diff options
Diffstat (limited to 'arch/arm64/lib/delay.c')
| -rw-r--r-- | arch/arm64/lib/delay.c | 23 |
1 files changed, 19 insertions, 4 deletions
diff --git a/arch/arm64/lib/delay.c b/arch/arm64/lib/delay.c index dad4ec9bbfd1..e48ac402e7be 100644 --- a/arch/arm64/lib/delay.c +++ b/arch/arm64/lib/delay.c @@ -24,10 +24,28 @@ #include <linux/module.h> #include <linux/timex.h> +#include <clocksource/arm_arch_timer.h> + +#define USECS_TO_CYCLES(time_usecs) \ + xloops_to_cycles((time_usecs) * 0x10C7UL) + +static inline unsigned long xloops_to_cycles(unsigned long xloops) +{ + return (xloops * loops_per_jiffy * HZ) >> 32; +} + void __delay(unsigned long cycles) { cycles_t start = get_cycles(); + if (arch_timer_evtstrm_available()) { + const cycles_t timer_evt_period = + USECS_TO_CYCLES(ARCH_TIMER_EVT_STREAM_PERIOD_US); + + while ((get_cycles() - start + timer_evt_period) < cycles) + wfe(); + } + while ((get_cycles() - start) < cycles) cpu_relax(); } @@ -35,10 +53,7 @@ EXPORT_SYMBOL(__delay); inline void __const_udelay(unsigned long xloops) { - unsigned long loops; - - loops = xloops * loops_per_jiffy * HZ; - __delay(loops >> 32); + __delay(xloops_to_cycles(xloops)); } EXPORT_SYMBOL(__const_udelay); |