/* * linux/kernel/irq/chip.c * * Copyright (C) 1992, 1998-2006 Linus Torvalds, Ingo Molnar * Copyright (C) 2005-2006, Thomas Gleixner, Russell King * * This file contains the core interrupt handling code, for irq-chip * based architectures. * * Detailed information is available in Documentation/DocBook/genericirq */ #include #include #include #include #include #include #include "internals.h" /** * irq_set_chip - set the irq chip for an irq * @irq: irq number * @chip: pointer to irq chip description structure */ int irq_set_chip(unsigned int irq, struct irq_chip *chip) { unsigned long flags; struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); if (!desc) return -EINVAL; if (!chip) chip = &no_irq_chip; desc->irq_data.chip = chip; irq_put_desc_unlock(desc, flags); /* * For !CONFIG_SPARSE_IRQ make the irq show up in * allocated_irqs. */ irq_mark_irq(irq); return 0; } EXPORT_SYMBOL(irq_set_chip); /** * irq_set_type - set the irq trigger type for an irq * @irq: irq number * @type: IRQ_TYPE_{LEVEL,EDGE}_* value - see include/linux/irq.h */ int irq_set_irq_type(unsigned int irq, unsigned int type) { unsigned long flags; struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, IRQ_GET_DESC_CHECK_GLOBAL); int ret = 0; if (!desc) return -EINVAL; type &= IRQ_TYPE_SENSE_MASK; ret = __irq_set_trigger(desc, irq, type); irq_put_desc_busunlock(desc, flags); return ret; } EXPORT_SYMBOL(irq_set_irq_type); /** * irq_set_handler_data - set irq handler data for an irq * @irq: Interrupt number * @data: Pointer to interrupt specific data * * Set the hardware irq controller data for an irq */ int irq_set_handler_data(unsigned int irq, void *data) { unsigned long flags; struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); if (!desc) return -EINVAL; desc->irq_data.handler_data = data; irq_put_desc_unlock(desc, flags); return 0; } EXPORT_SYMBOL(irq_set_handler_data); /** * irq_set_msi_desc_off - set MSI descriptor data for an irq at offset * @irq_base: Interrupt number base * @irq_offset: Interrupt number offset * @entry: Pointer to MSI descriptor data * * Set the MSI descriptor entry for an irq at offset */ int irq_set_msi_desc_off(unsigned int irq_base, unsigned int irq_offset, struct msi_desc *entry) { unsigned long flags; struct irq_desc *desc = irq_get_desc_lock(irq_base + irq_offset, &flags, IRQ_GET_DESC_CHECK_GLOBAL); if (!desc) return -EINVAL; desc->irq_data.msi_desc = entry; if (entry && !irq_offset) entry->irq = irq_base; irq_put_desc_unlock(desc, flags); return 0; } /** * irq_set_msi_desc - set MSI descriptor data for an irq * @irq: Interrupt number * @entry: Pointer to MSI descriptor data * * Set the MSI descriptor entry for an irq */ int irq_set_msi_desc(unsigned int irq, struct msi_desc *entry) { return irq_set_msi_desc_off(irq, 0, entry); } /** * irq_set_chip_data - set irq chip data for an irq * @irq: Interrupt number * @data: Pointer to chip specific data * * Set the hardware irq chip data for an irq */ int irq_set_chip_data(unsigned int irq, void *data) { unsigned long flags; struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); if (!desc) return -EINVAL; desc->irq_data.chip_data = data; irq_put_desc_unlock(desc, flags); return 0; } EXPORT_SYMBOL(irq_set_chip_data); struct irq_data *irq_get_irq_data(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); return desc ? &desc->irq_data : NULL; } EXPORT_SYMBOL_GPL(irq_get_irq_data); static void irq_state_clr_disabled(struct irq_desc *desc) { irqd_clear(&desc->irq_data, IRQD_IRQ_DISABLED); } static void irq_state_set_disabled(struct irq_desc *desc) { irqd_set(&desc->irq_data, IRQD_IRQ_DISABLED); } static void irq_state_clr_masked(struct irq_desc *desc) { irqd_clear(&desc->irq_data, IRQD_IRQ_MASKED); } static void irq_state_set_masked(struct irq_desc *desc) { irqd_set(&desc->irq_data, IRQD_IRQ_MASKED); } int irq_startup(struct irq_desc *desc, bool resend) { int ret = 0; irq_state_clr_disabled(desc); desc->depth = 0; if (desc->irq_data.chip->irq_startup) { ret = desc->irq_data.chip->irq_startup(&desc->irq_data); irq_state_clr_masked(desc); } else { irq_enable(desc); } if (resend) check_irq_resend(desc, desc->irq_data.irq); return ret; } void irq_shutdown(struct irq_desc *desc) { irq_state_set_disabled(desc); desc->depth = 1; if (desc->irq_data.chip->irq_shutdown) desc->irq_data.chip->irq_shutdown(&desc->irq_data); else if (desc->irq_data.chip->irq_disable) desc->irq_data.chip->irq_disable(&desc->irq_data); else desc->irq_data.chip->irq_mask(&desc->irq_data); irq_state_set_masked(desc); } void irq_enable(struct irq_desc *desc) { irq_state_clr_disabled(desc); if (desc->irq_data.chip->irq_enable) desc->irq_data.chip->irq_enable(&desc->irq_data); else desc->irq_data.chip->irq_unmask(&desc->irq_data); irq_state_clr_masked(desc); } /** * irq_disable - Mark interrupt disabled * @desc: irq descriptor which should be disabled * * If the chip does not implement the irq_disable callback, we * use a lazy disable approach. That means we mark the interrupt * disabled, but leave the hardware unmasked. That's an * optimization because we avoid the hardware access for the * common case where no interrupt happens after we marked it * disabled. If an interrupt happens, then the interrupt flow * handler masks the line at the hardware level and marks it * pending. */ void irq_disable(struct irq_desc *desc) { irq_state_set_disabled(desc); if (desc->irq_data.chip->irq_disable) { desc->irq_data.chip->irq_disable(&desc->irq_data); irq_state_set_masked(desc); } } void irq_percpu_enable(struct irq_desc *desc, unsigned int cpu) { if (desc->irq_data.chip->irq_enable) desc->irq_data.chip->irq_enable(&desc->irq_data); else desc->irq_data.chip->irq_unmask(&desc->irq_data); cpumask_set_cpu(cpu, desc->percpu_enabled); } void irq_percpu_disable(struct irq_desc *desc, unsigned int cpu) { if (desc->irq_data.chip->irq_disable) desc->irq_data.chip->irq_disable(&desc->irq_data); else desc->irq_data.chip->irq_mask(&desc->irq_data); cpumask_clear_cpu(cpu, desc->percpu_enabled); } static inline void mask_ack_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_mask_ack) desc->irq_data.chip->irq_mask_ack(&desc->irq_data); else { desc->irq_data.chip->irq_mask(&desc->irq_data); if (desc->irq_data.chip->irq_ack) desc->irq_data.chip->irq_ack(&desc->irq_data); } irq_state_set_masked(desc); } void mask_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_mask) { desc->irq_data.chip->irq_mask(&desc->irq_data); irq_state_set_masked(desc); } } void unmask_irq(struct irq_desc *desc) { if (desc->irq_data.chip->irq_unmask) { desc->irq_data.chip->irq_unmask(&desc->irq_data); irq_state_clr_masked(desc); } } void unmask_threaded_irq(struct irq_desc *desc) { struct irq_chip *chip = desc->irq_data.chip; if (chip->flags & IRQCHIP_EOI_THREADED) chip->irq_eoi(&desc->irq_data); if (chip->irq_unmask) { chip->irq_unmask(&desc->irq_data); irq_state_clr_masked(desc); } } /* * handle_nested_irq - Handle a nested irq from a irq thread * @irq: the interrupt number * * Handle interrupts which are nested into a threaded interrupt * handler. The handler function is called inside the calling * threads context. */ void handle_nested_irq(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); struct irqaction *action; irqreturn_t action_ret; might_sleep(); raw_spin_lock_irq(&desc->lock); desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); action = desc->action; if (unlikely(!action || irqd_irq_disabled(&desc->irq_data))) { desc->istate |= IRQS_PENDING; goto out_unlock; } irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); raw_spin_unlock_irq(&desc->lock); action_ret = action->thread_fn(action->irq, action->dev_id); if (!noirqdebug) note_interrupt(irq, desc, action_ret); raw_spin_lock_irq(&desc->lock); irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); out_unlock: raw_spin_unlock_irq(&desc->lock); } EXPORT_SYMBOL_GPL(handle_nested_irq); static bool irq_check_poll(struct irq_desc *desc) { if (!