NSEC = 10^-9 */
#define FSEC_PER_NSEC 1000000L
+#define HPET_DEV_USED_BIT 2
+#define HPET_DEV_USED (1 << HPET_DEV_USED_BIT)
+#define HPET_DEV_VALID 0x8
+#define HPET_DEV_FSB_CAP 0x1000
+#define HPET_DEV_PERI_CAP 0x2000
+
+#define EVT_TO_HPET_DEV(evt) container_of(evt, struct hpet_dev, evt)
+
/*
* HPET address is set in acpi/boot.c, when an ACPI entry exists
*/
unsigned long hpet_address;
+unsigned long hpet_num_timers;
static void __iomem *hpet_virt_address;
struct hpet_dev {
char name[10];
};
+static struct hpet_dev *hpet_devs;
+
+static DEFINE_PER_CPU(struct hpet_dev *, cpu_hpet_dev);
+
unsigned long hpet_readl(unsigned long a)
{
return readl(hpet_virt_address + a);
Tn_INT_ROUTE_CNF_MASK) >> Tn_INT_ROUTE_CNF_SHIFT;
}
+ for (i = 0; i < nrtimers; i++) {
+ struct hpet_dev *hdev = &hpet_devs[i];
+
+ if (!(hdev->flags & HPET_DEV_VALID))
+ continue;
+
+ hd.hd_irq[hdev->num] = hdev->irq;
+ hpet_reserve_timer(&hd, hdev->num);
+ }
+
hpet_alloc(&hd);
}
printk(KERN_DEBUG "hpet clockevent registered\n");
}
+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)
{
break;
case CLOCK_EVT_MODE_RESUME:
- hpet_enable_legacy_int();
+ if (timer == 0) {
+ hpet_enable_legacy_int();
+ } else {
+ struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
+ hpet_setup_msi_irq(hdev->irq);
+ disable_irq(hdev->irq);
+ irq_set_affinity(hdev->irq, cpumask_of_cpu(hdev->cpu));
+ enable_irq(hdev->irq);
+ }
break;
}
}
/*
* HPET MSI Support
*/
-
+#ifdef CONFIG_PCI_MSI
void hpet_msi_unmask(unsigned int irq)
{
struct hpet_dev *hdev = get_irq_data(irq);
msg->address_hi = 0;
}
+static void hpet_msi_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
+ hpet_set_mode(mode, evt, hdev->num);
+}
+
+static int hpet_msi_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ struct hpet_dev *hdev = EVT_TO_HPET_DEV(evt);
+ return hpet_next_event(delta, evt, hdev->num);
+}
+
+static int hpet_setup_msi_irq(unsigned int irq)
+{
+ if (arch_setup_hpet_msi(irq)) {
+ destroy_irq(irq);
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int hpet_assign_irq(struct hpet_dev *dev)
+{
+ unsigned int irq;
+
+ irq = create_irq();
+ if (!irq)
+ return -EINVAL;
+
+ set_irq_data(irq, dev);
+
+ if (hpet_setup_msi_irq(irq))
+ return -EINVAL;
+
+ dev->irq = irq;
+ return 0;
+}
+
+static irqreturn_t hpet_interrupt_handler(int irq, void *data)
+{
+ struct hpet_dev *dev = (struct hpet_dev *)data;
+ struct clock_event_device *hevt = &dev->evt;
+
+ if (!hevt->event_handler) {
+ printk(KERN_INFO "Spurious HPET timer interrupt on HPET timer %d\n",
+ dev->num);
+ return IRQ_HANDLED;
+ }
+
+ hevt->event_handler(hevt);
+ return IRQ_HANDLED;
+}
+
+static int hpet_setup_irq(struct hpet_dev *dev)
+{
+
+ if (request_irq(dev->irq, hpet_interrupt_handler,
+ IRQF_SHARED|IRQF_NOBALANCING, dev->name, dev))
+ return -1;
+
+ disable_irq(dev->irq);
+ irq_set_affinity(dev->irq, cpumask_of_cpu(dev->cpu));
+ enable_irq(dev->irq);
+
+ return 0;
+}
+
+/* This should be called in specific @cpu */
+static void init_one_hpet_msi_clockevent(struct hpet_dev *hdev, int cpu)
+{
+ struct clock_event_device *evt = &hdev->evt;
+ uint64_t hpet_freq;
+
+ WARN_ON(cpu != smp_processor_id());
+ if (!(hdev->flags & HPET_DEV_VALID))
+ return;
+
+ if (hpet_setup_msi_irq(hdev->irq))
+ return;
+
+ hdev->cpu = cpu;
+ per_cpu(cpu_hpet_dev, cpu) = hdev;
+ evt->name = hdev->name;
+ hpet_setup_irq(hdev);
+ evt->irq = hdev->irq;
+
+ evt->rating = 110;
+ evt->features = CLOCK_EVT_FEAT_ONESHOT;
+ if (hdev->flags & HPET_DEV_PERI_CAP)
+ evt->features |= CLOCK_EVT_FEAT_PERIODIC;
+
+ evt->set_mode = hpet_msi_set_mode;
+ evt->set_next_event = hpet_msi_next_event;
+ evt->shift = 32;
+
+ /*
+ * 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);
+ evt->mult = div_sc((unsigned long) hpet_freq,
+ NSEC_PER_SEC, evt->shift);
