openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

ARM: OMAP: timer32k: fix tick count calculation when reprogramming 

Reprogramming takes places before putting the CPU into idle mode if
the dynamic tick option is enabled. The timer is then set to expire
at the next pending timer event. Because some time has already passed
since the last reported jiffy we have to wait less than the time
specified in jiffies.

Also make sure we don't set a load value of 0 whose outcome is
unspecified according to the TRM.

Signed-off-by: Imre Deak <imre.deak@solidboot.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
This commit is contained in:
Imre Deak 2006-09-25 12:41:21 +03:00 committed by Tony Lindgren
parent ae78dcf79a
commit df51a84d93
1 changed files with 11 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arch/arm/plat-omap/timer32k.c
View File

@ -105,6 +105,8 @@ static inline unsigned long omap_32k_timer_read(int reg)
static inline void omap_32k_timer_start(unsigned long load_val)
{
if (!load_val)
load_val = 1;
omap_32k_timer_write(load_val, OMAP1_32K_TIMER_TVR);
omap_32k_timer_write(0x0f, OMAP1_32K_TIMER_CR);
}
@ -230,7 +232,15 @@ static irqreturn_t omap_32k_timer_interrupt(int irq, void *dev_id,
*/
void omap_32k_timer_reprogram(unsigned long next_tick)
{
omap_32k_timer_start(JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1);
unsigned long ticks = JIFFIES_TO_HW_TICKS(next_tick, 32768) + 1;
unsigned long now = omap_32k_sync_timer_read();
unsigned long idled = now - omap_32k_last_tick;
if (idled + 1 < ticks)
ticks -= idled;
else
ticks = 1;
omap_32k_timer_start(ticks);
}
static struct irqaction omap_32k_timer_irq;