diff options
Diffstat (limited to 'kernel/irq')
| -rw-r--r-- | kernel/irq/Kconfig | 10 | ||||
| -rw-r--r-- | kernel/irq/autoprobe.c | 4 | ||||
| -rw-r--r-- | kernel/irq/chip.c | 47 | ||||
| -rw-r--r-- | kernel/irq/handle.c | 14 | ||||
| -rw-r--r-- | kernel/irq/internals.h | 4 | ||||
| -rw-r--r-- | kernel/irq/irqdomain.c | 828 | ||||
| -rw-r--r-- | kernel/irq/manage.c | 132 |
7 files changed, 855 insertions, 184 deletions
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 1f2dece9ad4c..cf1a4a68ce44 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -56,6 +56,16 @@ config GENERIC_IRQ_CHIP config IRQ_DOMAIN bool +config IRQ_DOMAIN_DEBUG + bool "Expose hardware/virtual IRQ mapping via debugfs" + depends on IRQ_DOMAIN && DEBUG_FS + help + This option will show the mapping relationship between hardware irq + numbers and Linux irq numbers. The mapping is exposed via debugfs + in the file "virq_mapping". + + If you don't know what this means you don't need it. + # Support forced irq threading config IRQ_FORCED_THREADING bool diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c index 342d8f44e401..0119b9d467ae 100644 --- a/kernel/irq/autoprobe.c +++ b/kernel/irq/autoprobe.c @@ -53,7 +53,7 @@ unsigned long probe_irq_on(void) if (desc->irq_data.chip->irq_set_type) desc->irq_data.chip->irq_set_type(&desc->irq_data, IRQ_TYPE_PROBE); - irq_startup(desc); + irq_startup(desc, false); } raw_spin_unlock_irq(&desc->lock); } @@ -70,7 +70,7 @@ unsigned long probe_irq_on(void) raw_spin_lock_irq(&desc->lock); if (!desc->action && irq_settings_can_probe(desc)) { desc->istate |= IRQS_AUTODETECT | IRQS_WAITING; - if (irq_startup(desc)) + if (irq_startup(desc, false)) desc->istate |= IRQS_PENDING; } raw_spin_unlock_irq(&desc->lock); diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index f7c543a801d9..6080f6bc8c33 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -16,6 +16,8 @@ #include <linux/interrupt.h> #include <linux/kernel_stat.h> +#include <trace/events/irq.h> + #include "internals.h" /** @@ -61,8 +63,7 @@ int irq_set_irq_type(unsigned int irq, unsigned int type) return -EINVAL; type &= IRQ_TYPE_SENSE_MASK; - if (type != IRQ_TYPE_NONE) - ret = __irq_set_trigger(desc, irq, type); + ret = __irq_set_trigger(desc, irq, type); irq_put_desc_busunlock(desc, flags); return ret; } @@ -157,19 +158,22 @@ 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) +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) { - int ret = desc->irq_data.chip->irq_startup(&desc->irq_data); + ret = desc->irq_data.chip->irq_startup(&desc->irq_data); irq_state_clr_masked(desc); - return ret; + } else { + irq_enable(desc); } - - irq_enable(desc); - return 0; + if (resend) + check_irq_resend(desc, desc->irq_data.irq); + return ret; } void irq_shutdown(struct irq_desc *desc) @@ -330,6 +334,24 @@ out_unlock: } 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 @@ -362,8 +384,8 @@ handle_level_irq(unsigned int irq, struct irq_desc *desc) handle_irq_event(desc); - if (!irqd_irq_disabled(&desc->irq_data) && !(desc->istate & IRQS_ONESHOT)) - unmask_irq(desc); + cond_unmask_irq(desc); + out_unlock: raw_spin_unlock(&desc->lock); } @@ -417,6 +439,9 @@ handle_fasteoi_irq(unsigned int irq, struct irq_desc *desc) preflow_handler(desc); handle_irq_event(desc); + if (desc->istate & IRQS_ONESHOT) + cond_unmask_irq(desc); + out_eoi: desc->irq_data.chip->irq_eoi(&desc->irq_data); out_unlock: @@ -625,7 +650,7 @@ __irq_set_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained, irq_settings_set_noprobe(desc); irq_settings_set_norequest(desc); irq_settings_set_nothread(desc); - irq_startup(desc); + irq_startup(desc, true); } out: irq_put_desc_busunlock(desc, flags); diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index 470d08c82bbe..6ff84e6a954c 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -60,7 +60,7 @@ static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action) * device interrupt, so no irq storm is lurking. If the * RUNTHREAD bit is already set, nothing to do. */ - if (test_bit(IRQTF_DIED, &action->thread_flags) || + if ((action->thread->flags & PF_EXITING) || test_and_set_bit(IRQTF_RUNTHREAD, &action->thread_flags)) return; @@ -110,6 +110,18 @@ static void irq_wake_thread(struct irq_desc *desc, struct irqaction *action) * threads_oneshot untouched and runs the thread another time. */ desc->threads_oneshot |= action->thread_mask; + + /* + * We increment the threads_active counter in case we wake up + * the irq thread. The irq thread decrements the counter when + * it returns from the handler or in the exit path and wakes + * up waiters which are stuck in synchronize_irq() when the + * active count becomes zero. synchronize_irq() is serialized + * against this code (hard irq handler) via IRQS_INPROGRESS + * like the finalize_oneshot() code. See comment above. + */ + atomic_inc(&desc->threads_active); + wake_up_process(action->thread); } diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index b7952316016a..8e5c56b3b7d9 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -20,14 +20,12 @@ extern bool noirqdebug; /* * Bits used by threaded handlers: * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run - * IRQTF_DIED - handler thread died * IRQTF_WARNED - warning "IRQ_WAKE_THREAD w/o thread_fn" has been printed * IRQTF_AFFINITY - irq thread is requested to adjust affinity * IRQTF_FORCED_THREAD - irq action is force threaded */ enum { IRQTF_RUNTHREAD, - IRQTF_DIED, IRQTF_WARNED, IRQTF_AFFINITY, IRQTF_FORCED_THREAD, @@ -67,7 +65,7 @@ extern int __irq_set_trigger(struct irq_desc *desc, unsigned int irq, extern void __disable_irq(struct irq_desc *desc, unsigned int irq, bool susp); extern void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume); -extern int irq_startup(struct irq_desc *desc); +extern int irq_startup(struct irq_desc *desc, bool resend); extern void irq_shutdown(struct irq_desc *desc); extern void irq_enable(struct irq_desc *desc); extern void irq_disable(struct irq_desc *desc); diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 1f9e26526b69..3601f3fbf67c 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -1,189 +1,793 @@ +#include <linux/debugfs.h> +#include <linux/hardirq.h> +#include <linux/interrupt.h> #include <linux/irq.h> +#include <linux/irqdesc.h> #include <linux/irqdomain.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/of.h> #include <linux/of_address.h> +#include <linux/seq_file.h> #include <linux/slab.h> +#include <linux/smp.h> +#include <linux/fs.h> + +#define IRQ_DOMAIN_MAP_LEGACY 0 /* driver allocated fixed range of irqs. + * ie. legacy 8259, gets irqs 1..15 */ +#define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */ +#define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */ +#define IRQ_DOMAIN_MAP_TREE 3 /* radix tree */ static LIST_HEAD(irq_domain_list); static DEFINE_MUTEX(irq_domain_mutex); +static DEFINE_MUTEX(revmap_trees_mutex); +static unsigned int irq_virq_count = NR_IRQS; +static struct irq_domain *irq_default_domain; + /** - * irq_domain_add() - Register an irq_domain - * @domain: ptr to initialized irq_domain structure + * irq_domain_alloc() - Allocate a new irq_domain data structure + * @of_node: optional device-tree node of the interrupt controller + * @revmap_type: type of reverse mapping to use + * @ops: map/unmap domain callbacks + * @host_data: Controller private data pointer * - * Registers an irq_domain structure. The irq_domain must at a minimum be - * initialized with an ops structure pointer, and either a ->to_irq hook or - * a valid irq_base value. Everything else is optional. + * Allocates and initialize and irq_domain structure. Caller is expected to + * register allocated irq_domain with irq_domain_register(). Returns pointer + * to IRQ domain, or NULL on failure. */ -void irq_domain_add(struct irq_domain *domain) +static struct irq_domain *irq_domain_alloc(struct device_node *of_node, + unsigned int revmap_type, + const struct irq_domain_ops *ops, + void *host_data) { - struct irq_data *d; - int hwirq, irq; + struct irq_domain *domain; - /* - * This assumes that the irq_domain owner has already allocated - * the irq_descs. This block will be removed when support for dynamic - * allocation of irq_descs is added to irq_domain. - */ - irq_domain_for_each_irq(domain, hwirq, irq) { - d = irq_get_irq_data(irq); - if (!d) { - WARN(1, "error: assigning domain to non existant irq_desc"); - return; - } - if (d->domain) { - /* things are broken; just report, don't clean up */ - WARN(1, "error: irq_desc already assigned to a domain"); - return; + domain = kzalloc(sizeof(*domain), GFP_KERNEL); + if (WARN_ON(!domain)) + return NULL; + + /* Fill structure */ + domain->revmap_type = revmap_type; + domain->ops = ops; + domain->host_data = host_data; + domain->of_node = of_node_get(of_node); + + return domain; +} + +static void irq_domain_add(struct irq_domain *domain) +{ + mutex_lock(&irq_domain_mutex); + list_add(&domain->link, &irq_domain_list); + mutex_unlock(&irq_domain_mutex); + pr_debug("irq: Allocated domain of type %d @0x%p\n", + domain->revmap_type, domain); +} + +static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain, + irq_hw_number_t hwirq) +{ + irq_hw_number_t first_hwirq = domain->revmap_data.legacy.first_hwirq; + int size = domain->revmap_data.legacy.size; + + if (WARN_ON(hwirq < first_hwirq || hwirq >= first_hwirq + size)) + return 0; + return hwirq - first_hwirq + domain->revmap_data.legacy.first_irq; +} + +/** + * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain. + * @of_node: pointer to interrupt controller's device tree node. + * @size: total number of irqs in legacy mapping + * @first_irq: first number of irq block assigned to the domain + * @first_hwirq: first hwirq