(id);
@@ -299,7 +326,7 @@ int __init hpet_enable(void)
* Start hpet with the boot cpu mask and make it
* global after the IO_APIC has been initialized.
*/
- hpet_clockevent.cpumask =cpumask_of_cpu(0);
+ hpet_clockevent.cpumask = cpumask_of_cpu(smp_processor_id());
clockevents_register_device(&hpet_clockevent);
global_clock_event = &hpet_clockevent;
return 1;
@@ -524,68 +551,3 @@ irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
#endif
-
-
-/*
- * Suspend/resume part
- */
-
-#ifdef CONFIG_PM
-
-static int hpet_suspend(struct sys_device *sys_device, pm_message_t state)
-{
- unsigned long cfg = hpet_readl(HPET_CFG);
-
- cfg &= ~(HPET_CFG_ENABLE|HPET_CFG_LEGACY);
- hpet_writel(cfg, HPET_CFG);
-
- return 0;
-}
-
-static int hpet_resume(struct sys_device *sys_device)
-{
- unsigned int id;
-
- hpet_start_counter();
-
- id = hpet_readl(HPET_ID);
-
- if (id & HPET_ID_LEGSUP)
- hpet_enable_int();
-
- return 0;
-}
-
-static struct sysdev_class hpet_class = {
- set_kset_name("hpet"),
- .suspend = hpet_suspend,
- .resume = hpet_resume,
-};
-
-static struct sys_device hpet_device = {
- .id = 0,
- .cls = &hpet_class,
-};
-
-
-static __init int hpet_register_sysfs(void)
-{
- int err;
-
- if (!is_hpet_capable())
- return 0;
-
- err = sysdev_class_register(&hpet_class);
-
- if (!err) {
- err = sysdev_register(&hpet_device);
- if (err)
- sysdev_class_unregister(&hpet_class);
- }
-
- return err;
-}
-
-device_initcall(hpet_register_sysfs);
-
-#endif