Merge branch 'next/cross-platform' of git://git.kernel.org/pub/scm/linux/kernel/git...

[pandora-kernel.git] / drivers / clocksource / i8253.c

diff --git a/drivers/clocksource/i8253.c b/drivers/clocksource/i8253.c
index 225c176..27c49e6 100644 (file)
--- a/drivers/clocksource/i8253.c
+++ b/drivers/clocksource/i8253.c
@@ -1,14 +1,25 @@
 /*
  * i8253 PIT clocksource
  */
-#include <linux/clocksource.h>
+#include <linux/clockchips.h>
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/spinlock.h>
 #include <linux/timex.h>
+#include <linux/module.h>
+#include <linux/i8253.h>
+#include <linux/smp.h>
 
-#include <asm/i8253.h>
+/*
+ * Protects access to I/O ports
+ *
+ * 0040-0043 : timer0, i8253 / i8254
+ * 0061-0061 : NMI Control Register which contains two speaker control bits.
+ */
+DEFINE_RAW_SPINLOCK(i8253_lock);
+EXPORT_SYMBOL(i8253_lock);
 
+#ifdef CONFIG_CLKSRC_I8253
 /*
  * Since the PIT overflows every tick, its not very useful
  * to just read by itself. So use jiffies to emulate a free
@@ -37,15 +48,15 @@ static cycle_t i8253_read(struct clocksource *cs)
         * count), it cannot be newer.
         */
        jifs = jiffies;
-       outb_pit(0x00, PIT_MODE);       /* latch the count ASAP */
-       count = inb_pit(PIT_CH0);       /* read the latched count */
-       count |= inb_pit(PIT_CH0) << 8;
+       outb_p(0x00, PIT_MODE); /* latch the count ASAP */
+       count = inb_p(PIT_CH0); /* read the latched count */
+       count |= inb_p(PIT_CH0) << 8;
 
        /* VIA686a test code... reset the latch if count > max + 1 */
        if (count > LATCH) {
-               outb_pit(0x34, PIT_MODE);
-               outb_pit(PIT_LATCH & 0xff, PIT_CH0);
-               outb_pit(PIT_LATCH >> 8, PIT_CH0);
+               outb_p(0x34, PIT_MODE);
+               outb_p(PIT_LATCH & 0xff, PIT_CH0);
+               outb_p(PIT_LATCH >> 8, PIT_CH0);
                count = PIT_LATCH - 1;
        }
 
@@ -86,3 +97,90 @@ int __init clocksource_i8253_init(void)
 {
        return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
 }
+#endif
+
+#ifdef CONFIG_CLKEVT_I8253
+/*
+ * 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)
+{
+       raw_spin_lock(&i8253_lock);
+
+       switch (mode) {
+       case CLOCK_EVT_MODE_PERIODIC:
+               /* binary, mode 2, LSB/MSB, ch 0 */
+               outb_p(0x34, PIT_MODE);
+               outb_p(LATCH & 0xff , PIT_CH0); /* LSB */
+               outb_p(LATCH >> 8 , PIT_CH0);           /* MSB */
+               break;
+
+       case CLOCK_EVT_MODE_SHUTDOWN:
+       case CLOCK_EVT_MODE_UNUSED:
+               if (evt->mode == CLOCK_EVT_MODE_PERIODIC ||
+                   evt->mode == CLOCK_EVT_MODE_ONESHOT) {
+                       outb_p(0x30, PIT_MODE);
+                       outb_p(0, PIT_CH0);
+                       outb_p(0, PIT_CH0);
+               }
+               break;
+
+       case CLOCK_EVT_MODE_ONESHOT:
+               /* One shot setup */
+               outb_p(0x38, PIT_MODE);
+               break;
+
+       case CLOCK_EVT_MODE_RESUME:
+               /* Nothing to do here */
+               break;
+       }
+       raw_spin_unlock(&i8253_lock);
+}
+
+/*
+ * 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)
+{
+       raw_spin_lock(&i8253_lock);
+       outb_p(delta & 0xff , PIT_CH0); /* LSB */
+       outb_p(delta >> 8 , PIT_CH0);           /* MSB */
+       raw_spin_unlock(&i8253_lock);
+
+       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.
+ */
+struct clock_event_device i8253_clockevent = {
+       .name           = "pit",
+       .features       = CLOCK_EVT_FEAT_PERIODIC,
+       .set_mode       = init_pit_timer,
+       .set_next_event = pit_next_event,
+};
+
+/*
+ * 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 clockevent_i8253_init(bool oneshot)
+{
+       if (oneshot)
+               i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
+       /*
+        * Start pit with the boot cpu mask. x86 might make it global
+        * when it is used as broadcast device later.
+        */
+       i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
+
+       clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
+                                       0xF, 0x7FFF);
+}
+#endif