number to use for the translation. Should normally + * be '0', but a positive integer can be used if the effective + * hwirqs numbering does not begin at zero. + * @ops: map/unmap domain callbacks + * @host_data: Controller private data pointer + * + * Note: the map() callback will be called before this function returns + * for all legacy interrupts except 0 (which is always the invalid irq for + * a legacy controller). + */ +struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, + unsigned int size, + unsigned int first_irq, + irq_hw_number_t first_hwirq, + const struct irq_domain_ops *ops, + void *host_data) +{ + struct irq_domain *domain; + unsigned int i; + + domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LEGACY, ops, host_data); + if (!domain) + return NULL; + + domain->revmap_data.legacy.first_irq = first_irq; + domain->revmap_data.legacy.first_hwirq = first_hwirq; + domain->revmap_data.legacy.size = size; + + mutex_lock(&irq_domain_mutex); + /* Verify that all the irqs are available */ + for (i = 0; i < size; i++) { + int irq = first_irq + i; + struct irq_data *irq_data = irq_get_irq_data(irq); + + if (WARN_ON(!irq_data || irq_data->domain)) { + mutex_unlock(&irq_domain_mutex); + of_node_put(domain->of_node); + kfree(domain); + return NULL; } - d->domain = domain; - d->hwirq = hwirq; } - mutex_lock(&irq_domain_mutex); - list_add(&domain->list, &irq_domain_list); + /* Claim all of the irqs before registering a legacy domain */ + for (i = 0; i < size; i++) { + struct irq_data *irq_data = irq_get_irq_data(first_irq + i); + irq_data->hwirq = first_hwirq + i; + irq_data->domain = domain; + } mutex_unlock(&irq_domain_mutex); + + for (i = 0; i < size; i++) { + int irq = first_irq + i; + int hwirq = first_hwirq + i; + + /* IRQ0 gets ignored */ + if (!irq) + continue; + + /* Legacy flags are left to default at this point, + * one can then use irq_create_mapping() to + * explicitly change them + */ + ops->map(domain, irq, hwirq); + + /* Clear norequest flags */ + irq_clear_status_flags(irq, IRQ_NOREQUEST); + } + + irq_domain_add(domain); + return domain; +} + +/** + * irq_domain_add_linear() - Allocate and register a legacy revmap irq_domain. + * @of_node: pointer to interrupt controller's device tree node. + * @ops: map/unmap domain callbacks + * @host_data: Controller private data pointer + */ +struct irq_domain *irq_domain_add_linear(struct device_node *of_node, + unsigned int size, + const struct irq_domain_ops *ops, + void *host_data) +{ + struct irq_domain *domain; + unsigned int *revmap; + + revmap = kzalloc(sizeof(*revmap) * size, GFP_KERNEL); + if (WARN_ON(!revmap)) + return NULL; + + domain = irq_domain_alloc(of_node, IRQ_DOMAIN_MAP_LINEAR, ops, host_data); + if (!domain) { + kfree(revmap); + return NULL; + } + domain->revmap_data.linear.size = size; + domain->revmap_data.linear.revmap = revmap; + irq_domain_add(domain); + return domain; +} + +struct irq_domain *irq_domain_add_nomap(struct device_node *of_node, + const struct irq_domain_ops *ops, + void *host_data) +{ + struct irq_domain *domain = irq_domain_alloc(of_node, + IRQ_DOMAIN_MAP_NOMAP, ops, host_data); + if (domain) + irq_domain_add(domain); + return domain; +} + +/** + * irq_domain_add_tree() + * @of_node: pointer to interrupt controller's device tree node. + * @ops: map/unmap domain callbacks + * + * Note: The radix tree will be allocated later during boot automatically + * (the reverse mapping will use the slow path until that happens). + */ +struct irq_domain *irq_domain_add_tree(struct device_node *of_node, + const struct irq_domain_ops *ops, + void *host_data) +{ + struct irq_domain *domain = irq_domain_alloc(of_node, + IRQ_DOMAIN_MAP_TREE, ops, host_data); + if (domain) { + INIT_RADIX_TREE(&domain->revmap_data.tree, GFP_KERNEL); + irq_domain_add(domain); + } + return domain; } /** - * irq_domain_del() - Unregister an irq_domain - * @domain: ptr to registered irq_domain. + * irq_find_host() - Locates a domain for a given device node + * @node: device-tree node of the interrupt controller */ -void irq_domain_del(struct irq_domain *domain) +struct irq_domain *irq_find_host(struct device_node *node) { - struct irq_data *d; - int hwirq, irq; + struct irq_domain *h, *found = NULL; + int rc; + /* We might want to match the legacy controller last since + * it might potentially be set to match all interrupts in + * the absence of a device node. This isn't a problem so far + * yet though... + */ mutex_lock(&irq_domain_mutex); - list_del(&domain->list); + list_for_each_entry(h, &irq_domain_list, link) { + if (h->ops->match) + rc = h->ops->match(h, node); + else + rc = (h->of_node != NULL) && (h->of_node == node); + + if (rc) { + found = h; + break; + } + } mutex_unlock(&irq_domain_mutex); + return found; +} +EXPORT_SYMBOL_GPL(irq_find_host); + +/** + * irq_set_default_host() - Set a "default" irq