diff options
Diffstat (limited to 'arch/c6x/kernel/time.c')
-rw-r--r-- | arch/c6x/kernel/time.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/c6x/kernel/time.c b/arch/c6x/kernel/time.c new file mode 100644 index 000000000000..4c9f136165f7 --- /dev/null +++ b/arch/c6x/kernel/time.c @@ -0,0 +1,65 @@ +/* + * Port on Texas Instruments TMS320C6x architecture + * + * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated + * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/kernel.h> +#include <linux/clocksource.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/param.h> +#include <linux/string.h> +#include <linux/mm.h> +#include <linux/interrupt.h> +#include <linux/timex.h> +#include <linux/profile.h> + +#include <asm/timer64.h> + +static u32 sched_clock_multiplier; +#define SCHED_CLOCK_SHIFT 16 + +static cycle_t tsc_read(struct clocksource *cs) +{ + return get_cycles(); +} + +static struct clocksource clocksource_tsc = { + .name = "timestamp", + .rating = 300, + .read = tsc_read, + .mask = CLOCKSOURCE_MASK(64), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +/* + * scheduler clock - returns current time in nanoseconds. + */ +u64 sched_clock(void) +{ + u64 tsc = get_cycles(); + + return (tsc * sched_clock_multiplier) >> SCHED_CLOCK_SHIFT; +} + +void time_init(void) +{ + u64 tmp = (u64)NSEC_PER_SEC << SCHED_CLOCK_SHIFT; + + do_div(tmp, c6x_core_freq); + sched_clock_multiplier = tmp; + + clocksource_register_hz(&clocksource_tsc, c6x_core_freq); + + /* write anything into TSCL to enable counting */ + set_creg(TSCL, 0); + + /* probe for timer64 event timer */ + timer64_init(); +} |