diff options
Diffstat (limited to 'drivers/clocksource/arm_arch_timer.c')
-rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 66 |
1 files changed, 44 insertions, 22 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 061476e92db7..57cb2f00fc07 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -77,6 +77,7 @@ static bool arch_timer_mem_use_virtual; static bool arch_counter_suspend_stop; static bool vdso_default = true; +static cpumask_t evtstrm_available = CPU_MASK_NONE; static bool evtstrm_enable = IS_ENABLED(CONFIG_ARM_ARCH_TIMER_EVTSTREAM); static int __init early_evtstrm_cfg(char *buf) @@ -319,8 +320,7 @@ static u64 notrace arm64_858921_read_cntvct_el0(void) #endif #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND -DEFINE_PER_CPU(const struct arch_timer_erratum_workaround *, - timer_unstable_counter_workaround); +DEFINE_PER_CPU(const struct arch_timer_erratum_workaround *, timer_unstable_counter_workaround); EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); DEFINE_STATIC_KEY_FALSE(arch_timer_read_ool_enabled); @@ -767,6 +767,7 @@ static void arch_timer_evtstrm_enable(int divider) #ifdef CONFIG_COMPAT compat_elf_hwcap |= COMPAT_HWCAP_EVTSTRM; #endif + cpumask_set_cpu(smp_processor_id(), &evtstrm_available); } static void arch_timer_configure_evtstream(void) @@ -891,6 +892,16 @@ u32 arch_timer_get_rate(void) return arch_timer_rate; } +bool arch_timer_evtstrm_available(void) +{ + /* + * We might get called from a preemptible context. This is fine + * because availability of the event stream should be always the same + * for a preemptible context and context where we might resume a task. + */ + return cpumask_test_cpu(raw_smp_processor_id(), &evtstrm_available); +} + static u64 arch_counter_get_cntvct_mem(void) { u32 vct_lo, vct_hi, tmp_hi; @@ -956,6 +967,8 @@ static int arch_timer_dying_cpu(unsigned int cpu) { struct clock_event_device *clk = this_cpu_ptr(arch_timer_evt); + cpumask_clear_cpu(smp_processor_id(), &evtstrm_available); + arch_timer_stop(clk); return 0; } @@ -965,10 +978,16 @@ static DEFINE_PER_CPU(unsigned long, saved_cntkctl); static int arch_timer_cpu_pm_notify(struct notifier_block *self, unsigned long action, void *hcpu) { - if (action == CPU_PM_ENTER) + if (action == CPU_PM_ENTER) { __this_cpu_write(saved_cntkctl, arch_timer_get_cntkctl()); - else if (action == CPU_PM_ENTER_FAILED || action == CPU_PM_EXIT) + + cpumask_clear_cpu(smp_processor_id(), &evtstrm_available); + } else if (action == CPU_PM_ENTER_FAILED || action == CPU_PM_EXIT) { arch_timer_set_cntkctl(__this_cpu_read(saved_cntkctl)); + + if (elf_hwcap & HWCAP_EVTSTRM) + cpumask_set_cpu(smp_processor_id(), &evtstrm_available); + } return NOTIFY_OK; } @@ -1044,7 +1063,6 @@ static int __init arch_timer_register(void) if (err) goto out_unreg_notify; - /* Register and immediately configure the timer on the boot CPU */ err = cpuhp_setup_state(CPUHP_AP_ARM_ARCH_TIMER_STARTING, "clockevents/arm/arch_timer:starting", @@ -1295,10 +1313,6 @@ arch_timer_mem_find_best_frame(struct arch_timer_mem *timer_mem) iounmap(cntctlbase); - if (!best_frame) - pr_err("Unable to find a suitable frame in timer @ %pa\n", - &timer_mem->cntctlbase); - return best_frame; } @@ -1399,6 +1413,8 @@ static int __init arch_timer_mem_of_init(struct device_node *np) frame = arch_timer_mem_find_best_frame(timer_mem); if (!frame) { + pr_err("Unable to find a suitable frame in timer @ %pa\n", + &timer_mem->cntctlbase); ret = -EINVAL; goto out; } @@ -1447,7 +1463,7 @@ arch_timer_mem_verify_cntfrq(struct arch_timer_mem *timer_mem) static int __init arch_timer_mem_acpi_init(int platform_timer_count) { struct arch_timer_mem *timers, *timer; - struct arch_timer_mem_frame *frame; + struct arch_timer_mem_frame *frame, *best_frame = NULL; int timer_count, i, ret = 0; timers = kcalloc(platform_timer_count, sizeof(*timers), @@ -1459,14 +1475,6 @@ static int __init arch_timer_mem_acpi_init(int platform_timer_count) if (ret || !timer_count) goto out; - for (i = 0; i < timer_count; i++) { - ret = arch_timer_mem_verify_cntfrq(&timers[i]); - if (ret) { - pr_err("Disabling MMIO timers due to CNTFRQ mismatch\n"); - goto out; - } - } - /* * While unlikely, it's theoretically possible that none of the frames * in a timer expose the combination of feature we want. @@ -1475,12 +1483,26 @@ static int __init arch_timer_mem_acpi_init(int platform_timer_count) timer = &timers[i]; frame = arch_timer_mem_find_best_frame(timer); - if (frame) - break; + if (!best_frame) + best_frame = frame; + + ret = arch_timer_mem_verify_cntfrq(timer); + if (ret) { + pr_err("Disabling MMIO timers due to CNTFRQ mismatch\n"); + goto out; + } + + if (!best_frame) /* implies !frame */ + /* + * Only complain about missing suitable frames if we + * haven't already found one in a previous iteration. + */ + pr_err("Unable to find a suitable frame in timer @ %pa\n", + &timer->cntctlbase); } - if (frame) - ret = arch_timer_mem_frame_register(frame); + if (best_frame) + ret = arch_timer_mem_frame_register(best_frame); out: kfree(timers); return ret; |