1 /*
2 * irq_domain - IRQ translation domains
3 *
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.
7 *
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.
11 *
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.
19 *
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
29 * controllers.
30 */
31
32 #ifndef _LINUX_IRQDOMAIN_H
33 #define _LINUX_IRQDOMAIN_H
34
35 #include <linux/types.h>
36 #include <linux/radix-tree.h>
37
38 struct device_node;
39 struct irq_domain;
40 struct of_device_id;
41
42 /* Number of irqs reserved for a legacy isa controller */
43 #define NUM_ISA_INTERRUPTS 16
44
45 /**
46 * struct irq_domain_ops - Methods for irq_domain objects
47 * @match: Match an interrupt controller device node to a host, returns
48 * 1 on a match
49 * @map: Create or update a mapping between a virtual irq number and a hw
50 * irq number. This is called only once for a given mapping.
51 * @unmap: Dispose of such a mapping
52 * @xlate: Given a device tree node and interrupt specifier, decode
53 * the hardware irq number and linux irq type value.
54 *
55 * Functions below are provided by the driver and called whenever a new mapping
56 * is created or an old mapping is disposed. The driver can then proceed to
57 * whatever internal data structures management is required. It also needs
58 * to setup the irq_desc when returning from map().
59 */
60 struct irq_domain_ops {
61 int (*match)(struct irq_domain *d, struct device_node *node);
62 int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
63 void (*unmap)(struct irq_domain *d, unsigned int virq);
64 int (*xlate)(struct irq_domain *d, struct device_node *node,
65 const u32 *intspec, unsigned int intsize,
66 unsigned long *out_hwirq, unsigned int *out_type);
67 };
68
69 /**
70 * struct irq_domain - Hardware interrupt number translation object
71 * @link: Element in global irq_domain list.
72 * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
73 * will be one of the IRQ_DOMAIN_MAP_* values.
74 * @revmap_data: Revmap method specific data.
75 * @ops: pointer to irq_domain methods
76 * @host_data: private data pointer for use by owner. Not touched by irq_domain
77 * core code.
78 * @irq_base: Start of irq_desc range assigned to the irq_domain. The creator
79 * of the irq_domain is responsible for allocating the array of
80 * irq_desc structures.
81 * @nr_irq: Number of irqs managed by the irq domain
82 * @hwirq_base: Starting number for hwirqs managed by the irq domain
83 * @of_node: (optional) Pointer to device tree nodes associated with the
84 * irq_domain. Used when decoding device tree interrupt specifiers.
85 */
86 struct irq_domain {
87 struct list_head link;
88
89 /* type of reverse mapping_technique */
90 unsigned int revmap_type;
91 union {
92 struct {
93 unsigned int size;
94 unsigned int first_irq;
95 irq_hw_number_t first_hwirq;
96 } legacy;
97 struct {
98 unsigned int size;
99 unsigned int *revmap;
100 } linear;
101 struct {
102 unsigned int max_irq;
103 } nomap;
104 struct radix_tree_root tree;
105 } revmap_data;
106 const struct irq_domain_ops *ops;
107 void *host_data;
108 irq_hw_number_t inval_irq;
109
110 /* Optional device node pointer */
111 struct device_node *of_node;
112 };
113
114 #ifdef CONFIG_IRQ_DOMAIN
115 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
116 unsigned int size,
117 unsigned int first_irq,
118 irq_hw_number_t first_hwirq,
119 const struct irq_domain_ops *ops,
120 void *host_data);
121 struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
122 unsigned int size,
123 const struct irq_domain_ops *ops,
124 void *host_data);
125 struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
126 unsigned int max_irq,
127 const struct irq_domain_ops *ops,
128 void *host_data);
129 struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
130 const struct irq_domain_ops *ops,
131 void *host_data);
132
133 extern struct irq_domain *irq_find_host(struct device_node *node);
134 extern void irq_set_default_host(struct irq_domain *host);
135
irq_domain_add_legacy_isa(struct device_node * of_node,const struct irq_domain_ops * ops,void * host_data)136 static inline struct irq_domain *irq_domain_add_legacy_isa(
137 struct device_node *of_node,
138 const struct irq_domain_ops *ops,
139 void *host_data)
140 {
141 return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
142 host_data);
143 }
144 extern struct irq_domain *irq_find_host(struct device_node *node);
145 extern void irq_set_default_host(struct irq_domain *host);
146
147
148 extern unsigned int irq_create_mapping(struct irq_domain *host,
149 irq_hw_number_t hwirq);
150 extern void irq_dispose_mapping(unsigned int virq);
151 extern unsigned int irq_find_mapping(struct irq_domain *host,
152 irq_hw_number_t hwirq);
153 extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
154 extern void irq_radix_revmap_insert(struct irq_domain *host, unsigned int virq,
155 irq_hw_number_t hwirq);
156 extern unsigned int irq_radix_revmap_lookup(struct irq_domain *host,
157 irq_hw_number_t hwirq);
158 extern unsigned int irq_linear_revmap(struct irq_domain *host,
159 irq_hw_number_t hwirq);
160
161 extern const struct irq_domain_ops irq_domain_simple_ops;
162
163 /* stock xlate functions */
164 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
165 const u32 *intspec, unsigned int intsize,
166 irq_hw_number_t *out_hwirq, unsigned int *out_type);
167 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
168 const u32 *intspec, unsigned int intsize,
169 irq_hw_number_t *out_hwirq, unsigned int *out_type);
170 int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
171 const u32 *intspec, unsigned int intsize,
172 irq_hw_number_t *out_hwirq, unsigned int *out_type);
173
174 #if defined(CONFIG_OF_IRQ)
175 extern void irq_domain_generate_simple(const struct of_device_id *match,
176 u64 phys_base, unsigned int irq_start);
177 #else /* CONFIG_OF_IRQ */
irq_domain_generate_simple(const struct of_device_id * match,u64 phys_base,unsigned int irq_start)178 static inline void irq_domain_generate_simple(const struct of_device_id *match,
179 u64 phys_base, unsigned int irq_start) { }
180 #endif /* !CONFIG_OF_IRQ */
181
182 #else /* CONFIG_IRQ_DOMAIN */
irq_dispose_mapping(unsigned int virq)183 static inline void irq_dispose_mapping(unsigned int virq) { }
184 #endif /* !CONFIG_IRQ_DOMAIN */
185
186 #endif /* _LINUX_IRQDOMAIN_H */
187