bool
default y
+config GENERIC_CLOCKEVENTS
+ bool
+ default y
+
+config GENERIC_CLOCKEVENTS_BROADCAST
+ bool
+ default y
+
config LOCKDEP_SUPPORT
bool
default y
obj-$(CONFIG_MODULES) += module.o
obj-y += sysenter.o vsyscall.o
obj-$(CONFIG_ACPI_SRAT) += srat.o
-obj-$(CONFIG_HPET_TIMER) += time_hpet.o
obj-$(CONFIG_EFI) += efi.o efi_stub.o
obj-$(CONFIG_DOUBLEFAULT) += doublefault.o
obj-$(CONFIG_VM86) += vm86.o
#include <linux/kernel_stat.h>
#include <linux/sysdev.h>
#include <linux/cpu.h>
+#include <linux/clockchips.h>
#include <linux/module.h>
#include <asm/atomic.h>
# error SPURIOUS_APIC_VECTOR definition error
#endif
-/*
- * cpu_mask that denotes the CPUs that needs timer interrupt coming in as
- * IPIs in place of local APIC timers
- */
-static cpumask_t timer_bcast_ipi;
-
/*
* Knob to control our willingness to enable the local APIC.
*
*/
static int enable_local_apic __initdata = 0;
+/* Enable local APIC timer for highres/dyntick on UP */
+static int enable_local_apic_timer __initdata = 0;
+
/*
* Debug level, exported for io_apic.c
*/
int apic_verbosity;
-static void apic_pm_activate(void);
+static unsigned int calibration_result;
+static int lapic_next_event(unsigned long delta,
+ struct clock_event_device *evt);
+static void lapic_timer_setup(enum clock_event_mode mode,
+ struct clock_event_device *evt);
+static void lapic_timer_broadcast(cpumask_t mask);
+static void apic_pm_activate(void);
-/* Using APIC to generate smp_local_timer_interrupt? */
-int using_apic_timer __read_mostly = 0;
+/*
+ * The local apic timer can be used for any function which is CPU local.
+ */
+static struct clock_event_device lapic_clockevent = {
+ .name = "lapic",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
+ | CLOCK_EVT_FEAT_C3STOP,
+ .shift = 32,
+ .set_mode = lapic_timer_setup,
+ .set_next_event = lapic_next_event,
+ .broadcast = lapic_timer_broadcast,
+ .rating = 100,
+ .irq = -1,
+};
+static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
/* Local APIC was disabled by the BIOS and enabled by the kernel */
static int enabled_via_apicbase;
* closely follows bus clocks.
*/
+/*
+ * FIXME: Move this to i8253.h. There is no need to keep the access to
+ * the PIT scattered all around the place -tglx
+ */
+
/*
* The timer chip is already set up at HZ interrupts per second here,
* but we do not accept timer interrupts yet. We only allow the BP
#define APIC_DIVISOR 16
-static void __setup_APIC_LVTT(unsigned int clocks)
+static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
{
unsigned int lvtt_value, tmp_value;
- int cpu = smp_processor_id();
- lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
+ lvtt_value = LOCAL_TIMER_VECTOR;
+ if (!oneshot)
+ lvtt_value |= APIC_LVT_TIMER_PERIODIC;
if (!lapic_is_integrated())
lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
- if (cpu_isset(cpu, timer_bcast_ipi))
+ if (!irqen)
lvtt_value |= APIC_LVT_MASKED;
apic_write_around(APIC_LVTT, lvtt_value);
& ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
| APIC_TDR_DIV_16);
- apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
+ if (!oneshot)
+ apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
+}
+
+/*
+ * Program the next event, relative to now
+ */
+static int lapic_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ apic_write_around(APIC_TMICT, delta);
+ return 0;
}
-static void __devinit setup_APIC_timer(unsigned int clocks)
+/*
+ * Setup the lapic timer in periodic or oneshot mode
+ */
+static void lapic_timer_setup(enum clock_event_mode mode,
+ struct clock_event_device *evt)
{
unsigned long flags;
+ unsigned int v;
local_irq_save(flags);
- /*
- * Wait for IRQ0's slice:
- */
- wait_timer_tick();
-
- __setup_APIC_LVTT(clocks);
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ case CLOCK_EVT_MODE_ONESHOT:
+ __setup_APIC_LVTT(calibration_result,
+ mode != CLOCK_EVT_MODE_PERIODIC, 1);
+ break;
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ v = apic_read(APIC_LVTT);
+ v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+ apic_write_around(APIC_LVTT, v);
+ break;
+ }
local_irq_restore(flags);
}
+/*
+ * Local APIC timer broadcast function
+ */
+static void lapic_timer_broadcast(cpumask_t mask)
+{
+#ifdef CONFIG_SMP
+ send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
+#endif
+}
+
+/*
+ * Setup the local APIC timer for this CPU. Copy the initilized values
+ * of the boot CPU and register the clock event in the framework.
+ */
+static void __devinit setup_APIC_timer(void)
+{
+ struct clock_event_device *levt = &__get_cpu_var(lapic_events);
+
+ memcpy(levt, &lapic_clockevent, sizeof(*levt));
+ levt->cpumask = cpumask_of_cpu(smp_processor_id());
+
+ clockevents_register_device(levt);
+}
+
/*
* In this function we calibrate APIC bus clocks to the external
* timer. Unfortunately we cannot use jiffies and the timer irq
* to calibrate, since some later bootup code depends on getting
* the first irq? Ugh.
*
+ * TODO: Fix this rather than saying "Ugh" -tglx
+ *
* We want to do the calibration only once since we
* want to have local timer irqs syncron. CPUs connected
* by the same APIC bus have the very same bus frequency.
* value into the APIC clock, we just want to get the
* counter running for calibration.
*/
- __setup_APIC_LVTT(1000000000);
+ __setup_APIC_LVTT(1000000000, 0, 0);
/*
* The timer chip counts down to zero. Let's wait
result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
+ /* Calculate the scaled math multiplication factor */
+ lapic_clockevent.mult = div_sc(tt1-tt2, TICK_NSEC * LOOPS, 32);
+ lapic_clockevent.max_delta_ns =
+ clockevent_delta2ns(0x7FFFFF, &lapic_clockevent);
+ lapic_clockevent.min_delta_ns =
+ clockevent_delta2ns(0xF, &lapic_clockevent);
+
+ apic_printk(APIC_VERBOSE, "..... tt1-tt2 %ld\n", tt1 - tt2);
+ apic_printk(APIC_VERBOSE, "..... mult: %ld\n", lapic_clockevent.mult);
+ apic_printk(APIC_VERBOSE, "..... calibration result: %ld\n", result);
+
if (cpu_has_tsc)
apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
"%ld.%04ld MHz.\n",
return result;
}
-static unsigned int calibration_result;
-
void __init setup_boot_APIC_clock(void)
{
unsigned long flags;
apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
- using_apic_timer = 1;
local_irq_save(flags);
/*
* Now set up the timer for real.
*/
- setup_APIC_timer(calibration_result);
+ setup_APIC_timer();
local_irq_restore(flags);
}
void __devinit setup_secondary_APIC_clock(void)
{
- setup_APIC_timer(calibration_result);
-}
-
-void disable_APIC_timer(void)
-{
- if (using_apic_timer) {
- unsigned long v;
-
- v = apic_read(APIC_LVTT);
- /*
- * When an illegal vector value (0-15) is written to an LVT
- * entry and delivery mode is Fixed, the APIC may signal an
- * illegal vector error, with out regard to whether the mask
- * bit is set or whether an interrupt is actually seen on
- * input.
