1/*-
2 * Copyright (c) 2009 Neelkanth Natu
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD$");
29
30#include <sys/param.h>
31#include <sys/kernel.h>
32#include <sys/systm.h>
33#include <sys/module.h>
34#include <sys/bus.h>
35#include <sys/malloc.h>
36#include <sys/rman.h>
37#include <sys/lock.h>
38#include <sys/mutex.h>
39
40#include <machine/resource.h>
41#include <machine/intr_machdep.h>
42
43#include "sb_scd.h"
44
45static MALLOC_DEFINE(M_INTMAP, "sb1250 intmap", "Sibyte 1250 Interrupt Mapper");
46
47static struct mtx zbbus_intr_mtx;
48MTX_SYSINIT(zbbus_intr_mtx, &zbbus_intr_mtx, "zbbus_intr_mask/unmask lock",
49	    MTX_SPIN);
50
51/*
52 * This array holds the mapping between a MIPS hard interrupt and the
53 * interrupt sources that feed into that it.
54 */
55static uint64_t hardint_to_intsrc_mask[NHARD_IRQS];
56
57struct sb_intmap {
58	int intsrc;		/* interrupt mapper register number (0 - 63) */
59	int hardint;		/* cpu interrupt from 0 to NHARD_IRQS - 1 */
60
61	/*
62	 * The device that the interrupt belongs to. Note that multiple
63	 * devices may share an interrupt. For e.g. PCI_INT_x lines.
64	 *
65	 * The device 'dev' in combination with the 'rid' uniquely
66	 * identify this interrupt source.
67	 */
68	device_t dev;
69	int rid;
70
71	SLIST_ENTRY(sb_intmap) next;
72};
73
74static SLIST_HEAD(, sb_intmap) sb_intmap_head;
75
76static struct sb_intmap *
77sb_intmap_lookup(int intrnum, device_t dev, int rid)
78{
79	struct sb_intmap *map;
80
81	SLIST_FOREACH(map, &sb_intmap_head, next) {
82		if (dev == map->dev && rid == map->rid &&
83		    intrnum == map->hardint)
84			break;
85	}
86	return (map);
87}
88
89/*
90 * Keep track of which (dev,rid,hardint) tuple is using the interrupt source.
91 *
92 * We don't actually unmask the interrupt source until the device calls
93 * a bus_setup_intr() on the resource.
94 */
95static void
96sb_intmap_add(int intrnum, device_t dev, int rid, int intsrc)
97{
98	struct sb_intmap *map;
99
100	KASSERT(intrnum >= 0 && intrnum < NHARD_IRQS,
101		("intrnum is out of range: %d", intrnum));
102
103	map = sb_intmap_lookup(intrnum, dev, rid);
104	if (map) {
105		KASSERT(intsrc == map->intsrc,
106			("%s%d allocating SYS_RES_IRQ resource with rid %d "
107			 "with a different intsrc (%d versus %d)",
108			device_get_name(dev), device_get_unit(dev), rid,
109			intsrc, map->intsrc));
110		return;
111	}
112
113	map = malloc(sizeof(*map), M_INTMAP, M_WAITOK | M_ZERO);
114	map->intsrc = intsrc;
115	map->hardint = intrnum;
116	map->dev = dev;
117	map->rid = rid;
118
119	SLIST_INSERT_HEAD(&sb_intmap_head, map, next);
120}
121
122static void
123sb_intmap_activate(int intrnum, device_t dev, int rid)
124{
125	struct sb_intmap *map;
126
127	KASSERT(intrnum >= 0 && intrnum < NHARD_IRQS,
128		("intrnum is out of range: %d", intrnum));
129
130	map = sb_intmap_lookup(intrnum, dev, rid);
131	if (map) {
132		/*
133		 * Deliver all interrupts to CPU0.
134		 */
135		mtx_lock_spin(&zbbus_intr_mtx);
136		hardint_to_intsrc_mask[intrnum] |= 1ULL << map->intsrc;
137		sb_enable_intsrc(0, map->intsrc);
138		mtx_unlock_spin(&zbbus_intr_mtx);
139	} else {
140		/*
141		 * In zbbus_setup_intr() we blindly call sb_intmap_activate()
142		 * for every interrupt activation that comes our way.
143		 *
144		 * We might end up here if we did not "hijack" the SYS_RES_IRQ
145		 * resource in zbbus_alloc_resource().
146		 */
147		printf("sb_intmap_activate: unable to activate interrupt %d "
148		       "for device %s%d rid %d.\n", intrnum,
149		       device_get_name(dev), device_get_unit(dev), rid);
150	}
151}
152
153/*
154 * Replace the default interrupt mask and unmask routines in intr_machdep.c
155 * with routines that are SMP-friendly. In contrast to the default mask/unmask
156 * routines in intr_machdep.c these routines do not change the SR.int_mask bits.
157 *
158 * Instead they use the interrupt mapper to either mask or unmask all
159 * interrupt sources feeding into a particular interrupt line of the processor.
