xref: /freebsd/sys/riscv/riscv/aplic.c (revision d584228930a1689479d62fb303a51c42ecd7b6ec)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2024 Himanshu Chauhan <hchauhan@thechauhan.dev>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/bus.h>
31 #include <sys/kernel.h>
32 #include <sys/ktr.h>
33 #include <sys/module.h>
34 #include <sys/proc.h>
35 #include <sys/rman.h>
36 #include <sys/smp.h>
37 
38 #include <machine/bus.h>
39 #include <machine/intr.h>
40 #include <machine/riscvreg.h>
41 
42 #include <dev/ofw/openfirm.h>
43 #include <dev/ofw/ofw_bus.h>
44 #include <dev/ofw/ofw_bus_subr.h>
45 
46 #include "pic_if.h"
47 
48 #define	APLIC_MAX_IRQS		1023
49 
50 /* Smaller priority number means higher priority */
51 #define	APLIC_INTR_DEF_PRIO	1
52 
53 static pic_disable_intr_t	aplic_disable_intr;
54 static pic_enable_intr_t	aplic_enable_intr;
55 static pic_map_intr_t		aplic_map_intr;
56 static pic_setup_intr_t		aplic_setup_intr;
57 static pic_post_ithread_t	aplic_post_ithread;
58 static pic_pre_ithread_t	aplic_pre_ithread;
59 static pic_bind_intr_t		aplic_bind_intr;
60 
61 struct aplic_irqsrc {
62 	struct intr_irqsrc isrc;
63 	u_int irq;
64 };
65 
66 struct aplic_softc {
67 	device_t dev;
68 	struct resource *mem_res;
69 	struct resource *irq_res;
70 	void *ih;
71 	struct aplic_irqsrc isrcs[APLIC_MAX_IRQS + 1];
72 	unsigned int hart_indices[MAXCPU];
73 	int ndev;
74 };
75 
76 #define	APLIC_DOMAIN_CFG_IE		(1UL << 8)	/* Enable domain IRQs */
77 #define	APLIC_DOMAIN_CFG_DM		(1UL << 2)	/* IRQ delivery mode */
78 #define	APLIC_DOMAIN_CFG_BE		(1UL << 0)	/* Endianess */
79 
80 #define	APLIC_MODE_DIRECT		0	/* Direct delivery mode */
81 #define	APLIC_MODE_MSI			1	/* MSI delivery mode */
82 
83 #define	APLIC_SRC_CFG_DLGT		(1UL << 10)	/* Source delegation */
84 #define	APLIC_SRC_CFG_SM_SHIFT		0
85 #define	APLIC_SRC_CFG_SM_MASK		(0x7UL << APLIC_SRC_CFG_SM_SHIFT)
86 
87 #define	APLIC_SRC_CFG_SM_INACTIVE	0	/* APLIC inactive in domain */
88 #define	APLIC_SRC_CFG_SM_DETACHED	1	/* Detached from source wire */
89 #define	APLIC_SRC_CFG_SM_EDGE_RSE	4	/* Asserted on rising edge */
90 #define	APLIC_SRC_CFG_SM_EDGE_FLL	5	/* Asserted on falling edge */
91 #define	APLIC_SRC_CFG_SM_LVL_HI		6	/* Asserted when high */
92 #define	APLIC_SRC_CFG_SM_LVL_LO		7	/* Asserted when low */
93 
94 /* Register offsets in APLIC configuration space */
95 #define	APLIC_DOMAIN_CFG		0x0000
96 #define	APLIC_SRC_CFG(_idx)		(0x0004 + (((_idx) - 1) * 4))
97 #define	APLIC_TARGET(_idx)		(0x3004 + (((_idx) - 1) * 4))
98 #define	APLIC_MMSIADDRCFG		0x1BC0
99 #define	APLIC_MMSIADDRCFGH		0x1BC4
100 #define	APLIC_SMSIADDRCFG		0x1BC8
101 #define	APLIC_SMSIADDRCFGH		0x1BCC
102 #define	APLIC_SETIPNUM			0x1CDC
103 #define	APLIC_CLRIPNUM			0x1DDC
104 #define	APLIC_SETIENUM			0x1EDC
105 #define	APLIC_CLRIENUM			0x1FDC