- *
- * Boot sequence might call this function when the LVTT has
- * '0' vector value. So make sure vector field is set to
- * valid value.
- */
- v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
- apic_write_around(APIC_LVTT, v);
- }
-}
-
-void enable_APIC_timer(void)
-{
- int cpu = smp_processor_id();
-
- if (using_apic_timer && !cpu_isset(cpu, timer_bcast_ipi)) {
- unsigned long v;
-
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
- }
-}
-
-void switch_APIC_timer_to_ipi(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
-
- if (cpu_isset(cpu, mask) &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- disable_APIC_timer();
- cpu_set(cpu, timer_bcast_ipi);
- }
-}
-EXPORT_SYMBOL(switch_APIC_timer_to_ipi);
-
-void switch_ipi_to_APIC_timer(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
-
- if (cpu_isset(cpu, mask) &&
- cpu_isset(cpu, timer_bcast_ipi)) {
- cpu_clear(cpu, timer_bcast_ipi);
- enable_APIC_timer();
- }
+ setup_APIC_timer();
}
-EXPORT_SYMBOL(switch_ipi_to_APIC_timer);
/*
- * Local timer interrupt handler. It does both profiling and
- * process statistics/rescheduling.
+ * The guts of the apic timer interrupt
*/
-inline void smp_local_timer_interrupt(void)
+static void local_apic_timer_interrupt(void)
{
- profile_tick(CPU_PROFILING);
-#ifdef CONFIG_SMP
- update_process_times(user_mode_vm(get_irq_regs()));
-#endif
+ int cpu = smp_processor_id();
+ struct clock_event_device *evt = &per_cpu(lapic_events, cpu);
/*
- * We take the 'long' return path, and there every subsystem
- * grabs the apropriate locks (kernel lock/ irq lock).
+ * Normally we should not be here till LAPIC has been
+ * initialized but in some cases like kdump, its possible that
+ * there is a pending LAPIC timer interrupt from previous
+ * kernel's context and is delivered in new kernel the moment
+ * interrupts are enabled.
*
- * we might want to decouple profiling from the 'long path',
- * and do the profiling totally in assembly.
- *
- * Currently this isn't too much of an issue (performance wise),
- * we can take more than 100K local irqs per second on a 100 MHz P5.
+ * Interrupts are enabled early and LAPIC is setup much later,
+ * hence its possible that when we get here evt->event_handler
+ * is NULL. Check for event_handler being NULL and discard
+ * the interrupt as spurious.
*/
+ if (!evt->event_handler) {
+ printk(KERN_WARNING
+ "Spurious LAPIC timer interrupt on cpu %d\n", cpu);
+ /* Switch it off */
+ lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
+ return;
+ }
+
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;
+
+ evt->event_handler(evt);
}
/*
* interrupt as well. Thus we cannot inline the local irq ... ]
*/
-fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
+void fastcall smp_apic_timer_interrupt(struct pt_regs *regs)
{
struct pt_regs *old_regs = set_irq_regs(regs);
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
/*
* NOTE! We'd better ACK the irq immediately,
*/
exit_idle();
irq_enter();
- smp_local_timer_interrupt();
+ local_apic_timer_interrupt();
irq_exit();
- set_irq_regs(old_regs);
-}
-#ifndef CONFIG_SMP
-static void up_apic_timer_interrupt_call(void)
-{
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
-
- smp_local_timer_interrupt();
-}
-#endif
-
-void smp_send_timer_broadcast_ipi(void)
-{
- cpumask_t mask;
-
- cpus_and(mask, cpu_online_map, timer_bcast_ipi);
- if (!cpus_empty(mask)) {
-#ifdef CONFIG_SMP
- send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
-#else
- /*
- * We can directly call the apic timer interrupt handler
- * in UP case. Minus all irq related functions
- */
- up_apic_timer_interrupt_call();
-#endif
- }
+ set_irq_regs(old_regs);
}
int setup_profiling_timer(unsigned int multiplier)
printk(KERN_INFO "No ESR for 82489DX.\n");
}
+ /* Disable the local apic timer */
+ value = apic_read(APIC_LVTT);
+ value |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+ apic_write_around(APIC_LVTT, value);
+
setup_apic_nmi_watchdog(NULL);
apic_pm_activate();
}
}
early_param("nolapic", parse_nolapic);
+static int __init apic_enable_lapic_timer(char *str)
+{
+ enable_local_apic_timer = 1;
+ return 0;
+}
+early_param("lapictimer", apic_enable_lapic_timer);
+
static int __init apic_set_verbosity(char *str)
{
if (strcmp("debug", str) == 0)
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
-fastcall void smp_spurious_interrupt(struct pt_regs *regs)
+void smp_spurious_interrupt(struct pt_regs *regs)
{
unsigned long v;
/*
* This interrupt should never happen with our APIC/SMP architecture
*/
-fastcall void smp_error_interrupt(struct pt_regs *regs)
+void smp_error_interrupt(struct pt_regs *regs)
{
unsigned long v, v1;
#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <linux/errno.h>
#include <linux/hpet.h>
#include <linux/init.h>
#include <asm/hpet.h>
#include <asm/io.h>
+extern struct clock_event_device *global_clock_event;
+
#define HPET_MASK CLOCKSOURCE_MASK(32)
#define HPET_SHIFT 22
/* FSEC = 10^-15 NSEC = 10^-9 */
#define FSEC_PER_NSEC 1000000
-static void __iomem *hpet_ptr;
+/*
+ * HPET address is set in acpi/boot.c, when an ACPI entry exists
+ */
+unsigned long hpet_address;
+static void __iomem * hpet_virt_address;
+
+static inline unsigned long hpet_readl(unsigned long a)
+{
+ return readl(hpet_virt_address + a);
+}
+
+static inline void hpet_writel(unsigned long d, unsigned long a)
+{
+ writel(d, hpet_virt_address + a);
+}
+
+/*
+ * HPET command line enable / disable
+ */
+static int boot_hpet_disable;
+
+static int __init hpet_setup(char* str)
+{
+ if (str) {
+ if (!strncmp("disable", str, 7))
+ boot_hpet_disable = 1;
+ }
+ return 1;
+}
+__setup("hpet=", hpet_setup);
+
+static inline int is_hpet_capable(void)
+{
+ return (!boot_hpet_disable && hpet_address);
+}
+
+/*
+ * HPET timer interrupt enable / disable
+ */
+static int hpet_legacy_int_enabled;
+
+/**
+ * is_hpet_enabled - check whether the hpet timer interrupt is enabled
+ */
+int is_hpet_enabled(void)
+{
+ return is_hpet_capable() && hpet_legacy_int_enabled;
+}
+
+/*
+ * When the hpet driver (/dev/hpet) is enabled, we need to reserve
+ * timer 0 and timer 1 in case of RTC emulation.
