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Diffstat (limited to 'arch/x86/kernel/hpet.c')
-rw-r--r--arch/x86/kernel/hpet.c97
1 files changed, 78 insertions, 19 deletions
diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index cd759ad90690..648b3a2a3a44 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -80,6 +80,7 @@ static inline void hpet_clear_mapping(void)
*/
static int boot_hpet_disable;
int hpet_force_user;
+static int hpet_verbose;
static int __init hpet_setup(char *str)
{
@@ -88,6 +89,8 @@ static int __init hpet_setup(char *str)
boot_hpet_disable = 1;
if (!strncmp("force", str, 5))
hpet_force_user = 1;
+ if (!strncmp("verbose", str, 7))
+ hpet_verbose = 1;
}
return 1;
}
@@ -119,6 +122,43 @@ int is_hpet_enabled(void)
}
EXPORT_SYMBOL_GPL(is_hpet_enabled);
+static void _hpet_print_config(const char *function, int line)
+{
+ u32 i, timers, l, h;
+ printk(KERN_INFO "hpet: %s(%d):\n", function, line);
+ l = hpet_readl(HPET_ID);
+ h = hpet_readl(HPET_PERIOD);
+ timers = ((l & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1;
+ printk(KERN_INFO "hpet: ID: 0x%x, PERIOD: 0x%x\n", l, h);
+ l = hpet_readl(HPET_CFG);
+ h = hpet_readl(HPET_STATUS);
+ printk(KERN_INFO "hpet: CFG: 0x%x, STATUS: 0x%x\n", l, h);
+ l = hpet_readl(HPET_COUNTER);
+ h = hpet_readl(HPET_COUNTER+4);
+ printk(KERN_INFO "hpet: COUNTER_l: 0x%x, COUNTER_h: 0x%x\n", l, h);
+
+ for (i = 0; i < timers; i++) {
+ l = hpet_readl(HPET_Tn_CFG(i));
+ h = hpet_readl(HPET_Tn_CFG(i)+4);
+ printk(KERN_INFO "hpet: T%d: CFG_l: 0x%x, CFG_h: 0x%x\n",
+ i, l, h);
+ l = hpet_readl(HPET_Tn_CMP(i));
+ h = hpet_readl(HPET_Tn_CMP(i)+4);
+ printk(KERN_INFO "hpet: T%d: CMP_l: 0x%x, CMP_h: 0x%x\n",
+ i, l, h);
+ l = hpet_readl(HPET_Tn_ROUTE(i));
+ h = hpet_readl(HPET_Tn_ROUTE(i)+4);
+ printk(KERN_INFO "hpet: T%d ROUTE_l: 0x%x, ROUTE_h: 0x%x\n",
+ i, l, h);
+ }
+}
+
+#define hpet_print_config() \
+do { \
+ if (hpet_verbose) \
+ _hpet_print_config(__FUNCTION__, __LINE__); \
+} while (0)
+
/*
* When the hpet driver (/dev/hpet) is enabled, we need to reserve
* timer 0 and timer 1 in case of RTC emulation.
@@ -191,27 +231,37 @@ static struct clock_event_device hpet_clockevent = {
.rating = 50,
};
-static void hpet_start_counter(void)
+static void hpet_stop_counter(void)
{
unsigned long cfg = hpet_readl(HPET_CFG);
-
cfg &= ~HPET_CFG_ENABLE;
hpet_writel(cfg, HPET_CFG);
hpet_writel(0, HPET_COUNTER);
hpet_writel(0, HPET_COUNTER + 4);
+}
+
+static void hpet_start_counter(void)
+{
+ unsigned long cfg = hpet_readl(HPET_CFG);
cfg |= HPET_CFG_ENABLE;
hpet_writel(cfg, HPET_CFG);
}
+static void hpet_restart_counter(void)
+{
+ hpet_stop_counter();
+ hpet_start_counter();
+}
+
static void hpet_resume_device(void)
{
force_hpet_resume();
}
-static void hpet_restart_counter(void)
+static void hpet_resume_counter(void)
{
hpet_resume_device();
- hpet_start_counter();
+ hpet_restart_counter();
}
static void hpet_enable_legacy_int(void)
@@ -259,27 +309,23 @@ static int hpet_setup_msi_irq(unsigned int irq);
static void hpet_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt, int timer)
{
- unsigned long cfg, cmp, now;
+ unsigned long cfg;
uint64_t delta;
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
+ hpet_stop_counter();
delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * evt->mult;
delta >>= evt->shift;
- now = hpet_readl(HPET_COUNTER);
- cmp = now + (unsigned long) delta;
cfg = hpet_readl(HPET_Tn_CFG(timer));
+ /* Make sure we use edge triggered interrupts */
+ cfg &= ~HPET_TN_LEVEL;
cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC |
HPET_TN_SETVAL | HPET_TN_32BIT;
hpet_writel(cfg, HPET_Tn_CFG(timer));
- /*
- * The first write after writing TN_SETVAL to the
- * config register sets the counter value, the second
- * write sets the period.
