diff options
Diffstat (limited to 'drivers/clocksource/timer-riscv.c')
| -rw-r--r-- | drivers/clocksource/timer-riscv.c | 144 |
1 files changed, 101 insertions, 43 deletions
diff --git a/drivers/clocksource/timer-riscv.c b/drivers/clocksource/timer-riscv.c index a0d66fabf073..4d7cf338824a 100644 --- a/drivers/clocksource/timer-riscv.c +++ b/drivers/clocksource/timer-riscv.c @@ -10,6 +10,7 @@ #define pr_fmt(fmt) "riscv-timer: " fmt +#include <linux/acpi.h> #include <linux/clocksource.h> #include <linux/clockchips.h> #include <linux/cpu.h> @@ -21,20 +22,32 @@ #include <linux/io-64-nonatomic-lo-hi.h> #include <linux/interrupt.h> #include <linux/of_irq.h> +#include <linux/limits.h> #include <clocksource/timer-riscv.h> #include <asm/smp.h> -#include <asm/hwcap.h> +#include <asm/cpufeature.h> #include <asm/sbi.h> #include <asm/timex.h> static DEFINE_STATIC_KEY_FALSE(riscv_sstc_available); +static bool riscv_timer_cannot_wake_cpu; + +static void riscv_clock_event_stop(void) +{ + if (static_branch_likely(&riscv_sstc_available)) { + csr_write(CSR_STIMECMP, ULONG_MAX); + if (IS_ENABLED(CONFIG_32BIT)) + csr_write(CSR_STIMECMPH, ULONG_MAX); + } else { + sbi_set_timer(U64_MAX); + } +} static int riscv_clock_next_event(unsigned long delta, struct clock_event_device *ce) { u64 next_tval = get_cycles64() + delta; - csr_set(CSR_IE, IE_TIE); if (static_branch_likely(&riscv_sstc_available)) { #if defined(CONFIG_32BIT) csr_write(CSR_STIMECMP, next_tval & 0xFFFFFFFF); @@ -48,12 +61,19 @@ static int riscv_clock_next_event(unsigned long delta, return 0; } +static int riscv_clock_shutdown(struct clock_event_device *evt) +{ + riscv_clock_event_stop(); + return 0; +} + static unsigned int riscv_clock_event_irq; static DEFINE_PER_CPU(struct clock_event_device, riscv_clock_event) = { .name = "riscv_timer_clockevent", .features = CLOCK_EVT_FEAT_ONESHOT, .rating = 100, .set_next_event = riscv_clock_next_event, + .set_state_shutdown = riscv_clock_shutdown, }; /* @@ -73,19 +93,31 @@ static u64 notrace riscv_sched_clock(void) static struct clocksource riscv_clocksource = { .name = "riscv_clocksource", - .rating = 300, + .rating = 400, .mask = CLOCKSOURCE_MASK(64), .flags = CLOCK_SOURCE_IS_CONTINUOUS, .read = riscv_clocksource_rdtime, +#if IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY) + .vdso_clock_mode = VDSO_CLOCKMODE_ARCHTIMER, +#else + .vdso_clock_mode = VDSO_CLOCKMODE_NONE, +#endif }; static int riscv_timer_starting_cpu(unsigned int cpu) { struct clock_event_device *ce = per_cpu_ptr(&riscv_clock_event, cpu); + /* Clear timer interrupt */ + riscv_clock_event_stop(); + ce->cpumask = cpumask_of(cpu); ce->irq = riscv_clock_event_irq; - clockevents_config_and_register(ce, riscv_timebase, 100, 0x7fffffff); + if (riscv_timer_cannot_wake_cpu) + ce->features |= CLOCK_EVT_FEAT_C3STOP; + if (static_branch_likely(&riscv_sstc_available)) + ce->rating = 450; + clockevents_config_and_register(ce, riscv_timebase, 100, ULONG_MAX); enable_percpu_irq(riscv_clock_event_irq, irq_get_trigger_type(riscv_clock_event_irq)); @@ -94,7 +126,13 @@ static int riscv_timer_starting_cpu(unsigned int cpu) static int riscv_timer_dying_cpu(unsigned int cpu) { + /* + * Stop the timer when the cpu is going to be offline otherwise + * the timer interrupt may be pending while performing power-down. + */ + riscv_clock_event_stop(); disable_percpu_irq(riscv_clock_event_irq); + return 0; } @@ -110,60 +148,34 @@ static irqreturn_t riscv_timer_interrupt(int irq, void *dev_id) { struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event); - csr_clear(CSR_IE, IE_TIE); + riscv_clock_event_stop(); evdev->event_handler(evdev); return