+ */
+#ifdef CONFIG_HPET
+static void hpet_reserve_platform_timers(unsigned long id)
+{
+ struct hpet __iomem *hpet = hpet_virt_address;
+ 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;
+
+ memset(&hd, 0, sizeof (hd));
+ hd.hd_phys_address = hpet_address;
+ hd.hd_address = hpet_virt_address;
+ hd.hd_nirqs = nrtimers;
+ hd.hd_flags = HPET_DATA_PLATFORM;
+ hpet_reserve_timer(&hd, 0);
+
+#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;
+
+ for (i = 2; i < nrtimers; timer++, i++)
+ hd.hd_irq[i] = (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) { }
+#endif
+
+/*
+ * Common hpet info
+ */
+static unsigned long hpet_period;
+
+static void hpet_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt);
+static int hpet_next_event(unsigned long delta,
+ struct clock_event_device *evt);
+
+/*
+ * The hpet clock event device
+ */
+static struct clock_event_device hpet_clockevent = {
+ .name = "hpet",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = hpet_set_mode,
+ .set_next_event = hpet_next_event,
+ .shift = 32,
+ .irq = 0,
+};
+
+static void hpet_start_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);
+ cfg |= HPET_CFG_ENABLE;
+ hpet_writel(cfg, HPET_CFG);
+}
+
+static void hpet_enable_int(void)
+{
+ unsigned long cfg = hpet_readl(HPET_CFG);
+
+ cfg |= HPET_CFG_LEGACY;
+ hpet_writel(cfg, HPET_CFG);
+ hpet_legacy_int_enabled = 1;
+}
+
+static void hpet_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ unsigned long cfg, cmp, now;
+ uint64_t delta;
+
+ switch(mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ delta = ((uint64_t)(NSEC_PER_SEC/HZ)) * hpet_clockevent.mult;
+ delta >>= hpet_clockevent.shift;
+ now = hpet_readl(HPET_COUNTER);
+ cmp = now + (unsigned long) delta;
+ cfg = hpet_readl(HPET_T0_CFG);
+ cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC |
+ HPET_TN_SETVAL | HPET_TN_32BIT;
+ hpet_writel(cfg, HPET_T0_CFG);
+ /*
+ * 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_T0_CMP);
+ udelay(1);
+ hpet_writel((unsigned long) delta, HPET_T0_CMP);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ cfg = hpet_readl(HPET_T0_CFG);
+ cfg &= ~HPET_TN_PERIODIC;
+ cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
+ hpet_writel(cfg, HPET_T0_CFG);
+ break;
+
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ cfg = hpet_readl(HPET_T0_CFG);
+ cfg &= ~HPET_TN_ENABLE;
+ hpet_writel(cfg, HPET_T0_CFG);
+ break;
+ }
+}
+
+static int hpet_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ unsigned long cnt;
+
+ cnt = hpet_readl(HPET_COUNTER);
+ cnt += delta;
+ hpet_writel(cnt, HPET_T0_CMP);
+
+ return ((long)(hpet_readl(HPET_COUNTER) - cnt ) > 0);
+}
+
+/*
+ * Try to setup the HPET timer
+ */
+int __init hpet_enable(void)
+{
+ unsigned long id;
+ uint64_t hpet_freq;
+
+ if (!is_hpet_capable())
+ return 0;
+
+ hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
+
+ /*
+ * Read the period and check for a sane value:
+ */
+ hpet_period = hpet_readl(HPET_PERIOD);
+ if (hpet_period < HPET_MIN_PERIOD || hpet_period > HPET_MAX_PERIOD)
+ goto out_nohpet;
+
+ /*
+ * The period is a femto seconds value. We need to calculate the
+ * scaled math multiplication factor for nanosecond to hpet tick
+ * conversion.
+ */
+ hpet_freq = 1000000000000000ULL;
+ do_div(hpet_freq, hpet_period);
+ hpet_clockevent.mult = div_sc((unsigned long) hpet_freq,
+ NSEC_PER_SEC, 32);
+ /* 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);
+
+ /*
+ * Read the HPET ID register to retrieve the IRQ routing
+ * information and the number of channels
+ */
+ id = hpet_readl(HPET_ID);
+
+#ifdef CONFIG_HPET_EMULATE_RTC
+ /*
+ * The legacy routing mode needs at least two channels, tick timer
+ * and the rtc emulation channel.
+ */
+ if (!(id & HPET_ID_NUMBER))
+ goto out_nohpet;
+#endif
+
+ /* Start the counter */
+ hpet_start_counter();
+
+ if (id & HPET_ID_LEGSUP) {
+ hpet_enable_int();
+ hpet_reserve_platform_timers(id);
+ /*
+ * 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);
+ clockevents_register_device(&hpet_clockevent);
+ global_clock_event = &hpet_clockevent;
+ return 1;
+ }
+ return 0;
+out_nohpet:
+ iounmap(hpet_virt_address);
+ hpet_virt_address = NULL;
+ return 0;
+}
+
+/*
+ * Clock source related code
+ */
static cycle_t read_hpet(void)
{
- return (cycle_t)readl(hpet_ptr);
+ return (cycle_t)hpet_readl(HPET_COUNTER);
}
static struct clocksource clocksource_hpet = {
.rating = 250,
.read = read_hpet,
.mask = HPET_MASK,
- .mult = 0, /* set below */
.shift = HPET_SHIFT,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
static int __init init_hpet_clocksource(void)
{
- unsigned long hpet_period;
- void __iomem* hpet_base;
u64 tmp;
- int err;
- if (!is_hpet_enabled())
+ if (!hpet_virt_address)
return -ENODEV;
- /* calculate the hpet address: */
- hpet_base = ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
- hpet_ptr = hpet_base + HPET_COUNTER;
-
- /* calculate the frequency: */
- hpet_period = readl(hpet_base + HPET_PERIOD);
-
/*
* hpet period is in femto seconds per cycle
* so we need to convert this to ns/cyc units
do_div(tmp, FSEC_PER_NSEC);
clocksource_hpet.mult = (u32)tmp;
- err = clocksource_register(&clocksource_hpet);
- if (err)
- iounmap(hpet_base);
-
- return err;
+ return clocksource_register(&clocksource_hpet);
}
module_init(init_hpet_clocksource);
+
+#ifdef CONFIG_HPET_EMULATE_RTC
+
+/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET
+ * is enabled, we support RTC interrupt functionality in software.
+ * RTC has 3 kinds of interrupts:
+ * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock
+ * is updated
+ * 2) Alarm Interrupt - generate an interrupt at a specific time of day
+ * 3) Periodic Interrupt - generate periodic interrupt, with frequencies
+ * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2)
+ * (1) and (2) above are implemented using polling at a frequency of
+ * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt
+ * overhead. (DEFAULT_RTC_INT_FREQ)
+ * For (3), we use interrupts at 64Hz or user specified periodic
+ * frequency, whichever is higher.
+ */
+#include <linux/mc146818rtc.h>
+#include <linux/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 struct rtc_time hpet_alarm_time;
+static unsigned long hpet_pie_count;
+static unsigned long hpet_t1_cmp;
+static unsigned long hpet_default_delta;
+static unsigned long hpet_pie_delta;
+static unsigned long hpet_pie_limit;
+
+/*
+ * Timer 1 for RTC emulation. We use one shot mode, as periodic mode
+ * is not supported by all HPET implementations for timer 1.
+ *
+ * hpet_rtc_timer_init() is called when the rtc is initialized.
