ofwbus.c revision 282480
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: head/sys/dev/ofw/ofwbus.c 282480 2015-05-05 11:13:16Z andrew $");
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
66struct 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__
73static device_identify_t ofwbus_identify;
74#endif
75static device_probe_t ofwbus_probe;
76static device_attach_t ofwbus_attach;
77static bus_alloc_resource_t ofwbus_alloc_resource;
78static bus_adjust_resource_t ofwbus_adjust_resource;
79static bus_release_resource_t ofwbus_release_resource;
80
81static 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
97DEFINE_CLASS_1(ofwbus, ofwbus_driver, ofwbus_methods,
98    sizeof(struct ofwbus_softc), simplebus_driver);
99static devclass_t ofwbus_devclass;
100EARLY_DRIVER_MODULE(ofwbus, nexus, ofwbus_driver, ofwbus_devclass, 0, 0,
101    BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE);
102MODULE_VERSION(ofwbus, 1);
103
104#ifndef __aarch64__
105static void
106ofwbus_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
118static int
119ofwbus_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
131static int
132ofwbus_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
179static struct resource *
180ofwbus_alloc_resource(device_t bus, device_t child, int type, int *rid,
181    u_long start, u_long end, u_long 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 = (start == 0UL && end == ~0UL);
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 = ulmax(count, rle->count);
204		end = ulmax(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
240static int
241ofwbus_adjust_resource(device_t bus, device_t child __unused, int type,
242    struct resource *r, u_long start, u_long 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
269static int
270ofwbus_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 error;
275
276	/* Clean resource list entry */
277	rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child), type, rid);
278	if (rle != NULL)
279		rle->res = NULL;
280
281	if ((rman_get_flags(r) & RF_ACTIVE) != 0) {
282		error = bus_deactivate_resource(child, type, rid, r);
283		if (error)
284			return (error);
285	}
286	return (rman_release_resource(r));
287}
288