1 #ifdef __KERNEL__
2 #ifndef _ASM_POWERPC_IRQ_H
3 #define _ASM_POWERPC_IRQ_H
4
5 /*
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12 #include <linux/threads.h>
13 #include <linux/list.h>
14 #include <linux/radix-tree.h>
15
16 #include <asm/types.h>
17 #include <asm/atomic.h>
18
19
20 #define get_irq_desc(irq) (&irq_desc[(irq)])
21
22 /* Define a way to iterate across irqs. */
23 #define for_each_irq(i) \
24 for ((i) = 0; (i) < NR_IRQS; ++(i))
25
26 extern atomic_t ppc_n_lost_interrupts;
27
28 /* This number is used when no interrupt has been assigned */
29 #define NO_IRQ (0)
30
31 /* This is a special irq number to return from get_irq() to tell that
32 * no interrupt happened _and_ ignore it (don't count it as bad). Some
33 * platforms like iSeries rely on that.
34 */
35 #define NO_IRQ_IGNORE ((unsigned int)-1)
36
37 /* Total number of virq in the platform (make it a CONFIG_* option ? */
38 #define NR_IRQS 512
39
40 /* Number of irqs reserved for the legacy controller */
41 #define NUM_ISA_INTERRUPTS 16
42
43 /* This type is the placeholder for a hardware interrupt number. It has to
44 * be big enough to enclose whatever representation is used by a given
45 * platform.
46 */
47 typedef unsigned long irq_hw_number_t;
48
49 /* Interrupt controller "host" data structure. This could be defined as a
50 * irq domain controller. That is, it handles the mapping between hardware
51 * and virtual interrupt numbers for a given interrupt domain. The host
52 * structure is generally created by the PIC code for a given PIC instance
53 * (though a host can cover more than one PIC if they have a flat number
54 * model). It's the host callbacks that are responsible for setting the
55 * irq_chip on a given irq_desc after it's been mapped.
56 *
57 * The host code and data structures are fairly agnostic to the fact that
58 * we use an open firmware device-tree. We do have references to struct
59 * device_node in two places: in irq_find_host() to find the host matching
60 * a given interrupt controller node, and of course as an argument to its
61 * counterpart host->ops->match() callback. However, those are treated as
62 * generic pointers by the core and the fact that it's actually a device-node
63 * pointer is purely a convention between callers and implementation. This
64 * code could thus be used on other architectures by replacing those two
65 * by some sort of arch-specific void * "token" used to identify interrupt
66 * controllers.
67 */
68 struct irq_host;
69 struct radix_tree_root;
70
71 /* Functions below are provided by the host and called whenever a new mapping
72 * is created or an old mapping is disposed. The host can then proceed to
73 * whatever internal data structures management is required. It also needs
74 * to setup the irq_desc when returning from map().
75 */
76 struct irq_host_ops {
77 /* Match an interrupt controller device node to a host, returns
78 * 1 on a match
79 */
80 int (*match)(struct irq_host *h, struct device_node *node);
81
82 /* Create or update a mapping between a virtual irq number and a hw
83 * irq number. This is called only once for a given mapping.
84 */
85 int (*map)(struct irq_host *h, unsigned int virq, irq_hw_number_t hw);
86
87 /* Dispose of such a mapping */
88 void (*unmap)(struct irq_host *h, unsigned int virq);
89
90 /* Update of such a mapping */
91 void (*remap)(struct irq_host *h, unsigned int virq, irq_hw_number_t hw);
92
93 /* Translate device-tree interrupt specifier from raw format coming
94 * from the firmware to a irq_hw_number_t (interrupt line number) and
95 * type (sense) that can be passed to set_irq_type(). In the absence
96 * of this callback, irq_create_of_mapping() and irq_of_parse_and_map()
97 * will return the hw number in the first cell and IRQ_TYPE_NONE for
98 * the type (which amount to keeping whatever default value the
99 * interrupt controller has for that line)
100 */
101 int (*xlate)(struct irq_host *h, struct device_node *ctrler,
102 u32 *intspec, unsigned int intsize,
103 irq_hw_number_t *out_hwirq, unsigned int *out_type);
104 };
105
106 struct irq_host {
107 struct list_head link;
108
109 /* type of reverse mapping technique */
110 unsigned int revmap_type;
111 #define IRQ_HOST_MAP_LEGACY 0 /* legacy 8259, gets irqs 1..15 */
112 #define IRQ_HOST_MAP_NOMAP 1 /* no fast reverse mapping */
113 #define IRQ_HOST_MAP_LINEAR 2 /* linear map of interrupts */
114 #define IRQ_HOST_MAP_TREE 3 /* radix tree */
115 union {
116 struct {
117 unsigned int size;
118 unsigned int *revmap;
119 } linear;
120 struct radix_tree_root tree;
121 } revmap_data;
122 struct irq_host_ops *ops;
123 void *host_data;
124 irq_hw_number_t inval_irq;
125
126 /* Optional device node pointer */
127 struct device_node *of_node;
128 };
129
130 /* The main irq map itself is an array of NR_IRQ entries containing the
131 * associate host and irq number. An entry with a host of NULL is free.