+ */
+int hpet_rtc_timer_init(void)
+{
+ unsigned long cfg, cnt, delta, flags;
+
+ if (!is_hpet_enabled())
+ return 0;
+
+ if (!hpet_default_delta) {
+ uint64_t clc;
+
+ clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC;
+ clc >>= hpet_clockevent.shift + DEFAULT_RTC_SHIFT;
+ hpet_default_delta = (unsigned long) clc;
+ }
+
+ if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit)
+ delta = hpet_default_delta;
+ else
+ delta = hpet_pie_delta;
+
+ local_irq_save(flags);
+
+ cnt = delta + hpet_readl(HPET_COUNTER);
+ hpet_writel(cnt, HPET_T1_CMP);
+ hpet_t1_cmp = cnt;
+
+ cfg = hpet_readl(HPET_T1_CFG);
+ cfg &= ~HPET_TN_PERIODIC;
+ cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
+ hpet_writel(cfg, HPET_T1_CFG);
+
+ local_irq_restore(flags);
+
+ return 1;
+}
+
+/*
+ * The functions below are called from rtc driver.
+ * Return 0 if HPET is not being used.
+ * Otherwise do the necessary changes and return 1.
+ */
+int hpet_mask_rtc_irq_bit(unsigned long bit_mask)
+{
+ if (!is_hpet_enabled())
+ return 0;
+
+ hpet_rtc_flags &= ~bit_mask;
+ return 1;
+}
+
+int hpet_set_rtc_irq_bit(unsigned long bit_mask)
+{
+ unsigned long oldbits = hpet_rtc_flags;
+
+ if (!is_hpet_enabled())
+ return 0;
+
+ hpet_rtc_flags |= bit_mask;
+
+ if (!oldbits)
+ hpet_rtc_timer_init();
+
+ return 1;
+}
+
+int hpet_set_alarm_time(unsigned char hrs, unsigned char min,
+ unsigned char sec)
+{
+ if (!is_hpet_enabled())
+ return 0;
+
+ hpet_alarm_time.tm_hour = hrs;
+ hpet_alarm_time.tm_min = min;
+ hpet_alarm_time.tm_sec = sec;
+
+ return 1;
+}
+
+int hpet_set_periodic_freq(unsigned long freq)
+{
+ uint64_t clc;
+
+ if (!is_hpet_enabled())
+ return 0;
+
+ if (freq <= DEFAULT_RTC_INT_FREQ)
+ hpet_pie_limit = DEFAULT_RTC_INT_FREQ / freq;
+ else {
+ clc = (uint64_t) hpet_clockevent.mult * NSEC_PER_SEC;
+ do_div(clc, freq);
+ clc >>= hpet_clockevent.shift;
+ hpet_pie_delta = (unsigned long) clc;
+ }
+ return 1;
+}
+
+int hpet_rtc_dropped_irq(void)
+{
+ return is_hpet_enabled();
+}
+
+static void hpet_rtc_timer_reinit(void)
+{
+ unsigned long cfg, delta;
+ int lost_ints = -1;
+
+ if (unlikely(!hpet_rtc_flags)) {
+ cfg = hpet_readl(HPET_T1_CFG);
+ cfg &= ~HPET_TN_ENABLE;
+ hpet_writel(cfg, HPET_T1_CFG);
+ return;
+ }
+
+ if (!(hpet_rtc_flags & RTC_PIE) || hpet_pie_limit)
+ delta = hpet_default_delta;
+ else
+ delta = hpet_pie_delta;
+
+ /*
+ * Increment the comparator value until we are ahead of the
+ * current count.
+ */
+ do {
+ hpet_t1_cmp += delta;
+ hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
+ lost_ints++;
+ } while ((long)(hpet_readl(HPET_COUNTER) - hpet_t1_cmp) > 0);
+
+ if (lost_ints) {
+ if (hpet_rtc_flags & RTC_PIE)
+ hpet_pie_count += lost_ints;
+ if (printk_ratelimit())
+ printk(KERN_WARNING "rtc: lost %d interrupts\n",
+ lost_ints);
+ }
+}
+
+irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
+{
+ struct rtc_time curr_time;
+ unsigned long rtc_int_flag = 0;
+
+ hpet_rtc_timer_reinit();
+
+ if (hpet_rtc_flags & (RTC_UIE | RTC_AIE))
+ rtc_get_rtc_time(&curr_time);
+
+ if (hpet_rtc_flags & RTC_UIE &&
+ curr_time.tm_sec != hpet_prev_update_sec) {
+ rtc_int_flag = RTC_UF;
+ hpet_prev_update_sec = curr_time.tm_sec;
+ }
+
+ if (hpet_rtc_flags & RTC_PIE &&
+ ++hpet_pie_count >= hpet_pie_limit) {
+ rtc_int_flag |= RTC_PF;
+ hpet_pie_count = 0;
+ }
+
+ if (hpet_rtc_flags & RTC_PIE &&
+ (curr_time.tm_sec == hpet_alarm_time.tm_sec) &&
+ (curr_time.tm_min == hpet_alarm_time.tm_min) &&
+ (curr_time.tm_hour == hpet_alarm_time.tm_hour))
+ rtc_int_flag |= RTC_AF;
+
+ if (rtc_int_flag) {
+ rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8));
+ rtc_interrupt(rtc_int_flag, dev_id);
+ }
+ return IRQ_HANDLED;
+}
+#endif
* i8253.c 8253/PIT functions
*
*/
-#include <linux/clocksource.h>
+#include <linux/clockchips.h>
#include <linux/spinlock.h>
#include <linux/jiffies.h>
#include <linux/sysdev.h>
DEFINE_SPINLOCK(i8253_lock);
EXPORT_SYMBOL(i8253_lock);
-void setup_pit_timer(void)
+/*
+ * HPET replaces the PIT, when enabled. So we need to know, which of
+ * the two timers is used
+ */
+struct clock_event_device *global_clock_event;
+
+/*
+ * Initialize the PIT timer.
+ *
+ * This is also called after resume to bring the PIT into operation again.
+ */
+static void init_pit_timer(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&i8253_lock, flags);
+
+ switch(mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ /* binary, mode 2, LSB/MSB, ch 0 */
+ outb_p(0x34, PIT_MODE);
+ udelay(10);
+ outb_p(LATCH & 0xff , PIT_CH0); /* LSB */
+ udelay(10);
+ outb(LATCH >> 8 , PIT_CH0); /* MSB */
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+ /* One shot setup */
+ outb_p(0x38, PIT_MODE);
+ udelay(10);
+ break;
+ }
+ spin_unlock_irqrestore(&i8253_lock, flags);
+}
+
+/*
+ * Program the next event in oneshot mode
+ *
+ * Delta is given in PIT ticks
+ */
+static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
{
unsigned long flags;
spin_lock_irqsave(&i8253_lock, flags);
- outb_p(0x34,PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
- udelay(10);
- outb_p(LATCH & 0xff , PIT_CH0); /* LSB */
- udelay(10);
- outb(LATCH >> 8 , PIT_CH0); /* MSB */
+ outb_p(delta & 0xff , PIT_CH0); /* LSB */
+ outb(delta >> 8 , PIT_CH0); /* MSB */
spin_unlock_irqrestore(&i8253_lock, flags);
+
+ return 0;
+}
+
+/*
+ * On UP the PIT can serve all of the possible timer functions. On SMP systems
+ * it can be solely used for the global tick.
+ *
+ * The profiling and update capabilites are switched off once the local apic is
+ * registered. This mechanism replaces the previous #ifdef LOCAL_APIC -
+ * !using_apic_timer decisions in do_timer_interrupt_hook()
+ */
+struct clock_event_device pit_clockevent = {
+ .name = "pit",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .set_mode = init_pit_timer,
+ .set_next_event = pit_next_event,
+ .shift = 32,
+ .irq = 0,
+};
+
+/*
+ * Initialize the conversion factor and the min/max deltas of the clock event
+ * structure and register the clock event source with the framework.
