powerpc/time: Use clockevents_register_device(), fixing an issue with large decrementer

We currently cap the decrementer clockevent at 4 seconds, even on systems
with large decrementer support. Fix this by converting the code to use
clockevents_register_device() which calculates the upper bound based on
the max_delta passed in.

Signed-off-by: Anton Blanchard <anton@ozlabs.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 3 insertions, 14 deletions

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index 70f145e02487..6a1f0a084ca3 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -984,10 +984,10 @@ static void register_decrementer_clockevent(int cpu)
         *dec = decrementer_clockevent;
         dec->cpumask = cpumask_of(cpu);
 
+        clockevents_config_and_register(dec, ppc_tb_freq, 2, decrementer_max);
+
         printk_once(KERN_DEBUG "clockevent: %s mult[%x] shift[%d] cpu[%d]\n",
                     dec->name, dec->mult, dec->shift, cpu);
-
-        clockevents_register_device(dec);
 }
 
 static void enable_large_decrementer(void)
@@ -1035,18 +1035,7 @@ static void __init set_decrementer_max(void)
 
 static void __init init_decrementer_clockevent(void)
 {
-        int cpu = smp_processor_id();
-
-        clockevents_calc_mult_shift(&decrementer_clockevent, ppc_tb_freq, 4);
-
-        decrementer_clockevent.max_delta_ns =
-                clockevent_delta2ns(decrementer_max, &decrementer_clockevent);
-        decrementer_clockevent.max_delta_ticks = decrementer_max;
-        decrementer_clockevent.min_delta_ns =
-                clockevent_delta2ns(2, &decrementer_clockevent);
-        decrementer_clockevent.min_delta_ticks = 2;
-
-        register_decrementer_clockevent(cpu);
+        register_decrementer_clockevent(smp_processor_id());
 }
 
 void secondary_cpu_time_init(void)