106 #define	APLIC_SETIPNUM_LE		0x2000
107 #define	APLIC_SETIPNUM_BE		0x2004
108 #define	APLIC_GENMSI			0x3000
109 #define	APLIC_IDC_BASE			0x4000
110 
111 #define	APLIC_SETIE_BASE		0x1E00
112 #define	APLIC_CLRIE_BASE		0x1F00
113 
114 /* Interrupt delivery control structure */
115 #define	APLIC_IDC_IDELIVERY_OFFS	0x0000
116 #define	APLIC_IDC_IFORCE_OFFS		0x0004
117 #define	APLIC_IDC_ITHRESHOLD_OFFS	0x0008
118 #define	APLIC_IDC_TOPI_OFFS		0x0018
119 #define	APLIC_IDC_CLAIMI_OFFS		0x001C
120 
121 #define	APLIC_IDC_SZ			0x20
122 
123 #define	APLIC_IDC_IDELIVERY_DISABLE	0
124 #define	APLIC_IDC_IDELIVERY_ENABLE	1
125 #define	APLIC_IDC_ITHRESHOLD_DISABLE	0
126 
127 #define	APLIC_IDC_CLAIMI_PRIO_MASK	0xff
128 #define	APLIC_IDC_CLAIMI_IRQ_SHIFT	16
129 #define	APLIC_IDC_CLAIMI_IRQ_MASK	0x3ff
130 
131 #define	APLIC_IDC_CLAIMI_IRQ(_claimi)			\
132 	(((_claimi) >> APLIC_IDC_CLAIMI_IRQ_SHIFT)	\
133 	    & APLIC_IDC_CLAIMI_IRQ_MASK)
134 
135 #define	APLIC_IDC_CLAIMI_PRIO(_claimi)	((_claimi) & APLIC_IDC_CLAIMI_PRIO_MASK)
136 
137 #define	APLIC_IDC_REG(_sc, _cpu, _field)		\
138 	(APLIC_IDC_BASE + APLIC_IDC_##_field##_OFFS +	\
139 	    ((_sc->hart_indices[_cpu]) * APLIC_IDC_SZ))
140 
141 #define	APLIC_IDC_IDELIVERY(_sc, _cpu)			\
142 	APLIC_IDC_REG(_sc, _cpu, IDELIVERY)
143 
144 #define	APLIC_IDC_IFORCE(_sc, _cpu)			\
145 	APLIC_IDC_REG(_sc, _cpu, IFORCE)
146 
147 #define	APLIC_IDC_ITHRESHOLD(_sc, _cpu)			\
148 	APLIC_IDC_REG(_sc, _cpu, ITHRESHOLD)
149 
150 #define	APLIC_IDC_TOPI(_sc, _cpu)			\
151 	APLIC_IDC_REG(_sc, _cpu, TOPI)
152 
153 #define	APLIC_IDC_CLAIMI(_sc, _cpu)			\
154 	APLIC_IDC_REG(_sc, _cpu, CLAIMI)
155 
156 #define	APLIC_MK_IRQ_TARGET(_sc, _cpu, _prio)		\
157 	(_sc->hart_indices[_cpu] << 18 | ((_prio) & 0xff))
158 
159 #define	aplic_read(sc, reg)		bus_read_4(sc->mem_res, (reg))
160 #define	aplic_write(sc, reg, val)	bus_write_4(sc->mem_res, (reg), (val))
161 
162 static u_int aplic_irq_cpu;
163 
164 static inline int
riscv_cpu_to_hartid(int cpu)165 riscv_cpu_to_hartid(int cpu)
166 {
167 	return pcpu_find(cpu)->pc_hart;
168 }
169 
170 static inline int
riscv_hartid_to_cpu(int hartid)171 riscv_hartid_to_cpu(int hartid)
172 {
173 	int cpu;
174 
175 	CPU_FOREACH(cpu) {
176 		if (riscv_cpu_to_hartid(cpu) == hartid)
177 			return cpu;
178 	}
179 
180 	return (-1);
181 }
182 
183 static int
fdt_get_hartid(device_t dev,phandle_t aplic)184 fdt_get_hartid(device_t dev, phandle_t aplic)
185 {
186 	int hartid;
187 
188 	/* Check the interrupt controller layout. */
189 	if (OF_searchencprop(aplic, "#interrupt-cells", &hartid,
190 	    sizeof(hartid)) == -1) {
191 		device_printf(dev,
192 		    "Could not find #interrupt-cells for phandle %u\n", aplic);
193 		return (-1);
194 	}
195 
196 	/*
197 	 * The parent of the interrupt-controller is the CPU we are
198 	 * interested in, so search for its hart ID.
