From 9a4914ce0dff47b53df9ffbf9f48120b86ccb4a3 Mon Sep 17 00:00:00 2001 From: Russell King Date: Sat, 11 Mar 2017 17:42:34 +0000 Subject: 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 Signed-off-by: Daniel Lezcano --- drivers/clocksource/time-orion.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) (limited to 'drivers') diff --git a/drivers/clocksource/time-orion.c b/drivers/clocksource/time-orion.c index c4818a5..7eb2ab0 100644 --- a/drivers/clocksource/time-orion.c +++ b/drivers/clocksource/time-orion.c @@ -15,6 +15,7 @@ #include #include #include +#include #include #include #include @@ -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); -- cgit v1.1