xref: /netbsd-src/sys/arch/arm/ep93xx/ep93xx_intr.c (revision 404fbe5fb94ca1e054339640cabb2801ce52dd30)
1 /* $NetBSD: ep93xx_intr.c,v 1.13 2008/04/28 20:23:14 martin Exp $ */
2 
3 /*
4  * Copyright (c) 2002 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Jesse Off
9  *
10  * This code is derived from software contributed to The NetBSD Foundation
11  * by Ichiro FUKUHARA and Naoto Shimazaki.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
25  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
26  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
29  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
30  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
31  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
32  * POSSIBILITY OF SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: ep93xx_intr.c,v 1.13 2008/04/28 20:23:14 martin Exp $");
37 
38 /*
39  * Interrupt support for the Cirrus Logic EP93XX
40  */
41 
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/malloc.h>
45 #include <sys/termios.h>
46 
47 #include <uvm/uvm_extern.h>
48 
49 #include <machine/bus.h>
50 #include <machine/intr.h>
51 
52 #include <arm/cpufunc.h>
53 
54 #include <arm/ep93xx/ep93xxreg.h>
55 #include <arm/ep93xx/ep93xxvar.h>
56 
57 /* Interrupt handler queues. */
58 struct intrq intrq[NIRQ];
59 
60 /* Interrupts to mask at each level. */
61 static u_int32_t vic1_imask[NIPL];
62 static u_int32_t vic2_imask[NIPL];
63 
64 /* Current interrupt priority level. */
65 volatile int hardware_spl_level;
66 
67 /* Software copy of the IRQs we have enabled. */
68 volatile u_int32_t vic1_intr_enabled;
69 volatile u_int32_t vic2_intr_enabled;
70 
71 /* Interrupts pending. */
72 static volatile int ipending;
73 
74 void	ep93xx_intr_dispatch(struct irqframe *frame);
75 
76 #define VIC1REG(reg)	*((volatile u_int32_t*) (EP93XX_AHB_VBASE + \
77 	EP93XX_AHB_VIC1 + (reg)))
78 #define VIC2REG(reg)	*((volatile u_int32_t*) (EP93XX_AHB_VBASE + \
79 	EP93XX_AHB_VIC2 + (reg)))
80 
81 static void
82 ep93xx_set_intrmask(u_int32_t vic1_irqs, u_int32_t vic2_irqs)
83 {
84 	VIC1REG(EP93XX_VIC_IntEnClear) = vic1_irqs;
85 	VIC1REG(EP93XX_VIC_IntEnable) = vic1_intr_enabled & ~vic1_irqs;
86 	VIC2REG(EP93XX_VIC_IntEnClear) = vic2_irqs;
87 	VIC2REG(EP93XX_VIC_IntEnable) = vic2_intr_enabled & ~vic2_irqs;
88 }
89 
90 static void
91 ep93xx_enable_irq(int irq)
92 {
93 	if (irq < VIC_NIRQ) {
94 		vic1_intr_enabled |= (1U << irq);
95 		VIC1REG(EP93XX_VIC_IntEnable) = (1U << irq);
96 	} else {
97 		vic2_intr_enabled |= (1U << (irq - VIC_NIRQ));
98 		VIC2REG(EP93XX_VIC_IntEnable) = (1U << (irq - VIC_NIRQ));
99 	}
100 }
101 
102 static inline void
103 ep93xx_disable_irq(int irq)
104 {
105 	if (irq < VIC_NIRQ) {
106 		vic1_intr_enabled &= ~(1U << irq);
107 		VIC1REG(EP93XX_VIC_IntEnClear) = (1U << irq);
108 	} else {
109 		vic2_intr_enabled &= ~(1U << (irq - VIC_NIRQ));
110 		VIC2REG(EP93XX_VIC_IntEnClear) = (1U << (irq - VIC_NIRQ));
111 	}
112 }
113 
114 /*
115  * NOTE: This routine must be called with interrupts disabled in the CPSR.
