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.
20 * The host code and data structures are agnostic to whether or not
21 * we use an open firmware device-tree. We do have references to struct
22 * device_node in two places: in irq_find_host() to find the host matching
23 * a given interrupt controller node, and of course as an argument to its
24 * counterpart domain->ops->match() callback. However, those are treated as
25 * generic pointers by the core and the fact that it's actually a device-node
26 * pointer is purely a convention between callers and implementation. This
27 * code could thus be used on other architectures by replacing those two
28 * by some sort of arch-specific void * "token" used to identify interrupt
32 #ifndef _LINUX_IRQDOMAIN_H
33 #define _LINUX_IRQDOMAIN_H
35 #include <linux/types.h>
36 #include <linux/radix-tree.h>
42 /* This type is the placeholder for a hardware interrupt number. It has to
43 * be big enough to enclose whatever representation is used by a given
46 typedef unsigned long irq_hw_number_t;
49 * struct irq_domain_ops - Methods for irq_domain objects
50 * @match: Match an interrupt controller device node to a host, returns
52 * @map: Create or update a mapping between a virtual irq number and a hw
53 * irq number. This is called only once for a given mapping.
54 * @unmap: Dispose of such a mapping
55 * @to_irq: (optional) given a local hardware irq number, return the linux
56 * irq number. If to_irq is not implemented, then the irq_domain
57 * will use this translation: irq = (domain->irq_base + hwirq)
58 * @xlate: Given a device tree node and interrupt specifier, decode
59 * the hardware irq number and linux irq type value.
61 * Functions below are provided by the driver and called whenever a new mapping
62 * is created or an old mapping is disposed. The driver can then proceed to
63 * whatever internal data structures management is required. It also needs
64 * to setup the irq_desc when returning from map().
66 struct irq_domain_ops {
67 int (*match)(struct irq_domain *d, struct device_node *node);
68 int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
69 void (*unmap)(struct irq_domain *d, unsigned int virq);
70 unsigned int (*to_irq)(struct irq_domain *d, unsigned long hwirq);
71 int (*xlate)(struct irq_domain *d, struct device_node *node,
72 const u32 *intspec, unsigned int intsize,
73 unsigned long *out_hwirq, unsigned int *out_type);
77 * struct irq_domain - Hardware interrupt number translation object
78 * @link: Element in global irq_domain list.
79 * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
80 * will be one of the IRQ_DOMAIN_MAP_* values.
81 * @revmap_data: Revmap method specific data.
82 * @ops: pointer to irq_domain methods
83 * @host_data: private data pointer for use by owner. Not touched by irq_domain
85 * @irq_base: Start of irq_desc range assigned to the irq_domain. The creator
86 * of the irq_domain is responsible for allocating the array of
87 * irq_desc structures.
88 * @nr_irq: Number of irqs managed by the irq domain
89 * @hwirq_base: Starting number for hwirqs managed by the irq domain
90 * @of_node: (optional) Pointer to device tree nodes associated with the
91 * irq_domain. Used when decoding device tree interrupt specifiers.
94 struct list_head link;
96 /* type of reverse mapping_technique */
97 unsigned int revmap_type;
101 unsigned int *revmap;
103 struct radix_tree_root tree;
105 struct irq_domain_ops *ops;
107 irq_hw_number_t inval_irq;
109 unsigned int irq_base;
111 unsigned int hwirq_base;
113 /* Optional device node pointer */
114 struct device_node *of_node;
117 #ifdef CONFIG_IRQ_DOMAIN
119 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
120 struct irq_domain_ops *ops,
122 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
124 struct irq_domain_ops *ops,
126 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
127 struct irq_domain_ops *ops,
129 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
130 struct irq_domain_ops *ops,
134 extern struct irq_domain *irq_find_host(struct device_node *node);
135 extern void irq_set_default_host(struct irq_domain *host);
136 extern void irq_set_virq_count(unsigned int count);
139 extern unsigned int irq_create_mapping(struct irq_domain *host,
140 irq_hw_number_t hwirq);
141 extern void irq_dispose_mapping(unsigned int virq);
142 extern unsigned int irq_find_mapping(struct irq_domain *host,
143 irq_hw_number_t hwirq);
144 extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
145 extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
146 irq_hw_number_t hwirq);
147 extern unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
148 irq_hw_number_t hwirq);
149 extern unsigned int irq_linear_revmap(struct irq_domain *host,
150 irq_hw_number_t hwirq);
152 #else /* CONFIG_PPC */
155 * irq_domain_to_irq() - Translate from a hardware irq to a linux irq number
157 * Returns the linux irq number associated with a hardware irq. By default,
158 * the mapping is irq == domain->irq_base + hwirq, but this mapping can
159 * be overridden if the irq_domain implements a .to_irq() hook.
161 static inline unsigned int irq_domain_to_irq(struct irq_domain *d,
165 return d->ops->to_irq(d, hwirq);
166 if (WARN_ON(hwirq < d->hwirq_base))
168 return d->irq_base + hwirq - d->hwirq_base;
171 #define irq_domain_for_each_hwirq(d, hw) \
172 for (hw = d->hwirq_base; hw < d->hwirq_base + d->nr_irq; hw++)
174 #define irq_domain_for_each_irq(d, hw, irq) \
175 for (hw = d->hwirq_base, irq = irq_domain_to_irq(d, hw); \
176 hw < d->hwirq_base + d->nr_irq; \
177 hw++, irq = irq_domain_to_irq(d, hw))
179 extern void irq_domain_add(struct irq_domain *domain);
180 extern void irq_domain_del(struct irq_domain *domain);
182 extern struct irq_domain_ops irq_domain_simple_ops;
184 #if defined(CONFIG_OF_IRQ)
185 extern void irq_domain_add_simple(struct device_node *controller, int irq_base);
186 extern void irq_domain_generate_simple(const struct of_device_id *match,
187 u64 phys_base, unsigned int irq_start);
188 #else /* CONFIG_OF_IRQ */
189 static inline void irq_domain_generate_simple(const struct of_device_id *match,
190 u64 phys_base, unsigned int irq_start) { }
191 #endif /* !CONFIG_OF_IRQ */
192 #endif /* !CONFIG_PPC */
193 #endif /* CONFIG_IRQ_DOMAIN */
195 #endif /* _LINUX_IRQDOMAIN_H */