summaryrefslogtreecommitdiffstats
path: root/arch/arm/plat-omap/counter_32k.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/plat-omap/counter_32k.c')
-rw-r--r--arch/arm/plat-omap/counter_32k.c37
1 files changed, 27 insertions, 10 deletions
diff --git a/arch/arm/plat-omap/counter_32k.c b/arch/arm/plat-omap/counter_32k.c
index 2132c4f..2bc51fb 100644
--- a/arch/arm/plat-omap/counter_32k.c
+++ b/arch/arm/plat-omap/counter_32k.c
@@ -29,7 +29,10 @@
#include <plat/clock.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
@@ -52,22 +55,29 @@ 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;
- nsecs = clocksource_cyc2ns(delta, persistent_mult, persistent_shift);
+ nsecs = clocksource_cyc2ns(cycles - last_cycles,
+ persistent_mult, persistent_shift);
+
+ timespec_add_ns(&persistent_ts, nsecs);
+
+ *ts = persistent_ts;
- timespec_add_ns(tsp, nsecs);
- *ts = *tsp;
+ spin_unlock_irqrestore(&read_persistent_clock_lock, flags);
}
/**
@@ -84,9 +94,16 @@ 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 (__raw_readl(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