diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 1478c6171b00..8ac7b996038c 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1682,6 +1682,7 @@ config USE_OF bool "Flattened Device Tree support" select OF select OF_EARLY_FLATTREE + select IRQ_DOMAIN help Include support for flattened device tree machine descriptions. diff --git a/arch/arm/include/asm/prom.h b/arch/arm/include/asm/prom.h index 11b8708fc4db..6f65ca86a5ec 100644 --- a/arch/arm/include/asm/prom.h +++ b/arch/arm/include/asm/prom.h @@ -16,11 +16,6 @@ #include #include -static inline void irq_dispose_mapping(unsigned int virq) -{ - return; -} - extern struct machine_desc *setup_machine_fdt(unsigned int dt_phys); extern void arm_dt_memblock_reserve(void); diff --git a/arch/arm/kernel/devtree.c b/arch/arm/kernel/devtree.c index 0cdd7b456cb2..1a33e9d6bb1f 100644 --- a/arch/arm/kernel/devtree.c +++ b/arch/arm/kernel/devtree.c @@ -132,17 +132,3 @@ struct machine_desc * __init setup_machine_fdt(unsigned int dt_phys) return mdesc_best; } - -/** - * irq_create_of_mapping - Hook to resolve OF irq specifier into a Linux irq# - * - * Currently the mapping mechanism is trivial; simple flat hwirq numbers are - * mapped 1:1 onto Linux irq numbers. Cascaded irq controllers are not - * supported. - */ -unsigned int irq_create_of_mapping(struct device_node *controller, - const u32 *intspec, unsigned int intsize) -{ - return intspec[0]; -} -EXPORT_SYMBOL_GPL(irq_create_of_mapping); diff --git a/include/linux/irq.h b/include/linux/irq.h index 5f695041090c..87a06f345bd2 100644 --- a/include/linux/irq.h +++ b/include/linux/irq.h @@ -108,14 +108,18 @@ enum { }; struct msi_desc; +struct irq_domain; /** * struct irq_data - per irq and irq chip data passed down to chip functions * @irq: interrupt number + * @hwirq: hardware interrupt number, local to the interrupt domain * @node: node index useful for balancing * @state_use_accessors: status information for irq chip functions. * Use accessor functions to deal with it * @chip: low level interrupt hardware access + * @domain: Interrupt translation domain; responsible for mapping + * between hwirq number and linux irq number. * @handler_data: per-IRQ data for the irq_chip methods * @chip_data: platform-specific per-chip private data for the chip * methods, to allow shared chip implementations @@ -128,9 +132,11 @@ struct msi_desc; */ struct irq_data { unsigned int irq; + unsigned long hwirq; unsigned int node; unsigned int state_use_accessors; struct irq_chip *chip; + struct irq_domain *domain; void *handler_data; void *chip_data; struct msi_desc *msi_desc; diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h new file mode 100644 index 000000000000..8f2c10a784a4 --- /dev/null +++ b/include/linux/irqdomain.h @@ -0,0 +1,81 @@ +/* + * irq_domain - IRQ translation domains + * + * Translation infrastructure between hw and linux irq numbers. This is + * helpful for interrupt controllers to implement mapping between hardware + * irq numbers and the Linux irq number space. + * + * irq_domains also have a hook for translating device tree interrupt + * representation into a hardware irq number that can be mapped back to a + * Linux irq number without any extra platform support code. + * + * irq_domain is expected to be embedded in an interrupt controller's private + * data structure. + */ +#ifndef _LINUX_IRQDOMAIN_H +#define _LINUX_IRQDOMAIN_H + +#include + +#ifdef CONFIG_IRQ_DOMAIN +struct device_node; +struct irq_domain; + +/** + * struct irq_domain_ops - Methods for irq_domain objects + * @to_irq: (optional) given a local hardware irq number, return the linux + * irq number. If to_irq is not implemented, then the irq_domain + * will use this translation: irq = (domain->irq_base + hwirq) + * @dt_translate: Given a device tree node and interrupt specifier, decode + * the hardware irq number and linux irq type value. + */ +struct irq_domain_ops { + unsigned int (*to_irq)(struct irq_domain *d, unsigned long hwirq); + +#ifdef CONFIG_OF + int (*dt_translate)(struct irq_domain *d, struct device_node *node, + const u32 *intspec, unsigned int intsize, + unsigned long *out_hwirq, unsigned int *out_type); +#endif /* CONFIG_OF */ +}; + +/** + * struct irq_domain - Hardware interrupt number translation object + * @list: Element in global irq_domain list. + * @irq_base: Start of irq_desc range assigned to the irq_domain. The creator + * of the irq_domain is responsible for allocating the array of + * irq_desc structures. + * @nr_irq: Number of irqs managed by the irq domain + * @ops: pointer to irq_domain methods + * @priv: private data pointer for use by owner. Not touched by irq_domain + * core code. + * @of_node: (optional) Pointer to device tree nodes associated with the + * irq_domain. Used when decoding device tree interrupt specifiers. + */ +struct irq_domain { + struct list_head