From 92e0d143fdef1faa7560c93fb0d6cd6c61da88ee Mon Sep 17 00:00:00 2001 From: Anup Patel Date: Tue, 4 Dec 2018 15:59:52 +0530 Subject: [PATCH] clocksource/drivers/riscv_timer: Provide the sched_clock Currently, we don't have a sched_clock registered for RISC-V systems. This means Linux time keeping will use jiffies (running at HZ) as the default sched_clock. To avoid this, we explicity provide sched_clock using RISC-V rdtime instruction (similar to riscv_timer clocksource). Signed-off-by: Anup Patel Reviewed-by: Palmer Dabbelt Signed-off-by: Daniel Lezcano --- drivers/clocksource/Kconfig | 2 +- drivers/clocksource/riscv_timer.c | 9 +++++++++ 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index c57b156f49a2..a4ae339e0101 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -599,7 +599,7 @@ config ATCPIT100_TIMER config RISCV_TIMER bool "Timer for the RISC-V platform" - depends on RISCV + depends on GENERIC_SCHED_CLOCK && RISCV default y select TIMER_PROBE select TIMER_OF diff --git a/drivers/clocksource/riscv_timer.c b/drivers/clocksource/riscv_timer.c index 084e97dc10ed..431892200a08 100644 --- a/drivers/clocksource/riscv_timer.c +++ b/drivers/clocksource/riscv_timer.c @@ -8,6 +8,7 @@ #include #include #include +#include #include #include @@ -49,6 +50,11 @@ static unsigned long long riscv_clocksource_rdtime(struct clocksource *cs) return get_cycles64(); } +static u64 riscv_sched_clock(void) +{ + return get_cycles64(); +} + static DEFINE_PER_CPU(struct clocksource, riscv_clocksource) = { .name = "riscv_clocksource", .rating = 300, @@ -97,6 +103,9 @@ static int __init riscv_timer_init_dt(struct device_node *n) cs = per_cpu_ptr(&riscv_clocksource, cpuid); clocksource_register_hz(cs, riscv_timebase); + sched_clock_register(riscv_sched_clock, + BITS_PER_LONG, riscv_timebase); + error = cpuhp_setup_state(CPUHP_AP_RISCV_TIMER_STARTING, "clockevents/riscv/timer:starting", riscv_timer_starting_cpu, riscv_timer_dying_cpu);