+ */
+void __init setup_pit_timer(void)
+{
+ /*
+ * Start pit with the boot cpu mask and make it global after the
+ * IO_APIC has been initialized.
+ */
+ pit_clockevent.cpumask = cpumask_of_cpu(0);
+ pit_clockevent.mult = div_sc(CLOCK_TICK_RATE, NSEC_PER_SEC, 32);
+ pit_clockevent.max_delta_ns =
+ clockevent_delta2ns(0x7FFF, &pit_clockevent);
+ pit_clockevent.min_delta_ns =
+ clockevent_delta2ns(0xF, &pit_clockevent);
+ clockevents_register_device(&pit_clockevent);
+ global_clock_event = &pit_clockevent;
}
/*
static u32 old_jifs;
spin_lock_irqsave(&i8253_lock, flags);
- /*
+ /*
* Although our caller may have the read side of xtime_lock,
* this is now a seqlock, and we are cheating in this routine
* by having side effects on state that we cannot undo if
*/
intr_init_hook();
- /*
- * Set the clock to HZ Hz, we already have a valid
- * vector now:
- */
- setup_pit_timer();
-
/*
* External FPU? Set up irq13 if so, for
* original braindamaged IBM FERR coupling.
/*
* Save our processor parameters
*/
- smp_store_cpu_info(cpuid);
-
- disable_APIC_timer();
+ smp_store_cpu_info(cpuid);
/*
* Allow the master to continue.
enable_NMI_through_LVT0(NULL);
enable_8259A_irq(0);
}
- enable_APIC_timer();
/*
* low-memory mappings have been cleared, flush them from
* the local TLBs too.
*/
irqreturn_t timer_interrupt(int irq, void *dev_id)
{
- /*
- * Here we are in the timer irq handler. We just have irqs locally
- * disabled but we don't know if the timer_bh is running on the other
- * CPU. We need to avoid to SMP race with it. NOTE: we don' t need
- * the irq version of write_lock because as just said we have irq
- * locally disabled. -arca
- */
- write_seqlock(&xtime_lock);
-
#ifdef CONFIG_X86_IO_APIC
if (timer_ack) {
/*
do_timer_interrupt_hook();
-
if (MCA_bus) {
/* The PS/2 uses level-triggered interrupts. You can't
turn them off, nor would you want to (any attempt to
outb_p( irq_v|0x80, 0x61 ); /* reset the IRQ */
}
- write_sequnlock(&xtime_lock);
-
-#ifdef CONFIG_X86_LOCAL_APIC
- if (using_apic_timer)
- smp_send_timer_broadcast_ipi();
-#endif
-
return IRQ_HANDLED;
}
mod_timer(&sync_cmos_timer, jiffies + 1);
}
-static int timer_resume(struct sys_device *dev)
-{
-#ifdef CONFIG_HPET_TIMER
- if (is_hpet_enabled())
- hpet_reenable();
-#endif
- setup_pit_timer();
- touch_softlockup_watchdog();
- return 0;
-}
-
-static struct sysdev_class timer_sysclass = {
- .resume = timer_resume,
- set_kset_name("timer"),
-};
-
-
-/* XXX this driverfs stuff should probably go elsewhere later -john */
-static struct sys_device device_timer = {
- .id = 0,
- .cls = &timer_sysclass,
-};
-
-static int time_init_device(void)
-{
- int error = sysdev_class_register(&timer_sysclass);
- if (!error)
- error = sysdev_register(&device_timer);
- return error;
-}
-
-device_initcall(time_init_device);
-
-#ifdef CONFIG_HPET_TIMER
extern void (*late_time_init)(void);
/* Duplicate of time_init() below, with hpet_enable part added */
static void __init hpet_time_init(void)
{
- if ((hpet_enable() >= 0) && hpet_use_timer) {
- printk("Using HPET for base-timer\n");
- }
-
+ if (!hpet_enable())
+ setup_pit_timer();
do_time_init();
}
-#endif
void __init time_init(void)
{
-#ifdef CONFIG_HPET_TIMER
- if (is_hpet_capable()) {
- /*
- * HPET initialization needs to do memory-mapped io. So, let
- * us do a late initialization after mem_init().
- */
- late_time_init = hpet_time_init;
- return;
- }
-#endif
- do_time_init();
+ late_time_init = hpet_time_init;
}
+++ /dev/null
-/*
- * linux/arch/i386/kernel/time_hpet.c
- * This code largely copied from arch/x86_64/kernel/time.c
- * See that file for credits.
- *
- * 2003-06-30 Venkatesh Pallipadi - Additional changes for HPET support
- */
-
-#include <linux/errno.h>
-#include <linux/kernel.h>
-#include <linux/param.h>
-#include <linux/string.h>
-#include <linux/init.h>
-#include <linux/smp.h>
-
-#include <asm/timer.h>
-#include <asm/fixmap.h>
-#include <asm/apic.h>
-
-#include <linux/timex.h>
-
-#include <asm/hpet.h>
-#include <linux/hpet.h>
-
-static unsigned long hpet_period; /* fsecs / HPET clock */
-unsigned long hpet_tick; /* hpet clks count per tick */
-unsigned long hpet_address; /* hpet memory map physical address */
-int hpet_use_timer;
-
-static int use_hpet; /* can be used for runtime check of hpet */
-static int boot_hpet_disable; /* boottime override for HPET timer */
-static void __iomem * hpet_virt_address; /* hpet kernel virtual address */
-
-#define FSEC_TO_USEC (1000000000UL)
-
-int hpet_readl(unsigned long a)
-{
- return readl(hpet_virt_address + a);
-}
-
-static void hpet_writel(unsigned long d, unsigned long a)
-{
- writel(d, hpet_virt_address + a);
-}
-
-#ifdef CONFIG_X86_LOCAL_APIC
-/*
- * HPET counters dont wrap around on every tick. They just change the
- * comparator value and continue. Next tick can be caught by checking
- * for a change in the comparator value. Used in apic.c.
- */
-static void __devinit wait_hpet_tick(void)
-{
- unsigned int start_cmp_val, end_cmp_val;
-
- start_cmp_val = hpet_readl(HPET_T0_CMP);
- do {
- end_cmp_val = hpet_readl(HPET_T0_CMP);
- } while (start_cmp_val == end_cmp_val);
-}
-#endif
-
-static int hpet_timer_stop_set_go(unsigned long tick)
-{
- unsigned int cfg;
-
- /*
- * Stop the timers and reset the main counter.
- */
- 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);
-
- if (hpet_use_timer) {
- /*
- * Set up timer 0, as periodic with first interrupt to happen at
- * hpet_tick, and period also hpet_tick.
- */
- cfg = hpet_readl(HPET_T0_CFG);
- cfg |= HPET_TN_ENABLE | HPET_TN_PERIODIC |
- HPET_TN_SETVAL | HPET_TN_32BIT;
- hpet_writel(cfg, HPET_T0_CFG);
-
- /*
- * The first write after writing TN_SETVAL to the config register sets
- * the counter value, the second write sets the threshold.
- */
- hpet_writel(tick, HPET_T0_CMP);
- hpet_writel(tick, HPET_T0_CMP);
- }
- /*
- * Go!
- */
- cfg = hpet_readl(HPET_CFG);
- if (hpet_use_timer)
- cfg |= HPET_CFG_LEGACY;
- cfg |= HPET_CFG_ENABLE;
- hpet_writel(cfg, HPET_CFG);
-
- return 0;
-}
-
-/*
- * Check whether HPET was found by ACPI boot parse. If yes setup HPET
- * counter 0 for kernel base timer.
