ofw_irqhandler.c revision 1.13 
1/*	$NetBSD: ofw_irqhandler.c,v 1.13 2008/01/06 03:45:27 matt Exp $	*/
2
3/*
4 * Copyright (c) 1994-1998 Mark Brinicombe.
5 * Copyright (c) 1994 Brini.
6 * All rights reserved.
7 *
8 * This code is derived from software written for Brini by Mark Brinicombe
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by Mark Brinicombe
21 *	for the NetBSD Project.
22 * 4. The name of the company nor the name of the author may be used to
23 *    endorse or promote products derived from this software without specific
24 *    prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 *	from: irqhandler.c
38 *
39 * IRQ/FIQ initialisation, claim, release and handler routines
40 *
41 * Created      : 30/09/94
42 */
43
44#include <sys/cdefs.h>
45__KERNEL_RCSID(0, "$NetBSD: ofw_irqhandler.c,v 1.13 2008/01/06 03:45:27 matt Exp $");
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/syslog.h>
50#include <sys/malloc.h>
51
52#include <uvm/uvm_extern.h>
53
54#include <machine/intr.h>
55#include <machine/irqhandler.h>
56#include <machine/cpu.h>
57
58irqhandler_t *irqhandlers[NIRQS];
59
60u_int current_mask;
61u_int actual_mask;
62u_int disabled_mask;
63u_int irqmasks[IPL_LEVELS];
64extern u_int intrcnt[];
65
66extern char *_intrnames;
67
68/* Prototypes */
69
70int podule_irqhandler		__P((void));
71extern void set_spl_masks	__P((void));
72
73/*
74 * void irq_init(void)
75 *
76 * Initialise the IRQ/FIQ sub system
77 */
78
79void
80irq_init()
81{
82	int loop;
83
84	/* Clear all the IRQ handlers and the irq block masks */
85	for (loop = 0; loop < NIRQS; ++loop) {
86		irqhandlers[loop] = NULL;
87	}
88
89	/*
90	 * Setup the irqmasks for the different Interrupt Priority Levels
91	 * We will start with no bits set and these will be updated as handlers
92	 * are installed at different IPL's.
93	 */
94	for (loop = 0; loop < IPL_LEVELS; ++loop)
95		irqmasks[loop] = 0;
96
97	current_mask = 0x00000000;
98	disabled_mask = 0x00000000;
99	actual_mask = 0x00000000;
100
101	set_spl_masks();
102
103	/* Enable IRQ's and FIQ's */
104	enable_interrupts(I32_bit | F32_bit);
105}
106
107
108/*
109 * int irq_claim(int irq, irqhandler_t *handler)
110 *
111 * Enable an IRQ and install a handler for it.
112 */
113
114int
115irq_claim(irq, handler, group, name)
116	int irq;
117	irqhandler_t *handler;
118	const char *group;
119	const char *name;
120{
121	int level;
122
123#ifdef DIAGNOSTIC
124	/* Sanity check */
125	if (handler == NULL)
126		panic("NULL interrupt handler");
127	if (handler->ih_func == NULL)
128		panic("Interrupt handler does not have a function");
129#endif	/* DIAGNOSTIC */
130
131	/*
132	 * IRQ_INSTRUCT indicates that we should get the irq number
133	 * from the irq structure
134	 */
135	if (irq == IRQ_INSTRUCT)
136		irq = handler->ih_num;
137
138	/* Make sure the irq number is valid */
139	if (irq < 0 || irq >= NIRQS)
140		return(-1);
141
142	/* Make sure the level is valid */
143	if (handler->ih_level < 0 || handler->ih_level >= IPL_LEVELS)
144    	        return(-1);
145
146	evcnt_attach_dynamic(&handler->ih_ev, EVCNT_TYPE_INTR, NULL,
147	    group, name);
148
149	/* Attach handler at top of chain */
150	handler->ih_next = irqhandlers[irq];
151	irqhandlers[irq] = handler;
152
153	/*
154	 * Reset the flags for this handler.
155	 * As the handler is now in the chain mark it as active.
156	 */
157	handler->ih_flags = 0 | IRQ_FLAG_ACTIVE;
158
159	/*
160	 * Record the interrupt number for accounting.
161	 * Done here as the accounting number may not be the same as the
162	 * IRQ number though for the moment they are
163	 */
164	handler->ih_num = irq;
165
166	/*
167	 * Update the irq masks.
168	 * Find the lowest interrupt priority on the irq chain.
169	 * Interrupt is allowable at priorities lower than this.
170	 * If ih_level is out of range then don't bother to update
171	 * the masks.
172	 */
173	if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) {
174		irqhandler_t *ptr;
175
176		/*
177		 * Find the lowest interrupt priority on the irq chain.
178		 * Interrupt is allowable at priorities lower than this.
179		 */
180		ptr = irqhandlers[irq];
181		if (ptr) {
182			level = ptr->ih_level - 1;
183			while (ptr) {
184				if (ptr->ih_level - 1 < level)
185					level = ptr->ih_level - 1;
186				ptr = ptr->ih_next;
187			}
188			while (level >= 0) {
189				irqmasks[level] |= (1 << irq);
190				--level;
191			}
192		}
193
194#include "sl.h"
195#include "ppp.h"
196#if NSL > 0 || NPPP > 0
197		/* In the presence of SLIP or PPP, splimp > spltty. */
198		irqmasks[IPL_NET] &= irqmasks[IPL_TTY];
199#endif
200	}
201
202	enable_irq(irq);
203	set_spl_masks();
204
205	return(0);
206}
207
208
209/*
210 * int irq_release(int irq, irqhandler_t *handler)
211 *
212 * Disable an IRQ and remove a handler for it.
