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Diffstat (limited to 'arch/blackfin/kernel/time-ts.c')
-rw-r--r--arch/blackfin/kernel/time-ts.c47
1 files changed, 27 insertions, 20 deletions
diff --git a/arch/blackfin/kernel/time-ts.c b/arch/blackfin/kernel/time-ts.c
index 359cfb1815c..17c38c5b5b2 100644
--- a/arch/blackfin/kernel/time-ts.c
+++ b/arch/blackfin/kernel/time-ts.c
@@ -22,8 +22,6 @@
#include <asm/time.h>
#include <asm/gptimers.h>
-#if defined(CONFIG_CYCLES_CLOCKSOURCE)
-
/* Accelerators for sched_clock()
* convert from cycles(64bits) => nanoseconds (64bits)
* basic equation:
@@ -46,20 +44,11 @@
* -johnstul@us.ibm.com "math is hard, lets go shopping!"
*/
-static unsigned long cyc2ns_scale;
#define CYC2NS_SCALE_FACTOR 10 /* 2^10, carefully chosen */
-static inline void set_cyc2ns_scale(unsigned long cpu_khz)
-{
- cyc2ns_scale = (1000000 << CYC2NS_SCALE_FACTOR) / cpu_khz;
-}
-
-static inline unsigned long long cycles_2_ns(cycle_t cyc)
-{
- return (cyc * cyc2ns_scale) >> CYC2NS_SCALE_FACTOR;
-}
+#if defined(CONFIG_CYCLES_CLOCKSOURCE)
-static cycle_t bfin_read_cycles(struct clocksource *cs)
+static notrace cycle_t bfin_read_cycles(struct clocksource *cs)
{
return __bfin_cycles_off + (get_cycles() << __bfin_cycles_mod);
}
@@ -69,19 +58,18 @@ static struct clocksource bfin_cs_cycles = {
.rating = 400,
.read = bfin_read_cycles,
.mask = CLOCKSOURCE_MASK(64),
- .shift = 22,
+ .shift = CYC2NS_SCALE_FACTOR,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
-unsigned long long sched_clock(void)
+static inline unsigned long long bfin_cs_cycles_sched_clock(void)
{
- return cycles_2_ns(bfin_read_cycles(&bfin_cs_cycles));
+ return clocksource_cyc2ns(bfin_read_cycles(&bfin_cs_cycles),
+ bfin_cs_cycles.mult, bfin_cs_cycles.shift);
}
static int __init bfin_cs_cycles_init(void)
{
- set_cyc2ns_scale(get_cclk() / 1000);
-
bfin_cs_cycles.mult = \
clocksource_hz2mult(get_cclk(), bfin_cs_cycles.shift);
@@ -108,7 +96,7 @@ void __init setup_gptimer0(void)
enable_gptimers(TIMER0bit);
}
-static cycle_t bfin_read_gptimer0(void)
+static cycle_t bfin_read_gptimer0(struct clocksource *cs)
{
return bfin_read_TIMER0_COUNTER();
}
@@ -118,10 +106,16 @@ static struct clocksource bfin_cs_gptimer0 = {
.rating = 350,
.read = bfin_read_gptimer0,
.mask = CLOCKSOURCE_MASK(32),
- .shift = 22,
+ .shift = CYC2NS_SCALE_FACTOR,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
+static inline unsigned long long bfin_cs_gptimer0_sched_clock(void)
+{
+ return clocksource_cyc2ns(bfin_read_TIMER0_COUNTER(),
+ bfin_cs_gptimer0.mult, bfin_cs_gptimer0.shift);
+}
+
static int __init bfin_cs_gptimer0_init(void)
{
setup_gptimer0();
@@ -138,6 +132,19 @@ static int __init bfin_cs_gptimer0_init(void)
# define bfin_cs_gptimer0_init()
#endif
+
+#if defined(CONFIG_GPTMR0_CLOCKSOURCE) || defined(CONFIG_CYCLES_CLOCKSOURCE)
+/* prefer to use cycles since it has higher rating */
+notrace unsigned long long sched_clock(void)
+{
+#if defined(CONFIG_CYCLES_CLOCKSOURCE)
+ return bfin_cs_cycles_sched_clock();
+#else
+ return bfin_cs_gptimer0_sched_clock();
+#endif
+}
+#endif
+
#ifdef CONFIG_CORE_TIMER_IRQ_L1
__attribute__((l1_text))
#endif