xref: /netbsd-src/sys/arch/arm/ep93xx/ep93xx_intr.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /* $NetBSD: ep93xx_intr.c,v 1.22 2014/03/26 08:51:59 christos 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 1.22 2014/03/26 08:51:59 christos 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 <sys/bus.h>
48 #include <sys/intr.h>
49 
50 #include <arm/locore.h>
51 
52 #include <arm/ep93xx/ep93xxreg.h>
53 #include <arm/ep93xx/ep93xxvar.h>
54 
55 /* Interrupt handler queues. */
56 struct intrq intrq[NIRQ];
57 
58 /* Interrupts to mask at each level. */
59 static uint32_t vic1_imask[NIPL];
60 static uint32_t vic2_imask[NIPL];
61 
62 /* Current interrupt priority level. */
63 volatile int hardware_spl_level;
64 
65 /* Software copy of the IRQs we have enabled. */
66 volatile uint32_t vic1_intr_enabled;
67 volatile uint32_t vic2_intr_enabled;
68 
69 void	ep93xx_intr_dispatch(struct trapframe *);
70 
71 #define VIC1REG(reg)	*((volatile uint32_t*) (EP93XX_AHB_VBASE + \
72 	EP93XX_AHB_VIC1 + (reg)))
73 #define VIC2REG(reg)	*((volatile uint32_t*) (EP93XX_AHB_VBASE + \
74 	EP93XX_AHB_VIC2 + (reg)))
75 
76 static void
77 ep93xx_set_intrmask(uint32_t vic1_irqs, uint32_t vic2_irqs)
78 {
79 	VIC1REG(EP93XX_VIC_IntEnClear) = vic1_irqs;
80 	VIC1REG(EP93XX_VIC_IntEnable) = vic1_intr_enabled & ~vic1_irqs;
81 	VIC2REG(EP93XX_VIC_IntEnClear) = vic2_irqs;
82 	VIC2REG(EP93XX_VIC_IntEnable) = vic2_intr_enabled & ~vic2_irqs;
83 }
84 
85 static void
86 ep93xx_enable_irq(int irq)
87 {
88 	if (irq < VIC_NIRQ) {
89 		vic1_intr_enabled |= (1U << irq);
90 		VIC1REG(EP93XX_VIC_IntEnable) = (1U << irq);
91 	} else {
92 		vic2_intr_enabled |= (1U << (irq - VIC_NIRQ));
93 		VIC2REG(EP93XX_VIC_IntEnable) = (1U << (irq - VIC_NIRQ));
94 	}
95 }
96 
97 static inline void
98 ep93xx_disable_irq(int irq)
99 {
100 	if (irq < VIC_NIRQ) {
101 		vic1_intr_enabled &= ~(1U << irq);
102 		VIC1REG(EP93XX_VIC_IntEnClear) = (1U << irq);
103 	} else {
104 		vic2_intr_enabled &= ~(1U << (irq - VIC_NIRQ));
105 		VIC2REG(EP93XX_VIC_IntEnClear) = (1U << (irq - VIC_NIRQ));
106 	}
107 }
108 
109 /*
110  * NOTE: This routine must be called with interrupts disabled in the CPSR.
111  */
112 static void
113 ep93xx_intr_calculate_masks(void)
114 {
115 	struct intrq *iq;
116 	struct intrhand *ih;
117 	int irq, ipl;
118 
119 	/* First, figure out which IPLs each IRQ has. */
120 	for (irq = 0; irq < NIRQ; irq++) {
121 		int levels = 0;
122 		iq = &intrq[irq];
123 		ep93xx_disable_irq(irq);
124 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
125 		     ih = TAILQ_NEXT(ih, ih_list))
126 			levels |= (1U << ih->ih_ipl);
127 		iq->iq_levels = levels;
128 	}
129 
130 	/* Next, figure out which IRQs are used by each IPL. */
131 	for (ipl = 0; ipl < NIPL; ipl++) {
132 		int vic1_irqs = 0;
133 		int vic2_irqs = 0;
134 		for (irq = 0; irq < VIC_NIRQ; irq++) {
135 			if (intrq[irq].iq_levels & (1U << ipl))
136 				vic1_irqs |= (1U << irq);
137 		}
138 		vic1_imask[ipl] = vic1_irqs;
139 		for (irq = 0; irq < VIC_NIRQ; irq++) {
140 			if (intrq[irq + VIC_NIRQ].iq_levels & (1U << ipl))
141 				vic2_irqs |= (1U << irq);
142 		}
143 		vic2_imask[ipl] = vic2_irqs;
144 	}
145 
146 	KASSERT(vic1_imask[IPL_NONE] == 0);
147 	KASSERT(vic2_imask[IPL_NONE] == 0);
148 	KASSERT(vic1_imask[IPL_SOFTCLOCK] == 0);
149 	KASSERT(vic2_imask[IPL_SOFTCLOCK] == 0);
150 	KASSERT(vic1_imask[IPL_SOFTBIO] == 0);
151 	KASSERT(vic2_imask[IPL_SOFTBIO] == 0);
152 	KASSERT(vic1_imask[IPL_SOFTNET] == 0);
153 	KASSERT(vic2_imask[IPL_SOFTNET] == 0);
154 	KASSERT(vic1_imask[IPL_SOFTSERIAL] == 0);
155 	KASSERT(vic2_imask[IPL_SOFTSERIAL] == 0);
156 
157 	/*
158 	 * splsched() must block anything that uses the scheduler.
