From 982a3c410e21f2f7e5fee22c7fd788fc7ef7fdf9 Mon Sep 17 00:00:00 2001 From: Knut Wohlrab Date: Mon, 4 Mar 2013 04:16:02 +0000 Subject: [PATCH] imx-common: timer: fix 32-bit overflow The i.MX6 common timer uses the 32-bit variable tbl (time base lower) to record the overflow of the 32-bit counter. I.e. if the counter overflows, the variable tbl does overflow, too. To capture this overflow, use the variable tbu (time base upper), too. Return the combined value of tbl and tbu. lastinc is unused then, remove it. Signed-off-by: Knut Wohlrab Signed-off-by: Dirk Behme Acked-by: Stefano Babic --- arch/arm/imx-common/timer.c | 26 +++++++------------------- 1 file changed, 7 insertions(+), 19 deletions(-) diff --git a/arch/arm/imx-common/timer.c b/arch/arm/imx-common/timer.c index ab37d64..1dbc413 100644 --- a/arch/arm/imx-common/timer.c +++ b/arch/arm/imx-common/timer.c @@ -48,9 +48,6 @@ static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR; DECLARE_GLOBAL_DATA_PTR; -#define timestamp (gd->arch.tbl) -#define lastinc (gd->arch.lastinc) - static inline unsigned long long tick_to_time(unsigned long long tick) { tick *= CONFIG_SYS_HZ; @@ -70,7 +67,6 @@ static inline unsigned long long us_to_tick(unsigned long long usec) int timer_init(void) { int i; - ulong val; /* setup GP Timer 1 */ __raw_writel(GPTCR_SWR, &cur_gpt->control); @@ -85,9 +81,8 @@ int timer_init(void) i = __raw_readl(&cur_gpt->control); __raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control); - val = __raw_readl(&cur_gpt->counter); - lastinc = val / (MXC_CLK32 / CONFIG_SYS_HZ); - timestamp = 0; + gd->arch.tbl = __raw_readl(&cur_gpt->counter); + gd->arch.tbu = 0; return 0; } @@ -96,18 +91,11 @@ unsigned long long get_ticks(void) { ulong now = __raw_readl(&cur_gpt->counter); /* current tick value */ - if (now >= lastinc) { - /* - * normal mode (non roll) - * move stamp forward with absolut diff ticks - */ - timestamp += (now - lastinc); - } else { - /* we have rollover of incrementer */ - timestamp += (0xFFFFFFFF - lastinc) + now; - } - lastinc = now; - return timestamp; + /* increment tbu if tbl has rolled over */ + if (now < gd->arch.tbl) + gd->arch.tbu++; + gd->arch.tbl = now; + return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl; } ulong get_timer_masked(void) -- 2.7.4