xref: /freebsd/sys/dev/ofw/ofwbus.c (revision 716fd348)
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 #ifdef INTRNG
47 #include <sys/intr.h>
48 #endif
49 
50 #include <vm/vm.h>
51 #include <vm/pmap.h>
52 
53 #include <dev/ofw/ofw_bus.h>
54 #include <dev/ofw/ofw_bus_subr.h>
55 #include <dev/ofw/openfirm.h>
56 #include <dev/fdt/simplebus.h>
57 
58 #include <machine/bus.h>
59 #include <machine/resource.h>
60 
61 /*
62  * The ofwbus (which is a pseudo-bus actually) iterates over the nodes that
63  * hang from the Open Firmware root node and adds them as devices to this bus
64  * (except some special nodes which are excluded) so that drivers can be
65  * attached to them.
66  *
67  */
68 
69 struct ofwbus_softc {
70 	struct simplebus_softc simplebus_sc;
71 	struct rman	sc_intr_rman;
72 	struct rman	sc_mem_rman;
73 };
74 
75 #ifndef __aarch64__
76 static device_identify_t ofwbus_identify;
77 #endif
78 static device_probe_t ofwbus_probe;
79 static device_attach_t ofwbus_attach;
80 static bus_alloc_resource_t ofwbus_alloc_resource;
81 static bus_adjust_resource_t ofwbus_adjust_resource;
82 static bus_release_resource_t ofwbus_release_resource;
83 
84 static device_method_t ofwbus_methods[] = {
85 	/* Device interface */
86 #ifndef __aarch64__
87 	DEVMETHOD(device_identify,	ofwbus_identify),
88 #endif
89 	DEVMETHOD(device_probe,		ofwbus_probe),
90 	DEVMETHOD(device_attach,	ofwbus_attach),
91 
92 	/* Bus interface */
93 	DEVMETHOD(bus_alloc_resource,	ofwbus_alloc_resource),
94 	DEVMETHOD(bus_adjust_resource,	ofwbus_adjust_resource),
95 	DEVMETHOD(bus_release_resource,	ofwbus_release_resource),
96 
97 	DEVMETHOD_END
98 };
99 
100 DEFINE_CLASS_1(ofwbus, ofwbus_driver, ofwbus_methods,
101     sizeof(struct ofwbus_softc), simplebus_driver);
102 EARLY_DRIVER_MODULE(ofwbus, nexus, ofwbus_driver, 0, 0,
103     BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
104 MODULE_VERSION(ofwbus, 1);
105 
106 #ifndef __aarch64__
107 static void
108 ofwbus_identify(driver_t *driver, device_t parent)
109 {
110 
111 	/* Check if Open Firmware has been instantiated */
112 	if (OF_peer(0) == 0)
113 		return;
114 
115 	if (device_find_child(parent, "ofwbus", -1) == NULL)
116 		BUS_ADD_CHILD(parent, 0, "ofwbus", -1);
117 }
118 #endif
119 
120 static int
121 ofwbus_probe(device_t dev)
122 {
123 
124 #ifdef __aarch64__
125 	if (OF_peer(0) == 0)
126 		return (ENXIO);
127 #endif
128 
129 	device_set_desc(dev, "Open Firmware Device Tree");
130 	return (BUS_PROBE_NOWILDCARD);
131 }
132 
133 static int
134 ofwbus_attach(device_t dev)
135 {
136 	struct ofwbus_softc *sc;
137 	phandle_t node;
138 	struct ofw_bus_devinfo obd;
139 
140 	sc = device_get_softc(dev);
141 
142 	node = OF_peer(0);
143 
144 	/*
145 	 * If no Open Firmware, bail early
146 	 */
147 	if (node == -1)
148 		return (ENXIO);
149 
150 	/*
151 	 * ofwbus bus starts on unamed node in FDT, so we cannot make
152 	 * ofw_bus_devinfo from it. Pass node to simplebus_init directly.
153 	 */
154 	simplebus_init(dev, node);
155 	sc->sc_intr_rman.rm_type = RMAN_ARRAY;
156 	sc->sc_intr_rman.rm_descr = "Interrupts";
157 	sc->sc_mem_rman.rm_type = RMAN_ARRAY;
158 	sc->sc_mem_rman.rm_descr = "Device Memory";
159 	if (rman_init(&sc->sc_intr_rman) != 0 ||
160 	    rman_init(&sc->sc_mem_rman) != 0 ||
161 	    rman_manage_region(&sc->sc_intr_rman, 0, ~0) != 0 ||
162 	    rman_manage_region(&sc->sc_mem_rman, 0, BUS_SPACE_MAXADDR) != 0)
163 		panic("%s: failed to set up rmans.", __func__);
164 
165 	/*
166 	 * Allow devices to identify.
