1 /* $NetBSD: isa_irqhandler.c,v 1.29 2020/11/22 03:57:19 thorpej Exp $ */
2
3 /*
4 * Copyright 1997
5 * Digital Equipment Corporation. All rights reserved.
6 *
7 * This software is furnished under license and may be used and
8 * copied only in accordance with the following terms and conditions.
9 * Subject to these conditions, you may download, copy, install,
10 * use, modify and distribute this software in source and/or binary
11 * form. No title or ownership is transferred hereby.
12 *
13 * 1) Any source code used, modified or distributed must reproduce
14 * and retain this copyright notice and list of conditions as
15 * they appear in the source file.
16 *
17 * 2) No right is granted to use any trade name, trademark, or logo of
18 * Digital Equipment Corporation. Neither the "Digital Equipment
19 * Corporation" name nor any trademark or logo of Digital Equipment
20 * Corporation may be used to endorse or promote products derived
21 * from this software without the prior written permission of
22 * Digital Equipment Corporation.
23 *
24 * 3) This software is provided "AS-IS" and any express or implied
25 * warranties, including but not limited to, any implied warranties
26 * of merchantability, fitness for a particular purpose, or
27 * non-infringement are disclaimed. In no event shall DIGITAL be
28 * liable for any damages whatsoever, and in particular, DIGITAL
29 * shall not be liable for special, indirect, consequential, or
30 * incidental damages or damages for lost profits, loss of
31 * revenue or loss of use, whether such damages arise in contract,
32 * negligence, tort, under statute, in equity, at law or otherwise,
33 * even if advised of the possibility of such damage.
34 */
35
36 /*
37 * Copyright (c) 1994-1998 Mark Brinicombe.
38 * Copyright (c) 1994 Brini.
39 * All rights reserved.
40 *
41 * This code is derived from software written for Brini by Mark Brinicombe
42 *
43 * Redistribution and use in source and binary forms, with or without
44 * modification, are permitted provided that the following conditions
45 * are met:
46 * 1. Redistributions of source code must retain the above copyright
47 * notice, this list of conditions and the following disclaimer.
48 * 2. Redistributions in binary form must reproduce the above copyright
49 * notice, this list of conditions and the following disclaimer in the
50 * documentation and/or other materials provided with the distribution.
51 * 3. All advertising materials mentioning features or use of this software
52 * must display the following acknowledgement:
53 * This product includes software developed by Mark Brinicombe
54 * for the NetBSD Project.
55 * 4. The name of the company nor the name of the author may be used to
56 * endorse or promote products derived from this software without specific
57 * prior written permission.
58 *
59 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
60 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
61 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
62 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
63 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
64 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
65 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
66 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
67 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
68 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
69 *
70 * IRQ/FIQ initialisation, claim, release and handler routines
71 *
72 * from: irqhandler.c
73 *
74 * Created : 30/09/94
75 */
76
77 #include <sys/cdefs.h>
78 __KERNEL_RCSID(0, "$NetBSD: isa_irqhandler.c,v 1.29 2020/11/22 03:57:19 thorpej Exp $");
79
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/syslog.h>
83 #include <sys/kmem.h>
84 #include <sys/intr.h>
85
86 #include <arm/locore.h>
87
88 #include <machine/irqhandler.h>
89
90 irqhandler_t *irqhandlers[NIRQS];
91
92 u_int current_mask;
93 u_int actual_mask;
94 u_int disabled_mask;
95 u_int irqmasks[NIPL];
96
97 /* Prototypes */
98
99 extern void set_spl_masks(void);
100 void irq_calculatemasks(void);
101 void stray_irqhandler(u_int);
102
103 #define WriteWord(a, b) *((volatile unsigned int *)(a)) = (b)
104
105 /*
106 * void irq_init(void)
107 *
108 * Initialise the IRQ/FIQ sub system
109 */
110
111 void
irq_init(void)112 irq_init(void)
113 {
114 int loop;
115
116 /* Clear all the IRQ handlers and the irq block masks */
117 for (loop = 0; loop < NIRQS; ++loop) {
118 irqhandlers[loop] = NULL;
119 }
120
121 /*
122 * Setup the irqmasks for the different Interrupt Priority Levels
123 * We will start with no bits set and these will be updated as handlers
124 * are installed at different IPL's.
