diff options
Diffstat (limited to 'cpu')
| -rw-r--r-- | cpu/arm920t/ep93xx/timer.c | 31 |
1 files changed, 13 insertions, 18 deletions
diff --git a/cpu/arm920t/ep93xx/timer.c b/cpu/arm920t/ep93xx/timer.c index b1a01a05e9..31304b7f97 100644 --- a/cpu/arm920t/ep93xx/timer.c +++ b/cpu/arm920t/ep93xx/timer.c @@ -36,7 +36,7 @@ #define TIMER_CLKSEL (1 << 3) #define TIMER_ENABLE (1 << 7) -#define TIMER_FREQ 508469 +#define TIMER_FREQ 508469 /* ticks / second */ #define TIMER_MAX_VAL 0xFFFFFFFF static struct ep93xx_timer @@ -53,18 +53,10 @@ static inline unsigned long clk_to_systicks(unsigned long long clk_ticks) return (unsigned long)sys_ticks; } -static inline unsigned long usecs_to_ticks(unsigned long usecs) +static inline unsigned long long usecs_to_ticks(unsigned long usecs) { - unsigned long ticks; - - if (usecs >= 1000) { - ticks = usecs / 1000; - ticks *= TIMER_FREQ; - ticks /= 1000; - } else { - ticks = usecs * TIMER_FREQ; - ticks /= (1000 * 1000); - } + unsigned long long ticks = (unsigned long long)usecs * TIMER_FREQ; + do_div(ticks, 1000 * 1000); return ticks; } @@ -77,7 +69,7 @@ static inline unsigned long read_timer(void) } /* - * timer without interrupts + * Get the number of ticks (in CONFIG_SYS_HZ resolution) */ unsigned long long get_ticks(void) { @@ -91,12 +83,12 @@ unsigned long long get_ticks(void) timer.last_update = now; - return timer.ticks; + return clk_to_systicks(timer.ticks); } unsigned long get_timer_masked(void) { - return clk_to_systicks(get_ticks()); + return get_ticks(); } unsigned long get_timer(unsigned long base) @@ -117,10 +109,13 @@ void reset_timer(void) void __udelay(unsigned long usec) { - const unsigned long target = get_ticks() + usecs_to_ticks(usec); + /* read the timer and update timer.ticks */ + get_ticks(); + + const unsigned long long target = timer.ticks + usecs_to_ticks(usec); - while (get_ticks() < target) - /* noop */; + while (timer.ticks < target) + get_ticks(); } int timer_init(void) |