From 8dfafdde88eb3e71d5569846396ae67a91017232 Mon Sep 17 00:00:00 2001 From: Rob Herring Date: Fri, 4 Oct 2013 10:22:41 -0500 Subject: Introduce common timer functions Many platforms duplicate pretty much the same timer code yet they all have a 32-bit freerunning counter register. Create a common implementation that minimally requires 2 or 3 defines to add timer support: CONFIG_SYS_TIMER_RATE - Clock rate of the timer counter CONFIG_SYS_TIMER_COUNTER - Address of 32-bit counter CONFIG_SYS_TIMER_COUNTS_DOWN - Define if counter counts down All functions are weak or ifdef'ed so they can still be overriden by any platform. Signed-off-by: Rob Herring --- lib/time.c | 73 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) (limited to 'lib/time.c') diff --git a/lib/time.c b/lib/time.c index 6514835df7..8361ddd69b 100644 --- a/lib/time.c +++ b/lib/time.c @@ -7,6 +7,8 @@ #include #include +#include +#include #if CONFIG_SYS_HZ != 1000 #warning "CONFIG_SYS_HZ must be 1000 and should not be defined by platforms" @@ -16,6 +18,77 @@ # define CONFIG_WD_PERIOD (10 * 1000 * 1000) /* 10 seconds default*/ #endif +DECLARE_GLOBAL_DATA_PTR; + +#ifdef CONFIG_SYS_TIMER_RATE +ulong notrace get_tbclk(void) +{ + return CONFIG_SYS_TIMER_RATE; +} +#endif + +#ifdef CONFIG_SYS_TIMER_COUNTER +unsigned long notrace timer_read_counter(void) +{ +#ifdef CONFIG_SYS_TIMER_COUNTS_DOWN + return ~readl(CONFIG_SYS_TIMER_COUNTER); +#else + return readl(CONFIG_SYS_TIMER_COUNTER); +#endif +} +#else +extern unsigned long timer_read_counter(void); +#endif + +unsigned long long __weak notrace get_ticks(void) +{ + unsigned long now = timer_read_counter(); + + /* increment tbu if tbl has rolled over */ + if (now < gd->timebase_l) + gd->timebase_h++; + gd->timebase_l = now; + return ((unsigned long long)gd->timebase_h << 32) | gd->timebase_l; +} + +static unsigned long long notrace tick_to_time(unsigned long long tick) +{ + unsigned int div = get_tbclk(); + + tick *= CONFIG_SYS_HZ; + do_div(tick, div); + return tick; +} + +ulong __weak get_timer(ulong base) +{ + return tick_to_time(get_ticks()) - base; +} + +unsigned long __weak notrace timer_get_us(void) +{ + return tick_to_time(get_ticks() * 1000); +} +static unsigned long long usec_to_tick(unsigned long usec) +{ + unsigned long long tick = usec * get_tbclk(); + usec *= get_tbclk(); + do_div(tick, 1000000); + return tick; +} + +void __weak __udelay(unsigned long usec) +{ + unsigned long long tmp; + ulong tmo; + + tmo = usec_to_tick(usec); + tmp = get_ticks() + tmo; /* get current timestamp */ + + while (get_ticks() < tmp) /* loop till event */ + /*NOP*/; +} + /* ------------------------------------------------------------------------- */ void udelay(unsigned long usec) -- cgit v1.2.1