xref: /freebsd/sys/dev/ofw/ofwbus.c (revision 8ef24a0d4b28fe230e20637f56869cc4148cd2ca)
1 /*-
2  * Copyright 1998 Massachusetts Institute of Technology
3  * Copyright 2001 by Thomas Moestl <tmm@FreeBSD.org>.
4  * Copyright 2006 by Marius Strobl <marius@FreeBSD.org>.
5  * All rights reserved.
6  *
7  * Permission to use, copy, modify, and distribute this software and
8  * its documentation for any purpose and without fee is hereby
9  * granted, provided that both the above copyright notice and this
10  * permission notice appear in all copies, that both the above
11  * copyright notice and this permission notice appear in all
12  * supporting documentation, and that the name of M.I.T. not be used
13  * in advertising or publicity pertaining to distribution of the
14  * software without specific, written prior permission.  M.I.T. makes
15  * no representations about the suitability of this software for any
16  * purpose.  It is provided "as is" without express or implied
17  * warranty.
18  *
19  * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''.  M.I.T. DISCLAIMS
20  * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
21  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
22  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
23  * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
26  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
27  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
28  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
29  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * 	from: FreeBSD: src/sys/i386/i386/nexus.c,v 1.43 2001/02/09
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/bus.h>
41 #include <sys/kernel.h>
42 #include <sys/malloc.h>
43 #include <sys/module.h>
44 #include <sys/pcpu.h>
45 #include <sys/rman.h>
46 
47 #include <vm/vm.h>
48 #include <vm/pmap.h>
49 
50 #include <dev/ofw/ofw_bus.h>
51 #include <dev/ofw/ofw_bus_subr.h>
52 #include <dev/ofw/openfirm.h>
53 #include <dev/fdt/simplebus.h>
54 
55 #include <machine/bus.h>
56 #include <machine/resource.h>
57 
58 /*
59  * The ofwbus (which is a pseudo-bus actually) iterates over the nodes that
60  * hang from the Open Firmware root node and adds them as devices to this bus
61  * (except some special nodes which are excluded) so that drivers can be
62  * attached to them.
63  *
64  */
65 
66 struct ofwbus_softc {
67 	struct simplebus_softc simplebus_sc;
68 	struct rman	sc_intr_rman;
69 	struct rman	sc_mem_rman;
70 };
71 
72 #ifndef __aarch64__
73 static device_identify_t ofwbus_identify;
74 #endif
75 static device_probe_t ofwbus_probe;
76 static device_attach_t ofwbus_attach;
77 static bus_alloc_resource_t ofwbus_alloc_resource;
78 static bus_adjust_resource_t ofwbus_adjust_resource;
79 static bus_release_resource_t ofwbus_release_resource;
80 
81 static device_method_t ofwbus_methods[] = {
82 	/* Device interface */
83 #ifndef __aarch64__
84 	DEVMETHOD(device_identify,	ofwbus_identify),
85 #endif
86 	DEVMETHOD(device_probe,		ofwbus_probe),
87 	DEVMETHOD(device_attach,	ofwbus_attach),
88 
89 	/* Bus interface */
90 	DEVMETHOD(bus_alloc_resource,	ofwbus_alloc_resource),
91 	DEVMETHOD(bus_adjust_resource,	ofwbus_adjust_resource),
92 	DEVMETHOD(bus_release_resource,	ofwbus_release_resource),
93 
94 	DEVMETHOD_END
95 };
96 
97 DEFINE_CLASS_1(ofwbus, ofwbus_driver, ofwbus_methods,
98     sizeof(struct ofwbus_softc), simplebus_driver);
99 static devclass_t ofwbus_devclass;
100 EARLY_DRIVER_MODULE(ofwbus, nexus, ofwbus_driver, ofwbus_devclass, 0, 0,
101     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
102 MODULE_VERSION(ofwbus, 1);
103 
104 #ifndef __aarch64__
105 static void
106 ofwbus_identify(driver_t *driver, device_t parent)
107 {
108 
109 	/* Check if Open Firmware has been instantiated */
110 	if (OF_peer(0) == 0)
111 		return;
112 
113 	if (device_find_child(parent, "ofwbus", -1) == NULL)
114 		BUS_ADD_CHILD(parent, 0, "ofwbus", -1);
115 }
116 #endif
117 
118 static int
119 ofwbus_probe(device_t dev)
120 {
121 
122 #ifdef __aarch64__
123 	if (OF_peer(0) == 0)
124 		return (ENXIO);
125 #endif
126 
127 	device_set_desc(dev, "Open Firmware Device Tree");
128 	return (BUS_PROBE_NOWILDCARD);
129 }
130 
131 static int
132 ofwbus_attach(device_t dev)
133 {
134 	struct ofwbus_softc *sc;
135 	phandle_t node;
136 	struct ofw_bus_devinfo obd;
137 
138 	sc = device_get_softc(dev);
139 
140 	node = OF_peer(0);
141 
142 	/*
143 	 * If no Open Firmware, bail early
144 	 */
145 	if (node == -1)
146 		return (ENXIO);
147 
148 	/*
149 	 * ofwbus bus starts on unamed node in FDT, so we cannot make
150 	 * ofw_bus_devinfo from it. Pass node to simplebus_init directly.