domain + * @domain: default domain pointer + * + * For convenience, it's possible to set a "default" domain that will be used + * whenever NULL is passed to irq_create_mapping(). It makes life easier for + * platforms that want to manipulate a few hard coded interrupt numbers that + * aren't properly represented in the device-tree. + */ +void irq_set_default_host(struct irq_domain *domain) +{ + pr_debug("irq: Default domain set to @0x%p\n", domain); + + irq_default_domain = domain; +} + +/** + * irq_set_virq_count() - Set the maximum number of linux irqs + * @count: number of linux irqs, capped with NR_IRQS + * + * This is mainly for use by platforms like iSeries who want to program + * the virtual irq number in the controller to avoid the reverse mapping + */ +void irq_set_virq_count(unsigned int count) +{ + pr_debug("irq: Trying to set virq count to %d\n", count); - /* Clear the irq_domain assignments */ - irq_domain_for_each_irq(domain, hwirq, irq) { - d = irq_get_irq_data(irq); - d->domain = NULL; + BUG_ON(count < NUM_ISA_INTERRUPTS); + if (count < NR_IRQS) + irq_virq_count = count; +} + +static int irq_setup_virq(struct irq_domain *domain, unsigned int virq, + irq_hw_number_t hwirq) +{ + struct irq_data *irq_data = irq_get_irq_data(virq); + + irq_data->hwirq = hwirq; + irq_data->domain = domain; + if (domain->ops->map(domain, virq, hwirq)) { + pr_debug("irq: -> mapping failed, freeing\n"); + irq_data->domain = NULL; + irq_data->hwirq = 0; + return -1; } + + irq_clear_status_flags(virq, IRQ_NOREQUEST); + + return 0; } -#if defined(CONFIG_OF_IRQ) /** - * irq_create_of_mapping() - Map a linux irq number from a DT interrupt spec + * irq_create_direct_mapping() - Allocate an irq for direct mapping + * @domain: domain to allocate the irq for or NULL for default domain * - * Used by the device tree interrupt mapping code to translate a device tree - * interrupt specifier to a valid linux irq number. Returns either a valid - * linux IRQ number or 0. + * This routine is used for irq controllers which can choose the hardware + * interrupt numbers they generate. In such a case it's simplest to use + * the linux irq as the hardware interrupt number. + */ +unsigned int irq_create_direct_mapping(struct irq_domain *domain) +{ + unsigned int virq; + + if (domain == NULL) + domain = irq_default_domain; + + BUG_ON(domain == NULL); + WARN_ON(domain->revmap_type != IRQ_DOMAIN_MAP_NOMAP); + + virq = irq_alloc_desc_from(1, 0); + if (!virq) { + pr_debug("irq: create_direct virq allocation failed\n"); + return 0; + } + if (virq >= irq_virq_count) { + pr_err("ERROR: no free irqs available below %i maximum\n", + irq_virq_count); + irq_free_desc(virq); + return 0; + } + + pr_debug("irq: create_direct obtained virq %d\n", virq); + + if (irq_setup_virq(domain, virq, virq)) { + irq_free_desc(virq); + return 0; + } + + return virq; +} + +/** + * irq_create_mapping() - Map a hardware interrupt into linux irq space + * @domain: domain owning this hardware interrupt or NULL for default domain + * @hwirq: hardware irq number in that domain space * - * When the caller no longer need the irq number returned by this function it - * should arrange to call irq_dispose_mapping(). + * Only one mapping per hardware interrupt is permitted. Returns a linux + * irq number. + * If the sense/trigger is to be specified, set_irq_type() should be called + * on the number returned from that call. */ +unsigned int irq_create_mapping(struct irq_domain *domain, + irq_hw_number_t hwirq) +{ + unsigned int virq, hint; + + pr_debug("irq: irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq); + + /* Look for default domain if nececssary */ + if (domain == NULL) + domain = irq_default_domain; + if (domain == NULL) { + printk(KERN_WARNING "irq_create_mapping called for" + " NULL domain, hwirq=%lx\n", hwirq); + WARN_ON(1); + return 0; + } + pr_debug("irq: -> using domain @%p\n", domain); + + /* Check if mapping already exists */ + virq = irq_find_mapping(domain, hwirq); + if (virq) { + pr_debug("irq: -> existing mapping on virq %d\n", virq); + return virq; + } + + /* Get a virtual interrupt number */ + if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY) + return irq_domain_legacy_revmap(domain, hwirq); + + /* Allocate a virtual interrupt number */ + hint = hwirq % irq_virq_count; + if (hint == 0) + hint++; + virq = irq_alloc_desc_from(hint, 0); + if (!virq) + virq = irq_alloc_desc_from(1, 0); + if (!virq) { + pr_debug("irq: -> virq allocation failed\n"); + return 0; + } + + if (irq_setup_virq(domain, virq, hwirq)) { + if (domain->revmap_type != IRQ_DOMAIN_MAP_LEGACY) + irq_free_desc(virq); + return 0; + } + + pr_debug("irq: irq %lu on domain %s mapped to virtual irq %u\n", + hwirq, domain->of_node ? domain->of_node->full_name : "null", virq); + + return virq; +} +EXPORT_SYMBOL_GPL(irq_create_mapping); + unsigned int