- */
- hpet_writel(cmp, HPET_Tn_CMP(timer));
- udelay(1);
hpet_writel((unsigned long) delta, HPET_Tn_CMP(timer));
+ hpet_start_counter();
+ hpet_print_config();
break;
case CLOCK_EVT_MODE_ONESHOT:
@@ -306,6 +352,7 @@ static void hpet_set_mode(enum clock_event_mode mode,
irq_set_affinity(hdev->irq, cpumask_of(hdev->cpu));
enable_irq(hdev->irq);
}
+ hpet_print_config();
break;
}
}
@@ -524,6 +571,7 @@ static void hpet_msi_capability_lookup(unsigned int start_timer)
num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT);
num_timers++; /* Value read out starts from 0 */
+ hpet_print_config();
hpet_devs = kzalloc(sizeof(struct hpet_dev) * num_timers, GFP_KERNEL);
if (!hpet_devs)
@@ -628,11 +676,12 @@ static int hpet_cpuhp_notify(struct notifier_block *n,
switch (action & 0xf) {
case CPU_ONLINE:
- INIT_DELAYED_WORK(&work.work, hpet_work);
+ INIT_DELAYED_WORK_ON_STACK(&work.work, hpet_work);
init_completion(&work.complete);
/* FIXME: add schedule_work_on() */
schedule_delayed_work_on(cpu, &work.work, 0);
wait_for_completion(&work.complete);
+ destroy_timer_on_stack(&work.work.timer);
break;
case CPU_DEAD:
if (hdev) {
@@ -692,7 +741,7 @@ static struct clocksource clocksource_hpet = {
.mask = HPET_MASK,
.shift = HPET_SHIFT,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
- .resume = hpet_restart_counter,
+ .resume = hpet_resume_counter,
#ifdef CONFIG_X86_64
.vread = vread_hpet,
#endif
@@ -704,7 +753,7 @@ static int hpet_clocksource_register(void)
cycle_t t1;
/* Start the counter */
- hpet_start_counter();
+ hpet_restart_counter();
/* Verify whether hpet counter works */
t1 = read_hpet();
@@ -790,6 +839,7 @@ int __init hpet_enable(void)
* information and the number of channels
*/
id = hpet_readl(HPET_ID);
+ hpet_print_config();
#ifdef CONFIG_HPET_EMULATE_RTC
/*
@@ -842,6 +892,7 @@ static __init int hpet_late_init(void)
return -ENODEV;
hpet_reserve_platform_timers(hpet_readl(HPET_ID));
+ hpet_print_config();
for_each_online_cpu(cpu) {
hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu);
@@ -896,7 +947,7 @@ static unsigned long hpet_rtc_flags;
static int hpet_prev_update_sec;
static struct rtc_time hpet_alarm_time;
static unsigned long hpet_pie_count;
-static unsigned long hpet_t1_cmp;
+static u32 hpet_t1_cmp;
static unsigned long hpet_default_delta;
static unsigned long hpet_pie_delta;
static unsigned long hpet_pie_limit;
@@ -904,6 +955,14 @@ static unsigned long hpet_pie_limit;
static rtc_irq_handler irq_handler;
/*
+ * Check that the hpet counter c1 is ahead of the c2
+ */
+static inline int hpet_cnt_ahead(u32 c1, u32 c2)
+{
+ return (s32)(c2 - c1) < 0;
+}
+
+/*
* Registers a IRQ handler.
*/
int hpet_register_irq_handler(rtc_irq_handler handler)
@@ -1074,7 +1133,7 @@ static void hpet_rtc_timer_reinit(void)
hpet_t1_cmp += delta;
hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
lost_ints++;
- } while ((long)(hpet_readl(HPET_COUNTER) - hpet_t1_cmp) > 0);
+ } while (!hpet_cnt_ahead(hpet_t1_cmp, hpet_readl(HPET_COUNTER)));
if (lost_ints) {
if (hpet_rtc_flags & RTC_PIE)
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-28 12:09:48 +0000