199 	 */
200 	if (OF_searchencprop(OF_parent(aplic), "reg", (pcell_t *)&hartid,
201 	    sizeof(hartid)) == -1) {
202 		device_printf(dev, "Could not find hartid\n");
203 		return (-1);
204 	}
205 
206 	return (hartid);
207 }
208 
209 static inline void
aplic_irq_dispatch(struct aplic_softc * sc,u_int irq,u_int prio,struct trapframe * tf)210 aplic_irq_dispatch(struct aplic_softc *sc, u_int irq, u_int prio,
211     struct trapframe *tf)
212 {
213 	struct aplic_irqsrc *src;
214 
215 	src = &sc->isrcs[irq];
216 
217 	if (intr_isrc_dispatch(&src->isrc, tf) != 0)
218 		if (bootverbose)
219 			device_printf(sc->dev, "Stray irq %u detected\n", irq);
220 }
221 
222 static int
aplic_intr(void * arg)223 aplic_intr(void *arg)
224 {
225 	struct aplic_softc *sc;
226 	struct trapframe *tf;
227 	uint32_t claimi;
228 	u_int prio, irq;
229 	int cpu;
230 
231 	sc = arg;
232 	cpu = PCPU_GET(cpuid);
233 
234 	/* Claim all pending interrupts. */
235 	while ((claimi = aplic_read(sc, APLIC_IDC_CLAIMI(sc, cpu))) != 0) {
236 		prio = APLIC_IDC_CLAIMI_PRIO(claimi);
237 		irq = APLIC_IDC_CLAIMI_IRQ(claimi);
238 
239 		KASSERT((irq != 0), ("Invalid IRQ 0"));
240 
241 		tf = curthread->td_intr_frame;
242 		aplic_irq_dispatch(sc, irq, prio, tf);
243 	}
244 
245 	return (FILTER_HANDLED);
246 }
247 
248 static void
aplic_disable_intr(device_t dev,struct intr_irqsrc * isrc)249 aplic_disable_intr(device_t dev, struct intr_irqsrc *isrc)
250 {
251 	struct aplic_softc *sc;
252 	struct aplic_irqsrc *src;
253 
254 	sc = device_get_softc(dev);
255 	src = (struct aplic_irqsrc *)isrc;
256 
257 	/* Disable the interrupt source */
258 	aplic_write(sc, APLIC_CLRIENUM, src->irq);
259 }
260 
261 static void
aplic_enable_intr(device_t dev,struct intr_irqsrc * isrc)262 aplic_enable_intr(device_t dev, struct intr_irqsrc *isrc)
263 {
264 	struct aplic_softc *sc;
265 	struct aplic_irqsrc *src;
266 
267 	sc = device_get_softc(dev);
268 	src = (struct aplic_irqsrc *)isrc;
269 
270 	/* Enable the interrupt source */
271 	aplic_write(sc, APLIC_SETIENUM, src->irq);
272 }
273 
274 static int
aplic_map_intr(device_t dev,struct intr_map_data * data,struct intr_irqsrc ** isrcp)275 aplic_map_intr(device_t dev, struct intr_map_data *data,
276     struct intr_irqsrc **isrcp)
277 {
278 	struct intr_map_data_fdt *daf;
279 	struct aplic_softc *sc;
280 
281 	sc = device_get_softc(dev);
282 
283 	if (data->type != INTR_MAP_DATA_FDT)
284 		return (ENOTSUP);
285 
286 	daf = (struct intr_map_data_fdt *)data;
287 	if (daf->ncells != 2 || daf->cells[0] > sc->ndev) {
288 		device_printf(dev, "Invalid cell data\n");
289 		return (EINVAL);
290 	}
291 
292 	*isrcp = &sc->isrcs[daf->cells[0]].isrc;
293 
294 	return (0);
295 }
296 
297 static int
aplic_probe(device_t dev)298 aplic_probe(device_t dev)
299 {
300 	if (!ofw_bus_status_okay(dev))
