clocksource: introduce CLOCK_MONOTONIC_RAW

[linux-2.6-omap-h63xx.git] / include / linux / clocksource.h

diff --git a/include/linux/clocksource.h b/include/linux/clocksource.h
index 35094479ca557012e043ea0def0fbf9b6df11e65..f88d32f8ff7c8a0d242763328c8e14f39445006d 100644 (file)
--- a/include/linux/clocksource.h
+++ b/include/linux/clocksource.h
@@ -45,7 +45,8 @@ struct clocksource;
  * @read:              returns a cycle value
  * @mask:              bitmask for two's complement
  *                     subtraction of non 64 bit counters
- * @mult:              cycle to nanosecond multiplier
+ * @mult:              cycle to nanosecond multiplier (adjusted by NTP)
+ * @mult_orig:         cycle to nanosecond multiplier (unadjusted by NTP)
  * @shift:             cycle to nanosecond divisor (power of two)
  * @flags:             flags describing special properties
  * @vread:             vsyscall based read
@@ -63,6 +64,7 @@ struct clocksource {
        cycle_t (*read)(void);
        cycle_t mask;
        u32 mult;
+       u32 mult_orig;
        u32 shift;
        unsigned long flags;
        cycle_t (*vread)(void);
@@ -77,6 +79,7 @@ struct clocksource {
        /* timekeeping specific data, ignore */
        cycle_t cycle_interval;
        u64     xtime_interval;
+       u32     raw_interval;
        /*
         * Second part is written at each timer interrupt
         * Keep it in a different cache line to dirty no
@@ -85,6 +88,7 @@ struct clocksource {
        cycle_t cycle_last ____cacheline_aligned_in_smp;
        u64 xtime_nsec;
        s64 error;
+       struct timespec raw_time;
 
 #ifdef CONFIG_CLOCKSOURCE_WATCHDOG
        /* Watchdog related data, used by the framework */
@@ -93,6 +97,8 @@ struct clocksource {
 #endif
 };
 
+extern struct clocksource *clock;      /* current clocksource */
+
 /*
  * Clock source flags bits::
  */
@@ -199,17 +205,19 @@ static inline void clocksource_calculate_interval(struct clocksource *c,
 {
        u64 tmp;
 
-       /* XXX - All of this could use a whole lot of optimization */
+       /* Do the ns -> cycle conversion first, using original mult */
        tmp = length_nsec;
        tmp <<= c->shift;
-       tmp += c->mult/2;
-       do_div(tmp, c->mult);
+       tmp += c->mult_orig/2;
+       do_div(tmp, c->mult_orig);
 
        c->cycle_interval = (cycle_t)tmp;
        if (c->cycle_interval == 0)
                c->cycle_interval = 1;
 
+       /* Go back from cycles -> shifted ns, this time use ntp adjused mult */
        c->xtime_interval = (u64)c->cycle_interval * c->mult;
+       c->raw_interval = ((u64)c->cycle_interval * c->mult_orig) >> c->shift;
 }