irq_create_of_mapping(struct device_node *controller, const u32 *intspec, unsigned int intsize) { struct irq_domain *domain; - unsigned long hwirq; - unsigned int irq, type; - int rc = -EINVAL; + irq_hw_number_t hwirq; + unsigned int type = IRQ_TYPE_NONE; + unsigned int virq; - /* Find a domain which can translate the irq spec */ - mutex_lock(&irq_domain_mutex); - list_for_each_entry(domain, &irq_domain_list, list) { - if (!domain->ops->dt_translate) - continue; - rc = domain->ops->dt_translate(domain, controller, - intspec, intsize, &hwirq, &type); - if (rc == 0) - break; + domain = controller ? irq_find_host(controller) : irq_default_domain; + if (!domain) { +#ifdef CONFIG_MIPS + /* + * Workaround to avoid breaking interrupt controller drivers + * that don't yet register an irq_domain. This is temporary + * code. ~~~gcl, Feb 24, 2012 + * + * Scheduled for removal in Linux v3.6. That should be enough + * time. + */ + if (intsize > 0) + return intspec[0]; +#endif + printk(KERN_WARNING "irq: no irq domain found for %s !\n", + controller->full_name); + return 0; } - mutex_unlock(&irq_domain_mutex); - if (rc != 0) - return 0; + /* If domain has no translation, then we assume interrupt line */ + if (domain->ops->xlate == NULL) + hwirq = intspec[0]; + else { + if (domain->ops->xlate(domain, controller, intspec, intsize, + &hwirq, &type)) + return 0; + } + + /* Create mapping */ + virq = irq_create_mapping(domain, hwirq); + if (!virq) + return virq; - irq = irq_domain_to_irq(domain, hwirq); - if (type != IRQ_TYPE_NONE) - irq_set_irq_type(irq, type); - pr_debug("%s: mapped hwirq=%i to irq=%i, flags=%x\n", - controller->full_name, (int)hwirq, irq, type); - return irq; + /* Set type if specified and different than the current one */ + if (type != IRQ_TYPE_NONE && + type != (irqd_get_trigger_type(irq_get_irq_data(virq)))) + irq_set_irq_type(virq, type); + return virq; } EXPORT_SYMBOL_GPL(irq_create_of_mapping); /** - * irq_dispose_mapping() - Discard a mapping created by irq_create_of_mapping() - * @irq: linux irq number to be discarded + * irq_dispose_mapping() - Unmap an interrupt + * @virq: linux irq number of the interrupt to unmap + */ +void irq_dispose_mapping(unsigned int virq) +{ + struct irq_data *irq_data = irq_get_irq_data(virq); + struct irq_domain *domain; + irq_hw_number_t hwirq; + + if (!virq || !irq_data) + return; + + domain = irq_data->domain; + if (WARN_ON(domain == NULL)) + return; + + /* Never unmap legacy interrupts */ + if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY) + return; + + irq_set_status_flags(virq, IRQ_NOREQUEST); + + /* remove chip and handler */ + irq_set_chip_and_handler(virq, NULL, NULL); + + /* Make sure it's completed */ + synchronize_irq(virq); + + /* Tell the PIC about it */ + if (domain->ops->unmap) + domain->ops->unmap(domain, virq); + smp_mb(); + + /* Clear reverse map */ + hwirq = irq_data->hwirq; + switch(domain->revmap_type) { + case IRQ_DOMAIN_MAP_LINEAR: + if (hwirq < domain->revmap_data.linear.size) + domain->revmap_data.linear.revmap[hwirq] = 0; + break; + case IRQ_DOMAIN_MAP_TREE: + mutex_lock(&revmap_trees_mutex); + radix_tree_delete(&domain->revmap_data.tree, hwirq); + mutex_unlock(&revmap_trees_mutex); + break; + } + + irq_free_desc(virq); +} +EXPORT_SYMBOL_GPL(irq_dispose_mapping); + +/** + * irq_find_mapping() - Find a linux irq from an hw irq number. + * @domain: domain owning this hardware interrupt + * @hwirq: hardware irq number in that domain space + * + * This is a slow path, for use by generic code. It's expected that an + * irq controller implementation directly calls the appropriate low level + * mapping function. + */ +unsigned int irq_find_mapping(struct irq_domain *domain, + irq_hw_number_t hwirq) +{ + unsigned int i; + unsigned int hint = hwirq % irq_virq_count; + + /* Look for default domain if nececssary */ + if (domain == NULL) + domain = irq_default_domain; + if (domain == NULL) + return 0; + + /* legacy -> bail early */ + if (domain->revmap_type == IRQ_DOMAIN_MAP_LEGACY) + return irq_domain_legacy_revmap(domain, hwirq); + + /* Slow path does a linear search of the map */ + if (hint == 0) + hint = 1; + i = hint; + do { + struct irq_data *data = irq_get_irq_data(i); + if (data && (data->domain == domain) && (data->hwirq == hwirq)) + return i; + i++; + if (i >= irq_virq_count) + i = 1; + } while(i != hint); + return 0; +} +EXPORT_SYMBOL_GPL(irq_find_mapping); + +/** + * irq_radix_revmap_lookup() - Find a linux irq from a hw irq number. + * @domain: domain owning this hardware interrupt + * @hwirq: hardware irq number in that domain space * - * Calling this function indicates the caller no longer needs a reference to - * the linux irq number returned by a prior call to irq_create_of_mapping(). + * This is a fast path, for use by irq controller code that uses radix tree + * revmaps */ -void irq_dispose_mapping(unsigned int