xref: /openbmc/linux/include/linux/irqdomain.h (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
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/irqhandler.h>
37 #include <linux/radix-tree.h>
38 
39 struct device_node;
40 struct irq_domain;
41 struct of_device_id;
42 struct irq_chip;
43 struct irq_data;
44 
45 /* Number of irqs reserved for a legacy isa controller */
46 #define NUM_ISA_INTERRUPTS	16
47 
48 /*
49  * Should several domains have the same device node, but serve
50  * different purposes (for example one domain is for PCI/MSI, and the
51  * other for wired IRQs), they can be distinguished using a
52  * bus-specific token. Most domains are expected to only carry
53  * DOMAIN_BUS_ANY.
54  */
55 enum irq_domain_bus_token {
56 	DOMAIN_BUS_ANY		= 0,
57 	DOMAIN_BUS_PCI_MSI,
58 	DOMAIN_BUS_PLATFORM_MSI,
59 	DOMAIN_BUS_NEXUS,
60 };
61 
62 /**
63  * struct irq_domain_ops - Methods for irq_domain objects
64  * @match: Match an interrupt controller device node to a host, returns
65  *         1 on a match
66  * @map: Create or update a mapping between a virtual irq number and a hw
67  *       irq number. This is called only once for a given mapping.
68  * @unmap: Dispose of such a mapping
69  * @xlate: Given a device tree node and interrupt specifier, decode
70  *         the hardware irq number and linux irq type value.
71  *
72  * Functions below are provided by the driver and called whenever a new mapping
73  * is created or an old mapping is disposed. The driver can then proceed to
74  * whatever internal data structures management is required. It also needs
75  * to setup the irq_desc when returning from map().
76  */
77 struct irq_domain_ops {
78 	int (*match)(struct irq_domain *d, struct device_node *node,
79 		     enum irq_domain_bus_token bus_token);
80 	int (*map)(struct irq_domain *d, unsigned int virq, irq_hw_number_t hw);
81 	void (*unmap)(struct irq_domain *d, unsigned int virq);
82 	int (*xlate)(struct irq_domain *d, struct device_node *node,
83 		     const u32 *intspec, unsigned int intsize,
84 		     unsigned long *out_hwirq, unsigned int *out_type);
85 
86 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
87 	/* extended V2 interfaces to support hierarchy irq_domains */
88 	int (*alloc)(struct irq_domain *d, unsigned int virq,
89 		     unsigned int nr_irqs, void *arg);
90 	void (*free)(struct irq_domain *d, unsigned int virq,
91 		     unsigned int nr_irqs);
92 	void (*activate)(struct irq_domain *d, struct irq_data *irq_data);
93 	void (*deactivate)(struct irq_domain *d, struct irq_data *irq_data);
94 #endif
95 };
96 
97 extern struct irq_domain_ops irq_generic_chip_ops;
98 
99 struct irq_domain_chip_generic;
100 
101 /**
102  * struct irq_domain - Hardware interrupt number translation object
103  * @link: Element in global irq_domain list.
104  * @name: Name of interrupt domain
105  * @ops: pointer to irq_domain methods
106  * @host_data: private data pointer for use by owner.  Not touched by irq_domain
107  *             core code.
108  * @flags: host per irq_domain flags
109  *
110  * Optional elements
111  * @of_node: Pointer to device tree nodes associated with the irq_domain. Used
112  *           when decoding device tree interrupt specifiers.
113  * @gc: Pointer to a list of generic chips. There is a helper function for
114  *      setting up one or more generic chips for interrupt controllers
115  *      drivers using the generic chip library which uses this pointer.
116  * @parent: Pointer to parent irq_domain to support hierarchy irq_domains
117  *
118  * Revmap data, used internally by irq_domain
119  * @revmap_direct_max_irq: The largest hwirq that can be set for controllers that
120  *                         support direct mapping
121  * @revmap_size: Size of the linear map table @linear_revmap[]
122  * @revmap_tree: Radix map tree for hwirqs that don't fit in the linear map
123  * @linear_revmap: Linear table of hwirq->virq reverse mappings
124  */
125 struct irq_domain {
126 	struct list_head link;
127 	const char *name;
128 	const struct irq_domain_ops *ops;
129 	void *host_data;
130 	unsigned int flags;
131 
132 	/* Optional data */
133 	struct device_node *of_node;
134 	enum irq_domain_bus_token bus_token;
135 	struct irq_domain_chip_generic *gc;
136 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
137 	struct irq_domain *parent;
138 #endif
139 
140 	/* reverse map data. The linear map gets appended to the irq_domain */
141 	irq_hw_number_t hwirq_max;
142 	unsigned int revmap_direct_max_irq;
143 	unsigned int revmap_size;
144 	struct radix_tree_root revmap_tree;
145 	unsigned int linear_revmap[];
146 };
147 
148 /* Irq domain flags */
149 enum {
150 	/* Irq domain is hierarchical */
151 	IRQ_DOMAIN_FLAG_HIERARCHY	= (1 << 0),
152 
153 	/* Core calls alloc/free recursive through the domain hierarchy. */
154 	IRQ_DOMAIN_FLAG_AUTO_RECURSIVE	= (1 << 1),
155 
156 	/*
157 	 * Flags starting from IRQ_DOMAIN_FLAG_NONCORE are reserved
158 	 * for implementation specific purposes and ignored by the
159 	 * core code.