+ /* Calculate the max delta */
+ evt->max_delta_ns = clockevent_delta2ns(0x7FFFFFFF, evt);
+ /* 5 usec minimum reprogramming delta. */
+ evt->min_delta_ns = 5000;
+
+ evt->cpumask = cpumask_of_cpu(hdev->cpu);
+ clockevents_register_device(evt);
+}
+
+#ifdef CONFIG_HPET
+/* Reserve at least one timer for userspace (/dev/hpet) */
+#define RESERVE_TIMERS 1
+#else
+#define RESERVE_TIMERS 0
+#endif
+void hpet_msi_capability_lookup(unsigned int start_timer)
+{
+ unsigned int id;
+ unsigned int num_timers;
+ unsigned int num_timers_used = 0;
+ int i;
+
+ id = hpet_readl(HPET_ID);
+
+ num_timers = ((id & HPET_ID_NUMBER) >> HPET_ID_NUMBER_SHIFT);
+ num_timers++; /* Value read out starts from 0 */
+
+ hpet_devs = kzalloc(sizeof(struct hpet_dev) * num_timers, GFP_KERNEL);
+ if (!hpet_devs)
+ return;
+
+ hpet_num_timers = num_timers;
+
+ for (i = start_timer; i < num_timers - RESERVE_TIMERS; i++) {
+ struct hpet_dev *hdev = &hpet_devs[num_timers_used];
+ unsigned long cfg = hpet_readl(HPET_Tn_CFG(i));
+
+ /* Only consider HPET timer with MSI support */
+ if (!(cfg & HPET_TN_FSB_CAP))
+ continue;
+
+ hdev->flags = 0;
+ if (cfg & HPET_TN_PERIODIC_CAP)
+ hdev->flags |= HPET_DEV_PERI_CAP;
+ hdev->num = i;
+
+ sprintf(hdev->name, "hpet%d", i);
+ if (hpet_assign_irq(hdev))
+ continue;
+
+ hdev->flags |= HPET_DEV_FSB_CAP;
+ hdev->flags |= HPET_DEV_VALID;
+ num_timers_used++;
+ if (num_timers_used == num_possible_cpus())
+ break;
+ }
+
+ printk(KERN_INFO "HPET: %d timers in total, %d timers will be used for per-cpu timer\n",
+ num_timers, num_timers_used);
+}
+
+static struct hpet_dev *hpet_get_unused_timer(void)
+{
+ int i;
+
+ if (!hpet_devs)
+ return NULL;
+
+ for (i = 0; i < hpet_num_timers; i++) {
+ struct hpet_dev *hdev = &hpet_devs[i];
+
+ if (!(hdev->flags & HPET_DEV_VALID))
+ continue;
+ if (test_and_set_bit(HPET_DEV_USED_BIT,
+ (unsigned long *)&hdev->flags))
+ continue;
+ return hdev;
+ }
+ return NULL;
+}
+
+struct hpet_work_struct {
+ struct delayed_work work;
+ struct completion complete;
+};
+
+static void hpet_work(struct work_struct *w)
+{
+ struct hpet_dev *hdev;
+ int cpu = smp_processor_id();
+ struct hpet_work_struct *hpet_work;
+
+ hpet_work = container_of(w, struct hpet_work_struct, work.work);
+
+ hdev = hpet_get_unused_timer();
+ if (hdev)
+ init_one_hpet_msi_clockevent(hdev, cpu);
+
+ complete(&hpet_work->complete);
+}
+
+static int hpet_cpuhp_notify(struct notifier_block *n,
+ unsigned long action, void *hcpu)
+{
+ unsigned long cpu = (unsigned long)hcpu;
+ struct hpet_work_struct work;
+ struct hpet_dev *hdev = per_cpu(cpu_hpet_dev, cpu);
+
+ switch (action & 0xf) {
+ case CPU_ONLINE:
+ INIT_DELAYED_WORK(&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);
+ break;
+ case CPU_DEAD:
+ if (hdev) {
+ free_irq(hdev->irq, hdev);
+ hdev->flags &= ~HPET_DEV_USED;
+ per_cpu(cpu_hpet_dev, cpu) = NULL;
+ }
+ break;
+ }
+ return NOTIFY_OK;
+}
+#else
+
+void hpet_msi_capability_lookup(unsigned int start_timer)
+{
+ return;
+}
+
+static int hpet_cpuhp_notify(struct notifier_block *n,
+ unsigned long action, void *hcpu)
+{
+ return NOTIFY_OK;
+}
+
+#endif
+
/*
* Clock source related code
*/
if (id & HPET_ID_LEGSUP) {
hpet_legacy_clockevent_register();
+ hpet_msi_capability_lookup(2);
return 1;
}
+ hpet_msi_capability_lookup(0);
return 0;
out_nohpet:
*/
static __init int hpet_late_init(void)
{
+ int cpu;
+
if (boot_hpet_disable)
return -ENODEV;
hpet_reserve_platform_timers(hpet_readl(HPET_ID));
+ for_each_online_cpu(cpu) {
+ hpet_cpuhp_notify(NULL, CPU_ONLINE, (void *)(long)cpu);
+ }
+
+ /* This notifier should be called after workqueue is ready */
+ hotcpu_notifier(hpet_cpuhp_notify, -20);
+
return 0;
}
fs_initcall(hpet_late_init);
projects / linux-2.6-omap-h63xx.git / commitdiff