116  */
117 static void
118 ep93xx_intr_calculate_masks(void)
119 {
120 	struct intrq *iq;
121 	struct intrhand *ih;
122 	int irq, ipl;
123 
124 	/* First, figure out which IPLs each IRQ has. */
125 	for (irq = 0; irq < NIRQ; irq++) {
126 		int levels = 0;
127 		iq = &intrq[irq];
128 		ep93xx_disable_irq(irq);
129 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
130 		     ih = TAILQ_NEXT(ih, ih_list))
131 			levels |= (1U << ih->ih_ipl);
132 		iq->iq_levels = levels;
133 	}
134 
135 	/* Next, figure out which IRQs are used by each IPL. */
136 	for (ipl = 0; ipl < NIPL; ipl++) {
137 		int vic1_irqs = 0;
138 		int vic2_irqs = 0;
139 		for (irq = 0; irq < VIC_NIRQ; irq++) {
140 			if (intrq[irq].iq_levels & (1U << ipl))
141 				vic1_irqs |= (1U << irq);
142 		}
143 		vic1_imask[ipl] = vic1_irqs;
144 		for (irq = 0; irq < VIC_NIRQ; irq++) {
145 			if (intrq[irq + VIC_NIRQ].iq_levels & (1U << ipl))
146 				vic2_irqs |= (1U << irq);
147 		}
148 		vic2_imask[ipl] = vic2_irqs;
149 	}
150 
151 	KASSERT(vic1_imask[IPL_NONE] == 0);
152 	KASSERT(vic2_imask[IPL_NONE] == 0);
153 
154 	/*
155 	 * splclock() must block anything that uses the scheduler.
156 	 */
157 	vic1_imask[IPL_SCHED] |= vic1_imask[IPL_VM];
158 	vic2_imask[IPL_SCHED] |= vic2_imask[IPL_VM];
159 
160 	/*
161 	 * splhigh() must block "everything".
162 	 */
163 	vic1_imask[IPL_HIGH] |= vic1_imask[IPL_SCHED];
164 	vic2_imask[IPL_HIGH] |= vic2_imask[IPL_SCHED];
165 
166 	/*
167 	 * Now compute which IRQs must be blocked when servicing any
168 	 * given IRQ.
169 	 */
170 	for (irq = 0; irq < NIRQ; irq++) {
171 		int	vic1_irqs;
172 		int	vic2_irqs;
173 
174 		if (irq < VIC_NIRQ) {
175 			vic1_irqs = (1U << irq);
176 			vic2_irqs = 0;
177 		} else {
178 			vic1_irqs = 0;
179 			vic2_irqs = (1U << (irq - VIC_NIRQ));
180 		}
181 		iq = &intrq[irq];
182 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
183 			ep93xx_enable_irq(irq);
184 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
185 		     ih = TAILQ_NEXT(ih, ih_list)) {
186 			vic1_irqs |= vic1_imask[ih->ih_ipl];
187 			vic2_irqs |= vic2_imask[ih->ih_ipl];
188 		}
189 		iq->iq_vic1_mask = vic1_irqs;
190 		iq->iq_vic2_mask = vic2_irqs;
191 	}
192 }
193 
194 inline void
195 splx(int new)
196 {
197 	int	old;
198 	u_int	oldirqstate;
199 
200 	oldirqstate = disable_interrupts(I32_bit);
201 	old = curcpl();
202 	set_curcpl(new);
203 	if (new != hardware_spl_level) {
204 		hardware_spl_level = new;
205 		ep93xx_set_intrmask(vic1_imask[new], vic2_imask[new]);
206 	}
207 	restore_interrupts(oldirqstate);
208 
209 #ifdef __HAVE_FAST_SOFTINTS
210 	cpu_dosoftints();
211 #endif
212 }
213 
214 int
215 _splraise(int ipl)
216 {
217 	int	old;
218 	u_int	oldirqstate;
219 
220 	oldirqstate = disable_interrupts(I32_bit);
221 	old = curcpl();
222 	set_curcpl(ipl);
223 	restore_interrupts(oldirqstate);
224 	return (old);
225 }
226 
227 int
228 _spllower(int ipl)
229 {
230 	int	old = curcpl();
231 
232 	if (old <= ipl)
233 		return (old);
234 	splx(ipl);
235 	return (old);
236 }
237 
238 /*
239  * ep93xx_intr_init:
240  *
241  *	Initialize the rest of the interrupt subsystem, making it
242  *	ready to handle interrupts from devices.