160 	 */
161 	IRQ_DOMAIN_FLAG_NONCORE		= (1 << 16),
162 };
163 
164 static inline struct device_node *irq_domain_get_of_node(struct irq_domain *d)
165 {
166 	return d->of_node;
167 }
168 
169 #ifdef CONFIG_IRQ_DOMAIN
170 struct irq_domain *__irq_domain_add(struct device_node *of_node, int size,
171 				    irq_hw_number_t hwirq_max, int direct_max,
172 				    const struct irq_domain_ops *ops,
173 				    void *host_data);
174 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
175 					 unsigned int size,
176 					 unsigned int first_irq,
177 					 const struct irq_domain_ops *ops,
178 					 void *host_data);
179 struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
180 					 unsigned int size,
181 					 unsigned int first_irq,
182 					 irq_hw_number_t first_hwirq,
183 					 const struct irq_domain_ops *ops,
184 					 void *host_data);
185 extern struct irq_domain *irq_find_matching_host(struct device_node *node,
186 						 enum irq_domain_bus_token bus_token);
187 extern void irq_set_default_host(struct irq_domain *host);
188 
189 static inline struct irq_domain *irq_find_host(struct device_node *node)
190 {
191 	return irq_find_matching_host(node, DOMAIN_BUS_ANY);
192 }
193 
194 /**
195  * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
196  * @of_node: pointer to interrupt controller's device tree node.
197  * @size: Number of interrupts in the domain.
198  * @ops: map/unmap domain callbacks
199  * @host_data: Controller private data pointer
200  */
201 static inline struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
202 					 unsigned int size,
203 					 const struct irq_domain_ops *ops,
204 					 void *host_data)
205 {
206 	return __irq_domain_add(of_node, size, size, 0, ops, host_data);
207 }
208 static inline struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
209 					 unsigned int max_irq,
210 					 const struct irq_domain_ops *ops,
211 					 void *host_data)
212 {
213 	return __irq_domain_add(of_node, 0, max_irq, max_irq, ops, host_data);
214 }
215 static inline struct irq_domain *irq_domain_add_legacy_isa(
216 				struct device_node *of_node,
217 				const struct irq_domain_ops *ops,
218 				void *host_data)
219 {
220 	return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,
221 				     host_data);
222 }
223 static inline struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
224 					 const struct irq_domain_ops *ops,
225 					 void *host_data)
226 {
227 	return __irq_domain_add(of_node, 0, ~0, 0, ops, host_data);
228 }
229 
230 extern void irq_domain_remove(struct irq_domain *host);
231 
232 extern int irq_domain_associate(struct irq_domain *domain, unsigned int irq,
233 					irq_hw_number_t hwirq);
234 extern void irq_domain_associate_many(struct irq_domain *domain,
235 				      unsigned int irq_base,
236 				      irq_hw_number_t hwirq_base, int count);
237 extern void irq_domain_disassociate(struct irq_domain *domain,
238 				    unsigned int irq);
239 
240 extern unsigned int irq_create_mapping(struct irq_domain *host,
241 				       irq_hw_number_t hwirq);
242 extern void irq_dispose_mapping(unsigned int virq);
243 
244 /**
245  * irq_linear_revmap() - Find a linux irq from a hw irq number.
246  * @domain: domain owning this hardware interrupt
247  * @hwirq: hardware irq number in that domain space
248  *
249  * This is a fast path alternative to irq_find_mapping() that can be
250  * called directly by irq controller code to save a handful of
251  * instructions. It is always safe to call, but won't find irqs mapped
252  * using the radix tree.
