#include <linux/init.h>
#include <linux/sysdev.h>
#include <linux/pm.h>
-#include <linux/delay.h>
#include <asm/fixmap.h>
#include <asm/hpet.h>
/* FSEC = 10^-15
NSEC = 10^-9 */
-#define FSEC_PER_NSEC 1000000
+#define FSEC_PER_NSEC 1000000L
/*
* HPET address is set in acpi/boot.c, when an ACPI entry exists
}
#ifdef CONFIG_X86_64
-
#include <asm/pgtable.h>
-
-static inline void hpet_set_mapping(void)
-{
- set_fixmap_nocache(FIX_HPET_BASE, hpet_address);
- __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);
- hpet_virt_address = (void __iomem *)fix_to_virt(FIX_HPET_BASE);
-}
-
-static inline void hpet_clear_mapping(void)
-{
- hpet_virt_address = NULL;
-}
-
-#else
+#endif
static inline void hpet_set_mapping(void)
{
hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
+#ifdef CONFIG_X86_64
+ __set_fixmap(VSYSCALL_HPET, hpet_address, PAGE_KERNEL_VSYSCALL_NOCACHE);
+#endif
}
static inline void hpet_clear_mapping(void)
iounmap(hpet_virt_address);
hpet_virt_address = NULL;
}
-#endif
/*
* HPET command line enable / disable
{
return is_hpet_capable() && hpet_legacy_int_enabled;
}
+EXPORT_SYMBOL_GPL(is_hpet_enabled);
/*
* When the hpet driver (/dev/hpet) is enabled, we need to reserve
static void hpet_reserve_platform_timers(unsigned long id)
{
struct hpet __iomem *hpet = hpet_virt_address;
- unsigned int nrtimers;
+ struct hpet_timer __iomem *timer = &hpet->hpet_timers[2];
+ unsigned int nrtimers, i;
struct hpet_data hd;
nrtimers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT) + 1;
#ifdef CONFIG_HPET_EMULATE_RTC
hpet_reserve_timer(&hd, 1);
#endif
+
hd.hd_irq[0] = HPET_LEGACY_8254;
hd.hd_irq[1] = HPET_LEGACY_RTC;
- /*
- * IRQs for the other timers are assigned dynamically
- * in hpet_alloc
- */
+ for (i = 2; i < nrtimers; timer++, i++) {
+ hd.hd_irq[i] = (readl(&timer->hpet_config) & Tn_INT_ROUTE_CNF_MASK) >>
+ Tn_INT_ROUTE_CNF_SHIFT;
+ }
+
hpet_alloc(&hd);
+
}
#else
static void hpet_reserve_platform_timers(unsigned long id) { }
static void hpet_legacy_clockevent_register(void)
{
- uint64_t hpet_freq;
-
/* Start HPET legacy interrupts */
hpet_enable_legacy_int();
/*
- * The period is a femto seconds value. We need to calculate the
- * scaled math multiplication factor for nanosecond to hpet tick
- * conversion.
+ * The mult factor is defined as (include/linux/clockchips.h)
+ * mult/2^shift = cyc/ns (in contrast to ns/cyc in clocksource.h)
+ * hpet_period is in units of femtoseconds (per cycle), so
+ * mult/2^shift = cyc/ns = 10^6/hpet_period
+ * mult = (10^6 * 2^shift)/hpet_period
+ * mult = (FSEC_PER_NSEC << hpet_clockevent.shift)/hpet_period
*/
- hpet_freq = 1000000000000000ULL;
- do_div(hpet_freq, hpet_period);
- hpet_clockevent.mult = div_sc((unsigned long) hpet_freq,
- NSEC_PER_SEC, 32);
+ hpet_clockevent.mult = div_sc((unsigned long) FSEC_PER_NSEC,
+ hpet_period, hpet_clockevent.shift);
/* 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
}
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;
}
/*
static int hpet_clocksource_register(void)
{
- u64 tmp, start, now;
+ u64 start, now;
cycle_t t1;
/* Start the counter */
return -ENODEV;
}
- /* Initialize and register HPET clocksource
- *
- * hpet period is in femto seconds per cycle
- * so we need to convert this to ns/cyc units
- * approximated by mult/2^shift
- *
- * fsec/cyc * 1nsec/1000000fsec = nsec/cyc = mult/2^shift
- * fsec/cyc * 1ns/1000000fsec * 2^shift = mult
- * fsec/cyc * 2^shift * 1nsec/1000000fsec = mult
- * (fsec/cyc << shift)/1000000 = mult
- * (hpet_period << shift)/FSEC_PER_NSEC = mult
+ /*
+ * The definition of mult is (include/linux/clocksource.h)
+ * mult/2^shift = ns/cyc and hpet_period is in units of fsec/cyc
+ * so we first need to convert hpet_period to ns/cyc units:
+ * mult/2^shift = ns/cyc = hpet_period/10^6
+ * mult = (hpet_period * 2^shift)/10^6
+ * mult = (hpet_period << shift)/FSEC_PER_NSEC
*/
- tmp = (u64)hpet_period << HPET_SHIFT;
- do_div(tmp, FSEC_PER_NSEC);
- clocksource_hpet.mult = (u32)tmp;
+ clocksource_hpet.mult = div_sc(hpet_period, FSEC_PER_NSEC, HPET_SHIFT);
clocksource_register(&clocksource_hpet);
return 0;
}
-/*
- * Try to setup the HPET timer
+/**
+ * hpet_enable - Try to setup the HPET timer. Returns 1 on success.
