[MIPS] Clockevent driver for BCM1250

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 160 insertions, 21 deletions

diff --git a/arch/mips/sibyte/sb1250/time.c b/arch/mips/sibyte/sb1250/time.c
index eb177075e9c0..38199ad8fc54 100644
--- a/arch/mips/sibyte/sb1250/time.c
+++ b/arch/mips/sibyte/sb1250/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>
@@ -71,16 +72,158 @@ void __init sb1250_hpt_setup(void)
         }
 }
 
+/*
+ * 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((V_SCD_TIMER_FREQ / 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;
 
-void sb1250_time_init(void)
+        case CLOCK_EVT_MODE_UNUSED:     /* shuddup gcc */
+                ;
+        }
+}
+
+static int
+sibyte_next_event(unsigned long delta, struct clock_event_device *evt)
 {
-        int cpu = smp_processor_id();
-        int irq = K_INT_TIMER_0+cpu;
+        unsigned int cpu = smp_processor_id();
+        void __iomem *timer_cfg, *timer_init;
 
-        /* Only have 4 general purpose timers, and we use last one as hpt */
-        if (cpu > 2) {
-                BUG();
+        timer_cfg = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+        timer_init = IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_CFG));
+
+        __raw_writeq(0, timer_cfg);
+        __raw_writeq(delta, timer_init);
+        __raw_writeq(M_SCD_TIMER_ENABLE, timer_cfg);
+
+        return 0;
+}
+
+struct clock_event_device sibyte_hpt_clockevent = {
+        .name           = "sb1250-counter",
+        .features       = CLOCK_EVT_FEAT_PERIODIC,
+        .set_mode       = sibyte_set_mode,
+        .set_next_event = sibyte_next_event,
+        .shift          = 32,
+        .irq            = 0,
+};
+
+static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
+{
+        struct clock_event_device *cd = &sibyte_hpt_clockevent;
+
+        cd->event_handler(cd);
+
+        return IRQ_HANDLED;
+}
+
+static struct irqaction sibyte_irqaction = {
+        .handler        = sibyte_counter_handler,
+        .flags          = IRQF_DISABLED | IRQF_PERCPU,
+        .name           = "timer",
+};
+
+/*
+ * 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((V_SCD_TIMER_FREQ / 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 */
+                ;
         }
+}
+
+static int
+sibyte_next_event(unsigned long delta, 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));
+
+        __raw_writeq(0, timer_cfg);
+        __raw_writeq(delta, timer_init);
+        __raw_writeq(M_SCD_TIMER_ENABLE, timer_cfg);
+
+        return 0;
+}
+
+struct clock_event_device sibyte_hpt_clockevent = {
+        .name           = "sb1250-counter",
+        .features       = CLOCK_EVT_FEAT_PERIODIC,
+        .set_mode       = sibyte_set_mode,
+        .set_next_event = sibyte_next_event,
+        .shift          = 32,
+        .irq            = 0,
+};
+
+static irqreturn_t sibyte_counter_handler(int irq, void *dev_id)
+{
+        struct clock_event_device *cd = &sibyte_hpt_clockevent;
+
+        cd->event_handler(cd);
+
+        return IRQ_HANDLED;
+}
+
+static struct irqaction sibyte_irqaction = {
+        .handler        = sibyte_counter_handler,
+        .flags          = IRQF_DISABLED | IRQF_PERCPU,
+        .name           = "timer",
+};
+
+static void __init sb1250_clockevent_init(void)
+{
+        struct clock_event_device *cd = &sibyte_hpt_clockevent;
+        unsigned int cpu = smp_processor_id();
+        int irq = K_INT_TIMER_0 + cpu;
+
+        /* Only have 4 general purpose timers, and we use last one as hpt */
+        BUG_ON(cpu > 2);
 
         sb1250_mask_irq(cpu, irq);
 
@@ -88,24 +231,11 @@ void sb1250_time_init(void)
         __raw_writeq(IMR_IP4_VAL,
                      IOADDR(A_IMR_REGISTER(cpu, R_IMR_INTERRUPT_MAP_BASE) +
                             (irq << 3)));
-
-        /* the general purpose timer ticks at 1 Mhz independent if 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)));
-#ifdef CONFIG_SIMULATION
-        __raw_writeq((50000 / HZ) - 1,
-                     IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)));
-#else
-        __raw_writeq((V_SCD_TIMER_FREQ / HZ) - 1,
-                     IOADDR(A_SCD_TIMER_REGISTER(cpu, R_SCD_TIMER_INIT)));
-#endif
-
-        /* 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)));
+        cd->cpumask = cpumask_of_cpu(0);
 
         sb1250_unmask_irq(cpu, irq);
         sb1250_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
@@ -114,6 +244,15 @@ void sb1250_time_init(void)
          * called directly from irq_handler.S when IP[4] is set during an
          * interrupt
          */
+        setup_irq(irq, &sibyte_irqaction);
+
+        clockevents_register_device(cd);
+}
+
+void __init plat_time_init(void)
+{
+        sb1250_clocksource_init();
+        sb1250_clockevent_init();
 }
 
 /*