diff options
Diffstat (limited to 'arch/arc/kernel/time.c')
| -rw-r--r-- | arch/arc/kernel/time.c | 38 |
1 files changed, 2 insertions, 36 deletions
diff --git a/arch/arc/kernel/time.c b/arch/arc/kernel/time.c index 0ce0e6f76eb0..f13f72807aa5 100644 --- a/arch/arc/kernel/time.c +++ b/arch/arc/kernel/time.c @@ -76,7 +76,7 @@ static cycle_t arc_counter_read(struct clocksource *cs) __asm__ __volatile( " .extCoreRegister tsch, 58, r, cannot_shortcut \n" " rtsc %0, 0 \n" - " mov %1, tsch \n" /* TSCH is extn core reg 58 */ + " mov %1, 0 \n" : "=r" (stamp.low), "=r" (stamp.high)); arch_local_irq_restore(flags); @@ -88,7 +88,7 @@ static struct clocksource arc_counter = { .name = "ARC RTSC", .rating = 300, .read = arc_counter_read, - .mask = CLOCKSOURCE_MASK(64), + .mask = CLOCKSOURCE_MASK(32), .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; @@ -263,37 +263,3 @@ void __init time_init(void) if (machine_desc->init_time) machine_desc->init_time(); } - -#ifdef CONFIG_ARC_HAS_RTSC -/* - * sched_clock math assist - * ns = cycles * (ns_per_sec / cpu_freq_hz) - * ns = cycles * (10^6 / cpu_freq_khz) - * ns = cycles * (10^6 * 2^SF / cpu_freq_khz) / 2^SF - * ns = cycles * cyc2ns_scale >> SF - */ -#define CYC2NS_SF 10 /* 2^10, carefully chosen */ -#define CYC2NS_SCALE ((1000000 << CYC2NS_SF) / (arc_get_core_freq() / 1000)) - -static unsigned long long cycles2ns(unsigned long long cyc) -{ - return (cyc * CYC2NS_SCALE ) >> CYC2NS_SF; -} - -/* - * Scheduler clock - a monotonically increasing clock in nanosec units. - * It's return value must NOT wrap around. - * - * - Since 32bit TIMER1 will overflow almost immediately (53sec @ 80MHz), it - * can't be used directly. - * - Using getrawmonotonic (TIMER1 based, but with state for last + current - * snapshots), is no-good either because of seqlock deadlock possibilities - * - So only with native 64bit timer we do this, otherwise fallback to generic - * jiffies based version - which despite not being fine grained gaurantees - * the monotonically increasing semantics. - */ -unsigned long long sched_clock(void) -{ - return cycles2ns(arc_counter_read(NULL)); -} -#endif |