(desc->istate & IRQS_POLL_INPROGRESS)) return false; return irq_wait_for_poll(desc); } static bool irq_may_run(struct irq_desc *desc) { if (!irqd_irq_inprogress(&desc->irq_data)) return true; return irq_check_poll(desc); } /** * handle_simple_irq - Simple and software-decoded IRQs. * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Simple interrupts are either sent from a demultiplexing interrupt * handler or come from hardware, where no interrupt hardware control * is necessary. * * Note: The caller is expected to handle the ack, clear, mask and * unmask issues if necessary. */ void handle_simple_irq(unsigned int irq, struct irq_desc *desc) { raw_spin_lock(&desc->lock); if (!irq_may_run(desc)) goto out_unlock; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { desc->istate |= IRQS_PENDING; goto out_unlock; } handle_irq_event(desc); out_unlock: raw_spin_unlock(&desc->lock); } EXPORT_SYMBOL_GPL(handle_simple_irq); /* * Called unconditionally from handle_level_irq() and only for oneshot * interrupts from handle_fasteoi_irq() */ static void cond_unmask_irq(struct irq_desc *desc) { /* * We need to unmask in the following cases: * - Standard level irq (IRQF_ONESHOT is not set) * - Oneshot irq which did not wake the thread (caused by a * spurious interrupt or a primary handler handling it * completely). */ if (!irqd_irq_disabled(&desc->irq_data) && irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) unmask_irq(desc); } /** * handle_level_irq - Level type irq handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Level type interrupts are active as long as the hardware line has * the active level. This may require to mask the interrupt and unmask * it after the associated handler has acknowledged the device, so the * interrupt line is back to inactive. */ void handle_level_irq(unsigned int irq, struct irq_desc *desc) { raw_spin_lock(&desc->lock); mask_ack_irq(desc); if (!irq_may_run(desc)) goto out_unlock; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); /* * If its disabled or no action available * keep it masked and get out of here */ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { desc->istate |= IRQS_PENDING; goto out_unlock; } handle_irq_event(desc); cond_unmask_irq(desc); out_unlock: raw_spin_unlock(&desc->lock); } EXPORT_SYMBOL_GPL(handle_level_irq); #ifdef CONFIG_IRQ_PREFLOW_FASTEOI static inline void preflow_handler(struct irq_desc *desc) { if (desc->preflow_handler) desc->preflow_handler(&desc->irq_data); } #else static inline void preflow_handler(struct irq_desc *desc) { } #endif static void cond_unmask_eoi_irq(struct irq_desc *desc, struct irq_chip *chip) { if (!(desc->istate & IRQS_ONESHOT)) { chip->irq_eoi(&desc->irq_data); return; } /* * We need to unmask in the following cases: * - Oneshot irq which did not wake the thread (caused by a * spurious interrupt or a primary handler handling it * completely). */ if (!irqd_irq_disabled(&desc->irq_data) && irqd_irq_masked(&desc->irq_data) && !desc->threads_oneshot) { chip->irq_eoi(&desc->irq_data); unmask_irq(desc); } else if (!(chip->flags & IRQCHIP_EOI_THREADED)) { chip->irq_eoi(&desc->irq_data); } } /** * handle_fasteoi_irq - irq handler for transparent controllers * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Only a single callback will be issued to the chip: an ->eoi() * call when the interrupt has been serviced. This enables support * for modern forms of interrupt handlers, which handle the flow * details in hardware, transparently. */ void handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) { struct irq_chip *chip = desc->irq_data.chip; raw_spin_lock(&desc->lock); if (!irq_may_run(desc)) goto out; desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); kstat_incr_irqs_this_cpu(irq, desc); /* * If