diff options
| author | Nobuhiro Iwamatsu <iwamatsu@nigauri.org> | 2010-06-16 08:10:21 +0900 |
|---|---|---|
| committer | Nobuhiro Iwamatsu <iwamatsu@nigauri.org> | 2010-06-28 11:58:33 +0900 |
| commit | 61973afc5912c4c22d21f0412c824cbac1d3ee3f (patch) | |
| tree | fa8afc8108c2c00c350b49e5d61b68710875fc93 /arch/sh/lib/time.c | |
| parent | 8d1f63554b0371d3b30e481ac0aafa8253b515df (diff) | |
| download | u-boot-imx-61973afc5912c4c22d21f0412c824cbac1d3ee3f.zip u-boot-imx-61973afc5912c4c22d21f0412c824cbac1d3ee3f.tar.gz u-boot-imx-61973afc5912c4c22d21f0412c824cbac1d3ee3f.tar.bz2 | |
sh: Fix overflow problem in get_ticks
Signed-off-by: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
Diffstat (limited to 'arch/sh/lib/time.c')
| -rw-r--r-- | arch/sh/lib/time.c | 20 |
1 files changed, 18 insertions, 2 deletions
diff --git a/arch/sh/lib/time.c b/arch/sh/lib/time.c index 9a8f89a..bc1656f 100644 --- a/arch/sh/lib/time.c +++ b/arch/sh/lib/time.c @@ -2,7 +2,7 @@ * (C) Copyright 2009 * Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com> * - * (C) Copyright 2007-2008 + * (C) Copyright 2007-2010 * Nobobuhiro Iwamatsu <iwamatsu@nigauri.org> * * (C) Copyright 2003 @@ -36,6 +36,8 @@ #define TMU_MAX_COUNTER (~0UL) static ulong timer_freq; +static unsigned long last_tcnt; +static unsigned long long overflow_ticks; static inline unsigned long long tick_to_time(unsigned long long tick) { @@ -97,12 +99,26 @@ int timer_init (void) tmu_timer_stop(0); tmu_timer_start(0); + last_tcnt = 0; + overflow_ticks = 0; + return 0; } unsigned long long get_ticks (void) { - return 0 - readl(TCNT0); + unsigned long tcnt = 0 - readl(TCNT0); + unsigned long ticks; + + if (last_tcnt > tcnt) { /* overflow */ + overflow_ticks++; + ticks = (0xffffffff - last_tcnt) + tcnt; + } else { + ticks = tcnt; + } + last_tcnt = tcnt; + + return (overflow_ticks << 32) | tcnt; } void __udelay (unsigned long usec) |