- */
-int __init hpet_enable(void)
-{
- unsigned int id;
- unsigned long tick_fsec_low, tick_fsec_high; /* tick in femto sec */
- unsigned long hpet_tick_rem;
-
- if (boot_hpet_disable)
- return -1;
-
- if (!hpet_address) {
- return -1;
- }
- hpet_virt_address = ioremap_nocache(hpet_address, HPET_MMAP_SIZE);
- /*
- * Read the period, compute tick and quotient.
- */
- id = hpet_readl(HPET_ID);
-
- /*
- * We are checking for value '1' or more in number field if
- * CONFIG_HPET_EMULATE_RTC is set because we will need an
- * additional timer for RTC emulation.
- * However, we can do with one timer otherwise using the
- * the single HPET timer for system time.
- */
-#ifdef CONFIG_HPET_EMULATE_RTC
- if (!(id & HPET_ID_NUMBER)) {
- iounmap(hpet_virt_address);
- hpet_virt_address = NULL;
- return -1;
- }
-#endif
-
-
- hpet_period = hpet_readl(HPET_PERIOD);
- if ((hpet_period < HPET_MIN_PERIOD) || (hpet_period > HPET_MAX_PERIOD)) {
- iounmap(hpet_virt_address);
- hpet_virt_address = NULL;
- return -1;
- }
-
- /*
- * 64 bit math
- * First changing tick into fsec
- * Then 64 bit div to find number of hpet clk per tick
- */
- ASM_MUL64_REG(tick_fsec_low, tick_fsec_high,
- KERNEL_TICK_USEC, FSEC_TO_USEC);
- ASM_DIV64_REG(hpet_tick, hpet_tick_rem,
- hpet_period, tick_fsec_low, tick_fsec_high);
-
- if (hpet_tick_rem > (hpet_period >> 1))
- hpet_tick++; /* rounding the result */
-
- hpet_use_timer = id & HPET_ID_LEGSUP;
-
- if (hpet_timer_stop_set_go(hpet_tick)) {
- iounmap(hpet_virt_address);
- hpet_virt_address = NULL;
- return -1;
- }
-
- use_hpet = 1;
-
-#ifdef CONFIG_HPET
- {
- struct hpet_data hd;
- unsigned int ntimer;
-
- memset(&hd, 0, sizeof (hd));
-
- ntimer = hpet_readl(HPET_ID);
- ntimer = (ntimer & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT;
- ntimer++;
-
- /*
- * Register with driver.
- * Timer0 and Timer1 is used by platform.
- */
- hd.hd_phys_address = hpet_address;
- hd.hd_address = hpet_virt_address;
- hd.hd_nirqs = ntimer;
- hd.hd_flags = HPET_DATA_PLATFORM;
- hpet_reserve_timer(&hd, 0);
-#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;
- if (ntimer > 2) {
- struct hpet __iomem *hpet;
- struct hpet_timer __iomem *timer;
- int i;
-
- hpet = hpet_virt_address;
-
- for (i = 2, timer = &hpet->hpet_timers[2]; i < ntimer;
- timer++, i++)
- hd.hd_irq[i] = (timer->hpet_config &
- Tn_INT_ROUTE_CNF_MASK) >>
- Tn_INT_ROUTE_CNF_SHIFT;
-
- }
-
- hpet_alloc(&hd);
- }
-#endif
-
-#ifdef CONFIG_X86_LOCAL_APIC
- if (hpet_use_timer)
- wait_timer_tick = wait_hpet_tick;
-#endif
- return 0;
-}
-
-int hpet_reenable(void)
-{
- return hpet_timer_stop_set_go(hpet_tick);
-}
-
-int is_hpet_enabled(void)
-{
- return use_hpet;
-}
-
-int is_hpet_capable(void)
-{
- if (!boot_hpet_disable && hpet_address)
- return 1;
- return 0;
-}
-
-static int __init hpet_setup(char* str)
-{
- if (str) {
- if (!strncmp("disable", str, 7))
- boot_hpet_disable = 1;
- }
- return 1;
-}
-
-__setup("hpet=", hpet_setup);
-
-#ifdef CONFIG_HPET_EMULATE_RTC
-/* HPET in LegacyReplacement Mode eats up RTC interrupt line. When, HPET
- * is enabled, we support RTC interrupt functionality in software.
- * RTC has 3 kinds of interrupts:
- * 1) Update Interrupt - generate an interrupt, every sec, when RTC clock
- * is updated
- * 2) Alarm Interrupt - generate an interrupt at a specific time of day
- * 3) Periodic Interrupt - generate periodic interrupt, with frequencies
- * 2Hz-8192Hz (2Hz-64Hz for non-root user) (all freqs in powers of 2)
- * (1) and (2) above are implemented using polling at a frequency of
- * 64 Hz. The exact frequency is a tradeoff between accuracy and interrupt
- * overhead. (DEFAULT_RTC_INT_FREQ)
- * For (3), we use interrupts at 64Hz or user specified periodic
- * frequency, whichever is higher.
- */
-#include <linux/mc146818rtc.h>
-#include <linux/rtc.h>
-
-#define DEFAULT_RTC_INT_FREQ 64
-#define RTC_NUM_INTS 1
-
-static unsigned long UIE_on;
-static unsigned long prev_update_sec;
-
-static unsigned long AIE_on;
-static struct rtc_time alarm_time;
-
-static unsigned long PIE_on;
-static unsigned long PIE_freq = DEFAULT_RTC_INT_FREQ;
-static unsigned long PIE_count;
-
-static unsigned long hpet_rtc_int_freq; /* RTC interrupt frequency */
-static unsigned int hpet_t1_cmp; /* cached comparator register */
-
-/*
- * Timer 1 for RTC, we do not use periodic interrupt feature,
- * even if HPET supports periodic interrupts on Timer 1.
- * The reason being, to set up a periodic interrupt in HPET, we need to
- * stop the main counter. And if we do that everytime someone diables/enables
- * RTC, we will have adverse effect on main kernel timer running on Timer 0.
- * So, for the time being, simulate the periodic interrupt in software.
- *
- * hpet_rtc_timer_init() is called for the first time and during subsequent
- * interuppts reinit happens through hpet_rtc_timer_reinit().
- */
-int hpet_rtc_timer_init(void)
-{
- unsigned int cfg, cnt;
- unsigned long flags;
-
- if (!is_hpet_enabled())
- return 0;
- /*
- * Set the counter 1 and enable the interrupts.
- */
- if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
- hpet_rtc_int_freq = PIE_freq;
- else
- hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;
-
- local_irq_save(flags);
-
- cnt = hpet_readl(HPET_COUNTER);
- cnt += ((hpet_tick*HZ)/hpet_rtc_int_freq);
- hpet_writel(cnt, HPET_T1_CMP);
- hpet_t1_cmp = cnt;
-
- cfg = hpet_readl(HPET_T1_CFG);
- cfg &= ~HPET_TN_PERIODIC;
- cfg |= HPET_TN_ENABLE | HPET_TN_32BIT;
- hpet_writel(cfg, HPET_T1_CFG);
-
- local_irq_restore(flags);
-
- return 1;
-}
-
-static void hpet_rtc_timer_reinit(void)
-{
- unsigned int cfg, cnt, ticks_per_int, lost_ints;
-
- if (unlikely(!(PIE_on | AIE_on | UIE_on))) {
- cfg = hpet_readl(HPET_T1_CFG);
- cfg &= ~HPET_TN_ENABLE;
- hpet_writel(cfg, HPET_T1_CFG);
- return;
- }
-
- if (PIE_on && (PIE_freq > DEFAULT_RTC_INT_FREQ))
- hpet_rtc_int_freq = PIE_freq;
- else
- hpet_rtc_int_freq = DEFAULT_RTC_INT_FREQ;
-
- /* It is more accurate to use the comparator value than current count.*/
- ticks_per_int = hpet_tick * HZ / hpet_rtc_int_freq;
- hpet_t1_cmp += ticks_per_int;
- hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
-
- /*
- * If the interrupt handler was delayed too long, the write above tries
- * to schedule the next interrupt in the past and the hardware would
- * not interrupt until the counter had wrapped around.
