From: gregory.clement@free-electrons•com (Gregory CLEMENT)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH] clocksource: armada-370-xp: Enable timer divider only when needed
Date: Wed, 27 Nov 2013 15:34:41 +0100 [thread overview]
Message-ID: <52960301.8050202@free-electrons.com> (raw)
In-Reply-To: <1385562701-18976-1-git-send-email-ezequiel.garcia@free-electrons.com>
Hi Ezequiel,
On 27/11/2013 15:31, Ezequiel Garcia wrote:
> The current code sets the timer divider bits always. However, when
> the 25 MHz timer is enabled, this is not needed and has no effect.
> As this causes some confusion, rework the code so the divider is
> set only when needed, i.e. when the 25 MHz timer is not in use.
>
> Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons•com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons•com>
Thanks,
Gregory
> ---
> drivers/clocksource/time-armada-370-xp.c | 18 +++++++++---------
> 1 file changed, 9 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/clocksource/time-armada-370-xp.c b/drivers/clocksource/time-armada-370-xp.c
> index 4e7f680..ee8691b 100644
> --- a/drivers/clocksource/time-armada-370-xp.c
> +++ b/drivers/clocksource/time-armada-370-xp.c
> @@ -76,6 +76,7 @@
> static void __iomem *timer_base, *local_base;
> static unsigned int timer_clk;
> static bool timer25Mhz = true;
> +static u32 enable_mask;
>
> /*
> * Number of timer ticks per jiffy.
> @@ -121,8 +122,7 @@ armada_370_xp_clkevt_next_event(unsigned long delta,
> /*
> * Enable the timer.
> */
> - local_timer_ctrl_clrset(TIMER0_RELOAD_EN,
> - TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT));
> + local_timer_ctrl_clrset(TIMER0_RELOAD_EN, enable_mask);
> return 0;
> }
>
> @@ -141,9 +141,7 @@ armada_370_xp_clkevt_mode(enum clock_event_mode mode,
> /*
> * Enable timer.
> */
> - local_timer_ctrl_clrset(0, TIMER0_RELOAD_EN |
> - TIMER0_EN |
> - TIMER0_DIV(TIMER_DIVIDER_SHIFT));
> + local_timer_ctrl_clrset(0, TIMER0_RELOAD_EN | enable_mask);
> } else {
> /*
> * Disable timer.
> @@ -240,10 +238,13 @@ static void __init armada_370_xp_timer_common_init(struct device_node *np)
> WARN_ON(!timer_base);
> local_base = of_iomap(np, 1);
>
> - if (timer25Mhz)
> + if (timer25Mhz) {
> set = TIMER0_25MHZ;
> - else
> + enable_mask = TIMER0_EN;
> + } else {
> clr = TIMER0_25MHZ;
> + enable_mask = TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT);
> + }
> timer_ctrl_clrset(clr, set);
> local_timer_ctrl_clrset(clr, set);
>
> @@ -262,8 +263,7 @@ static void __init armada_370_xp_timer_common_init(struct device_node *np)
> writel(0xffffffff, timer_base + TIMER0_VAL_OFF);
> writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF);
>
> - timer_ctrl_clrset(0, TIMER0_EN | TIMER0_RELOAD_EN |
> - TIMER0_DIV(TIMER_DIVIDER_SHIFT));
> + timer_ctrl_clrset(0, TIMER0_RELOAD_EN | enable_mask);
>
> /*
> * Set scale and timer for sched_clock.
>
--
Gregory Clement, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com
prev parent reply other threads:[~2013-11-27 14:34 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-27 14:31 [PATCH] clocksource: armada-370-xp: Enable timer divider only when needed Ezequiel Garcia
2013-11-27 14:34 ` Gregory CLEMENT [this message]
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