[MIPS] Clockevent driver for BCM1480
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/sibyte/bcm1480/time.c b/arch/mips/sibyte/bcm1480/time.c
index 8519091..40d7126 100644
--- a/arch/mips/sibyte/bcm1480/time.c
+++ b/arch/mips/sibyte/bcm1480/time.c
@@ -25,6 +25,7 @@
* code to do general bookkeeping (e.g. update jiffies, run
* bottom halves, etc.)
*/
+#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
@@ -55,15 +56,12 @@
extern int bcm1480_steal_irq(int irq);
-void bcm1480_time_init(void)
+void __init plat_time_init(void)
{
- int cpu = smp_processor_id();
- int irq = K_BCM1480_INT_TIMER_0+cpu;
+ unsigned int cpu = smp_processor_id();
+ unsigned int irq = K_BCM1480_INT_TIMER_0 + cpu;
- /* Only have 4 general purpose timers */
- if (cpu > 3) {
- BUG();
- }
+ BUG_ON(cpu > 3); /* Only have 4 general purpose timers */
bcm1480_mask_irq(cpu, irq);
@@ -71,27 +69,83 @@
__raw_writeq(IMR_IP4_VAL, IOADDR(A_BCM1480_IMR_REGISTER(cpu, R_BCM1480_IMR_INTERRUPT_MAP_BASE_H)
+ (irq<<3)));
- /* the general purpose timer ticks at 1 Mhz independent of the rest of the system */
- /* Disable the timer and set up the count */
- __raw_writeq(0, IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
- __raw_writeq(
- BCM1480_HPT_VALUE/HZ
- , IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)));
-
- /* Set the timer running */
- __raw_writeq(M_SCD_TIMER_ENABLE|M_SCD_TIMER_MODE_CONTINUOUS,
- IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
-
bcm1480_unmask_irq(cpu, irq);
bcm1480_steal_irq(irq);
- /*
- * This interrupt is "special" in that it doesn't use the request_irq
- * way to hook the irq line. The timer interrupt is initialized early
- * enough to make this a major pain, and it's also firing enough to
- * warrant a bit of special case code. bcm1480_timer_interrupt is
- * called directly from irq_handler.S when IP[4] is set during an
- * interrupt
- */
+}
+
+/*
+ * The general purpose timer ticks at 1 Mhz independent if
+ * the rest of the system
+ */
+static void sibyte_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt)
+{
+ unsigned int cpu = smp_processor_id();
+ void __iomem *timer_cfg, *timer_init;
+
+ timer_cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+ timer_init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ __raw_writeq(0, timer_cfg);
+ __raw_writeq(BCM1480_HPT_VALUE / HZ - 1, timer_init);
+ __raw_writeq(M_SCD_TIMER_ENABLE | M_SCD_TIMER_MODE_CONTINUOUS,
+ timer_cfg);
+ break;
+
+ case CLOCK_EVT_MODE_ONESHOT:
+ /* Stop the timer until we actually program a shot */
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ __raw_writeq(0, timer_cfg);
+ break;
+
+ case CLOCK_EVT_MODE_UNUSED: /* shuddup gcc */
+ ;
+ }
+}
+
+struct clock_event_device sibyte_hpt_clockevent = {
+ .name = "bcm1480-counter",
+ .features = CLOCK_EVT_FEAT_PERIODIC,
+ .set_mode = sibyte_set_mode,
+ .shift = 32,
+ .irq = 0,
+};
+
+static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
+{
+ struct clock_event_device *cd = &sibyte_hpt_clockevent;
+ unsigned int cpu = smp_processor_id();
+
+ /* Reset the timer */
+ __raw_writeq(M_SCD_TIMER_ENABLE|M_SCD_TIMER_MODE_CONTINUOUS,
+ IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG)));
+ cd->event_handler(cd);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction sibyte_counter_irqaction = {
+ .handler = sibyte_counter_handler,
+ .flags = IRQF_DISABLED | IRQF_PERCPU,
+ .name = "timer",
+};
+
+/*
+ * This interrupt is "special" in that it doesn't use the request_irq
+ * way to hook the irq line. The timer interrupt is initialized early
+ * enough to make this a major pain, and it's also firing enough to
+ * warrant a bit of special case code. bcm1480_timer_interrupt is
+ * called directly from irq_handler.S when IP[4] is set during an
+ * interrupt
+ */
+static void __init sb1480_clockevent_init(void)
+{
+ unsigned int cpu = smp_processor_id();
+ unsigned int irq = K_BCM1480_INT_TIMER_0 + cpu;
+
+ setup_irq(irq, &sibyte_counter_irqaction);
}
void bcm1480_timer_interrupt(void)
@@ -118,4 +172,5 @@
{
clocksource_mips.read = bcm1480_hpt_read;
mips_hpt_frequency = BCM1480_HPT_VALUE;
+ sb1480_clockevent_init();
}