- * So we have to check that the comparator wasn't set to a past time.
- */
- cnt = hpet_readl(HPET_COUNTER);
- if (unlikely((int)(cnt - hpet_t1_cmp) > 0)) {
- lost_ints = (cnt - hpet_t1_cmp) / ticks_per_int + 1;
- /* Make sure that, even with the time needed to execute
- * this code, the next scheduled interrupt has been moved
- * back to the future: */
- lost_ints++;
-
- hpet_t1_cmp += lost_ints * ticks_per_int;
- hpet_writel(hpet_t1_cmp, HPET_T1_CMP);
-
- if (PIE_on)
- PIE_count += lost_ints;
-
- printk(KERN_WARNING "rtc: lost some interrupts at %ldHz.\n",
- hpet_rtc_int_freq);
- }
-}
-
-/*
- * The functions below are called from rtc driver.
- * Return 0 if HPET is not being used.
- * Otherwise do the necessary changes and return 1.
- */
-int hpet_mask_rtc_irq_bit(unsigned long bit_mask)
-{
- if (!is_hpet_enabled())
- return 0;
-
- if (bit_mask & RTC_UIE)
- UIE_on = 0;
- if (bit_mask & RTC_PIE)
- PIE_on = 0;
- if (bit_mask & RTC_AIE)
- AIE_on = 0;
-
- return 1;
-}
-
-int hpet_set_rtc_irq_bit(unsigned long bit_mask)
-{
- int timer_init_reqd = 0;
-
- if (!is_hpet_enabled())
- return 0;
-
- if (!(PIE_on | AIE_on | UIE_on))
- timer_init_reqd = 1;
-
- if (bit_mask & RTC_UIE) {
- UIE_on = 1;
- }
- if (bit_mask & RTC_PIE) {
- PIE_on = 1;
- PIE_count = 0;
- }
- if (bit_mask & RTC_AIE) {
- AIE_on = 1;
- }
-
- if (timer_init_reqd)
- hpet_rtc_timer_init();
-
- return 1;
-}
-
-int hpet_set_alarm_time(unsigned char hrs, unsigned char min, unsigned char sec)
-{
- if (!is_hpet_enabled())
- return 0;
-
- alarm_time.tm_hour = hrs;
- alarm_time.tm_min = min;
- alarm_time.tm_sec = sec;
-
- return 1;
-}
-
-int hpet_set_periodic_freq(unsigned long freq)
-{
- if (!is_hpet_enabled())
- return 0;
-
- PIE_freq = freq;
- PIE_count = 0;
-
- return 1;
-}
-
-int hpet_rtc_dropped_irq(void)
-{
- if (!is_hpet_enabled())
- return 0;
-
- return 1;
-}
-
-irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id)
-{
- struct rtc_time curr_time;
- unsigned long rtc_int_flag = 0;
- int call_rtc_interrupt = 0;
-
- hpet_rtc_timer_reinit();
-
- if (UIE_on | AIE_on) {
- rtc_get_rtc_time(&curr_time);
- }
- if (UIE_on) {
- if (curr_time.tm_sec != prev_update_sec) {
- /* Set update int info, call real rtc int routine */
- call_rtc_interrupt = 1;
- rtc_int_flag = RTC_UF;
- prev_update_sec = curr_time.tm_sec;
- }
- }
- if (PIE_on) {
- PIE_count++;
- if (PIE_count >= hpet_rtc_int_freq/PIE_freq) {
- /* Set periodic int info, call real rtc int routine */
- call_rtc_interrupt = 1;
- rtc_int_flag |= RTC_PF;
- PIE_count = 0;
- }
- }
- if (AIE_on) {
- if ((curr_time.tm_sec == alarm_time.tm_sec) &&
- (curr_time.tm_min == alarm_time.tm_min) &&
- (curr_time.tm_hour == alarm_time.tm_hour)) {
- /* Set alarm int info, call real rtc int routine */
- call_rtc_interrupt = 1;
- rtc_int_flag |= RTC_AF;
- }
- }
- if (call_rtc_interrupt) {
- rtc_int_flag |= (RTC_IRQF | (RTC_NUM_INTS << 8));
- rtc_interrupt(rtc_int_flag, dev_id);
- }
- return IRQ_HANDLED;
-}
-#endif
-
{
}
-static struct irqaction irq0 = { timer_interrupt, IRQF_DISABLED, CPU_MASK_NONE, "timer", NULL, NULL};
+static struct irqaction irq0 = {
+ .handler = timer_interrupt,
+ .flags = IRQF_DISABLED | IRQF_NOBALANCING,
+ .mask = CPU_MASK_NONE,
+ .name = "timer"
+};
/**
* time_init_hook - do any specific initialisations for the system timer.
**/
void __init time_init_hook(void)
{
+ irq0.mask = cpumask_of_cpu(0);
setup_irq(0, &irq0);
}
#include <linux/moduleparam.h>
#include <linux/sched.h> /* need_resched() */
#include <linux/latency.h>
+#include <linux/clockchips.h>
/*
* Include the apic definitions for x86 to have the APIC timer related defines
static void acpi_propagate_timer_broadcast(struct acpi_processor *pr)
{
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+ unsigned long reason;
+
+ reason = pr->power.timer_broadcast_on_state < INT_MAX ?