301 		return (ENXIO);
302 
303 	if (!ofw_bus_is_compatible(dev, "riscv,aplic"))
304 		return (ENXIO);
305 
306 	device_set_desc(dev, "Advanced Platform-Level Interrupt Controller");
307 
308 	return (BUS_PROBE_DEFAULT);
309 }
310 
311 /*
312  * Setup APLIC in direct mode.
313  */
314 static int
aplic_setup_direct_mode(device_t dev)315 aplic_setup_direct_mode(device_t dev)
316 {
317 	struct aplic_irqsrc *isrcs;
318 	struct aplic_softc *sc;
319 	struct intr_pic *pic;
320 	const char *name;
321 	phandle_t node, xref, iparent;
322 	pcell_t *cells, cell;
323 	int error = ENXIO;
324 	u_int irq;
325 	int cpu, hartid, rid, i, nintr, idc;
326 	device_t rootdev;
327 
328 	sc = device_get_softc(dev);
329 	node = ofw_bus_get_node(dev);
330 
331 	sc->dev = dev;
332 
333 	if ((OF_getencprop(node, "riscv,num-sources", &sc->ndev,
334 	    sizeof(sc->ndev))) < 0) {
335 		device_printf(dev, "Error: could not get number of devices\n");
336 		return (error);
337 	}
338 
339 	if (sc->ndev > APLIC_MAX_IRQS) {
340 		device_printf(dev, "Error: invalid ndev (%d)\n", sc->ndev);
341 		return (error);
342 	}
343 
344 	/* Request memory resources */
345 	rid = 0;
346 	sc->mem_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY, &rid,
347 	    RF_ACTIVE);
348 	if (sc->mem_res == NULL) {
349 		device_printf(dev,
350 		    "Error: could not allocate memory resources\n");
351 		return (error);
352 	}
353 
354 	/* Set APLIC in direct mode and enable all interrupts */
355 	aplic_write(sc, APLIC_DOMAIN_CFG,
356 	    APLIC_MODE_DIRECT | APLIC_DOMAIN_CFG_IE);
357 
358 	/* Register the interrupt sources */
359 	isrcs = sc->isrcs;
360 	name = device_get_nameunit(sc->dev);
361 	for (irq = 1; irq <= sc->ndev; irq++) {
362 		isrcs[irq].irq = irq;
363 
364 		error = intr_isrc_register(&isrcs[irq].isrc, sc->dev,
365 		    0, "%s,%u", name, irq);
366 		if (error != 0)
367 			goto fail;
368 
369 		aplic_write(sc, APLIC_SRC_CFG(irq),
370 		    APLIC_SRC_CFG_SM_DETACHED);
371 	}
372 
373 	nintr = OF_getencprop_alloc_multi(node, "interrupts-extended",
374 	    sizeof(uint32_t), (void **)&cells);
375 	if (nintr <= 0) {
376 		device_printf(dev, "Could not read interrupts-extended\n");
377 		goto fail;
378 	}
379 
380 	/* interrupts-extended is a list of phandles and interrupt types. */
381 	for (i = 0, idc = 0; i < nintr; i += 2, idc++) {
382 		/* Skip M-mode external interrupts */
383 		if (cells[i + 1] != IRQ_EXTERNAL_SUPERVISOR)
384 			continue;
385 
386 		/* Get the hart ID from the CLIC's phandle. */
387 		hartid = fdt_get_hartid(dev, OF_node_from_xref(cells[i]));
388 		if (hartid < 0) {
389 			OF_prop_free(cells);
390 			goto fail;
391 		}
392 
393 		/* Get the corresponding cpuid. */
394 		cpu = riscv_hartid_to_cpu(hartid);
395 		if (cpu < 0) {
396 			device_printf(dev, "Invalid cpu for hart %d\n", hartid);
