linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] [v5] clocksource/drivers/npcm: fix GENMASK and timer operation
@ 2019-07-29 17:03 Avi Fishman
  2019-08-21 10:11 ` Daniel Lezcano
  0 siblings, 1 reply; 3+ messages in thread
From: Avi Fishman @ 2019-07-29 17:03 UTC (permalink / raw)
  To: tmaimon77, tali.perry1, venture, yuenn, benjaminfair,
	daniel.lezcano, tglx, avifishman70
  Cc: openbmc, linux-kernel

NPCM7XX_Tx_OPER GENMASK bits where wrong,
Since NPCM7XX_REG_TICR0 register reset value of those bits was 0,
it did not cause an issue.
in npcm7xx_timer_oneshot() the original NPCM7XX_REG_TCSR0 register was
read again after masking it with ~NPCM7XX_Tx_OPER so the masking didn't
take effect.

npcm7xx_timer_periodic() was not wrong but it wrote to NPCM7XX_REG_TICR0
in a middle of read modify write to NPCM7XX_REG_TCSR0 which is
confusing.
npcm7xx_timer_oneshot() did wrong calculation

Signed-off-by: Avi Fishman <avifishman70@gmail.com>
---
 drivers/clocksource/timer-npcm7xx.c | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/clocksource/timer-npcm7xx.c b/drivers/clocksource/timer-npcm7xx.c
index 8a30da7f083b..9780ffd8010e 100644
--- a/drivers/clocksource/timer-npcm7xx.c
+++ b/drivers/clocksource/timer-npcm7xx.c
@@ -32,7 +32,7 @@
 #define NPCM7XX_Tx_INTEN		BIT(29)
 #define NPCM7XX_Tx_COUNTEN		BIT(30)
 #define NPCM7XX_Tx_ONESHOT		0x0
-#define NPCM7XX_Tx_OPER			GENMASK(27, 3)
+#define NPCM7XX_Tx_OPER			GENMASK(28, 27)
 #define NPCM7XX_Tx_MIN_PRESCALE		0x1
 #define NPCM7XX_Tx_TDR_MASK_BITS	24
 #define NPCM7XX_Tx_MAX_CNT		0xFFFFFF
@@ -84,8 +84,6 @@ static int npcm7xx_timer_oneshot(struct clock_event_device *evt)
 
 	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
 	val &= ~NPCM7XX_Tx_OPER;
-
-	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
 	val |= NPCM7XX_START_ONESHOT_Tx;
 	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
 
@@ -97,12 +95,11 @@ static int npcm7xx_timer_periodic(struct clock_event_device *evt)
 	struct timer_of *to = to_timer_of(evt);
 	u32 val;
 
+	writel(timer_of_period(to), timer_of_base(to) + NPCM7XX_REG_TICR0);
+
 	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
 	val &= ~NPCM7XX_Tx_OPER;
-
-	writel(timer_of_period(to), timer_of_base(to) + NPCM7XX_REG_TICR0);
 	val |= NPCM7XX_START_PERIODIC_Tx;
-
 	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
 
 	return 0;
-- 
2.18.0


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2019-08-21 10:44 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-07-29 17:03 [PATCH] [v5] clocksource/drivers/npcm: fix GENMASK and timer operation Avi Fishman
2019-08-21 10:11 ` Daniel Lezcano
2019-08-21 10:42   ` Avi Fishman

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).