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/param.h> 36 #include <sys/systm.h> 37 #include <sys/bus.h> 38 #include <sys/kernel.h> 39 #include <sys/module.h> 40 #include <sys/rman.h> 41 42 #include <dev/ofw/ofw_bus.h> 43 #include <dev/ofw/ofw_bus_subr.h> 44 #include <dev/ofw/openfirm.h> 45 #include <dev/fdt/simplebus.h> 46 47 #include <machine/bus.h> 48 #include <machine/resource.h> 49 50 /* 51 * The ofwbus (which is a pseudo-bus actually) iterates over the nodes that 52 * hang from the Open Firmware root node and adds them as devices to this bus 53 * (except some special nodes which are excluded) so that drivers can be 54 * attached to them. There should be only one ofwbus in the system, added 55 * directly as a child of nexus0. 56 */ 57 58 static device_probe_t ofwbus_probe; 59 static device_attach_t ofwbus_attach; 60 static bus_alloc_resource_t ofwbus_alloc_resource; 61 static bus_release_resource_t ofwbus_release_resource; 62 63 static device_method_t ofwbus_methods[] = { 64 /* Device interface */ 65 DEVMETHOD(device_probe, ofwbus_probe), 66 DEVMETHOD(device_attach, ofwbus_attach), 67 68 /* Bus interface */ 69 DEVMETHOD(bus_alloc_resource, ofwbus_alloc_resource), 70 DEVMETHOD(bus_adjust_resource, bus_generic_adjust_resource), 71 DEVMETHOD(bus_release_resource, ofwbus_release_resource), 72 73 DEVMETHOD_END 74 }; 75 76 DEFINE_CLASS_1(ofwbus, ofwbus_driver, ofwbus_methods, 77 sizeof(struct simplebus_softc), simplebus_driver); 78 EARLY_DRIVER_MODULE(ofwbus, nexus, ofwbus_driver, 0, 0, 79 BUS_PASS_BUS + BUS_PASS_ORDER_MIDDLE); 80 MODULE_VERSION(ofwbus, 1); 81 82 static int 83 ofwbus_probe(device_t dev) 84 { 85 86 if (OF_peer(0) == 0) 87 return (ENXIO); 88 89 /* Only one instance of ofwbus. */ 90 if (device_get_unit(dev) != 0) 91 panic("ofwbus added with non-zero unit number: %d\n", 92 device_get_unit(dev)); 93 94 device_set_desc(dev, "Open Firmware Device Tree"); 95 return (BUS_PROBE_NOWILDCARD); 96 } 97 98 static int 99 ofwbus_attach(device_t dev) 100 { 101 phandle_t node; 102 103 node = OF_peer(0); 104 105 /* 106 * If no Open Firmware, bail early 107 */ 108 if (node == -1) 109 return (ENXIO); 110 111 /* 112 * ofwbus bus starts on unamed node in FDT, so we cannot make 113 * ofw_bus_devinfo from it. Pass node to simplebus_init directly. 114 */ 115 simplebus_init(dev, node); 116 117 /* 118 * Allow devices to identify. 119 */ 120 bus_generic_probe(dev); 121 122 /* 123 * Now walk the OFW tree and attach top-level devices. 124 */ 125 for (node = OF_child(node); node > 0; node = OF_peer(node)) 126 simplebus_add_device(dev, node, 0, NULL, -1, NULL); 127 128 return (bus_generic_attach(dev)); 129 } 130 131 static struct resource * 132 ofwbus_alloc_resource(device_t bus, device_t child, int type, int *rid, 133 rman_res_t start, rman_res_t end, rman_res_t count, u_int flags) 134 { 135 struct resource *rv; 136 struct resource_list_entry *rle; 137 bool isdefault, passthrough; 138 139 isdefault = RMAN_IS_DEFAULT_RANGE(start, end); 140 passthrough = (device_get_parent(child) != bus); 141 rle = NULL; 142 if (!passthrough && isdefault) { 143 rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child), 144 type, *rid); 145 if (rle == NULL) { 146 if (bootverbose) 147 device_printf(bus, "no default resources for " 148 "rid = %d, type = %d\n", *rid, type); 149 return (NULL); 150 } 151 start = rle->start; 152 count = ummax(count, rle->count); 153 end = ummax(rle->end, start + count - 1); 154 } 155 156 /* Let nexus handle the allocation. */ 157 rv = bus_generic_alloc_resource(bus, child, type, rid, start, end, 158 count, flags); 159 if (rv == NULL) 160 return (NULL); 161 162 if (!passthrough && rle != NULL) { 163 rle->res = rv; 164 rle->start = rman_get_start(rv); 165 rle->end = rman_get_end(rv); 166 rle->count = rle->end - rle->start + 1; 167 } 168 169 return (rv); 170 } 171 172 static int 173 ofwbus_release_resource(device_t bus, device_t child, struct resource *r) 174 { 175 struct resource_list_entry *rle; 176 bool passthrough; 177 178 passthrough = (device_get_parent(child) != bus); 179 if (!passthrough) { 180 /* Clean resource list entry */ 181 rle = resource_list_find(BUS_GET_RESOURCE_LIST(bus, child), 182 rman_get_type(r), rman_get_rid(r)); 183 if (rle != NULL) 184 rle->res = NULL; 185 } 186 187 /* Let nexus handle the release. */ 188 return (bus_generic_release_resource(bus, child, r)); 189 } 190