243  */
244 void
245 ep93xx_intr_init(void)
246 {
247 	struct intrq *iq;
248 	int i;
249 
250 	vic1_intr_enabled = 0;
251 	vic2_intr_enabled = 0;
252 
253 	for (i = 0; i < NIRQ; i++) {
254 		iq = &intrq[i];
255 		TAILQ_INIT(&iq->iq_list);
256 
257 		sprintf(iq->iq_name, "irq %d", i);
258 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
259 				     NULL, (i < VIC_NIRQ ? "vic1" : "vic2"),
260 		                     iq->iq_name);
261 	}
262 	curcpu()->ci_intr_depth = 0;
263 	set_curcpl(0);
264 	hardware_spl_level = 0;
265 
266 	/* All interrupts should use IRQ not FIQ */
267 	VIC1REG(EP93XX_VIC_IntSelect) = 0;
268 	VIC2REG(EP93XX_VIC_IntSelect) = 0;
269 
270 	ep93xx_intr_calculate_masks();
271 
272 	/* Enable IRQs (don't yet use FIQs). */
273 	enable_interrupts(I32_bit);
274 }
275 
276 void *
277 ep93xx_intr_establish(int irq, int ipl, int (*ih_func)(void *), void *arg)
278 {
279 	struct intrq*		iq;
280 	struct intrhand*	ih;
281 	u_int			oldirqstate;
282 
283 	if (irq < 0 || irq > NIRQ)
284 		panic("ep93xx_intr_establish: IRQ %d out of range", irq);
285 	if (ipl < 0 || ipl > NIPL)
286 		panic("ep93xx_intr_establish: IPL %d out of range", ipl);
287 
288 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
289 	if (ih == NULL)
290 		return (NULL);
291 
292 	ih->ih_func = ih_func;
293 	ih->ih_arg = arg;
294 	ih->ih_irq = irq;
295 	ih->ih_ipl = ipl;
296 
297 	iq = &intrq[irq];
298 
299 	oldirqstate = disable_interrupts(I32_bit);
300 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
301 	ep93xx_intr_calculate_masks();
302 	restore_interrupts(oldirqstate);
303 
304 	return (ih);
305 }
306 
307 void
308 ep93xx_intr_disestablish(void *cookie)
309 {
310 	struct intrhand*	ih = cookie;
311 	struct intrq*		iq = &intrq[ih->ih_irq];
312 	u_int			oldirqstate;
313 
314 	oldirqstate = disable_interrupts(I32_bit);
315 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
316 	ep93xx_intr_calculate_masks();
317 	restore_interrupts(oldirqstate);
318 }
319 
320 void
321 ep93xx_intr_dispatch(struct irqframe *frame)
322 {
323 	struct intrq*		iq;
324 	struct intrhand*	ih;
325 	u_int			oldirqstate;
326 	int			pcpl;
327 	u_int32_t		vic1_hwpend;
328 	u_int32_t		vic2_hwpend;
329 	int			irq;
330 
331 	pcpl = curcpl();
332 
333 	vic1_hwpend = VIC1REG(EP93XX_VIC_IRQStatus);
334 	vic2_hwpend = VIC2REG(EP93XX_VIC_IRQStatus);
335 
336 	hardware_spl_level = pcpl;
337 	ep93xx_set_intrmask(vic1_imask[pcpl] | vic1_hwpend,
338 			     vic2_imask[pcpl] | vic2_hwpend);
339 
340 	vic1_hwpend &= ~vic1_imask[pcpl];
341 	vic2_hwpend &= ~vic2_imask[pcpl];
342 
343 	if (vic1_hwpend) {
344 		irq = ffs(vic1_hwpend) - 1;
345 
346 		iq = &intrq[irq];
347 		iq->iq_ev.ev_count++;
348 		uvmexp.intrs++;
349 		TAILQ_FOREACH(ih, &iq->iq_list, ih_list) {
350 			set_curcpl(ih->ih_ipl);
351 			oldirqstate = enable_interrupts(I32_bit);
352 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
353 			restore_interrupts(oldirqstate);
354 		}
355 	} else if (vic2_hwpend) {
356 		irq = ffs(vic2_hwpend) - 1;
357 
358 		iq = &intrq[irq + VIC_NIRQ];
359 		iq->iq_ev.ev_count++;
360 		uvmexp.intrs++;
361 		TAILQ_FOREACH(ih, &iq->iq_list, ih_list) {
362 			set_curcpl(ih->ih_ipl);
363 			oldirqstate = enable_interrupts(I32_bit);
364 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
365 			restore_interrupts(oldirqstate);
366 		}
367 	}
368 
369 	set_curcpl(pcpl);
370 	hardware_spl_level = pcpl;
371 	ep93xx_set_intrmask(vic1_imask[pcpl], vic2_imask[pcpl]);
372 
373 #ifdef __HAVE_FAST_SOFTINTS
374 	cpu_dosoftints();
375 #endif
376 }
377