132 * An entry can be allocated if it's free, the allocator always then sets
133 * hwirq first to the host's invalid irq number and then fills ops.
134 */
135 struct irq_map_entry {
136 irq_hw_number_t hwirq;
137 struct irq_host *host;
138 };
139
140 extern struct irq_map_entry irq_map[NR_IRQS];
141
142 extern irq_hw_number_t virq_to_hw(unsigned int virq);
143
144 /**
145 * irq_alloc_host - Allocate a new irq_host data structure
146 * @of_node: optional device-tree node of the interrupt controller
147 * @revmap_type: type of reverse mapping to use
148 * @revmap_arg: for IRQ_HOST_MAP_LINEAR linear only: size of the map
149 * @ops: map/unmap host callbacks
150 * @inval_irq: provide a hw number in that host space that is always invalid
151 *
152 * Allocates and initialize and irq_host structure. Note that in the case of
153 * IRQ_HOST_MAP_LEGACY, the map() callback will be called before this returns
154 * for all legacy interrupts except 0 (which is always the invalid irq for
155 * a legacy controller). For a IRQ_HOST_MAP_LINEAR, the map is allocated by
156 * this call as well. For a IRQ_HOST_MAP_TREE, the radix tree will be allocated
157 * later during boot automatically (the reverse mapping will use the slow path
158 * until that happens).
159 */
160 extern struct irq_host *irq_alloc_host(struct device_node *of_node,
161 unsigned int revmap_type,
162 unsigned int revmap_arg,
163 struct irq_host_ops *ops,
164 irq_hw_number_t inval_irq);
165
166
167 /**
168 * irq_find_host - Locates a host for a given device node
169 * @node: device-tree node of the interrupt controller
170 */
171 extern struct irq_host *irq_find_host(struct device_node *node);
172
173
174 /**
175 * irq_set_default_host - Set a "default" host
176 * @host: default host pointer
177 *
178 * For convenience, it's possible to set a "default" host that will be used
179 * whenever NULL is passed to irq_create_mapping(). It makes life easier for
180 * platforms that want to manipulate a few hard coded interrupt numbers that
181 * aren't properly represented in the device-tree.
182 */
183 extern void irq_set_default_host(struct irq_host *host);
184
185
186 /**
187 * irq_set_virq_count - Set the maximum number of virt irqs
188 * @count: number of linux virtual irqs, capped with NR_IRQS
189 *
190 * This is mainly for use by platforms like iSeries who want to program
191 * the virtual irq number in the controller to avoid the reverse mapping
192 */
193 extern void irq_set_virq_count(unsigned int count);
194
195
196 /**
197 * irq_create_mapping - Map a hardware interrupt into linux virq space
198 * @host: host owning this hardware interrupt or NULL for default host
199 * @hwirq: hardware irq number in that host space
200 *
201 * Only one mapping per hardware interrupt is permitted. Returns a linux
202 * virq number.
203 * If the sense/trigger is to be specified, set_irq_type() should be called
204 * on the number returned from that call.
205 */
206 extern unsigned int irq_create_mapping(struct irq_host *host,
207 irq_hw_number_t hwirq);
208
209
210 /**
211 * irq_dispose_mapping - Unmap an interrupt
212 * @virq: linux virq number of the interrupt to unmap
213 */
214 extern void irq_dispose_mapping(unsigned int virq);
215
216 /**
217 * irq_find_mapping - Find a linux virq from an hw irq number.
218 * @host: host owning this hardware interrupt
219 * @hwirq: hardware irq number in that host space
220 *
221 * This is a slow path, for use by generic code. It's expected that an
222 * irq controller implementation directly calls the appropriate low level
223 * mapping function.
224 */
225 extern unsigned int irq_find_mapping(struct irq_host *host,
226 irq_hw_number_t hwirq);
227
228 /**
229 * irq_create_direct_mapping - Allocate a virq for direct mapping
230 * @host: host to allocate the virq for or NULL for default host
231 *
232 * This routine is used for irq controllers which can choose the hardware
233 * interrupt numbers they generate. In such a case it's simplest to use
234 * the linux virq as the hardware interrupt number.
235 */
236 extern unsigned int irq_create_direct_mapping(struct irq_host *host);
237
238 /**
239 * irq_radix_revmap_insert - Insert a hw irq to linux virq number mapping.
240 * @host: host owning this hardware interrupt
241 * @virq: linux irq number
242 * @hwirq: hardware irq number in that host space
243 *
244 * This is for use by irq controllers that use a radix tree reverse
245 * mapping for fast lookup.