+ CLOCK_EVT_NOTIFY_BROADCAST_ON : CLOCK_EVT_NOTIFY_BROADCAST_OFF;
+
+ clockevents_notify(reason, &pr->id);
+#else
cpumask_t mask = cpumask_of_cpu(pr->id);
if (pr->power.timer_broadcast_on_state < INT_MAX)
on_each_cpu(switch_APIC_timer_to_ipi, &mask, 1, 1);
else
on_each_cpu(switch_ipi_to_APIC_timer, &mask, 1, 1);
+#endif
+}
+
+/* Power(C) State timer broadcast control */
+static void acpi_state_timer_broadcast(struct acpi_processor *pr,
+ struct acpi_processor_cx *cx,
+ int broadcast)
+{
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+
+ int state = cx - pr->power.states;
+
+ if (state >= pr->power.timer_broadcast_on_state) {
+ unsigned long reason;
+
+ reason = broadcast ? CLOCK_EVT_NOTIFY_BROADCAST_ENTER :
+ CLOCK_EVT_NOTIFY_BROADCAST_EXIT;
+ clockevents_notify(reason, &pr->id);
+ }
+#endif
}
#else
static void acpi_timer_check_state(int state, struct acpi_processor *pr,
struct acpi_processor_cx *cstate) { }
static void acpi_propagate_timer_broadcast(struct acpi_processor *pr) { }
+static void acpi_state_timer_broadcast(struct acpi_processor *pr,
+ struct acpi_processor_cx *cx,
+ int broadcast)
+{
+}
#endif
/* Get start time (ticks) */
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Invoke C2 */
+ acpi_state_timer_broadcast(pr, cx, 1);
acpi_cstate_enter(cx);
/* Get end time (ticks) */
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Compute time (ticks) that we were actually asleep */
sleep_ticks =
ticks_elapsed(t1, t2) - cx->latency_ticks - C2_OVERHEAD;
+ acpi_state_timer_broadcast(pr, cx, 0);
break;
case ACPI_STATE_C3:
/* Get start time (ticks) */
t1 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Invoke C3 */
+ acpi_state_timer_broadcast(pr, cx, 1);
acpi_cstate_enter(cx);
/* Get end time (ticks) */
t2 = inl(acpi_gbl_FADT.xpm_timer_block.address);
/* Compute time (ticks) that we were actually asleep */
sleep_ticks =
ticks_elapsed(t1, t2) - cx->latency_ticks - C3_OVERHEAD;
+ acpi_state_timer_broadcast(pr, cx, 0);
break;
default:
extern void setup_boot_APIC_clock (void);
extern void setup_secondary_APIC_clock (void);
extern int APIC_init_uniprocessor (void);
-extern void disable_APIC_timer(void);
-extern void enable_APIC_timer(void);
extern void enable_NMI_through_LVT0 (void * dummy);
-void smp_send_timer_broadcast_ipi(void);
-void switch_APIC_timer_to_ipi(void *cpumask);
-void switch_ipi_to_APIC_timer(void *cpumask);
#define ARCH_APICTIMER_STOPS_ON_C3 1
extern int timer_over_8254;
#define HPET_MIN_PERIOD (100000UL)
#define HPET_TICK_RATE (HZ * 100000UL)
-extern unsigned long hpet_tick; /* hpet clks count per tick */
extern unsigned long hpet_address; /* hpet memory map physical address */
-extern int hpet_use_timer;
+extern int is_hpet_enabled(void);
+#ifdef CONFIG_X86_64
+extern unsigned long hpet_tick; /* hpet clks count per tick */
+extern int hpet_use_timer;
extern int hpet_rtc_timer_init(void);
extern int hpet_enable(void);
-extern int hpet_reenable(void);
-extern int is_hpet_enabled(void);
extern int is_hpet_capable(void);
extern int hpet_readl(unsigned long a);
+#else
+extern int hpet_enable(void);
+#endif
#ifdef CONFIG_HPET_EMULATE_RTC
extern int hpet_mask_rtc_irq_bit(unsigned long bit_mask);
extern int hpet_rtc_timer_init(void);
extern irqreturn_t hpet_rtc_interrupt(int irq, void *dev_id);
#endif /* CONFIG_HPET_EMULATE_RTC */
+
+#else
+
+static inline int hpet_enable(void) { return 0; }
+
#endif /* CONFIG_HPET_TIMER */
#endif /* _I386_HPET_H */
#ifndef __ASM_I8253_H__
#define __ASM_I8253_H__
+#include <linux/clockchips.h>
+
extern spinlock_t i8253_lock;
+extern struct clock_event_device *global_clock_event;
+
+/**
+ * pit_interrupt_hook - hook into timer tick
+ * @regs: standard registers from interrupt
+ *
+ * Call the global clock event handler.
+ **/
+static inline void pit_interrupt_hook(void)
+{
+ global_clock_event->event_handler(global_clock_event);
+}
+
#endif /* __ASM_I8253_H__ */
/* defines for inline arch setup functions */
+#include <linux/clockchips.h>
-#include <asm/apic.h>
#include <asm/i8259.h>
+#include <asm/i8253.h>
/**
* do_timer_interrupt_hook - hook into timer tick
- * @regs: standard registers from interrupt
*
- * Description:
- * This hook is called immediately after the timer interrupt is ack'd.
- * It's primary purpose is to allow architectures that don't possess
- * individual per CPU clocks (like the CPU APICs supply) to broadcast the
- * timer interrupt as a means of triggering reschedules etc.
+ * Call the pit clock event handler. see asm/i8253.h
**/
static inline void do_timer_interrupt_hook(void)
{
- do_timer(1);
-#ifndef CONFIG_SMP
- update_process_times(user_mode_vm(get_irq_regs()));
-#endif
-/*
- * In the SMP case we use the local APIC timer interrupt to do the
- * profiling, except when we simulate SMP mode on a uniprocessor
- * system, in that case we have to call the local interrupt handler.
- */
-#ifndef CONFIG_X86_LOCAL_APIC
- profile_tick(CPU_PROFILING);
-#else
- if (!using_apic_timer)
- smp_local_timer_interrupt();
-#endif
-}
-
-
-/* you can safely undefine this if you don't have the Neptune chipset */
-
-#define BUGGY_NEPTUN_TIMER
-
-/**
- * do_timer_overflow - process a detected timer overflow condition
- * @count: hardware timer interrupt count on overflow
- *
- * Description:
- * This call is invoked when the jiffies count has not incremented but
- * the hardware timer interrupt has. It means that a timer tick interrupt
- * came along while the previous one was pending, thus a tick was missed
- **/
-static inline int do_timer_overflow(int count)
-{
- int i;
-
- spin_lock(&i8259A_lock);
- /*
- * This is tricky when I/O APICs are used;
- * see do_timer_interrupt().
- */
- i = inb(0x20);
- spin_unlock(&i8259A_lock);
-
- /* assumption about timer being IRQ0 */
- if (i & 0x01) {
- /*
- * We cannot detect lost timer interrupts ...
- * well, that's why we call them lost, don't we? :)
- * [hmm, on the Pentium and Alpha we can ... sort of]
- */
- count -= LATCH;
- } else {
-#ifdef BUGGY_NEPTUN_TIMER
- /*
- * for the Neptun bug we know that the 'latch'
- * command doesn't latch the high and low value
- * of the counter atomically. Thus we have to
- * substract 256 from the counter
- * ... funny, isnt it? :)
- */
-
- count -= 256;
-#else
- printk("do_slow_gettimeoffset(): hardware timer problem?\n");
-#endif
- }
- return count;
+ pit_interrupt_hook();
}
/* defines for inline arch setup functions */
+#include <linux/clockchips.h>
+
#include <asm/voyager.h>
+#include <asm/i8253.h>
+/**
+ * do_timer_interrupt_hook - hook into timer tick
+ * @regs: standard registers from interrupt
+ *
+ * Call the pit clock event handler. see asm/i8253.h
+ **/
static inline void do_timer_interrupt_hook(void)
{
- do_timer(1);
-#ifndef CONFIG_SMP
- update_process_times(user_mode_vm(irq_regs));
-#endif
-
+ pit_interrupt_hook();
voyager_timer_interrupt();
}
-static inline int do_timer_overflow(int count)
-{
- /* can't read the ISR, just assume 1 tick
- overflow */
- if(count > LATCH || count < 0) {
- printk(KERN_ERR "VOYAGER PROBLEM: count is %d, latch is %d\n", count, LATCH);
- count = LATCH;
- }
- count -= LATCH;
-
- return count;
-}
extern int mpc_default_type;
extern unsigned long mp_lapic_addr;
extern int pic_mode;
-extern int using_apic_timer;
#ifdef CONFIG_ACPI
extern void mp_register_lapic (u8 id, u8 enabled);
projects / linux-2.6-omap-h63xx.git / commitdiff