list; + unsigned int irq_base; + unsigned int nr_irq; + const struct irq_domain_ops *ops; + void *priv; + struct device_node *of_node; +}; + +/** + * irq_domain_to_irq() - Translate from a hardware irq to a linux irq number + * + * Returns the linux irq number associated with a hardware irq. By default, + * the mapping is irq == domain->irq_base + hwirq, but this mapping can + * be overridden if the irq_domain implements a .to_irq() hook. + */ +static inline unsigned int irq_domain_to_irq(struct irq_domain *d, + unsigned long hwirq) +{ + return d->ops->to_irq ? d->ops->to_irq(d, hwirq) : d->irq_base + hwirq; +} + +extern void irq_domain_add(struct irq_domain *domain); +extern void irq_domain_del(struct irq_domain *domain); +#endif /* CONFIG_IRQ_DOMAIN */ + +#endif /* _LINUX_IRQDOMAIN_H */ diff --git a/include/linux/of_irq.h b/include/linux/of_irq.h index e6955f5d1f08..cd2e61ce4e83 100644 --- a/include/linux/of_irq.h +++ b/include/linux/of_irq.h @@ -63,6 +63,9 @@ extern int of_irq_map_one(struct device_node *device, int index, extern unsigned int irq_create_of_mapping(struct device_node *controller, const u32 *intspec, unsigned int intsize); +#ifdef CONFIG_IRQ_DOMAIN +extern void irq_dispose_mapping(unsigned int irq); +#endif extern int of_irq_to_resource(struct device_node *dev, int index, struct resource *r); extern int of_irq_count(struct device_node *dev); @@ -70,6 +73,7 @@ extern int of_irq_to_resource_table(struct device_node *dev, struct resource *res, int nr_irqs); extern struct device_node *of_irq_find_parent(struct device_node *child); + #endif /* CONFIG_OF_IRQ */ #endif /* CONFIG_OF */ #endif /* __OF_IRQ_H */ diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index d1d051b38e0b..5a38bf4de641 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -52,6 +52,10 @@ config IRQ_EDGE_EOI_HANDLER config GENERIC_IRQ_CHIP bool +# Generic irq_domain hw <--> linux irq number translation +config IRQ_DOMAIN + bool + # Support forced irq threading config IRQ_FORCED_THREADING bool diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile index 73290056cfb6..fff17381f0af 100644 --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -2,6 +2,7 @@ obj-y := irqdesc.o handle.o manage.o spurious.o resend.o chip.o dummychip.o devres.o obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o +obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o obj-$(CONFIG_PM_SLEEP) += pm.o diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c new file mode 100644 index 000000000000..29c7bd42e25d --- /dev/null +++ b/kernel/irq/irqdomain.c @@ -0,0 +1,122 @@ +#include +#include +#include +#include +#include + +static LIST_HEAD(irq_domain_list); +static DEFINE_MUTEX(irq_domain_mutex); + +/** + * irq_domain_add() - Register an irq_domain + * @domain: ptr to initialized irq_domain structure + * + * 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. + */ +void irq_domain_add(struct irq_domain *domain) +{ + struct irq_data *d; + int hwirq; + + /* + * 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. + */ + for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) { + d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq)); + if (d || d->domain) { + /* things are broken; just report, don't clean up */ + WARN(1, "error: irq_desc already assigned to a domain"); + return; + } + d->domain = domain; + d->hwirq = hwirq; + } + + mutex_lock(&irq_domain_mutex); + list_add(&domain->list, &irq_domain_list); + mutex_unlock(&irq_domain_mutex); +} + +/** + * irq_domain_del() - Unregister an irq_domain + * @domain: ptr to registered irq_domain. + */ +void irq_domain_del(struct irq_domain *domain) +{ + struct irq_data *d; + int hwirq; + + mutex_lock(&irq_domain_mutex); + list_del(&domain->list); + mutex_unlock(&irq_domain_mutex); + + /* Clear the irq_domain assignments */ + for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) { + d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq)); + d->domain = NULL; + } +} + +#if defined(CONFIG_OF_IRQ) +/** + * irq_create_of_mapping() - Map a linux irq number from a DT interrupt spec + * + * 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. + * + * When the caller no longer need the irq number returned by this function it + * should arrange to call irq_dispose_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; + + /* 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; + } + mutex_unlock(&irq_domain_mutex); + + if (rc != 0) + return 0; + + 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; +} +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 + * + * 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(). + */ +void irq_dispose_mapping(unsigned int irq) +{ + /* + * nothing yet; will be filled when support for dynamic allocation of + * irq_descs is added to irq_domain + */ +} +EXPORT_SYMBOL_GPL(irq_dispose_mapping); +#endif /* CONFIG_OF_IRQ */