397 			OF_prop_free(cells);
398 			goto fail;
399 		}
400 
401 		sc->hart_indices[cpu] = idc;
402 	}
403 	OF_prop_free(cells);
404 
405 	/* Turn off the interrupt delivery for all CPUs within or out domain */
406 	CPU_FOREACH(cpu) {
407 		aplic_write(sc, APLIC_IDC_IDELIVERY(sc, cpu),
408 		    APLIC_IDC_IDELIVERY_DISABLE);
409 		aplic_write(sc, APLIC_IDC_ITHRESHOLD(sc, cpu),
410 		    APLIC_IDC_ITHRESHOLD_DISABLE);
411 	}
412 
413 	rootdev = intr_irq_root_device(INTR_ROOT_IRQ);
414 	iparent = OF_xref_from_node(ofw_bus_get_node(rootdev));
415 	cell = IRQ_EXTERNAL_SUPERVISOR;
416 	irq = ofw_bus_map_intr(dev, iparent, 1, &cell);
417 	error = bus_set_resource(dev, SYS_RES_IRQ, 0, irq, 1);
418 	if (error != 0) {
419 		device_printf(dev, "Unable to register IRQ resource\n");
420 		return (ENXIO);
421 	}
422 
423 	rid = 0;
424 	sc->irq_res = bus_alloc_resource_any(dev, SYS_RES_IRQ, &rid,
425 	    RF_ACTIVE);
426 	if (sc->irq_res == NULL) {
427 		device_printf(dev,
428 		    "Error: could not allocate IRQ resources\n");
429 		return (ENXIO);
430 	}
431 
432 	xref = OF_xref_from_node(node);
433 	pic = intr_pic_register(sc->dev, xref);
434 	if (pic == NULL) {
435 		error = ENXIO;
436 		goto fail;
437 	}
438 
439 	error = bus_setup_intr(dev, sc->irq_res, INTR_TYPE_CLK,
440 	    aplic_intr, NULL, sc, &sc->ih);
441 	if (error != 0) {
442 		device_printf(dev, "Unable to setup IRQ resource\n");
443 		return (ENXIO);
444 	}
445 
446 fail:
447 	return (error);
448 }
449 
450 static int
aplic_attach(device_t dev)451 aplic_attach(device_t dev)
452 {
453 	int rc;
454 
455 	/* APLIC with IMSIC on hart is not supported */
456 	if (ofw_bus_has_prop(dev, "msi-parent")) {
457 		device_printf(dev, "APLIC with IMSIC is unsupported\n");
458 		return (ENXIO);
459 	}
460 
461 	rc = aplic_setup_direct_mode(dev);
462 
463 	return (rc);
464 }
465 
466 static void
aplic_pre_ithread(device_t dev,struct intr_irqsrc * isrc)467 aplic_pre_ithread(device_t dev, struct intr_irqsrc *isrc)
468 {
469 	aplic_disable_intr(dev, isrc);
470 }
471 
472 static void
aplic_post_ithread(device_t dev,struct intr_irqsrc * isrc)473 aplic_post_ithread(device_t dev, struct intr_irqsrc *isrc)
474 {
475 	aplic_enable_intr(dev, isrc);
476 }
477 
478 static int
aplic_setup_intr(device_t dev,struct intr_irqsrc * isrc,struct resource * res,struct intr_map_data * data)479 aplic_setup_intr(device_t dev, struct intr_irqsrc *isrc, struct resource *res,
480     struct intr_map_data *data)
481 {
482 	struct aplic_irqsrc *src;
483 	struct aplic_softc *sc;
484 
485 	CPU_ZERO(&isrc->isrc_cpu);
486 
487 	sc = device_get_softc(dev);
488 	src = (struct aplic_irqsrc *)isrc;
489 
490 	aplic_write(sc, APLIC_SRC_CFG(src->irq), APLIC_SRC_CFG_SM_EDGE_RSE);
491 
492 	/*
493 	 * In uniprocessor system, bind_intr will not be called.