151 	 */
152 	simplebus_init(dev, node);
153 	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
154 	sc->sc_intr_rman.rm_descr = "Interrupts";
155 	sc->sc_mem_rman.rm_type = RMAN_ARRAY;
156 	sc->sc_mem_rman.rm_descr = "Device Memory";
157 	if (rman_init(&sc->sc_intr_rman) != 0 ||
158 	    rman_init(&sc->sc_mem_rman) != 0 ||
159 	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0 ||
160 	    rman_manage_region(&sc->sc_mem_rman, 0, BUS_SPACE_MAXADDR) != 0)
161 		panic("%s: failed to set up rmans.", __func__);
162 
163 	/*
164 	 * Allow devices to identify.
165 	 */
166 	bus_generic_probe(dev);
167 
168 	/*
169 	 * Now walk the OFW tree and attach top-level devices.
170 	 */
171 	for (node = OF_child(node); node > 0; node = OF_peer(node)) {
172 		if (ofw_bus_gen_setup_devinfo(&obd, node) != 0)
173 			continue;
174 		simplebus_add_device(dev, node, 0, NULL, -1, NULL);
175 	}
176 	return (bus_generic_attach(dev));
177 }
178 
179 static struct resource *
180 ofwbus_alloc_resource(device_t bus, device_t child, int type, int *rid,
181     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
182 {
183 	struct ofwbus_softc *sc;
184 	struct rman *rm;
185 	struct resource *rv;
186 	struct resource_list_entry *rle;
187 	int isdefault, passthrough;
188 
189 	isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
190 	passthrough = (device_get_parent(child) != bus);
191 	sc = device_get_softc(bus);
192 	rle = NULL;
193 	if (!passthrough && isdefault) {
194 		rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child),
195 		    type, *rid);
196 		if (rle == NULL) {
197 			if (bootverbose)
198 				device_printf(bus, "no default resources for "
199 				    "rid = %d, type = %d\n", *rid, type);
200 			return (NULL);
201 		}
202 		start = rle->start;
203 		count = ummax(count, rle->count);
204 		end = ummax(rle->end, start + count - 1);
205 	}
206 
207 	switch (type) {
208 	case SYS_RES_IRQ:
209 		rm = &sc->sc_intr_rman;
210 		break;
211 	case SYS_RES_MEMORY:
212 		rm = &sc->sc_mem_rman;
213 		break;
214 	default:
215 		return (NULL);
216 	}
217 
218 	rv = rman_reserve_resource(rm, start, end, count, flags & ~RF_ACTIVE,
219 	    child);
220 	if (rv == NULL)
221 		return (NULL);
222 	rman_set_rid(rv, *rid);
223 
224 	if ((flags & RF_ACTIVE) != 0 && bus_activate_resource(child, type,
225 	    *rid, rv) != 0) {
226 		rman_release_resource(rv);
227 		return (NULL);
228 	}
229 
230 	if (!passthrough && rle != NULL) {
231 		rle->res = rv;
232 		rle->start = rman_get_start(rv);
233 		rle->end = rman_get_end(rv);
234 		rle->count = rle->end - rle->start + 1;
235 	}
236 
237 	return (rv);
238 }
239 
240 static int
241 ofwbus_adjust_resource(device_t bus, device_t child __unused, int type,
242     struct resource *r, rman_res_t start, rman_res_t end)
243 {
244 	struct ofwbus_softc *sc;
245 	struct rman *rm;
246 	device_t ofwbus;
247 
248 	ofwbus = bus;
249 	while (strcmp(device_get_name(device_get_parent(ofwbus)), "root") != 0)
250 		ofwbus = device_get_parent(ofwbus);
251 	sc = device_get_softc(ofwbus);
252 	switch (type) {
253 	case SYS_RES_IRQ:
254 		rm = &sc->sc_intr_rman;
255 		break;
256 	case SYS_RES_MEMORY:
257 		rm = &sc->sc_mem_rman;
258 		break;
259 	default:
260 		return (EINVAL);
261 	}
262 	if (rm == NULL)
263 		return (ENXIO);
264 	if (rman_is_region_manager(r, rm) == 0)
265 		return (EINVAL);
266 	return (rman_adjust_resource(r, start, end));
267 }
268 
269 static int
270 ofwbus_release_resource(device_t bus, device_t child, int type,
271     int rid, struct resource *r)
272 {
273 	struct resource_list_entry *rle;
274 	int passthrough;
275 	int error;
276 
277 	passthrough = (device_get_parent(child) != bus);
278 	if (!passthrough) {
279 		/* Clean resource list entry */
280 		rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child),
281 		    type, rid);
282 		if (rle != NULL)
283 			rle->res = NULL;
284 	}
285 
286 	if ((rman_get_flags(r) & RF_ACTIVE) != 0) {
287 		error = bus_deactivate_resource(child, type, rid, r);
288 		if (error)
289 			return (error);
290 	}
291 	return (rman_release_resource(r));
292 }
293