[PARISC] Add new function to start local Interval Timer, start_cpu_it…

…imer()

I couldn't find where the itimer was getting started for slave CPUs.
CPU 0 (master) itimer was started in time_init() (arch/parisc/kernel/time.c).
start_cpu_itimer() code was striped from time_init().
Slaves now start their itimer in smp_cpu_init().

This is a first step towards making gettimeoffset() work for SMP.
Next step will be to determine the CR16 (cycle counter)
offsets for each CPU relative to the master (CPU 0).

Signed-off-by: Grant Grundler <[email protected]>
Signed-off-by: Kyle McMartin <[email protected]>

arch/parisc/kernel/smp.c

@@ -430,8 +430,9 @@ smp_do_timer(struct pt_regs *regs)
 static void __init
 smp_cpu_init(int cpunum)
 {
-	extern int init_per_cpu(int);  /* arch/parisc/kernel/setup.c */
+	extern int init_per_cpu(int);  /* arch/parisc/kernel/processor.c */
 	extern void init_IRQ(void);    /* arch/parisc/kernel/irq.c */
+	extern void start_cpu_itimer(void); /* arch/parisc/kernel/time.c */
 
 	/* Set modes and Enable floating point coprocessor */
 	(void) init_per_cpu(cpunum);
@@ -457,6 +458,7 @@ smp_cpu_init(int cpunum)
 	enter_lazy_tlb(&init_mm, current);
 
 	init_IRQ();   /* make sure no IRQ's are enabled or pending */
+	start_cpu_itimer();
 }
 
 

arch/parisc/kernel/time.c

@@ -223,22 +223,24 @@ unsigned long long sched_clock(void)
 }
 
 
+void __init start_cpu_itimer(void)
+{
+	unsigned int cpu = smp_processor_id();
+	unsigned long next_tick = mfctl(16) + clocktick;
+
+	mtctl(next_tick, 16);		/* kick off Interval Timer (CR16) */
+
+	cpu_data[cpu].it_value = next_tick;
+}
+
 void __init time_init(void)
 {
-	unsigned long next_tick;
 	static struct pdc_tod tod_data;
 
 	clocktick = (100 * PAGE0->mem_10msec) / HZ;
 	halftick = clocktick / 2;
 
-	/* Setup clock interrupt timing */
-
-	next_tick = mfctl(16);
-	next_tick += clocktick;
-	cpu_data[smp_processor_id()].it_value = next_tick;
-
-	/* kick off Itimer (CR16) */
-	mtctl(next_tick, 16);
+	start_cpu_itimer();	/* get CPU 0 started */
 
 	if(pdc_tod_read(&tod_data) == 0) {
 		write_seqlock_irq(&xtime_lock);