2 * irq_domain - IRQ translation domains
4 * Translation infrastructure between hw and linux irq numbers. This is
5 * helpful for interrupt controllers to implement mapping between hardware
6 * irq numbers and the Linux irq number space.
8 * irq_domains also have a hook for translating device tree interrupt
9 * representation into a hardware irq number that can be mapped back to a
10 * Linux irq number without any extra platform support code.
12 * Interrupt controller "domain" data structure. This could be defined as a
13 * irq domain controller. That is, it handles the mapping between hardware
14 * and virtual interrupt numbers for a given interrupt domain. The domain
15 * structure is generally created by the PIC code for a given PIC instance
16 * (though a domain can cover more than one PIC if they have a flat number
17 * model). It's the domain callbacks that are responsible for setting the
18 * irq_chip on a given irq_desc after it's been mapped.
21 #ifndef _LINUX_IRQDOMAIN_H
22 #define _LINUX_IRQDOMAIN_H
24 #include <linux/types.h>
25 #include <linux/radix-tree.h>
31 /* This type is the placeholder for a hardware interrupt number. It has to
32 * be big enough to enclose whatever representation is used by a given
35 typedef unsigned long irq_hw_number_t;
38 * struct irq_domain_ops - Methods for irq_domain objects
39 * @match: Match an interrupt controller device node to a host, returns
41 * @map: Create or update a mapping between a virtual irq number and a hw
42 * irq number. This is called only once for a given mapping.
43 * @unmap: Dispose of such a mapping
44 * @to_irq: (optional) given a local hardware irq number, return the linux
45 * irq number. If to_irq is not implemented, then the irq_domain
46 * will use this translation: irq = (domain->irq_base + hwirq)
47 * @xlate: Given a device tree node and interrupt specifier, decode
48 * the hardware irq number and linux irq type value.
50 * Functions below are provided by the driver and called whenever a new mapping
51 * is created or an old mapping is disposed. The driver can then proceed to
52 * whatever internal data structures management is required. It also needs
53 * to setup the irq_desc when returning from map().
55 struct irq_domain_ops {
56 int (*match)(struct irq_domain *d, struct device_node *node);
57 int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
58 void (*unmap)(struct irq_domain *d, unsigned int virq);
59 unsigned int (*to_irq)(struct irq_domain *d, unsigned long hwirq);
60 int (*xlate)(struct irq_domain *d, struct device_node *node,
61 const u32 *intspec, unsigned int intsize,
62 unsigned long *out_hwirq, unsigned int *out_type);
66 * struct irq_domain - Hardware interrupt number translation object
67 * @link: Element in global irq_domain list.
68 * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
69 * will be one of the IRQ_DOMAIN_MAP_* values.
70 * @revmap_data: Revmap method specific data.
71 * @ops: pointer to irq_domain methods
72 * @host_data: private data pointer for use by owner. Not touched by irq_domain
74 * @irq_base: Start of irq_desc range assigned to the irq_domain. The creator
75 * of the irq_domain is responsible for allocating the array of
76 * irq_desc structures.
77 * @nr_irq: Number of irqs managed by the irq domain
78 * @hwirq_base: Starting number for hwirqs managed by the irq domain
79 * @of_node: (optional) Pointer to device tree nodes associated with the
80 * irq_domain. Used when decoding device tree interrupt specifiers.
83 struct list_head link;
85 /* type of reverse mapping_technique */
86 unsigned int revmap_type;
87 #define IRQ_DOMAIN_MAP_LEGACY 0 /* legacy 8259, gets irqs 1..15 */
88 #define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */
89 #define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */
90 #define IRQ_DOMAIN_MAP_TREE 3 /* radix tree */
96 struct radix_tree_root tree;
98 struct irq_domain_ops *ops;
100 irq_hw_number_t inval_irq;
102 unsigned int irq_base;
104 unsigned int hwirq_base;
106 /* Optional device node pointer */
107 struct device_node *of_node;
110 #ifdef CONFIG_IRQ_DOMAIN
112 * irq_domain_to_irq() - Translate from a hardware irq to a linux irq number
114 * Returns the linux irq number associated with a hardware irq. By default,
115 * the mapping is irq == domain->irq_base + hwirq, but this mapping can
116 * be overridden if the irq_domain implements a .to_irq() hook.
118 static inline unsigned int irq_domain_to_irq(struct irq_domain *d,
122 return d->ops->to_irq(d, hwirq);
123 if (WARN_ON(hwirq < d->hwirq_base))
125 return d->irq_base + hwirq - d->hwirq_base;
128 #define irq_domain_for_each_hwirq(d, hw) \
129 for (hw = d->hwirq_base; hw < d->hwirq_base + d->nr_irq; hw++)
131 #define irq_domain_for_each_irq(d, hw, irq) \
132 for (hw = d->hwirq_base, irq = irq_domain_to_irq(d, hw); \
133 hw < d->hwirq_base + d->nr_irq; \
134 hw++, irq = irq_domain_to_irq(d, hw))
136 extern void irq_domain_add(struct irq_domain *domain);
137 extern void irq_domain_del(struct irq_domain *domain);
139 extern struct irq_domain_ops irq_domain_simple_ops;
140 #endif /* CONFIG_IRQ_DOMAIN */
142 #if defined(CONFIG_IRQ_DOMAIN) && defined(CONFIG_OF_IRQ)
143 extern void irq_domain_add_simple(struct device_node *controller, int irq_base);
144 extern void irq_domain_generate_simple(const struct of_device_id *match,
145 u64 phys_base, unsigned int irq_start);
146 #else /* CONFIG_IRQ_DOMAIN && CONFIG_OF_IRQ */
147 static inline void irq_domain_generate_simple(const struct of_device_id *match,
148 u64 phys_base, unsigned int irq_start) { }
149 #endif /* CONFIG_IRQ_DOMAIN && CONFIG_OF_IRQ */
151 #endif /* _LINUX_IRQDOMAIN_H */