*/
int __init hpet_enable(void)
{
unsigned long id;
+ int i;
if (!is_hpet_capable())
return 0;
* 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;
*/
#include <linux/mc146818rtc.h>
#include <linux/rtc.h>
+#include <asm/rtc.h>
#define DEFAULT_RTC_INT_FREQ 64
#define DEFAULT_RTC_SHIFT 6
#define RTC_NUM_INTS 1
static unsigned long hpet_rtc_flags;
-static unsigned long hpet_prev_update_sec;
+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 unsigned long hpet_pie_delta;
static unsigned long hpet_pie_limit;
+static rtc_irq_handler irq_handler;
+
+/*
+ * Registers a IRQ handler.
+ */
+int hpet_register_irq_handler(rtc_irq_handler handler)
+{
+ if (!is_hpet_enabled())
+ return -ENODEV;
+ if (irq_handler)
+ return -EBUSY;
+
+ irq_handler = handler;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(hpet_register_irq_handler);
+
+/*
+ * Deregisters the IRQ handler registered with hpet_register_irq_handler()
+ * and does cleanup.
+ */
+void hpet_unregister_irq_handler(rtc_irq_handler handler)
+{
+ if (!is_hpet_enabled())
+ return;
+
+ irq_handler = NULL;
+ hpet_rtc_flags = 0;
+}
+EXPORT_SYMBOL_GPL(hpet_unregister_irq_handler);
+
/*
* Timer 1 for RTC emulation. We use one shot mode, as periodic mode
* is not supported by all HPET implementations for timer 1.
return 1;
}
+EXPORT_SYMBOL_GPL(hpet_rtc_timer_init);
/*
* The functions below are called from rtc driver.
hpet_rtc_flags &= ~bit_mask;
return 1;
}
+EXPORT_SYMBOL_GPL(hpet_mask_rtc_irq_bit);
int hpet_set_rtc_irq_bit(unsigned long bit_mask)
{
hpet_rtc_flags |= bit_mask;
+ if ((bit_mask & RTC_UIE) && !(oldbits & RTC_UIE))
+ hpet_prev_update_sec = -1;
+
if (!oldbits)
hpet_rtc_timer_init();
return 1;
}
+EXPORT_SYMBOL_GPL(hpet_set_rtc_irq_bit);
int hpet_set_alarm_time(unsigned char hrs, unsigned char min,
unsigned char sec)
return 1;
}
+EXPORT_SYMBOL_GPL(hpet_set_alarm_time);
int hpet_set_periodic_freq(unsigned long freq)
{
}
return 1;
}
+EXPORT_SYMBOL_GPL(hpet_set_periodic_freq);
int hpet_rtc_dropped_irq(void)
{
return is_hpet_enabled();
}
+EXPORT_SYMBOL_GPL(hpet_rtc_dropped_irq);
static void hpet_rtc_timer_reinit(void)
{
if (hpet_rtc_flags & RTC_PIE)
hpet_pie_count += lost_ints;
if (printk_ratelimit())
- printk(KERN_WARNING "rtc: lost %d interrupts\n",
+ printk(KERN_WARNING "hpet1: lost %d rtc interrupts\n",
lost_ints);
}
}
unsigned long rtc_int_flag = 0;
hpet_rtc_timer_reinit();
+ memset(&curr_time, 0, sizeof(struct rtc_time));
if (hpet_rtc_flags & (RTC_UIE | RTC_AIE))
- rtc_get_rtc_time(&curr_time);
+ get_rtc_time(&curr_time);
if (hpet_rtc_flags & RTC_UIE &&
curr_time.tm_sec != hpet_prev_update_sec) {
- rtc_int_flag = RTC_UF;
+ if (hpet_prev_update_sec >= 0)
+ rtc_int_flag = RTC_UF;
hpet_prev_update_sec = curr_time.tm_sec;
}
if (rtc_int_flag) {
rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8));
- rtc_interrupt(rtc_int_flag, dev_id);
+ if (irq_handler)
+ irq_handler(rtc_int_flag, dev_id);
}
return IRQ_HANDLED;
}
+EXPORT_SYMBOL_GPL(hpet_rtc_interrupt);
#endif
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff