ARM: prima2: convert to common sched_clock() implementation

Prima2 has its own sched_clock() implementation, which gets in the
way of a single zImage. Moving to the common sched_clock framework
makes the code slightly cleaner (the mapping hack in sched_clock()
goes away...).

Acked-by: Barry Song <baohua.song@csr.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 7 insertions, 14 deletions

diff --git a/arch/arm/mach-prima2/timer.c b/arch/arm/mach-prima2/timer.c
index b7a6091ce791..0d024b1e916d 100644
--- a/arch/arm/mach-prima2/timer.c
+++ b/arch/arm/mach-prima2/timer.c
@@ -18,6 +18,7 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <mach/map.h>
+#include <asm/sched_clock.h>
 #include <asm/mach/time.h>
 
 #define SIRFSOC_TIMER_COUNTER_LO        0x0000
@@ -165,21 +166,9 @@ static struct irqaction sirfsoc_timer_irq = {
 };
 
 /* Overwrite weak default sched_clock with more precise one */
-unsigned long long notrace sched_clock(void)
+static u32 notrace sirfsoc_read_sched_clock(void)
 {
-        static int is_mapped;
-
-        /*
-         * sched_clock is called earlier than .init of sys_timer
-         * if we map timer memory in .init of sys_timer, system
-         * will panic due to illegal memory access
-         */
-        if (!is_mapped) {
-                sirfsoc_of_timer_map();
-                is_mapped = 1;
-        }
-
-        return sirfsoc_timer_read(NULL) * (NSEC_PER_SEC / CLOCK_TICK_RATE);
+        return (u32)(sirfsoc_timer_read(NULL) & 0xffffffff);
 }
 
 static void __init sirfsoc_clockevent_init(void)
@@ -210,6 +199,8 @@ static void __init sirfsoc_timer_init(void)
         BUG_ON(rate < CLOCK_TICK_RATE);
         BUG_ON(rate % CLOCK_TICK_RATE);
 
+        sirfsoc_of_timer_map();
+
         writel_relaxed(rate / CLOCK_TICK_RATE / 2 - 1, sirfsoc_timer_base + SIRFSOC_TIMER_DIV);
         writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);
         writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
@@ -217,6 +208,8 @@ static void __init sirfsoc_timer_init(void)
 
         BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE));
 
+        setup_sched_clock(sirfsoc_read_sched_clock, 32, CLOCK_TICK_RATE);
+
         BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));
 
         sirfsoc_clockevent_init();