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clocksource: sh_cmt: One-off clockevent fix

PATCH New Magnus Damm 1 participant 2 messages Aug 2, 2010 – Aug 4, 2010

Subsystems (2)
SuperH Clocksource, clockevent drivers
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Magnus Damm

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#0 lore raw

PATCH 1/1 clocksource: sh_cmt: One-off clockevent fix

From: Magnus Damm <[email protected]>

Fix a one-off error in the clockevent part of the CMT driver. The match register should be programmed with the period minus one.

Many thanks to Eiraku-san for tracking down this issue.

Reported-by Hideki EIRAKU <[email protected]>
Signed-off-by Magnus Damm <[email protected]>

---

 drivers/clocksource/sh_cmt.c |    6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
drivers/clocksource/sh_cmt.c +3 -3
@@ -478,7 +478,7 @@ static void sh_cmt_clock_event_start(str
 	ced->min_delta_ns = clockevent_delta2ns(0x1f, ced);
 
 	if (periodic)
-		sh_cmt_set_next(p, (p->rate + HZ/2) / HZ);
+		sh_cmt_set_next(p, ((p->rate + HZ/2) / HZ) - 1);
 	else
 		sh_cmt_set_next(p, p->max_match_value);
 }

@@ -523,9 +523,9 @@ static int sh_cmt_clock_event_next(unsig
 
 	BUG_ON(ced->mode != CLOCK_EVT_MODE_ONESHOT);
 	if (likely(p->flags & FLAG_IRQCONTEXT))
-		p->next_match_value = delta;
+		p->next_match_value = delta - 1;
 	else
-		sh_cmt_set_next(p, delta);
+		sh_cmt_set_next(p, delta - 1);
 
 	return 0;
 }
author
#1 lore raw

PATCH 1/1 clocksource: sh_cmt: One-off clockevent fix V2

From: Magnus Damm <[email protected]>

Fix a one-off error in the CMT driver V2. The match register should be programmed with the period minus one.

Many thanks to Eiraku-san for tracking down this issue.

Signed-off-by Magnus Damm <[email protected]>

---

Changes since V1:
- the clocksource counter need to be adjusted as well

 drivers/clocksource/sh_cmt.c |   10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)
drivers/clocksource/sh_cmt.c +5 -5
@@ -308,7 +308,7 @@ static irqreturn_t sh_cmt_interrupt(int 
 	 * isr before we end up here.
 	 */
 	if (p->flags & FLAG_CLOCKSOURCE)
-		p->total_cycles += p->match_value;
+		p->total_cycles += p->match_value + 1;
 
 	if (!(p->flags & FLAG_REPROGRAM))
 		p->next_match_value = p->max_match_value;

@@ -403,7 +403,7 @@ static cycle_t sh_cmt_clocksource_read(s
 	raw = sh_cmt_get_counter(p, &has_wrapped);
 
 	if (unlikely(has_wrapped))
-		raw += p->match_value;
+		raw += p->match_value + 1;
 	spin_unlock_irqrestore(&p->lock, flags);
 
 	return value + raw;

@@ -478,7 +478,7 @@ static void sh_cmt_clock_event_start(str
 	ced->min_delta_ns = clockevent_delta2ns(0x1f, ced);
 
 	if (periodic)
-		sh_cmt_set_next(p, (p->rate + HZ/2) / HZ);
+		sh_cmt_set_next(p, ((p->rate + HZ/2) / HZ) - 1);
 	else
 		sh_cmt_set_next(p, p->max_match_value);
 }

@@ -523,9 +523,9 @@ static int sh_cmt_clock_event_next(unsig
 
 	BUG_ON(ced->mode != CLOCK_EVT_MODE_ONESHOT);
 	if (likely(p->flags & FLAG_IRQCONTEXT))
-		p->next_match_value = delta;
+		p->next_match_value = delta - 1;
 	else
-		sh_cmt_set_next(p, delta);
+		sh_cmt_set_next(p, delta - 1);
 
 	return 0;
 }