^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Port on Texas Instruments TMS320C6x architecture
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Copyright (C) 2004, 2009, 2010, 2011 Texas Instruments Incorporated
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/clocksource.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/sched.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/param.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #include <linux/mm.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #include <linux/interrupt.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #include <linux/timex.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #include <linux/profile.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #include <asm/special_insns.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #include <asm/timer64.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) static u32 sched_clock_multiplier;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) #define SCHED_CLOCK_SHIFT 16
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) static u64 tsc_read(struct clocksource *cs)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) return get_cycles();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) static struct clocksource clocksource_tsc = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) .name = "timestamp",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) .rating = 300,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) .read = tsc_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) .mask = CLOCKSOURCE_MASK(64),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) .flags = CLOCK_SOURCE_IS_CONTINUOUS,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) * scheduler clock - returns current time in nanoseconds.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) u64 sched_clock(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) u64 tsc = get_cycles();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) return (tsc * sched_clock_multiplier) >> SCHED_CLOCK_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) void __init time_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) u64 tmp = (u64)NSEC_PER_SEC << SCHED_CLOCK_SHIFT;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) do_div(tmp, c6x_core_freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) sched_clock_multiplier = tmp;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) clocksource_register_hz(&clocksource_tsc, c6x_core_freq);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) /* write anything into TSCL to enable counting */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) set_creg(TSCL, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) /* probe for timer64 event timer */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) timer64_init();
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) }