Messages in this thread | | | Subject | Re: [PATCH] [v2] clocksource/drivers/npcm: fix GENMASK and timer operation | From | Joe Perches <> | Date | Mon, 15 Jul 2019 08:25:01 -0700 |
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On Mon, 2019-07-15 at 18:19 +0300, Avi Fishman wrote: > clocksource/drivers/npcm: fix GENMASK and timer operation > > NPCM7XX_Tx_OPER GENMASK() changed from (27, 3) to (28, 27) > > 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.
You might mention how the original use of GENMASK(3, 27) was defective or correct without effect.
> 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; >
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