159 	 */
160 	vic1_imask[IPL_SCHED] |= vic1_imask[IPL_VM];
161 	vic2_imask[IPL_SCHED] |= vic2_imask[IPL_VM];
162 
163 	/*
164 	 * splhigh() must block "everything".
165 	 */
166 	vic1_imask[IPL_HIGH] |= vic1_imask[IPL_SCHED];
167 	vic2_imask[IPL_HIGH] |= vic2_imask[IPL_SCHED];
168 
169 	/*
170 	 * Now compute which IRQs must be blocked when servicing any
171 	 * given IRQ.
172 	 */
173 	for (irq = 0; irq < NIRQ; irq++) {
174 		int	vic1_irqs;
175 		int	vic2_irqs;
176 
177 		if (irq < VIC_NIRQ) {
178 			vic1_irqs = (1U << irq);
179 			vic2_irqs = 0;
180 		} else {
181 			vic1_irqs = 0;
182 			vic2_irqs = (1U << (irq - VIC_NIRQ));
183 		}
184 		iq = &intrq[irq];
185 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
186 			ep93xx_enable_irq(irq);
187 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
188 		     ih = TAILQ_NEXT(ih, ih_list)) {
189 			vic1_irqs |= vic1_imask[ih->ih_ipl];
190 			vic2_irqs |= vic2_imask[ih->ih_ipl];
191 		}
192 		iq->iq_vic1_mask = vic1_irqs;
193 		iq->iq_vic2_mask = vic2_irqs;
194 	}
195 }
196 
197 inline void
198 splx(int new)
199 {
200 	u_int	oldirqstate;
201 
202 	oldirqstate = disable_interrupts(I32_bit);
203 	set_curcpl(new);
204 	if (new != hardware_spl_level) {
205 		hardware_spl_level = new;
206 		ep93xx_set_intrmask(vic1_imask[new], vic2_imask[new]);
207 	}
208 	restore_interrupts(oldirqstate);
209 
210 #ifdef __HAVE_FAST_SOFTINTS
211 	cpu_dosoftints();
212 #endif
213 }
214 
215 int
216 _splraise(int ipl)
217 {
218 	int	old;
219 	u_int	oldirqstate;
220 
221 	oldirqstate = disable_interrupts(I32_bit);
222 	old = curcpl();
223 	set_curcpl(ipl);
224 	restore_interrupts(oldirqstate);
225 	return (old);
226 }
227 
228 int
229 _spllower(int ipl)
230 {
231 	int	old = curcpl();
232 
233 	if (old <= ipl)
234 		return (old);
235 	splx(ipl);
236 	return (old);
237 }
238 
239 /*
240  * ep93xx_intr_init:
241  *
242  *	Initialize the rest of the interrupt subsystem, making it
243  *	ready to handle interrupts from devices.