167 	 */
168 	bus_generic_probe(dev);
169 
170 	/*
171 	 * Now walk the OFW tree and attach top-level devices.
172 	 */
173 	for (node = OF_child(node); node > 0; node = OF_peer(node)) {
174 		if (ofw_bus_gen_setup_devinfo(&obd, node) != 0)
175 			continue;
176 		simplebus_add_device(dev, node, 0, NULL, -1, NULL);
177 	}
178 	return (bus_generic_attach(dev));
179 }
180 
181 static struct resource *
182 ofwbus_alloc_resource(device_t bus, device_t child, int type, int *rid,
183     rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
184 {
185 	struct ofwbus_softc *sc;
186 	struct rman *rm;
187 	struct resource *rv;
188 	struct resource_list_entry *rle;
189 	int isdefault, passthrough;
190 
191 	isdefault = RMAN_IS_DEFAULT_RANGE(start, end);
192 	passthrough = (device_get_parent(child) != bus);
193 	sc = device_get_softc(bus);
194 	rle = NULL;
195 	if (!passthrough && isdefault) {
196 		rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child),
197 		    type, *rid);
198 		if (rle == NULL) {
199 			if (bootverbose)
200 				device_printf(bus, "no default resources for "
201 				    "rid = %d, type = %d\n", *rid, type);
202 			return (NULL);
203 		}
204 		start = rle->start;
205 		count = ummax(count, rle->count);
206 		end = ummax(rle->end, start + count - 1);
207 	}
208 
209 	switch (type) {
210 	case SYS_RES_IRQ:
211 		rm = &sc->sc_intr_rman;
212 		break;
213 	case SYS_RES_MEMORY:
214 		rm = &sc->sc_mem_rman;
215 		break;
216 	default:
217 		return (NULL);
218 	}
219 
220 	rv = rman_reserve_resource(rm, start, end, count, flags & ~RF_ACTIVE,
221 	    child);
222 	if (rv == NULL)
223 		return (NULL);
224 	rman_set_rid(rv, *rid);
225 
226 	if ((flags & RF_ACTIVE) != 0 && bus_activate_resource(child, type,
227 	    *rid, rv) != 0) {
228 		rman_release_resource(rv);
229 		return (NULL);
230 	}
231 
232 	if (!passthrough && rle != NULL) {
233 		rle->res = rv;
234 		rle->start = rman_get_start(rv);
235 		rle->end = rman_get_end(rv);
236 		rle->count = rle->end - rle->start + 1;
237 	}
238 
239 	return (rv);
240 }
241 
242 static int
243 ofwbus_adjust_resource(device_t bus, device_t child __unused, int type,
244     struct resource *r, rman_res_t start, rman_res_t end)
245 {
246 	struct ofwbus_softc *sc;
247 	struct rman *rm;
248 	device_t ofwbus;
249 
250 	ofwbus = bus;
251 	while (strcmp(device_get_name(device_get_parent(ofwbus)), "root") != 0)
252 		ofwbus = device_get_parent(ofwbus);
253 	sc = device_get_softc(ofwbus);
254 	switch (type) {
255 	case SYS_RES_IRQ:
256 		rm = &sc->sc_intr_rman;
257 		break;
258 	case SYS_RES_MEMORY:
259 		rm = &sc->sc_mem_rman;
260 		break;
261 	default:
262 		return (EINVAL);
263 	}
264 	if (rm == NULL)
265 		return (ENXIO);
266 	if (rman_is_region_manager(r, rm) == 0)
267 		return (EINVAL);
268 	return (rman_adjust_resource(r, start, end));
269 }
270 
271 static int
272 ofwbus_release_resource(device_t bus, device_t child, int type,
273     int rid, struct resource *r)
274 {
275 	struct resource_list_entry *rle;
276 	int passthrough;
277 	int error;
278 
279 	passthrough = (device_get_parent(child) != bus);
280 	if (!passthrough) {
281 		/* Clean resource list entry */
282 		rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child),
283 		    type, rid);
284 		if (rle != NULL)
285 			rle->res = NULL;
286 	}
287 
288 	if ((rman_get_flags(r) & RF_ACTIVE) != 0) {
289 		error = bus_deactivate_resource(child, type, rid, r);
290 		if (error)
291 			return (error);
292 	}
293 	return (rman_release_resource(r));
294 }
295