125 */
126 for (loop = 0; loop < NIPL; ++loop)
127 irqmasks[loop] = 0;
128
129 current_mask = 0x00000000;
130 disabled_mask = 0x00000000;
131 actual_mask = 0x00000000;
132
133 set_spl_masks();
134
135 /* Enable IRQ's and FIQ's */
136 enable_interrupts(I32_bit | F32_bit);
137 }
138
139
140 /*
141 * int irq_claim(int irq, irqhandler_t *handler)
142 *
143 * Enable an IRQ and install a handler for it.
144 */
145
146 int
irq_claim(int irq,irqhandler_t * handler,const char * group,const char * name)147 irq_claim(int irq, irqhandler_t *handler, const char *group, const char *name)
148 {
149
150 #ifdef DIAGNOSTIC
151 /* Sanity check */
152 if (handler == NULL)
153 panic("NULL interrupt handler");
154 if (handler->ih_func == NULL)
155 panic("Interrupt handler does not have a function");
156 #endif /* DIAGNOSTIC */
157
158 /*
159 * IRQ_INSTRUCT indicates that we should get the irq number
160 * from the irq structure
161 */
162 if (irq == IRQ_INSTRUCT)
163 irq = handler->ih_num;
164
165 /* Make sure the irq number is valid */
166 if (irq < 0 || irq >= NIRQS)
167 return(-1);
168
169 /* Make sure the level is valid */
170 if (handler->ih_level < 0 || handler->ih_level >= NIPL)
171 return(-1);
172
173 /* Attach evcnt */
174 evcnt_attach_dynamic(&handler->ih_ev, EVCNT_TYPE_INTR, NULL,
175 group, name);
176
177 /* Attach handler at top of chain */
178 handler->ih_next = irqhandlers[irq];
179 irqhandlers[irq] = handler;
180
181 /*
182 * Reset the flags for this handler.
183 * As the handler is now in the chain mark it as active.
184 */
185 handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
186
187 /*
188 * Record the interrupt number for accounting.
189 * Done here as the accounting number may not be the same as the
190 * IRQ number though for the moment they are
191 */
192 handler->ih_num = irq;
193
194 irq_calculatemasks();
195
196 enable_irq(irq);
197 set_spl_masks();
198 return(0);
199 }
200
201
202 /*
203 * int irq_release(int irq, irqhandler_t *handler)
204 *
205 * Disable an IRQ and remove a handler for it.
206 */
207
208 int
irq_release(int irq,irqhandler_t * handler)209 irq_release(int irq, irqhandler_t *handler)
210 {
211 irqhandler_t *irqhand;
212 irqhandler_t **prehand;
213
214 /*
215 * IRQ_INSTRUCT indicates that we should get the irq number
216 * from the irq structure
217 */
218 if (irq == IRQ_INSTRUCT)
219 irq = handler->ih_num;
220
221 /* Make sure the irq number is valid */
222 if (irq < 0 || irq >= NIRQS)
223 return(-1);
224
225 /* Locate the handler */
226 prehand = &irqhandlers[irq];
227 irqhand = *prehand;
228
229 while (irqhand && handler != irqhand) {
230 prehand = &irqhand->ih_next;
231 irqhand = *prehand;
232 }
233
234 /* Remove the handler if located */
235 if (irqhand)
236 *prehand = irqhand->ih_next;
237 else
238 return(-1);
239
240 /* The handler has been removed from the chain so mark it as inactive */
241 irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
242
243 /* Make sure the head of the handler list is active */
244 if (irqhandlers[irq])
245 irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
246
247 evcnt_detach(&irqhand->ih_ev);
248
249 irq_calculatemasks();
250
251 /*
252 * Disable the appropriate mask bit if there are no handlers left for
253 * this IRQ.
254 */
255 if (irqhandlers[irq] == NULL)
256 disable_irq(irq);
257
258 set_spl_masks();
259
260 return(0);
261 }
262
263 /* adapted from .../i386/isa/isa_machdep.c */
264 /*
265 * Recalculate the interrupt masks from scratch.
266 * We could code special registry and deregistry versions of this function that
267 * would be faster, but the code would be nastier, and we don't expect this to
268 * happen very much anyway.