160 *
161 * This means that these routines have an identical effect irrespective of
162 * which cpu is executing them. This is important because the ithread may
163 * be scheduled to run on either of the cpus.
164 */
165static void
166zbbus_intr_mask(void *arg)
167{
168	uint64_t mask;
169	int irq;
170
171	irq = (uintptr_t)arg;
172
173	mtx_lock_spin(&zbbus_intr_mtx);
174
175	mask = sb_read_intsrc_mask(0);
176	mask |= hardint_to_intsrc_mask[irq];
177	sb_write_intsrc_mask(0, mask);
178
179	mtx_unlock_spin(&zbbus_intr_mtx);
180}
181
182static void
183zbbus_intr_unmask(void *arg)
184{
185	uint64_t mask;
186	int irq;
187
188	irq = (uintptr_t)arg;
189
190	mtx_lock_spin(&zbbus_intr_mtx);
191
192	mask = sb_read_intsrc_mask(0);
193	mask &= ~hardint_to_intsrc_mask[irq];
194	sb_write_intsrc_mask(0, mask);
195
196	mtx_unlock_spin(&zbbus_intr_mtx);
197}
198
199struct zbbus_devinfo {
200	struct resource_list resources;
201};
202
203static MALLOC_DEFINE(M_ZBBUSDEV, "zbbusdev", "zbbusdev");
204
205static int
206zbbus_probe(device_t dev)
207{
208
209	device_set_desc(dev, "Broadcom/Sibyte ZBbus");
210	return (BUS_PROBE_NOWILDCARD);
211}
212
213static int
214zbbus_attach(device_t dev)
215{
216
217	if (bootverbose) {
218		device_printf(dev, "attached.\n");
219	}
220
221	cpu_set_hardintr_mask_func(zbbus_intr_mask);
222	cpu_set_hardintr_unmask_func(zbbus_intr_unmask);
223
224	bus_generic_probe(dev);
225	bus_enumerate_hinted_children(dev);
226	bus_generic_attach(dev);
227
228	return (0);
229}
230
231static void
232zbbus_hinted_child(device_t bus, const char *dname, int dunit)
233{
234	device_t child;
235	long maddr, msize;
236	int err, irq;
237
238	if (resource_disabled(dname, dunit))
239		return;
240
241	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
242	if (child == NULL) {
243		panic("zbbus: could not add child %s unit %d\n", dname, dunit);
244	}
245
246	if (bootverbose)
247		device_printf(bus, "Adding hinted child %s%d\n", dname, dunit);
248
249	/*
250	 * Assign any pre-defined resources to the child.
251	 */
252	if (resource_long_value(dname, dunit, "msize", &msize) == 0 &&
253	    resource_long_value(dname, dunit, "maddr", &maddr) == 0) {
254		if (bootverbose) {
255			device_printf(bus, "Assigning memory resource "
256					   "0x%0lx/%ld to child %s%d\n",
257					   maddr, msize, dname, dunit);
258		}
259		err = bus_set_resource(child, SYS_RES_MEMORY, 0, maddr, msize);
260		if (err) {
261			device_printf(bus, "Unable to set memory resource "
262					   "0x%0lx/%ld for child %s%d: %d\n",
263					   maddr, msize, dname, dunit, err);
264		}
265	}
266
267	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
268		if (bootverbose) {
269			device_printf(bus, "Assigning irq resource %d to "
270					   "child %s%d\n", irq, dname, dunit);
271		}
272		err = bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1);
273		if (err) {
274			device_printf(bus, "Unable to set irq resource %d"
275					   "for child %s%d: %d\n",
276					   irq, dname, dunit, err);
277		}
278	}
279}
280
281static struct resource *
282zbbus_alloc_resource(device_t bus, device_t child, int type, int *rid,
283		     u_long start, u_long end, u_long count, u_int flags)
284{
285	struct resource *res;
286	int intrnum, intsrc, isdefault;
287	struct resource_list *rl;
288	struct resource_list_entry *rle;
289	struct zbbus_devinfo *dinfo;
290
291	isdefault = (start == 0UL && end == ~0UL && count == 1);
292
293	/*
294	 * Our direct child is asking for a default resource allocation.
295	 */
296	if (device_get_parent(child) == bus) {
297		dinfo = device_get_ivars(child);
298		rl = &dinfo->resources;
299		rle = resource_list_find(rl, type, *rid);
300		if (rle) {
301			if (rle->res)
302				panic("zbbus_alloc_resource: resource is busy");
303			if (isdefault) {
304				start = rle->start;
305				count = ulmax(count, rle->count);
306				end = ulmax(rle->end, start + count - 1);
307			}
308		} else {
309			if (isdefault) {
310				/*
311				 * Our child is requesting a default
312				 * resource allocation but we don't have the
313				 * 'type/rid' tuple in the resource list.
314				 *
315				 * We have to fail the resource allocation.
