diff options
Diffstat (limited to 'drivers/clocksource/timer-riscv.c')
| -rw-r--r-- | drivers/clocksource/timer-riscv.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c index 470c7ef02ea4..4e54856ce2a5 100644 --- a/drivers/clocksource/timer-riscv.c +++ b/drivers/clocksource/timer-riscv.c @@ -3,9 +3,9 @@ * Copyright (C) 2012 Regents of the University of California * Copyright (C) 2017 SiFive * - * All RISC-V systems have a timer attached to every hart. These timers can be - * read from the "time" and "timeh" CSRs, and can use the SBI to setup - * events. + * All RISC-V systems have a timer attached to every hart. These timers can + * either be read from the "time" and "timeh" CSRs, and can use the SBI to + * setup events, or directly accessed using MMIO registers. */ #include <linux/clocksource.h> #include <linux/clockchips.h> @@ -13,14 +13,29 @@ #include <linux/delay.h> #include <linux/irq.h> #include <linux/sched_clock.h> +#include <linux/io-64-nonatomic-lo-hi.h> #include <asm/smp.h> #include <asm/sbi.h> +u64 __iomem *riscv_time_cmp; +u64 __iomem *riscv_time_val; + +static inline void mmio_set_timer(u64 val) +{ + void __iomem *r; + + r = riscv_time_cmp + cpuid_to_hartid_map(smp_processor_id()); + writeq_relaxed(val, r); +} + static int riscv_clock_next_event(unsigned long delta, struct clock_event_device *ce) { - csr_set(sie, SIE_STIE); - sbi_set_timer(get_cycles64() + delta); + csr_set(CSR_IE, IE_TIE); + if (IS_ENABLED(CONFIG_RISCV_SBI)) + sbi_set_timer(get_cycles64() + delta); + else + mmio_set_timer(get_cycles64() + delta); return 0; } @@ -61,13 +76,13 @@ static int riscv_timer_starting_cpu(unsigned int cpu) ce->cpumask = cpumask_of(cpu); clockevents_config_and_register(ce, riscv_timebase, 100, 0x7fffffff); - csr_set(sie, SIE_STIE); + csr_set(CSR_IE, IE_TIE); return 0; } static int riscv_timer_dying_cpu(unsigned int cpu) { - csr_clear(sie, SIE_STIE); + csr_clear(CSR_IE, IE_TIE); return 0; } @@ -76,7 +91,7 @@ void riscv_timer_interrupt(void) { struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event); - csr_clear(sie, SIE_STIE); + csr_clear(CSR_IE, IE_TIE); evdev->event_handler(evdev); } |