its disabled or no action available * then mask it and get out of here: */ if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) { desc->istate |= IRQS_PENDING; mask_irq(desc); goto out; } if (desc->istate & IRQS_ONESHOT) mask_irq(desc); preflow_handler(desc); handle_irq_event(desc); cond_unmask_eoi_irq(desc, chip); raw_spin_unlock(&desc->lock); return; out: if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED)) chip->irq_eoi(&desc->irq_data); raw_spin_unlock(&desc->lock); } /** * handle_edge_irq - edge type IRQ handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Interrupt occures on the falling and/or rising edge of a hardware * signal. The occurrence is latched into the irq controller hardware * and must be acked in order to be reenabled. After the ack another * interrupt can happen on the same source even before the first one * is handled by the associated event handler. If this happens it * might be necessary to disable (mask) the interrupt depending on the * controller hardware. This requires to reenable the interrupt inside * of the loop which handles the interrupts which have arrived while * the handler was running. If all pending interrupts are handled, the * loop is left. */ void handle_edge_irq(unsigned int irq, struct irq_desc *desc) { raw_spin_lock(&desc->lock); desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); if (!irq_may_run(desc)) { desc->istate |= IRQS_PENDING; mask_ack_irq(desc); goto out_unlock; } /* * If its disabled or no action available then mask it and get * out of here. */ if (irqd_irq_disabled(&desc->irq_data) || !desc->action) { desc->istate |= IRQS_PENDING; mask_ack_irq(desc); goto out_unlock; } kstat_incr_irqs_this_cpu(irq, desc); /* Start handling the irq */ desc->irq_data.chip->irq_ack(&desc->irq_data); do { if (unlikely(!desc->action)) { mask_irq(desc); goto out_unlock; } /* * When another irq arrived while we were handling * one, we could have masked the irq. * Renable it, if it was not disabled in meantime. */ if (unlikely(desc->istate & IRQS_PENDING)) { if (!irqd_irq_disabled(&desc->irq_data) && irqd_irq_masked(&desc->irq_data)) unmask_irq(desc); } handle_irq_event(desc); } while ((desc->istate & IRQS_PENDING) && !irqd_irq_disabled(&desc->irq_data)); out_unlock: raw_spin_unlock(&desc->lock); } EXPORT_SYMBOL(handle_edge_irq); #ifdef CONFIG_IRQ_EDGE_EOI_HANDLER /** * handle_edge_eoi_irq - edge eoi type IRQ handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Similar as the above handle_edge_irq, but using eoi and w/o the * mask/unmask logic. */ void handle_edge_eoi_irq(unsigned int irq, struct irq_desc *desc) { struct irq_chip *chip = irq_desc_get_chip(desc); raw_spin_lock(&desc->lock); desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING); if (!irq_may_run(desc)) { desc->istate |= IRQS_PENDING; goto out_eoi; } /* * If its disabled or no action available then mask it and get * out of here. */ if (irqd_irq_disabled(&desc->irq_data) || !desc->action) { desc->istate |= IRQS_PENDING; goto out_eoi; } kstat_incr_irqs_this_cpu(irq, desc); do { if (unlikely(!desc->action)) goto out_eoi; handle_irq_event(desc); } while ((desc->istate & IRQS_PENDING) && !irqd_irq_disabled(&desc->irq_data)); out_eoi: chip->irq_eoi(&desc->irq_data); raw_spin_unlock(&desc->lock); } #endif /** * handle_percpu_irq - Per CPU local irq handler * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Per CPU interrupts on SMP machines without locking requirements */ void handle_percpu_irq(unsigned int irq, struct irq_desc *desc) { struct irq_chip *chip = irq_desc_get_chip(desc); kstat_incr_irqs_this_cpu(irq, desc); if (chip->irq_ack) chip->irq_ack(&desc->irq_data); handle_irq_event_percpu(desc, desc->action); if (chip->irq_eoi) chip->irq_eoi(&desc->irq_data); } /** * handle_percpu_devid_irq - Per CPU local irq handler with per cpu dev ids * @irq: the interrupt