253  */
254 static inline unsigned int irq_linear_revmap(struct irq_domain *domain,
255 					     irq_hw_number_t hwirq)
256 {
257 	return hwirq < domain->revmap_size ? domain->linear_revmap[hwirq] : 0;
258 }
259 extern unsigned int irq_find_mapping(struct irq_domain *host,
260 				     irq_hw_number_t hwirq);
261 extern unsigned int irq_create_direct_mapping(struct irq_domain *host);
262 extern int irq_create_strict_mappings(struct irq_domain *domain,
263 				      unsigned int irq_base,
264 				      irq_hw_number_t hwirq_base, int count);
265 
266 static inline int irq_create_identity_mapping(struct irq_domain *host,
267 					      irq_hw_number_t hwirq)
268 {
269 	return irq_create_strict_mappings(host, hwirq, hwirq, 1);
270 }
271 
272 extern const struct irq_domain_ops irq_domain_simple_ops;
273 
274 /* stock xlate functions */
275 int irq_domain_xlate_onecell(struct irq_domain *d, struct device_node *ctrlr,
276 			const u32 *intspec, unsigned int intsize,
277 			irq_hw_number_t *out_hwirq, unsigned int *out_type);
278 int irq_domain_xlate_twocell(struct irq_domain *d, struct device_node *ctrlr,
279 			const u32 *intspec, unsigned int intsize,
280 			irq_hw_number_t *out_hwirq, unsigned int *out_type);
281 int irq_domain_xlate_onetwocell(struct irq_domain *d, struct device_node *ctrlr,
282 			const u32 *intspec, unsigned int intsize,
283 			irq_hw_number_t *out_hwirq, unsigned int *out_type);
284 
285 /* V2 interfaces to support hierarchy IRQ domains. */
286 extern struct irq_data *irq_domain_get_irq_data(struct irq_domain *domain,
287 						unsigned int virq);
288 extern void irq_domain_set_info(struct irq_domain *domain, unsigned int virq,
289 				irq_hw_number_t hwirq, struct irq_chip *chip,
290 				void *chip_data, irq_flow_handler_t handler,
291 				void *handler_data, const char *handler_name);
292 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
293 extern struct irq_domain *irq_domain_add_hierarchy(struct irq_domain *parent,
294 			unsigned int flags, unsigned int size,
295 			struct device_node *node,
296 			const struct irq_domain_ops *ops, void *host_data);
297 extern int __irq_domain_alloc_irqs(struct irq_domain *domain, int irq_base,
298 				   unsigned int nr_irqs, int node, void *arg,
299 				   bool realloc);
300 extern void irq_domain_free_irqs(unsigned int virq, unsigned int nr_irqs);
301 extern void irq_domain_activate_irq(struct irq_data *irq_data);
302 extern void irq_domain_deactivate_irq(struct irq_data *irq_data);
303 
304 static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
305 			unsigned int nr_irqs, int node, void *arg)
306 {
307 	return __irq_domain_alloc_irqs(domain, -1, nr_irqs, node, arg, false);
308 }
309 
310 extern int irq_domain_set_hwirq_and_chip(struct irq_domain *domain,
311 					 unsigned int virq,
312 					 irq_hw_number_t hwirq,
313 					 struct irq_chip *chip,
314 					 void *chip_data);
315 extern void irq_domain_reset_irq_data(struct irq_data *irq_data);
316 extern void irq_domain_free_irqs_common(struct irq_domain *domain,
317 					unsigned int virq,
318 					unsigned int nr_irqs);
319 extern void irq_domain_free_irqs_top(struct irq_domain *domain,
320 				     unsigned int virq, unsigned int nr_irqs);
321 
322 extern int irq_domain_alloc_irqs_parent(struct irq_domain *domain,
323 					unsigned int irq_base,
324 					unsigned int nr_irqs, void *arg);
325 
326 extern void irq_domain_free_irqs_parent(struct irq_domain *domain,
327 					unsigned int irq_base,
328 					unsigned int nr_irqs);
329 
330 static inline bool irq_domain_is_hierarchy(struct irq_domain *domain)
331 {
332 	return domain->flags & IRQ_DOMAIN_FLAG_HIERARCHY;
333 }
334 #else	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
335 static inline void irq_domain_activate_irq(struct irq_data *data) { }
336 static inline void irq_domain_deactivate_irq(struct irq_data *data) { }
337 static inline int irq_domain_alloc_irqs(struct irq_domain *domain,
338 			unsigned int nr_irqs, int node, void *arg)
339 {
340 	return -1;
341 }
342 
343 static inline bool irq_domain_is_hierarchy(struct irq_domain *domain)
344 {
345 	return false;
346 }
347 #endif	/* CONFIG_IRQ_DOMAIN_HIERARCHY */
348 
349 #else /* CONFIG_IRQ_DOMAIN */
350 static inline void irq_dispose_mapping(unsigned int virq) { }
351 static inline void irq_domain_activate_irq(struct irq_data *data) { }
352 static inline void irq_domain_deactivate_irq(struct irq_data *data) { }
353 #endif /* !CONFIG_IRQ_DOMAIN */
354 
355 #endif /* _LINUX_IRQDOMAIN_H */
356