diff options
| author | Russell King <rmk+kernel@armlinux.org.uk> | 2017-03-11 18:42:34 +0100 |
|---|---|---|
| committer | Daniel Lezcano <daniel.lezcano@linaro.org> | 2017-04-07 16:23:03 +0200 |
| commit | 9a4914ce0dff47b53df9ffbf9f48120b86ccb4a3 (patch) | |
| tree | 5629c50430e4ae90e435dc19f7a7701f8054c4d1 /drivers/clocksource | |
| parent | clocksource/drivers/orion: Read clock rate once (diff) | |
| download | linux-9a4914ce0dff47b53df9ffbf9f48120b86ccb4a3.tar.xz linux-9a4914ce0dff47b53df9ffbf9f48120b86ccb4a3.zip | |
clocksource/drivers/orion: Add delay_timer implementation
Add an implementation for the ARM delay timer, which is used for
udelay(). This provides less CPU dependent and more accurate delays -
the CPU loop on Marvell Dove appears to calibrate to around 6% too
short.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Diffstat (limited to 'drivers/clocksource')
| -rw-r--r-- | drivers/clocksource/time-orion.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/clocksource/time-orion.c b/drivers/clocksource/time-orion.c index c4818a5dc8e5..7eb2ab0bd114 100644 --- a/drivers/clocksource/time-orion.c +++ b/drivers/clocksource/time-orion.c @@ -15,6 +15,7 @@ #include <linux/bitops.h> #include <linux/clk.h> #include <linux/clockchips.h> +#include <linux/delay.h> #include <linux/interrupt.h> #include <linux/of_address.h> #include <linux/of_irq.h> @@ -36,6 +37,21 @@ static void __iomem *timer_base; +static unsigned long notrace orion_read_timer(void) +{ + return ~readl(timer_base + TIMER0_VAL); +} + +static struct delay_timer orion_delay_timer = { + .read_current_timer = orion_read_timer, +}; + +static void orion_delay_timer_init(unsigned long rate) +{ + orion_delay_timer.freq = rate; + register_current_timer_delay(&orion_delay_timer); +} + /* * Free-running clocksource handling. */ @@ -168,6 +184,9 @@ static int __init orion_timer_init(struct device_node *np) clockevents_config_and_register(&orion_clkevt, rate, ORION_ONESHOT_MIN, ORION_ONESHOT_MAX); + + orion_delay_timer_init(rate); + return 0; } CLOCKSOURCE_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init); |