1 files changed, 20 insertions, 1 deletions

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 92dc844299b6..36707dec94d7 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -54,6 +54,7 @@
 #include <linux/irq.h>
 #include <linux/delay.h>
 #include <linux/perf_event.h>
+#include <asm/trace.h>
 
 #include <asm/io.h>
 #include <asm/processor.h>
@@ -571,6 +572,8 @@ void timer_interrupt(struct pt_regs * regs)
         struct clock_event_device *evt = &decrementer->event;
         u64 now;
 
+        trace_timer_interrupt_entry(regs);
+
         /* Ensure a positive value is written to the decrementer, or else
          * some CPUs will continuue to take decrementer exceptions */
         set_dec(DECREMENTER_MAX);
@@ -590,6 +593,7 @@ void timer_interrupt(struct pt_regs * regs)
                 now = decrementer->next_tb - now;
                 if (now <= DECREMENTER_MAX)
                         set_dec((int)now);
+                trace_timer_interrupt_exit(regs);
                 return;
         }
         old_regs = set_irq_regs(regs);
@@ -620,6 +624,8 @@ void timer_interrupt(struct pt_regs * regs)
 
         irq_exit();
         set_irq_regs(old_regs);
+
+        trace_timer_interrupt_exit(regs);
 }
 
 void wakeup_decrementer(void)
@@ -777,7 +783,7 @@ int update_persistent_clock(struct timespec now)
         return ppc_md.set_rtc_time(&tm);
 }
 
-void read_persistent_clock(struct timespec *ts)
+static void __read_persistent_clock(struct timespec *ts)
 {
         struct rtc_time tm;
         static int first = 1;
@@ -800,10 +806,23 @@ void read_persistent_clock(struct timespec *ts)
                 return;
         }
         ppc_md.get_rtc_time(&tm);
+
         ts->tv_sec = mktime(tm.tm_year+1900, tm.tm_mon+1, tm.tm_mday,
                             tm.tm_hour, tm.tm_min, tm.tm_sec);
 }
 
+void read_persistent_clock(struct timespec *ts)
+{
+        __read_persistent_clock(ts);
+
+        /* Sanitize it in case real time clock is set below EPOCH */
+        if (ts->tv_sec < 0) {
+                ts->tv_sec = 0;
+                ts->tv_nsec = 0;
+        }
+                
+}
+
 /* clocksource code */
 static cycle_t rtc_read(struct clocksource *cs)
 {