number * @desc: the interrupt description structure for this irq * * Per CPU interrupts on SMP machines without locking requirements. Same as * handle_percpu_irq() above but with the following extras: * * action->percpu_dev_id is a pointer to percpu variables which * contain the real device id for the cpu on which this handler is * called */ void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc) { struct irq_chip *chip = irq_desc_get_chip(desc); struct irqaction *action = desc->action; void *dev_id = __this_cpu_ptr(action->percpu_dev_id); irqreturn_t res; kstat_incr_irqs_this_cpu(irq, desc); if (chip->irq_ack) chip->irq_ack(&desc->irq_data); trace_irq_handler_entry(irq, action); res = action->handler(irq, dev_id); trace_irq_handler_exit(irq, action, res); if (chip->irq_eoi) chip->irq_eoi(&desc->irq_data); } void __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, const char *name) { unsigned long flags; struct irq_desc *desc = irq_get_desc_buslock(irq, &flags, 0); if (!desc) return; if (!handle) { handle = handle_bad_irq; } else { if (WARN_ON(desc->irq_data.chip == &no_irq_chip)) goto out; } /* Uninstall? */ if (handle == handle_bad_irq) { if (desc->irq_data.chip != &no_irq_chip) mask_ack_irq(desc); irq_state_set_disabled(desc); desc->depth = 1; } desc->handle_irq = handle; desc->name = name; if (handle != handle_bad_irq && is_chained) { irq_settings_set_noprobe(desc); irq_settings_set_norequest(desc); irq_settings_set_nothread(desc); irq_startup(desc, true); } out: irq_put_desc_busunlock(desc, flags); } EXPORT_SYMBOL_GPL(__irq_set_handler); void irq_set_chip_and_handler_name(unsigned int irq, struct irq_chip *chip, irq_flow_handler_t handle, const char *name) { irq_set_chip(irq, chip); __irq_set_handler(irq, handle, 0, name); } EXPORT_SYMBOL_GPL(irq_set_chip_and_handler_name); void irq_modify_status(unsigned int irq, unsigned long clr, unsigned long set) { unsigned long flags; struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); if (!desc) return; irq_settings_clr_and_set(desc, clr, set); irqd_clear(&desc->irq_data, IRQD_NO_BALANCING | IRQD_PER_CPU | IRQD_TRIGGER_MASK | IRQD_LEVEL | IRQD_MOVE_PCNTXT); if (irq_settings_has_no_balance_set(desc)) irqd_set(&desc->irq_data, IRQD_NO_BALANCING); if (irq_settings_is_per_cpu(desc)) irqd_set(&desc->irq_data, IRQD_PER_CPU); if (irq_settings_can_move_pcntxt(desc)) irqd_set(&desc->irq_data, IRQD_MOVE_PCNTXT); if (irq_settings_is_level(desc)) irqd_set(&desc->irq_data, IRQD_LEVEL); irqd_set(&desc->irq_data, irq_settings_get_trigger_mask(desc)); irq_put_desc_unlock(desc, flags); } EXPORT_SYMBOL_GPL(irq_modify_status); /** * irq_cpu_online - Invoke all irq_cpu_online functions. * * Iterate through all irqs and invoke the chip.irq_cpu_online() * for each. */ void irq_cpu_online(void) { struct irq_desc *desc; struct irq_chip *chip; unsigned long flags; unsigned int irq; for_each_active_irq(irq) { desc = irq_to_desc(irq); if (!desc) continue; raw_spin_lock_irqsave(&desc->lock, flags); chip = irq_data_get_irq_chip(&desc->irq_data); if (chip && chip->irq_cpu_online && (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) || !irqd_irq_disabled(&desc->irq_data))) chip->irq_cpu_online(&desc->irq_data); raw_spin_unlock_irqrestore(&desc->lock, flags); } } /** * irq_cpu_offline - Invoke all irq_cpu_offline functions. * * Iterate through all irqs and invoke the chip.irq_cpu_offline() * for each. */ void irq_cpu_offline(void) { struct irq_desc *desc; struct irq_chip *chip; unsigned long flags; unsigned int irq; for_each_active_irq(irq) { desc = irq_to_desc(irq); if (!desc) continue; raw_spin_lock_irqsave(&desc->lock, flags); chip = irq_data_get_irq_chip(&desc->irq_data); if (chip && chip->irq_cpu_offline && (!(chip->flags & IRQCHIP_ONOFFLINE_ENABLED) || !irqd_irq_disabled(&desc->irq_data))) chip->irq_cpu_offline(&desc->irq_data); raw_spin_unlock_irqrestore(&desc->lock, flags); } }