213 */
214
215int
216irq_release(irq, handler)
217	int irq;
218	irqhandler_t *handler;
219{
220	int level;
221	irqhandler_t *irqhand;
222	irqhandler_t **prehand;
223
224	/*
225	 * IRQ_INSTRUCT indicates that we should get the irq number
226	 * from the irq structure
227	 */
228	if (irq == IRQ_INSTRUCT)
229		irq = handler->ih_num;
230
231	/* Make sure the irq number is valid */
232	if (irq < 0 || irq >= NIRQS)
233		return(-1);
234
235	/* Locate the handler */
236	irqhand = irqhandlers[irq];
237	prehand = &irqhandlers[irq];
238
239	while (irqhand && handler != irqhand) {
240		prehand = &irqhand;
241		irqhand = irqhand->ih_next;
242	}
243
244	/* Remove the handler if located */
245	if (irqhand)
246		*prehand = irqhand->ih_next;
247	else
248		return(-1);
249
250	/* Now the handler has been removed from the chain mark is as inactive */
251	irqhand->ih_flags &= ~IRQ_FLAG_ACTIVE;
252
253	/* Make sure the head of the handler list is active */
254	if (irqhandlers[irq])
255		irqhandlers[irq]->ih_flags |= IRQ_FLAG_ACTIVE;
256
257	/*
258	 * Update the irq masks.
259	 * If ih_level is out of range then don't bother to update
260	 * the masks.
261	 */
262	if (handler->ih_level >= 0 && handler->ih_level < IPL_LEVELS) {
263		irqhandler_t *ptr;
264
265		/* Clean the bit from all the masks */
266		for (level = 0; level < IPL_LEVELS; ++level)
267			irqmasks[level] &= ~(1 << irq);
268
269		/*
270		 * Find the lowest interrupt priority on the irq chain.
271		 * Interrupt is allowable at priorities lower than this.
272		 */
273		ptr = irqhandlers[irq];
274		if (ptr) {
275			level = ptr->ih_level - 1;
276			while (ptr) {
277				if (ptr->ih_level - 1 < level)
278					level = ptr->ih_level - 1;
279				ptr = ptr->ih_next;
280			}
281			while (level >= 0) {
282				irqmasks[level] |= (1 << irq);
283				--level;
284			}
285		}
286	}
287
288	/*
289	 * Disable the appropriate mask bit if there are no handlers left for
290	 * this IRQ.
291	 */
292	if (irqhandlers[irq] == NULL)
293		disable_irq(irq);
294
295	set_spl_masks();
296
297	return(0);
298}
299
300
301void *
302intr_claim(irq, level, ih_func, ih_arg, group, name)
303	int irq;
304	int level;
305	int (*ih_func) __P((void *));
306	void *ih_arg;
307	const char *group;
308	const char *name;
309{
310	irqhandler_t *ih;
311
312	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT|M_ZERO);
313	if (!ih)
314		panic("intr_claim(): Cannot malloc handler memory");
315
316	ih->ih_level = level;
317	ih->ih_func = ih_func;
318	ih->ih_arg = ih_arg;
319	ih->ih_flags = 0;
320
321	if (irq_claim(irq, ih, group, name) != 0)
322		return(NULL);
323	return(ih);
324}
325
326
327int
328intr_release(arg)
329	void *arg;
330{
331	irqhandler_t *ih = (irqhandler_t *)arg;
332
333	if (irq_release(ih->ih_num, ih) == 0) {
334		free(ih, M_DEVBUF);
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
347void
348disable_irq(irq)
349	int irq;
350{
351	register int oldirqstate;
352
353	oldirqstate = disable_interrupts(I32_bit);
354	current_mask &= ~(1 << irq);
355	irq_setmasks();
356	restore_interrupts(oldirqstate);
357}
358
359
360/*
361 * void enable_irq(int irq)
362 *
363 * Enables a specific irq. The irq is added to the master irq mask
364 * This routine should be used with caution. A handler should already
365 * be installed.
366 */
367
368void
369enable_irq(irq)
370	int irq;
371{
372	register u_int oldirqstate;
373
374	oldirqstate = disable_interrupts(I32_bit);
375	current_mask |= (1 << irq);
376	irq_setmasks();
377	restore_interrupts(oldirqstate);
378}
379
380
381/*
382 * void stray_irqhandler(u_int mask)
383 *
384 * Handler for stray interrupts. This gets called if a handler cannot be
385 * found for an interrupt.
386 */
387
388void	stray_irqhandler(u_int);	/* called from assembly */
389
390void
391stray_irqhandler(mask)
392	u_int mask;
393{
394	static u_int stray_irqs = 0;
395
396	if (++stray_irqs <= 8)
397		log(LOG_ERR, "Stray interrupt %08x%s\n", mask,
398		    stray_irqs >= 8 ? ": stopped logging" : "");
399}
400