1 /*-
2 * Copyright (C) 2018 Breno Leitao
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
17 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
18 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
19 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
20 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
21 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
22 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25 #include <sys/cdefs.h>
26 __FBSDID("$FreeBSD$");
27
28 #include <sys/param.h>
29 #include <sys/kernel.h>
30 #include <sys/systm.h>
31 #include <sys/module.h>
32 #include <sys/types.h>
33 #include <sys/proc.h>
34
35 #include <vm/vm.h>
36 #include <vm/pmap.h>
37
38 #include <machine/bus.h>
39
40 #include <dev/ofw/openfirm.h>
41 #include <dev/ofw/ofw_bus.h>
42 #include <dev/ofw/ofw_bus_subr.h>
43
44 #include "opt_md.h"
45
46 #ifdef MD_ROOT_MEM
47 extern u_char *mfs_root;
48 extern uint32_t mfs_root_size;
49 #else
50 #warning "MD_ROOT_MEM should be set to use ofw initrd as a md device"
51 #endif
52
53 /* bus entry points */
54 static int ofw_initrd_probe(device_t dev);
55 static int ofw_initrd_attach(device_t dev);
56 static void ofw_initrd_identify(driver_t *driver, device_t parent);
57
58 struct ofw_initrd_softc {
59 device_t sc_dev;
60 vm_paddr_t start;
61 vm_paddr_t end;
62 };
63
64 static int
ofw_initrd_probe(device_t dev)65 ofw_initrd_probe(device_t dev)
66 {
67 phandle_t chosen;
68
69 /* limit this device to one unit */
70 if (device_get_unit(dev) != 0)
71 return (ENXIO);
72
73 chosen = OF_finddevice("/chosen");
74 if (chosen <= 0) {
75 return (ENXIO);
76 }
77
78 if (!OF_hasprop(chosen, "linux,initrd-start") ||
79 !OF_hasprop(chosen, "linux,initrd-end"))
80 return (ENXIO);
81
82 device_set_desc(dev, "OFW initrd memregion loader");
83 return (BUS_PROBE_DEFAULT);
84 }
85
86 static int
ofw_initrd_attach(device_t dev)87 ofw_initrd_attach(device_t dev)
88 {
89 struct ofw_initrd_softc *sc;
90 vm_paddr_t start, end;
91 phandle_t chosen;
92 pcell_t cell[2];
93 ssize_t size;
94
95 sc = device_get_softc(dev);
96
97 chosen = OF_finddevice("/chosen");
98 if (chosen <= 0) {
99 device_printf(dev, "/chosen not found\n");
100 return (ENXIO);
101 }
102
103 size = OF_getencprop(chosen, "linux,initrd-start", cell, sizeof(cell));
104 if (size == 4)
105 start = cell[0];
106 else if (size == 8)
107 start = (uint64_t)cell[0] << 32 | cell[1];
108 else {
109 device_printf(dev, "Wrong linux,initrd-start size\n");
110 return (ENXIO);
111 }
112
113 size = OF_getencprop(chosen, "linux,initrd-end", cell, sizeof(cell));
114 if (size == 4)
115 end = cell[0];
116 else if (size == 8)
117 end = (uint64_t)cell[0] << 32 | cell[1];
118 else{
119 device_printf(dev, "Wrong linux,initrd-end size\n");
120 return (ENXIO);
121 }
122
123 if (end - start > 0) {
124 mfs_root = (u_char *) PHYS_TO_DMAP(start);
125 mfs_root_size = end - start;
126
127 return (0);
128 }
129
130 return (ENXIO);
131 }
132
133 static void
ofw_initrd_identify(driver_t * driver,device_t parent)134 ofw_initrd_identify(driver_t *driver, device_t parent)
135 {
136 if (device_find_child(parent, "initrd", -1) != NULL)
137 return;
138
139 if (BUS_ADD_CHILD(parent, 10, "initrd", -1) == NULL)
140 device_printf(parent, "add ofw_initrd child failed\n");
141 }
142
143 static device_method_t ofw_initrd_methods[] = {
144 DEVMETHOD(device_identify, ofw_initrd_identify),
145 DEVMETHOD(device_probe, ofw_initrd_probe),
146 DEVMETHOD(device_attach, ofw_initrd_attach),
147 DEVMETHOD_END
148 };
149
150 static driver_t ofw_initrd_driver = {
151 "ofw_initrd",
152 ofw_initrd_methods,
153 sizeof(struct ofw_initrd_softc)
154 };
155
156 static devclass_t ofw_initrd_devclass;
157
158 DRIVER_MODULE(ofw_initrd, ofwbus, ofw_initrd_driver, ofw_initrd_devclass,
159 NULL, NULL);
160