269 */
270 void
irq_calculatemasks(void)271 irq_calculatemasks(void)
272 {
273 int irq, level;
274 irqhandler_t *ptr;
275 int irqlevel[NIRQS];
276
277 /* First, figure out which levels each IRQ uses. */
278 for (irq = 0; irq < NIRQS; irq++) {
279 int levels = 0;
280 for (ptr = irqhandlers[irq]; ptr; ptr = ptr->ih_next)
281 levels |= 1 << ptr->ih_level;
282 irqlevel[irq] = levels;
283 }
284
285 /* Then figure out which IRQs use each level. */
286 for (level = 0; level < NIPL; level++) {
287 int irqs = 0;
288 for (irq = 0; irq < NIRQS; irq++)
289 if (irqlevel[irq] & (1 << level))
290 irqs |= 1 << irq;
291 irqmasks[level] = ~irqs;
292 }
293
294 /*
295 * Enforce a hierarchy that gives slow devices a better chance at not
296 * dropping data.
297 */
298 KASSERT(irqmasks[IPL_NONE] == ~0);
299 irqmasks[IPL_SOFTCLOCK] &= irqmasks[IPL_NONE];
300 irqmasks[IPL_SOFTBIO] &= irqmasks[IPL_SOFTCLOCK];
301 irqmasks[IPL_SOFTNET] &= irqmasks[IPL_SOFTBIO];
302 irqmasks[IPL_SOFTSERIAL] &= irqmasks[IPL_SOFTNET];
303 irqmasks[IPL_VM] &= irqmasks[IPL_SOFTSERIAL];
304 irqmasks[IPL_CLOCK] &= irqmasks[IPL_VM];
305 irqmasks[IPL_HIGH] &= irqmasks[IPL_CLOCK];
306 }
307
308
309 void *
intr_claim(int irq,int level,int (* ih_func)(void *),void * ih_arg,const char * group,const char * name)310 intr_claim(int irq, int level, int (*ih_func)(void *), void *ih_arg, const char *group, const char *name)
311 {
312 irqhandler_t *ih;
313
314 ih = kmem_zalloc(sizeof(*ih), KM_SLEEP);
315 ih->ih_level = level;
316 ih->ih_func = ih_func;
317 ih->ih_arg = ih_arg;
318 ih->ih_flags = 0;
319
320 if (irq_claim(irq, ih, group, name) != 0) {
321 kmem_free(ih, sizeof(*ih));
322 return(NULL);
323 }
324
325 return(ih);
326 }
327
328 int
intr_release(void * arg)329 intr_release(void *arg)
330 {
331 irqhandler_t *ih = (irqhandler_t *)arg;
332
333 if (irq_release(ih->ih_num, ih) == 0) {
334 kmem_free(ih, sizeof(*ih));
335 return(0);
336 }
337 return(1);
338 }
339
340
341 /*
342 * void disable_irq(int irq)
343 *
344 * Disables a specific irq. The irq is removed from the master irq mask
345 */
346
347 void
disable_irq(int irq)348 disable_irq(int irq)
349 {
350 u_int oldirqstate;
351
352 oldirqstate = disable_interrupts(I32_bit);
353 current_mask &= ~(1 << irq);
354 irq_setmasks();
355 restore_interrupts(oldirqstate);
356 }
357
358
359 /*
360 * void enable_irq(int irq)
361 *
362 * Enables a specific irq. The irq is added to the master irq mask
363 * This routine should be used with caution. A handler should already
364 * be installed.
365 */
366
367 void
enable_irq(int irq)368 enable_irq(int irq)
369 {
370 u_int oldirqstate;
371
372 oldirqstate = disable_interrupts(I32_bit);
373 current_mask |= (1 << irq);
374 irq_setmasks();
375 restore_interrupts(oldirqstate);
376 }
377
378
379 /*
380 * void stray_irqhandler(u_int mask)
381 *
382 * Handler for stray interrupts. This gets called if a handler cannot be
383 * found for an interrupt.
384 */
385
386 void
stray_irqhandler(u_int mask)387 stray_irqhandler(u_int mask)
388 {
389 static u_int stray_irqs = 0;
390
391 if (++stray_irqs <= 8)
392 log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
393 stray_irqs >= 8 ? ": stopped logging" : "");
394 }
395