irq) +unsigned int irq_radix_revmap_lookup(struct irq_domain *domain, + irq_hw_number_t hwirq) { + struct irq_data *irq_data; + + if (WARN_ON_ONCE(domain->revmap_type != IRQ_DOMAIN_MAP_TREE)) + return irq_find_mapping(domain, hwirq); + + /* + * Freeing an irq can delete nodes along the path to + * do the lookup via call_rcu. + */ + rcu_read_lock(); + irq_data = radix_tree_lookup(&domain->revmap_data.tree, hwirq); + rcu_read_unlock(); + /* - * nothing yet; will be filled when support for dynamic allocation of - * irq_descs is added to irq_domain + * If found in radix tree, then fine. + * Else fallback to linear lookup - this should not happen in practice + * as it means that we failed to insert the node in the radix tree. */ + return irq_data ? irq_data->irq : irq_find_mapping(domain, hwirq); } -EXPORT_SYMBOL_GPL(irq_dispose_mapping); -int irq_domain_simple_dt_translate(struct irq_domain *d, - struct device_node *controller, - const u32 *intspec, unsigned int intsize, - unsigned long *out_hwirq, unsigned int *out_type) +/** + * irq_radix_revmap_insert() - Insert a hw irq to linux irq number mapping. + * @domain: domain owning this hardware interrupt + * @virq: linux irq number + * @hwirq: hardware irq number in that domain space + * + * This is for use by irq controllers that use a radix tree reverse + * mapping for fast lookup. + */ +void irq_radix_revmap_insert(struct irq_domain *domain, unsigned int virq, + irq_hw_number_t hwirq) { - if (d->of_node != controller) - return -EINVAL; - if (intsize < 1) - return -EINVAL; - if (d->nr_irq && ((intspec[0] < d->hwirq_base) || - (intspec[0] >= d->hwirq_base + d->nr_irq))) - return -EINVAL; + struct irq_data *irq_data = irq_get_irq_data(virq); + + if (WARN_ON(domain->revmap_type != IRQ_DOMAIN_MAP_TREE)) + return; + + if (virq) { + mutex_lock(&revmap_trees_mutex); + radix_tree_insert(&domain->revmap_data.tree, hwirq, irq_data); + mutex_unlock(&revmap_trees_mutex); + } +} + +/** + * irq_linear_revmap() - Find a linux irq from a hw irq number. + * @domain: domain owning this hardware interrupt + * @hwirq: hardware irq number in that domain space + * + * This is a fast path, for use by irq controller code that uses linear + * revmaps. It does fallback to the slow path if the revmap doesn't exist + * yet and will create the revmap entry with appropriate locking + */ +unsigned int irq_linear_revmap(struct irq_domain *domain, + irq_hw_number_t hwirq) +{ + unsigned int *revmap; + + if (WARN_ON_ONCE(domain->revmap_type != IRQ_DOMAIN_MAP_LINEAR)) + return irq_find_mapping(domain, hwirq); + + /* Check revmap bounds */ + if (unlikely(hwirq >= domain->revmap_data.linear.size)) + return irq_find_mapping(domain, hwirq); + + /* Check if revmap was allocated */ + revmap = domain->revmap_data.linear.revmap; + if (unlikely(revmap == NULL)) + return irq_find_mapping(domain, hwirq); + + /* Fill up revmap with slow path if no mapping found */ + if (unlikely(!revmap[hwirq])) + revmap[hwirq] = irq_find_mapping(domain, hwirq); + + return revmap[hwirq]; +} + +#ifdef CONFIG_IRQ_DOMAIN_DEBUG +static int virq_debug_show(struct seq_file *m, void *private) +{ + unsigned long flags; + struct irq_desc *desc; + const char *p; + static const char none[] = "none"; + void *data; + int i; + + seq_printf(m, "%-5s %-7s %-15s %-18s %s\n", "virq", "hwirq", + "chip name", "chip data", "domain name"); + + for (i = 1; i < nr_irqs; i++) { + desc = irq_to_desc(i); + if (!desc) + continue; + + raw_spin_lock_irqsave(&desc->lock, flags); + + if (desc->action && desc->action->handler) { + struct irq_chip *chip; + + seq_printf(m, "%5d ", i); + seq_printf(m, "0x%05lx ", desc->irq_data.hwirq); + + chip = irq_desc_get_chip(desc); + if (chip && chip->name) + p = chip->name; + else + p = none; + seq_printf(m, "%-15s ", p); + + data = irq_desc_get_chip_data(desc); + seq_printf(m, "0x%16p ", data); + + if (desc->irq_data.domain && desc->irq_data.domain->of_node) + p = desc->irq_data.domain->of_node->full_name; + else + p = none; + seq_printf(m, "%s\n", p); + } + + raw_spin_unlock_irqrestore(&desc->lock, flags); + } + + return 0; +} +static int virq_debug_open(struct inode *inode, struct file *file) +{ + return single_open(file, virq_debug_show, inode->i_private); +} + +static const struct file_operations virq_debug_fops = { + .open = virq_debug_open, + .read = seq_read, + .llseek = seq_lseek, + .release = single_release, +}; + +static int __init irq_debugfs_init(void) +{ + if (debugfs_create_file("irq_domain_mapping", S_IRUGO, NULL, + NULL, &virq_debug_fops) == NULL) + return -ENOMEM; + + return 0; +} +__initcall(irq_debugfs_init); +#endif /* CONFIG_IRQ_DOMAIN_DEBUG */ + +int irq_domain_simple_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) +{ + return 0; +} + +/** + * irq_domain_xlate_onecell() - Generic xlate for direct one cell bindings + * + * Device Tree IRQ specifier translation