+/*
+ * Clockevent device: interrupts every 1/HZ (== pit_cycles * MCK/16)
+ */
+static void
+pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
+{
+ unsigned long flags;
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ /* update clocksource counter, then enable the IRQ */
+ raw_local_irq_save(flags);
+ pit_cnt += pit_cycle * PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
+ at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
+ | AT91_PIT_PITIEN);
+ raw_local_irq_restore(flags);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ BUG();
+ /* FALLTHROUGH */
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+ /* disable irq, leaving the clocksource active */
+ at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
+ break;
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ }