diff options
Diffstat (limited to 'arch/arm/plat-omap/counter_32k.c')
| -rw-r--r-- | arch/arm/plat-omap/counter_32k.c | 53 |
1 files changed, 33 insertions, 20 deletions
diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c index 2132c4f389e..61b4d705c26 100644 --- a/arch/arm/plat-omap/counter_32k.c +++ b/arch/arm/plat-omap/counter_32k.c @@ -18,18 +18,17 @@ #include <linux/err.h> #include <linux/io.h> #include <linux/clocksource.h> +#include <linux/sched_clock.h> #include <asm/mach/time.h> -#include <asm/sched_clock.h> -#include <plat/hardware.h> -#include <plat/common.h> -#include <plat/board.h> - -#include <plat/clock.h> +#include <plat/counter-32k.h> /* OMAP2_32KSYNCNT_CR_OFF: offset of 32ksync counter register */ -#define OMAP2_32KSYNCNT_CR_OFF 0x10 +#define OMAP2_32KSYNCNT_REV_OFF 0x0 +#define OMAP2_32KSYNCNT_REV_SCHEME (0x3 << 30) +#define OMAP2_32KSYNCNT_CR_OFF_LOW 0x10 +#define OMAP2_32KSYNCNT_CR_OFF_HIGH 0x30 /* * 32KHz clocksource ... always available, on pretty most chips except @@ -39,9 +38,9 @@ */ static void __iomem *sync32k_cnt_reg; -static u32 notrace omap_32k_read_sched_clock(void) +static u64 notrace omap_32k_read_sched_clock(void) { - return sync32k_cnt_reg ? __raw_readl(sync32k_cnt_reg) : 0; + return sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0; } /** @@ -52,22 +51,29 @@ static u32 notrace omap_32k_read_sched_clock(void) * nsecs and adds to a monotonically increasing timespec. */ static struct timespec persistent_ts; -static cycles_t cycles, last_cycles; +static cycles_t cycles; static unsigned int persistent_mult, persistent_shift; +static DEFINE_SPINLOCK(read_persistent_clock_lock); + static void omap_read_persistent_clock(struct timespec *ts) { unsigned long long nsecs; - cycles_t delta; - struct timespec *tsp = &persistent_ts; + cycles_t last_cycles; + unsigned long flags; + + spin_lock_irqsave(&read_persistent_clock_lock, flags); last_cycles = cycles; - cycles = sync32k_cnt_reg ? __raw_readl(sync32k_cnt_reg) : 0; - delta = cycles - last_cycles; + cycles = sync32k_cnt_reg ? readl_relaxed(sync32k_cnt_reg) : 0; + + nsecs = clocksource_cyc2ns(cycles - last_cycles, + persistent_mult, persistent_shift); + + timespec_add_ns(&persistent_ts, nsecs); - nsecs = clocksource_cyc2ns(delta, persistent_mult, persistent_shift); + *ts = persistent_ts; - timespec_add_ns(tsp, nsecs); - *ts = *tsp; + spin_unlock_irqrestore(&read_persistent_clock_lock, flags); } /** @@ -84,9 +90,16 @@ int __init omap_init_clocksource_32k(void __iomem *vbase) int ret; /* - * 32k sync Counter register offset is at 0x10 + * 32k sync Counter IP register offsets vary between the + * highlander version and the legacy ones. + * The 'SCHEME' bits(30-31) of the revision register is used + * to identify the version. */ - sync32k_cnt_reg = vbase + OMAP2_32KSYNCNT_CR_OFF; + if (readl_relaxed(vbase + OMAP2_32KSYNCNT_REV_OFF) & + OMAP2_32KSYNCNT_REV_SCHEME) + sync32k_cnt_reg = vbase + OMAP2_32KSYNCNT_CR_OFF_HIGH; + else + sync32k_cnt_reg = vbase + OMAP2_32KSYNCNT_CR_OFF_LOW; /* * 120000 rough estimate from the calculations in @@ -102,7 +115,7 @@ int __init omap_init_clocksource_32k(void __iomem *vbase) return ret; } - setup_sched_clock(omap_32k_read_sched_clock, 32, 32768); + sched_clock_register(omap_32k_read_sched_clock, 32, 32768); register_persistent_clock(NULL, omap_read_persistent_clock); pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n"); |