function which works with one cell + * bindings where the cell value maps directly to the hwirq number. + */ +int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + if (WARN_ON(intsize < 1)) + return -EINVAL; *out_hwirq = intspec[0]; *out_type = IRQ_TYPE_NONE; - if (intsize > 1) - *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK; return 0; } +EXPORT_SYMBOL_GPL(irq_domain_xlate_onecell); /** - * irq_domain_create_simple() - Set up a 'simple' translation range + * irq_domain_xlate_twocell() - Generic xlate for direct two cell bindings + * + * Device Tree IRQ specifier translation function which works with two cell + * bindings where the cell values map directly to the hwirq number + * and linux irq flags. */ -void irq_domain_add_simple(struct device_node *controller, int irq_base) +int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr, + const u32 *intspec, unsigned int intsize, + irq_hw_number_t *out_hwirq, unsigned int *out_type) { - struct irq_domain *domain; - - domain = kzalloc(sizeof(*domain), GFP_KERNEL); - if (!domain) { - WARN_ON(1); - return; - } + if (WARN_ON(intsize < 2)) + return -EINVAL; + *out_hwirq = intspec[0]; + *out_type = intspec[1] & IRQ_TYPE_SENSE_MASK; + return 0; +} +EXPORT_SYMBOL_GPL(irq_domain_xlate_twocell); - domain->irq_base = irq_base; - domain->of_node = of_node_get(controller); - domain->ops = &irq_domain_simple_ops; - irq_domain_add(domain); +/** + * irq_domain_xlate_onetwocell() - Generic xlate for one or two cell bindings + * + * Device Tree IRQ specifier translation function which works with either one + * or two cell bindings where the cell values map directly to the hwirq number + * and linux irq flags. + * + * Note: don't use this function unless your interrupt controller explicitly + * supports both one and two cell bindings. For the majority of controllers + * the _onecell() or _twocell() variants above should be used. + */ +int irq_domain_xlate_onetwocell(struct irq_domain *d, + struct device_node *ctrlr, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type) +{ + if (WARN_ON(intsize < 1)) + return -EINVAL; + *out_hwirq = intspec[0]; + *out_type = (intsize > 1) ? intspec[1] : IRQ_TYPE_NONE; + return 0; } -EXPORT_SYMBOL_GPL(irq_domain_add_simple); +EXPORT_SYMBOL_GPL(irq_domain_xlate_onetwocell); +const struct irq_domain_ops irq_domain_simple_ops = { + .map = irq_domain_simple_map, + .xlate = irq_domain_xlate_onetwocell, +}; +EXPORT_SYMBOL_GPL(irq_domain_simple_ops); + +#ifdef CONFIG_OF_IRQ void irq_domain_generate_simple(const struct of_device_id *match, u64 phys_base, unsigned int irq_start) { struct device_node *node; - pr_info("looking for phys_base=%llx, irq_start=%i\n", + pr_debug("looking for phys_base=%llx, irq_start=%i\n", (unsigned long long) phys_base, (int) irq_start); node = of_find_matching_node_by_address(NULL, match, phys_base); if (node) - irq_domain_add_simple(node, irq_start); - else - pr_info("no node found\n"); + irq_domain_add_legacy(node, 32, irq_start, 0, + &irq_domain_simple_ops, NULL); } EXPORT_SYMBOL_GPL(irq_domain_generate_simple); -#endif /* CONFIG_OF_IRQ */ - -struct irq_domain_ops irq_domain_simple_ops = { -#ifdef CONFIG_OF_IRQ - .dt_translate = irq_domain_simple_dt_translate, -#endif /* CONFIG_OF_IRQ */ -}; -EXPORT_SYMBOL_GPL(irq_domain_simple_ops); +#endif diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index a9a9dbe49fea..b0ccd1ac2d6a 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -759,6 +759,13 @@ static irqreturn_t irq_thread_fn(struct irq_desc *desc, return ret; } +static void wake_threads_waitq(struct irq_desc *desc) +{ + if (atomic_dec_and_test(&desc->threads_active) && + waitqueue_active(&desc->wait_for_threads)) + wake_up(&desc->wait_for_threads); +} + /* * Interrupt handler thread */ @@ -771,57 +778,41 @@ static int irq_thread(void *data) struct irq_desc *desc = irq_to_desc(action->irq); irqreturn_t (*handler_fn)(struct irq_desc *desc, struct irqaction *action); - int wake; - if (force_irqthreads & test_bit(IRQTF_FORCED_THREAD, + if (force_irqthreads && test_bit(IRQTF_FORCED_THREAD, &action->thread_flags)) handler_fn = irq_forced_thread_fn; else handler_fn = irq_thread_fn; sched_setscheduler(current, SCHED_FIFO, ¶m); - current->irqaction = action; + current->irq_thread = 1; while (!irq_wait_for_interrupt(action)) { + irqreturn_t action_ret; irq_thread_check_affinity(desc, action); - atomic_inc(&desc->threads_active); - - raw_spin_lock_irq(&desc->lock); - if (unlikely(irqd_irq_disabled(&desc->irq_data))) { - /* - * CHECKME: We might need a dedicated - * IRQ_THREAD_PENDING flag here, which - * retriggers the thread in check_irq_resend() - * but AFAICT IRQS_PENDING should be fine as it - * retriggers the interrupt itself --- tglx - */ - desc->istate |= IRQS_PENDING; - raw_spin_unlock_irq(&desc->lock); - } else { - irqreturn_t action_ret; - - raw_spin_unlock_irq(&desc->lock); - action_ret = handler_fn(desc, action); - if (!noirqdebug) - note_interrupt(action->irq, desc, action_ret); - } + action_ret = handler_fn(desc, action); + if (!noirqdebug) + note_interrupt(action->irq, desc, action_ret); - wake = atomic_dec_and_test(&desc->threads_active); - - if (wake && waitqueue_active(&desc->wait_for_threads)) - wake_up(&desc->wait_for_threads); + wake_threads_waitq(desc); } - /* Prevent a stale desc->threads_oneshot */ - irq_finalize_oneshot(desc, action, true); - /* - * Clear irqaction. Otherwise exit_irq_thread() would make + * This is the regular exit path. __free_irq() is stopping the + * thread via kthread_stop() after calling + * synchronize_irq(). So neither IRQTF_RUNTHREAD nor the + * oneshot mask bit can be set. We cannot verify that as we + * cannot touch the oneshot mask at this point anymore as + * __setup_irq() might have given out currents thread_mask + * again. + * + * Clear irq_thread. Otherwise exit_irq_thread() would make * fuzz about an active irq thread going into nirvana. */ - current->irqaction = NULL; + current->irq_thread = 0; return 0; } @@ -832,27 +823,28 @@ void exit_irq_thread(void) { struct task_struct *tsk = current; struct irq_desc *desc; + struct irqaction *action; - if (!tsk->irqaction) + if (!tsk->irq_thread) return; + action = kthread_data(tsk); + printk(KERN_ERR "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n", - tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq); + tsk->comm ? tsk->comm : "", tsk->pid, action->irq); - desc = irq_to_desc(tsk->irqaction->irq); + desc = irq_to_desc(action->irq); /* - * Prevent a stale desc->threads_oneshot. Must be called - * before setting the IRQTF_DIED flag. + * If IRQTF_RUNTHREAD is set, we need to decrement + * desc->threads_active and wake possible waiters. */ - irq_finalize_oneshot(desc, tsk->irqaction, true); + if (test_and_clear_bit(IRQTF_RUNTHREAD, &action->thread_flags)) + wake_threads_waitq(desc); - /* - * Set the THREAD DIED flag to prevent further wakeups of the - * soon to be gone threaded handler. - */ - set_bit(IRQTF_DIED, &tsk->irqaction->flags); + /* Prevent a stale desc->threads_oneshot */ + irq_finalize_oneshot(desc, action, true); } static void irq_setup_forced_threading(struct irqaction *new) @@ -985,6 +977,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) /* add new interrupt at end of irq queue */ do { + /* + * Or all existing action->thread_mask bits, + * so we can find the next zero bit for this + * new action. + */ thread_mask |= old->thread_mask; old_ptr = &old->next; old = *old_ptr; @@ -993,14 +990,41 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) } /* - * Setup the thread mask for this irqaction. Unlikely to have - * 32 resp 64 irqs sharing one line, but who knows. + * Setup the thread mask for this irqaction for ONESHOT. For + * !ONESHOT irqs the thread mask is 0 so we can avoid a + * conditional in irq_wake_thread(). */ - if (new->flags & IRQF_ONESHOT && thread_mask == ~0UL) { - ret = -EBUSY; - goto out_mask; + if (new->flags & IRQF_ONESHOT) { + /* + * Unlikely to have 32 resp 64 irqs sharing one line, + * but who knows. + */ + if (thread_mask == ~0UL) { + ret = -EBUSY; + goto out_mask; + } + /* + * The thread_mask for the action is or'ed to + * desc->thread_active to indicate that the + * IRQF_ONESHOT thread handler has been woken, but not + * yet finished. The bit is cleared when a thread + * completes. When all threads of a shared interrupt + * line have completed desc->threads_active becomes + * zero and the interrupt line is unmasked. See + * handle.c:irq_wake_thread() for further information. + * + * If no thread is woken by primary (hard irq context) + * interrupt handlers, then desc->threads_active is + * also checked for zero to unmask the irq line in the + * affected hard irq flow handlers + * (handle_[fasteoi|level]_irq). + * + * The new action gets the first zero bit of + * thread_mask assigned. See the loop above which or's + * all existing action->thread_mask bits. + */ + new->thread_mask = 1 << ffz(thread_mask); } - new->thread_mask = 1 << ffz(thread_mask); if (!shared) { init_waitqueue_head(&desc->wait_for_threads); @@ -1027,7 +1051,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) desc->istate |= IRQS_ONESHOT; if (irq_settings_can_autoenable(desc)) - irq_startup(desc); + irq_startup(desc, true); else /* Undo nested disables: */ desc->depth = 1; @@ -1103,8 +1127,7 @@ out_thread: struct task_struct *t = new->thread; new->thread = NULL; - if (likely(!test_bit(IRQTF_DIED, &new->thread_flags))) - kthread_stop(t); + kthread_stop(t); put_task_struct(t); } out_mput: @@ -1214,8 +1237,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) #endif if (action->thread) { - if (!test_bit(IRQTF_DIED, &action->thread_flags)) - kthread_stop(action->thread); + kthread_stop(action->thread); put_task_struct(action->thread); } |