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Diffstat (limited to '')
| -rw-r--r-- | arch/arm/mach-mmp/time.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/arch/arm/mach-mmp/time.c b/arch/arm/mach-mmp/time.c index 96ad1db0b..edd280e75 100644 --- a/arch/arm/mach-mmp/time.c +++ b/arch/arm/mach-mmp/time.c @@ -52,18 +52,21 @@ static void __iomem *mmp_timer_base = TIMERS_VIRT_BASE; /* - * FIXME: the timer needs some delay to stablize the counter capture + * Read the timer through the CVWR register. Delay is required after requesting + * a read. The CR register cannot be directly read due to metastability issues + * documented in the PXA168 software manual. */ static inline uint32_t timer_read(void) { - int delay = 100; + uint32_t val; + int delay = 3; __raw_writel(1, mmp_timer_base + TMR_CVWR(1)); while (delay--) - cpu_relax(); + val = __raw_readl(mmp_timer_base + TMR_CVWR(1)); - return __raw_readl(mmp_timer_base + TMR_CVWR(1)); + return val; } static u64 notrace mmp_read_sched_clock(void) |