244  */
245 void
246 ep93xx_intr_init(void)
247 {
248 	struct intrq *iq;
249 	int i;
250 
251 	vic1_intr_enabled = 0;
252 	vic2_intr_enabled = 0;
253 
254 	for (i = 0; i < NIRQ; i++) {
255 		iq = &intrq[i];
256 		TAILQ_INIT(&iq->iq_list);
257 
258 		snprintf(iq->iq_name, sizeof(iq->iq_name), "irq %d", i);
259 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
260 				     NULL, (i < VIC_NIRQ ? "vic1" : "vic2"),
261 		                     iq->iq_name);
262 	}
263 	curcpu()->ci_intr_depth = 0;
264 	set_curcpl(0);
265 	hardware_spl_level = 0;
266 
267 	/* All interrupts should use IRQ not FIQ */
268 	VIC1REG(EP93XX_VIC_IntSelect) = 0;
269 	VIC2REG(EP93XX_VIC_IntSelect) = 0;
270 
271 	ep93xx_intr_calculate_masks();
272 
273 	/* Enable IRQs (don't yet use FIQs). */
274 	enable_interrupts(I32_bit);
275 }
276 
277 void *
278 ep93xx_intr_establish(int irq, int ipl, int (*ih_func)(void *), void *arg)
279 {
280 	struct intrq*		iq;
281 	struct intrhand*	ih;
282 	u_int			oldirqstate;
283 
284 	if (irq < 0 || irq > NIRQ)
285 		panic("ep93xx_intr_establish: IRQ %d out of range", irq);
286 	if (ipl < 0 || ipl > NIPL)
287 		panic("ep93xx_intr_establish: IPL %d out of range", ipl);
288 
289 	ih = malloc(sizeof(*ih), M_DEVBUF, M_NOWAIT);
290 	if (ih == NULL)
291 		return (NULL);
292 
293 	ih->ih_func = ih_func;
294 	ih->ih_arg = arg;
295 	ih->ih_irq = irq;
296 	ih->ih_ipl = ipl;
297 
298 	iq = &intrq[irq];
299 
300 	oldirqstate = disable_interrupts(I32_bit);
301 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
302 	ep93xx_intr_calculate_masks();
303 	restore_interrupts(oldirqstate);
304 
305 	return (ih);
306 }
307 
308 void
309 ep93xx_intr_disestablish(void *cookie)
310 {
311 	struct intrhand*	ih = cookie;
312 	struct intrq*		iq = &intrq[ih->ih_irq];
313 	u_int			oldirqstate;
314 
315 	oldirqstate = disable_interrupts(I32_bit);
316 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
317 	ep93xx_intr_calculate_masks();
318 	restore_interrupts(oldirqstate);
319 }
320 
321 void
322 ep93xx_intr_dispatch(struct trapframe *frame)
323 {
324 	struct intrq*		iq;
325 	struct intrhand*	ih;
326 	u_int			oldirqstate;
327 	int			pcpl;
328 	uint32_t		vic1_hwpend;
329 	uint32_t		vic2_hwpend;
330 	int			irq;
331 
332 	pcpl = curcpl();
333 
334 	vic1_hwpend = VIC1REG(EP93XX_VIC_IRQStatus);
335 	vic2_hwpend = VIC2REG(EP93XX_VIC_IRQStatus);
336 
337 	hardware_spl_level = pcpl;
338 	ep93xx_set_intrmask(vic1_imask[pcpl] | vic1_hwpend,
339 			     vic2_imask[pcpl] | vic2_hwpend);
340 
341 	vic1_hwpend &= ~vic1_imask[pcpl];
342 	vic2_hwpend &= ~vic2_imask[pcpl];
343 
344 	if (vic1_hwpend) {
345 		irq = ffs(vic1_hwpend) - 1;
346 
347 		iq = &intrq[irq];
348 		iq->iq_ev.ev_count++;
349 		curcpu()->ci_data.cpu_nintr++;
350 		TAILQ_FOREACH(ih, &iq->iq_list, ih_list) {
351 			set_curcpl(ih->ih_ipl);
352 			oldirqstate = enable_interrupts(I32_bit);
353 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
354 			restore_interrupts(oldirqstate);
355 		}
356 	} else if (vic2_hwpend) {
357 		irq = ffs(vic2_hwpend) - 1;
358 
359 		iq = &intrq[irq + VIC_NIRQ];
360 		iq->iq_ev.ev_count++;
361 		curcpu()->ci_data.cpu_nintr++;
362 		TAILQ_FOREACH(ih, &iq->iq_list, ih_list) {
363 			set_curcpl(ih->ih_ipl);
364 			oldirqstate = enable_interrupts(I32_bit);
365 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
366 			restore_interrupts(oldirqstate);
367 		}
368 	}
369 
370 	set_curcpl(pcpl);
371 	hardware_spl_level = pcpl;
372 	ep93xx_set_intrmask(vic1_imask[pcpl], vic2_imask[pcpl]);
373 
374 #ifdef __HAVE_FAST_SOFTINTS
375 	cpu_dosoftints();
376 #endif
377 }
378