316				 */
317				return (NULL);
318			} else {
319				/*
320				 * The child is requesting a non-default
321				 * resource. We just pass the request up
322				 * to our parent. If the resource allocation
323				 * succeeds we will create a resource list
324				 * entry corresponding to that resource.
325				 */
326			}
327		}
328	} else {
329		rl = NULL;
330		rle = NULL;
331	}
332
333	/*
334	 * nexus doesn't know about the interrupt mapper and only wants to
335	 * see the hard irq numbers [0-6]. We translate from the interrupt
336	 * source presented to the mapper to the interrupt number presented
337	 * to the cpu.
338	 */
339	if ((count == 1) && (type == SYS_RES_IRQ)) {
340		intsrc = start;
341		intrnum = sb_route_intsrc(intsrc);
342		start = end = intrnum;
343	} else {
344		intsrc = -1;		/* satisfy gcc */
345		intrnum = -1;
346	}
347
348	res = bus_generic_alloc_resource(bus, child, type, rid,
349 					 start, end, count, flags);
350
351	/*
352	 * Keep track of the input into the interrupt mapper that maps
353	 * to the resource allocated by 'child' with resource id 'rid'.
354	 *
355	 * If we don't record the mapping here then we won't be able to
356	 * locate the interrupt source when bus_setup_intr(child,rid) is
357	 * called.
358	 */
359	if (res != NULL && intrnum != -1)
360		sb_intmap_add(intrnum, child, rman_get_rid(res), intsrc);
361
362	/*
363	 * If a non-default resource allocation by our child was successful
364	 * then keep track of the resource in the resource list associated
365	 * with the child.
366	 */
367	if (res != NULL && rle == NULL && device_get_parent(child) == bus) {
368		resource_list_add(rl, type, *rid, start, end, count);
369		rle = resource_list_find(rl, type, *rid);
370		if (rle == NULL)
371			panic("zbbus_alloc_resource: cannot find resource");
372	}
373
374	if (rle != NULL) {
375		KASSERT(device_get_parent(child) == bus,
376			("rle should be NULL for passthru device"));
377		rle->res = res;
378		if (rle->res) {
379			rle->start = rman_get_start(rle->res);
380			rle->end = rman_get_end(rle->res);
381			rle->count = count;
382		}
383	}
384
385	return (res);
386}
387
388static int
389zbbus_setup_intr(device_t dev, device_t child, struct resource *irq, int flags,
390		 driver_filter_t *filter, driver_intr_t *intr, void *arg,
391		 void **cookiep)
392{
393	int error;
394
395	error = bus_generic_setup_intr(dev, child, irq, flags,
396				       filter, intr, arg, cookiep);
397	if (error == 0)
398		sb_intmap_activate(rman_get_start(irq), child,
399				   rman_get_rid(irq));
400
401	return (error);
402}
403
404static device_t
405zbbus_add_child(device_t bus, u_int order, const char *name, int unit)
406{
407	device_t child;
408	struct zbbus_devinfo *dinfo;
409
410	child = device_add_child_ordered(bus, order, name, unit);
411	if (child != NULL) {
412		dinfo = malloc(sizeof(struct zbbus_devinfo), M_ZBBUSDEV,
413			       M_WAITOK | M_ZERO);
414		resource_list_init(&dinfo->resources);
415		device_set_ivars(child, dinfo);
416	}
417
418	return (child);
419}
420
421static struct resource_list *
422zbbus_get_resource_list(device_t dev, device_t child)
423{
424	struct zbbus_devinfo *dinfo = device_get_ivars(child);
425
426	return (&dinfo->resources);
427}
428
429static device_method_t zbbus_methods[] ={
430	/* Device interface */
431	DEVMETHOD(device_probe,		zbbus_probe),
432	DEVMETHOD(device_attach,	zbbus_attach),
433	DEVMETHOD(device_detach,	bus_generic_detach),
434	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
435	DEVMETHOD(device_suspend,	bus_generic_suspend),
436	DEVMETHOD(device_resume,	bus_generic_resume),
437
438	/* Bus interface */
439	DEVMETHOD(bus_alloc_resource,	zbbus_alloc_resource),
440	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
441	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
442	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
443	DEVMETHOD(bus_get_resource_list,zbbus_get_resource_list),
444	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
445	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
446	DEVMETHOD(bus_delete_resource,	bus_generic_rl_delete_resource),
447	DEVMETHOD(bus_setup_intr,	zbbus_setup_intr),
448	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
449	DEVMETHOD(bus_add_child,	zbbus_add_child),
450	DEVMETHOD(bus_hinted_child,	zbbus_hinted_child),
451
452	{ 0, 0 }
453};
454
455static driver_t zbbus_driver = {
456	"zbbus",
457	zbbus_methods
458};
459
460static devclass_t zbbus_devclass;
461
462DRIVER_MODULE(zbbus, nexus, zbbus_driver, zbbus_devclass, 0, 0);
463