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 <knut.wohlrab@de.bosch.com>
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Acked-by: Stefano Babic <sbabic@denx.de>
This commit is contained in:
Knut Wohlrab 2013-03-04 04:16:02 +00:00 committed by Stefano Babic
parent 40f1daa0b7
commit 982a3c410e

View File

@ -48,9 +48,6 @@ static struct mxc_gpt *cur_gpt = (struct mxc_gpt *)GPT1_BASE_ADDR;
DECLARE_GLOBAL_DATA_PTR; 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) static inline unsigned long long tick_to_time(unsigned long long tick)
{ {
tick *= CONFIG_SYS_HZ; 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 timer_init(void)
{ {
int i; int i;
ulong val;
/* setup GP Timer 1 */ /* setup GP Timer 1 */
__raw_writel(GPTCR_SWR, &cur_gpt->control); __raw_writel(GPTCR_SWR, &cur_gpt->control);
@ -85,9 +81,8 @@ int timer_init(void)
i = __raw_readl(&cur_gpt->control); i = __raw_readl(&cur_gpt->control);
__raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control); __raw_writel(i | GPTCR_CLKSOURCE_32 | GPTCR_TEN, &cur_gpt->control);
val = __raw_readl(&cur_gpt->counter); gd->arch.tbl = __raw_readl(&cur_gpt->counter);
lastinc = val / (MXC_CLK32 / CONFIG_SYS_HZ); gd->arch.tbu = 0;
timestamp = 0;
return 0; return 0;
} }
@ -96,18 +91,11 @@ unsigned long long get_ticks(void)
{ {
ulong now = __raw_readl(&cur_gpt->counter); /* current tick value */ ulong now = __raw_readl(&cur_gpt->counter); /* current tick value */
if (now >= lastinc) { /* increment tbu if tbl has rolled over */
/* if (now < gd->arch.tbl)
* normal mode (non roll) gd->arch.tbu++;
* move stamp forward with absolut diff ticks gd->arch.tbl = now;
*/ return (((unsigned long long)gd->arch.tbu) << 32) | gd->arch.tbl;
timestamp += (now - lastinc);
} else {
/* we have rollover of incrementer */
timestamp += (0xFFFFFFFF - lastinc) + now;
}
lastinc = now;
return timestamp;
} }
ulong get_timer_masked(void) ulong get_timer_masked(void)