diff options
| -rw-r--r-- | chip/ish/hwtimer.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/chip/ish/hwtimer.c b/chip/ish/hwtimer.c index 4b6faa96f8..276ef1b5db 100644 --- a/chip/ish/hwtimer.c +++ b/chip/ish/hwtimer.c @@ -44,6 +44,12 @@ static inline uint64_t scale_us2ticks(uint64_t us) return us * CLOCK_FACTOR; } +static inline uint32_t scale_us2ticks_32(uint32_t us) +{ + /* no optimization for ISH3 */ + return us * CLOCK_FACTOR; +} + static inline uint64_t scale_ticks2us(uint64_t ticks) { return ticks / CLOCK_FACTOR; @@ -58,6 +64,7 @@ static inline void wait_while_settling(uint32_t mask) #define CLOCK_SCALE_BITS 15 BUILD_ASSERT(BIT(CLOCK_SCALE_BITS) == ISH_HPET_CLK_FREQ); +/* Slow version, for 64-bit precision */ static inline uint64_t scale_us2ticks(uint64_t us) { /* ticks = us * ISH_HPET_CLK_FREQ / SECOND */ @@ -65,6 +72,16 @@ static inline uint64_t scale_us2ticks(uint64_t us) return (us << CLOCK_SCALE_BITS) / SECOND; } +/* Fast version, for 32-bit precision */ +static inline uint32_t scale_us2ticks_32(uint32_t us) +{ + /* + * GCC optimizes this shift/divide into multiplication by a + * magic number + */ + return (us << CLOCK_SCALE_BITS) / SECOND; +} + static inline uint64_t scale_ticks2us(uint64_t ticks) { return (ticks * SECOND) >> CLOCK_SCALE_BITS; @@ -139,7 +156,7 @@ void __hw_clock_event_set(uint32_t deadline) * every 10 seconds. */ wait_while_settling(HPET_T1_CMP_SETTLING); - HPET_TIMER_COMP(1) = current_ticks + scale_us2ticks(remaining_us); + HPET_TIMER_COMP(1) = current_ticks + scale_us2ticks_32(remaining_us); /* * Update 'last_deadline' and add calibrate delta due to HPET timer |