494 	 * So bind the interrupt on this CPU. If secondary CPUs
495 	 * are present, then bind_intr will be called again and
496 	 * interrupts will rebind to those CPUs.
497 	 */
498 	aplic_bind_intr(dev, isrc);
499 
500 	return (0);
501 }
502 
503 static int
aplic_bind_intr(device_t dev,struct intr_irqsrc * isrc)504 aplic_bind_intr(device_t dev, struct intr_irqsrc *isrc)
505 {
506 	struct aplic_softc *sc;
507 	struct aplic_irqsrc *src;
508 	uint32_t cpu, hartid;
509 
510 	sc = device_get_softc(dev);
511 	src = (struct aplic_irqsrc *)isrc;
512 
513 	/* Disable the interrupt source */
514 	aplic_write(sc, APLIC_CLRIENUM, src->irq);
515 
516 	if (CPU_EMPTY(&isrc->isrc_cpu)) {
517 		cpu = aplic_irq_cpu = intr_irq_next_cpu(aplic_irq_cpu,
518 		    &all_cpus);
519 		CPU_SETOF(cpu, &isrc->isrc_cpu);
520 	} else {
521 		cpu = CPU_FFS(&isrc->isrc_cpu) - 1;
522 	}
523 
524 	hartid = riscv_cpu_to_hartid(cpu);
525 
526 	if (bootverbose)
527 		device_printf(dev, "Bind irq %d to cpu%d (hart %d)\n", src->irq,
528 		    cpu, hartid);
529 
530 	aplic_write(sc, APLIC_TARGET(src->irq),
531 	    APLIC_MK_IRQ_TARGET(sc, cpu, APLIC_INTR_DEF_PRIO));
532 	aplic_write(sc, APLIC_IDC_IDELIVERY(sc, cpu),
533 	    APLIC_IDC_IDELIVERY_ENABLE);
534 	aplic_enable_intr(dev, isrc);
535 
536 	return (0);
537 }
538 
539 static device_method_t aplic_methods[] = {
540 	DEVMETHOD(device_probe,		aplic_probe),
541 	DEVMETHOD(device_attach,	aplic_attach),
542 
543 	DEVMETHOD(pic_disable_intr,	aplic_disable_intr),
544 	DEVMETHOD(pic_enable_intr,	aplic_enable_intr),
545 	DEVMETHOD(pic_map_intr,		aplic_map_intr),
546 	DEVMETHOD(pic_pre_ithread,	aplic_pre_ithread),
547 	DEVMETHOD(pic_post_ithread,	aplic_post_ithread),
548 	DEVMETHOD(pic_post_filter,	aplic_post_ithread),
549 	DEVMETHOD(pic_setup_intr,	aplic_setup_intr),
550 	DEVMETHOD(pic_bind_intr,	aplic_bind_intr),
551 
552 	DEVMETHOD_END
553 };
554 
555 DEFINE_CLASS_0(aplic, aplic_driver, aplic_methods, sizeof(struct aplic_softc));
556 
557 EARLY_DRIVER_MODULE(aplic, simplebus, aplic_driver, 0, 0,
558     BUS_PASS_INTERRUPT + BUS_PASS_ORDER_MIDDLE);
559