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/module.h> 43 #include <sys/rman.h> 44 45 #include <dev/ofw/ofw_bus.h> 46 #include <dev/ofw/ofw_bus_subr.h> 47 #include <dev/ofw/openfirm.h> 48 #include <dev/fdt/simplebus.h> 49 50 #include <machine/bus.h> 51 #include <machine/resource.h> 52 53 /* 54 * The ofwbus (which is a pseudo-bus actually) iterates over the nodes that 55 * hang from the Open Firmware root node and adds them as devices to this bus 56 * (except some special nodes which are excluded) so that drivers can be 57 * attached to them. There should be only one ofwbus in the system, added 58 * directly as a child of nexus0. 59 */ 60 61 static device_probe_t ofwbus_probe; 62 static device_attach_t ofwbus_attach; 63 static bus_alloc_resource_t ofwbus_alloc_resource; 64 static bus_release_resource_t ofwbus_release_resource; 65 66 static device_method_t ofwbus_methods[] = { 67 /* Device interface */ 68 DEVMETHOD(device_probe, ofwbus_probe), 69 DEVMETHOD(device_attach, ofwbus_attach), 70 71 /* Bus interface */ 72 DEVMETHOD(bus_alloc_resource, ofwbus_alloc_resource), 73 DEVMETHOD(bus_adjust_resource, bus_generic_adjust_resource), 74 DEVMETHOD(bus_release_resource, ofwbus_release_resource), 75 76 DEVMETHOD_END 77 }; 78 79 DEFINE_CLASS_1(ofwbus, ofwbus_driver, ofwbus_methods, 80 sizeof(struct simplebus_softc), simplebus_driver); 81 EARLY_DRIVER_MODULE(ofwbus, nexus, ofwbus_driver, 0, 0, 82 BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE); 83 MODULE_VERSION(ofwbus, 1); 84 85 static int 86 ofwbus_probe(device_t dev) 87 { 88 89 if (OF_peer(0) == 0) 90 return (ENXIO); 91 92 /* Only one instance of ofwbus. */ 93 if (device_get_unit(dev) != 0) 94 panic("ofwbus added with non-zero unit number: %d\n", 95 device_get_unit(dev)); 96 97 device_set_desc(dev, "Open Firmware Device Tree"); 98 return (BUS_PROBE_NOWILDCARD); 99 } 100 101 static int 102 ofwbus_attach(device_t dev) 103 { 104 phandle_t node; 105 106 node = OF_peer(0); 107 108 /* 109 * If no Open Firmware, bail early 110 */ 111 if (node == -1) 112 return (ENXIO); 113 114 /* 115 * ofwbus bus starts on unamed node in FDT, so we cannot make 116 * ofw_bus_devinfo from it. Pass node to simplebus_init directly. 117 */ 118 simplebus_init(dev, node); 119 120 /* 121 * Allow devices to identify. 122 */ 123 bus_generic_probe(dev); 124 125 /* 126 * Now walk the OFW tree and attach top-level devices. 127 */ 128 for (node = OF_child(node); node > 0; node = OF_peer(node)) 129 simplebus_add_device(dev, node, 0, NULL, -1, NULL); 130 131 return (bus_generic_attach(dev)); 132 } 133 134 static struct resource * 135 ofwbus_alloc_resource(device_t bus, device_t child, int type, int *rid, 136 rman_res_t start, rman_res_t end, rman_res_t count, u_int flags) 137 { 138 struct resource *rv; 139 struct resource_list_entry *rle; 140 bool isdefault, passthrough; 141 142 isdefault = RMAN_IS_DEFAULT_RANGE(start, end); 143 passthrough = (device_get_parent(child) != bus); 144 rle = NULL; 145 if (!passthrough && isdefault) { 146 rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child), 147 type, *rid); 148 if (rle == NULL) { 149 if (bootverbose) 150 device_printf(bus, "no default resources for " 151 "rid = %d, type = %d\n", *rid, type); 152 return (NULL); 153 } 154 start = rle->start; 155 count = ummax(count, rle->count); 156 end = ummax(rle->end, start + count - 1); 157 } 158 159 /* Let nexus handle the allocation. */ 160 rv = bus_generic_alloc_resource(bus, child, type, rid, start, end, 161 count, flags); 162 if (rv == NULL) 163 return (NULL); 164 165 if (!passthrough && rle != NULL) { 166 rle->res = rv; 167 rle->start = rman_get_start(rv); 168 rle->end = rman_get_end(rv); 169 rle->count = rle->end - rle->start + 1; 170 } 171 172 return (rv); 173 } 174 175 static int 176 ofwbus_release_resource(device_t bus, device_t child, int type, 177 int rid, struct resource *r) 178 { 179 struct resource_list_entry *rle; 180 bool passthrough; 181 182 passthrough = (device_get_parent(child) != bus); 183 if (!passthrough) { 184 /* Clean resource list entry */ 185 rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child), 186 type, rid); 187 if (rle != NULL) 188 rle->res = NULL; 189 } 190 191 /* Let nexus handle the release. */ 192 return (bus_generic_release_resource(bus, child, type, rid, r)); 193 } 194