diff options
Diffstat (limited to 'arch/arm/mach-at91rm9200/time.c')
| -rw-r--r-- | arch/arm/mach-at91rm9200/time.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/arch/arm/mach-at91rm9200/time.c b/arch/arm/mach-at91rm9200/time.c index 7ffcf443b99f..36798a8d532a 100644 --- a/arch/arm/mach-at91rm9200/time.c +++ b/arch/arm/mach-at91rm9200/time.c | |||
| @@ -31,6 +31,8 @@ | |||
| 31 | #include <asm/irq.h> | 31 | #include <asm/irq.h> |
| 32 | #include <asm/mach/time.h> | 32 | #include <asm/mach/time.h> |
| 33 | 33 | ||
| 34 | static unsigned long last_crtr; | ||
| 35 | |||
| 34 | /* | 36 | /* |
| 35 | * The ST_CRTR is updated asynchronously to the master clock. It is therefore | 37 | * The ST_CRTR is updated asynchronously to the master clock. It is therefore |
| 36 | * necessary to read it twice (with the same value) to ensure accuracy. | 38 | * necessary to read it twice (with the same value) to ensure accuracy. |
| @@ -56,7 +58,7 @@ static unsigned long at91rm9200_gettimeoffset(void) | |||
| 56 | { | 58 | { |
| 57 | unsigned long elapsed; | 59 | unsigned long elapsed; |
| 58 | 60 | ||
| 59 | elapsed = (read_CRTR() - at91_sys_read(AT91_ST_RTAR)) & AT91_ST_ALMV; | 61 | elapsed = (read_CRTR() - last_crtr) & AT91_ST_ALMV; |
| 60 | 62 | ||
| 61 | return (unsigned long)(elapsed * (tick_nsec / 1000)) / LATCH; | 63 | return (unsigned long)(elapsed * (tick_nsec / 1000)) / LATCH; |
| 62 | } | 64 | } |
| @@ -66,15 +68,12 @@ static unsigned long at91rm9200_gettimeoffset(void) | |||
| 66 | */ | 68 | */ |
| 67 | static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) | 69 | static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) |
| 68 | { | 70 | { |
| 69 | unsigned long rtar; | ||
| 70 | |||
| 71 | if (at91_sys_read(AT91_ST_SR) & AT91_ST_PITS) { /* This is a shared interrupt */ | 71 | if (at91_sys_read(AT91_ST_SR) & AT91_ST_PITS) { /* This is a shared interrupt */ |
| 72 | write_seqlock(&xtime_lock); | 72 | write_seqlock(&xtime_lock); |
| 73 | 73 | ||
| 74 | while (((read_CRTR() - at91_sys_read(AT91_ST_RTAR)) & AT91_ST_ALMV) >= LATCH) { | 74 | while (((read_CRTR() - last_crtr) & AT91_ST_ALMV) >= LATCH) { |
| 75 | timer_tick(regs); | 75 | timer_tick(regs); |
| 76 | rtar = (at91_sys_read(AT91_ST_RTAR) + LATCH) & AT91_ST_ALMV; | 76 | last_crtr = (last_crtr + LATCH) & AT91_ST_ALMV; |
| 77 | at91_sys_write(AT91_ST_RTAR, rtar); | ||
| 78 | } | 77 | } |
| 79 | 78 | ||
| 80 | write_sequnlock(&xtime_lock); | 79 | write_sequnlock(&xtime_lock); |
| @@ -87,7 +86,7 @@ static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id, struct pt_r | |||
| 87 | 86 | ||
| 88 | static struct irqaction at91rm9200_timer_irq = { | 87 | static struct irqaction at91rm9200_timer_irq = { |
| 89 | .name = "at91_tick", | 88 | .name = "at91_tick", |
| 90 | .flags = SA_SHIRQ | SA_INTERRUPT, | 89 | .flags = SA_SHIRQ | SA_INTERRUPT | SA_TIMER, |
| 91 | .handler = at91rm9200_timer_interrupt | 90 | .handler = at91rm9200_timer_interrupt |
| 92 | }; | 91 | }; |
| 93 | 92 | ||