246 */
247 extern void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,
248 irq_hw_number_t hwirq);
249
250 /**
251 * irq_radix_revmap_lookup - Find a linux virq from a hw irq number.
252 * @host: host owning this hardware interrupt
253 * @hwirq: hardware irq number in that host space
254 *
255 * This is a fast path, for use by irq controller code that uses radix tree
256 * revmaps
257 */
258 extern unsigned int irq_radix_revmap_lookup(struct irq_host *host,
259 irq_hw_number_t hwirq);
260
261 /**
262 * irq_linear_revmap - Find a linux virq from a hw irq number.
263 * @host: host owning this hardware interrupt
264 * @hwirq: hardware irq number in that host space
265 *
266 * This is a fast path, for use by irq controller code that uses linear
267 * revmaps. It does fallback to the slow path if the revmap doesn't exist
268 * yet and will create the revmap entry with appropriate locking
269 */
270
271 extern unsigned int irq_linear_revmap(struct irq_host *host,
272 irq_hw_number_t hwirq);
273
274
275
276 /**
277 * irq_alloc_virt - Allocate virtual irq numbers
278 * @host: host owning these new virtual irqs
279 * @count: number of consecutive numbers to allocate
280 * @hint: pass a hint number, the allocator will try to use a 1:1 mapping
281 *
282 * This is a low level function that is used internally by irq_create_mapping()
283 * and that can be used by some irq controllers implementations for things
284 * like allocating ranges of numbers for MSIs. The revmaps are left untouched.
285 */
286 extern unsigned int irq_alloc_virt(struct irq_host *host,
287 unsigned int count,
288 unsigned int hint);
289
290 /**
291 * irq_free_virt - Free virtual irq numbers
292 * @virq: virtual irq number of the first interrupt to free
293 * @count: number of interrupts to free
294 *
295 * This function is the opposite of irq_alloc_virt. It will not clear reverse
296 * maps, this should be done previously by unmap'ing the interrupt. In fact,
297 * all interrupts covered by the range being freed should have been unmapped
298 * prior to calling this.
299 */
300 extern void irq_free_virt(unsigned int virq, unsigned int count);
301
302
303 /* -- OF helpers -- */
304
305 /* irq_create_of_mapping - Map a hardware interrupt into linux virq space
306 * @controller: Device node of the interrupt controller
307 * @inspec: Interrupt specifier from the device-tree
308 * @intsize: Size of the interrupt specifier from the device-tree
309 *
310 * This function is identical to irq_create_mapping except that it takes
311 * as input informations straight from the device-tree (typically the results
312 * of the of_irq_map_*() functions.
313 */
314 extern unsigned int irq_create_of_mapping(struct device_node *controller,
315 u32 *intspec, unsigned int intsize);
316
317
318 /* irq_of_parse_and_map - Parse nad Map an interrupt into linux virq space
319 * @device: Device node of the device whose interrupt is to be mapped
320 * @index: Index of the interrupt to map
321 *
322 * This function is a wrapper that chains of_irq_map_one() and
323 * irq_create_of_mapping() to make things easier to callers
324 */
325 extern unsigned int irq_of_parse_and_map(struct device_node *dev, int index);
326
327 /* -- End OF helpers -- */
328
329 /**
330 * irq_early_init - Init irq remapping subsystem
331 */
332 extern void irq_early_init(void);
333
irq_canonicalize(int irq)334 static __inline__ int irq_canonicalize(int irq)
335 {
336 return irq;
337 }
338
339 extern int distribute_irqs;
340
341 struct irqaction;
342 struct pt_regs;
343
344 #define __ARCH_HAS_DO_SOFTIRQ
345
346 #if defined(CONFIG_BOOKE) || defined(CONFIG_40x)
347 /*
348 * Per-cpu stacks for handling critical, debug and machine check
349 * level interrupts.
350 */
351 extern struct thread_info *critirq_ctx[NR_CPUS];
352 extern struct thread_info *dbgirq_ctx[NR_CPUS];
353 extern struct thread_info *mcheckirq_ctx[NR_CPUS];
354 extern void exc_lvl_ctx_init(void);
355 #else
356 #define exc_lvl_ctx_init()
357 #endif
358
359 #ifdef CONFIG_IRQSTACKS
360 /*
361 * Per-cpu stacks for handling hard and soft interrupts.
362 */
363 extern struct thread_info *hardirq_ctx[NR_CPUS];
364 extern struct thread_info *softirq_ctx[NR_CPUS];
365
366 extern void irq_ctx_init(void);
367 extern void call_do_softirq(struct thread_info *tp);
368 extern int call_handle_irq(int irq, void *p1,
369 struct thread_info *tp, void *func);
370 #else
371 #define irq_ctx_init()
372
373 #endif /* CONFIG_IRQSTACKS */
374
375 extern void do_IRQ(struct pt_regs *regs);
376
377 #endif /* _ASM_IRQ_H */
378 #endif /* __KERNEL__ */
379