IRQ_HANDLED; } -static int __init riscv_timer_init_dt(struct device_node *n) +static int __init riscv_timer_init_common(void) { - int cpuid, error; - unsigned long hartid; - struct device_node *child; + int error; struct irq_domain *domain; + struct fwnode_handle *intc_fwnode = riscv_get_intc_hwnode(); - error = riscv_of_processor_hartid(n, &hartid); - if (error < 0) { - pr_warn("Not valid hartid for node [%pOF] error = [%lu]\n", - n, hartid); - return error; - } - - cpuid = riscv_hartid_to_cpuid(hartid); - if (cpuid < 0) { - pr_warn("Invalid cpuid for hartid [%lu]\n", hartid); - return cpuid; - } - - if (cpuid != smp_processor_id()) - return 0; - - domain = NULL; - child = of_get_compatible_child(n, "riscv,cpu-intc"); - if (!child) { - pr_err("Failed to find INTC node [%pOF]\n", n); - return -ENODEV; - } - domain = irq_find_host(child); - of_node_put(child); + domain = irq_find_matching_fwnode(intc_fwnode, DOMAIN_BUS_ANY); if (!domain) { - pr_err("Failed to find IRQ domain for node [%pOF]\n", n); + pr_err("Failed to find irq_domain for INTC node [%pfwP]\n", + intc_fwnode); return -ENODEV; } riscv_clock_event_irq = irq_create_mapping(domain, RV_IRQ_TIMER); if (!riscv_clock_event_irq) { - pr_err("Failed to map timer interrupt for node [%pOF]\n", n); + pr_err("Failed to map timer interrupt for node [%pfwP]\n", intc_fwnode); return -ENODEV; } - pr_info("%s: Registering clocksource cpuid [%d] hartid [%lu]\n", - __func__, cpuid, hartid); error = clocksource_register_hz(&riscv_clocksource, riscv_timebase); if (error) { - pr_err("RISCV timer register failed [%d] for cpu = [%d]\n", - error, cpuid); + pr_err("RISCV timer registration failed [%d]\n", error); return error; } @@ -177,6 +189,11 @@ static int __init riscv_timer_init_dt(struct device_node *n) return error; } + if (riscv_isa_extension_available(NULL, SSTC)) { + pr_info("Timer interrupt in S-mode is available via sstc extension\n"); + static_branch_enable(&riscv_sstc_available); + } + error = cpuhp_setup_state(CPUHP_AP_RISCV_TIMER_STARTING, "clockevents/riscv/timer:starting", riscv_timer_starting_cpu, riscv_timer_dying_cpu); @@ -184,12 +201,53 @@ static int __init riscv_timer_init_dt(struct device_node *n) pr_err("cpu hp setup state failed for RISCV timer [%d]\n", error); - if (riscv_isa_extension_available(NULL, SSTC)) { - pr_info("Timer interrupt in S-mode is available via sstc extension\n"); - static_branch_enable(&riscv_sstc_available); + return error; +} + +static int __init riscv_timer_init_dt(struct device_node *n) +{ + int cpuid, error; + unsigned long hartid; + struct device_node *child; + + error = riscv_of_processor_hartid(n, &hartid); + if (error < 0) { + pr_warn("Invalid hartid for node [%pOF] error = [%lu]\n", + n, hartid); + return error; } - return error; + cpuid = riscv_hartid_to_cpuid(hartid); + if (cpuid < 0) { + pr_warn("Invalid cpuid for hartid [%lu]\n", hartid); + return cpuid; + } + + if (cpuid != smp_processor_id()) + return 0; + + child = of_find_compatible_node(NULL, NULL, "riscv,timer"); + if (child) { + riscv_timer_cannot_wake_cpu = of_property_read_bool(child, + "riscv,timer-cannot-wake-cpu"); + of_node_put(child); + } + + return riscv_timer_init_common(); } TIMER_OF_DECLARE(riscv_timer, "riscv", riscv_timer_init_dt); + +#ifdef CONFIG_ACPI +static int __init riscv_timer_acpi_init(struct acpi_table_header *table) +{ + struct acpi_table_rhct *rhct = (struct acpi_table_rhct *)table; + + riscv_timer_cannot_wake_cpu = rhct->flags & ACPI_RHCT_TIMER_CANNOT_WAKEUP_CPU; + + return riscv_timer_init_common(); +} + +TIMER_ACPI_DECLARE(aclint_mtimer, ACPI_SIG_RHCT, riscv_timer_acpi_init); + +#endif |