diff options
| author | Linus Walleij <linus.walleij@stericsson.com> | 2010-06-01 09:26:49 +0200 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2010-06-16 23:29:31 +0200 |
| commit | 2917947a673763be5f94313a59e5f28ee01b3d9d (patch) | |
| tree | 7cf356130bf1cf94c9ca26494ae5fd92a14073b3 /arch/arm | |
| parent | ARM: 6177/1: nomadik-gpio: fix "ignoring return value" warning (diff) | |
| download | linux-2917947a673763be5f94313a59e5f28ee01b3d9d.tar.xz linux-2917947a673763be5f94313a59e5f28ee01b3d9d.zip | |
ARM: 6153/1: nomadik MTU to use dynamic shift and mult assignment
This removes the hard-coded shift values for the MTU timer, since
the different platforms using this has very different running
frequencies doing this dynamically is a better idea. Also take
this opportunity to make a more through shutdown of the MTU
clockevent when requested.
Acked-by: Alessandro Rubini <rubini@unipv.it>
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/plat-nomadik/include/plat/mtu.h | 6 | ||||
| -rw-r--r-- | arch/arm/plat-nomadik/timer.c | 14 |
2 files changed, 16 insertions, 4 deletions
diff --git a/arch/arm/plat-nomadik/include/plat/mtu.h b/arch/arm/plat-nomadik/include/plat/mtu.h index 42c907258b14..65704a3d4241 100644 --- a/arch/arm/plat-nomadik/include/plat/mtu.h +++ b/arch/arm/plat-nomadik/include/plat/mtu.h @@ -1,6 +1,12 @@ #ifndef __PLAT_MTU_H #define __PLAT_MTU_H +/* + * Guaranteed runtime conversion range in seconds for + * the clocksource and clockevent. + */ +#define MTU_MIN_RANGE 4 + /* should be set by the platform code */ extern void __iomem *mtu_base; diff --git a/arch/arm/plat-nomadik/timer.c b/arch/arm/plat-nomadik/timer.c index 08aaa4a7f65f..ea3ca86c5283 100644 --- a/arch/arm/plat-nomadik/timer.c +++ b/arch/arm/plat-nomadik/timer.c @@ -42,7 +42,6 @@ static struct clocksource nmdk_clksrc = { .rating = 200, .read = nmdk_read_timer_dummy, .mask = CLOCKSOURCE_MASK(32), - .shift = 20, .flags = CLOCK_SOURCE_IS_CONTINUOUS, }; @@ -82,6 +81,12 @@ static void nmdk_clkevt_mode(enum clock_event_mode mode, case CLOCK_EVT_MODE_UNUSED: /* disable irq */ writel(0, mtu_base + MTU_IMSC); + /* disable timer */ + cr = readl(mtu_base + MTU_CR(1)); + cr &= ~MTU_CRn_ENA; + writel(cr, mtu_base + MTU_CR(1)); + /* load some high default value */ + writel(0xffffffff, mtu_base + MTU_LR(1)); break; case CLOCK_EVT_MODE_RESUME: break; @@ -98,7 +103,6 @@ static int nmdk_clkevt_next(unsigned long evt, struct clock_event_device *ev) static struct clock_event_device nmdk_clkevt = { .name = "mtu_1", .features = CLOCK_EVT_FEAT_ONESHOT, - .shift = 32, .rating = 200, .set_mode = nmdk_clkevt_mode, .set_next_event = nmdk_clkevt_next, @@ -151,6 +155,7 @@ void __init nmdk_timer_init(void) } else { cr |= MTU_CRn_PRESCALE_1; } + clocksource_calc_mult_shift(&nmdk_clksrc, rate, MTU_MIN_RANGE); /* Timer 0 is the free running clocksource */ writel(cr, mtu_base + MTU_CR(0)); @@ -158,7 +163,6 @@ void __init nmdk_timer_init(void) writel(0, mtu_base + MTU_BGLR(0)); writel(cr | MTU_CRn_ENA, mtu_base + MTU_CR(0)); - nmdk_clksrc.mult = clocksource_hz2mult(rate, nmdk_clksrc.shift); /* Now the scheduling clock is ready */ nmdk_clksrc.read = nmdk_read_timer; @@ -175,8 +179,10 @@ void __init nmdk_timer_init(void) } else { cr |= MTU_CRn_PRESCALE_1; } + clockevents_calc_mult_shift(&nmdk_clkevt, rate, MTU_MIN_RANGE); + writel(cr | MTU_CRn_ONESHOT, mtu_base + MTU_CR(1)); /* off, currently */ - nmdk_clkevt.mult = div_sc(rate, NSEC_PER_SEC, nmdk_clkevt.shift); + nmdk_clkevt.max_delta_ns = clockevent_delta2ns(0xffffffff, &nmdk_clkevt); nmdk_clkevt.min_delta_ns = |