xref: /freebsd/sys/dev/amdsmn/amdsmn.c (revision da3086df1863e9aed45eb14e265c306f8bb27d80)
1 /*-
2  * Copyright (c) 2017 Conrad Meyer <cem@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
18  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
20  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
22  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
23  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24  * POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 /*
28  * Driver for the AMD Family 17h CPU System Management Network.
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/bus.h>
36 #include <sys/conf.h>
37 #include <sys/lock.h>
38 #include <sys/kernel.h>
39 #include <sys/module.h>
40 #include <sys/mutex.h>
41 #include <sys/sysctl.h>
42 #include <sys/systm.h>
43 
44 #include <machine/cpufunc.h>
45 #include <machine/md_var.h>
46 #include <machine/specialreg.h>
47 
48 #include <dev/pci/pcivar.h>
49 #include <x86/pci_cfgreg.h>
50 
51 #include <dev/amdsmn/amdsmn.h>
52 
53 #define	SMN_ADDR_REG	0x60
54 #define	SMN_DATA_REG	0x64
55 
56 struct amdsmn_softc {
57 	struct mtx smn_lock;
58 };
59 
60 static struct pciid {
61 	uint32_t	device_id;
62 } amdsmn_ids[] = {
63 	{ 0x14501022 },
64 };
65 
66 /*
67  * Device methods.
68  */
69 static void 	amdsmn_identify(driver_t *driver, device_t parent);
70 static int	amdsmn_probe(device_t dev);
71 static int	amdsmn_attach(device_t dev);
72 static int	amdsmn_detach(device_t dev);
73 
74 static device_method_t amdsmn_methods[] = {
75 	/* Device interface */
76 	DEVMETHOD(device_identify,	amdsmn_identify),
77 	DEVMETHOD(device_probe,		amdsmn_probe),
78 	DEVMETHOD(device_attach,	amdsmn_attach),
79 	DEVMETHOD(device_detach,	amdsmn_detach),
80 	DEVMETHOD_END
81 };
82 
83 static driver_t amdsmn_driver = {
84 	"amdsmn",
85 	amdsmn_methods,
86 	sizeof(struct amdsmn_softc),
87 };
88 
89 static devclass_t amdsmn_devclass;
90 DRIVER_MODULE(amdsmn, hostb, amdsmn_driver, amdsmn_devclass, NULL, NULL);
91 MODULE_VERSION(amdsmn, 1);
92 
93 static bool
94 amdsmn_match(device_t parent)
95 {
96 	uint32_t devid;
97 	size_t i;
98 
99 	devid = pci_get_devid(parent);
100 	for (i = 0; i < nitems(amdsmn_ids); i++)
101 		if (amdsmn_ids[i].device_id == devid)
102 			return (true);
103 	return (false);
104 }
105 
106 static void
107 amdsmn_identify(driver_t *driver, device_t parent)
108 {
109 	device_t child;
110 
111 	/* Make sure we're not being doubly invoked. */
112 	if (device_find_child(parent, "amdsmn", -1) != NULL)
113 		return;
114 	if (!amdsmn_match(parent))
115 		return;
116 
117 	child = device_add_child(parent, "amdsmn", -1);
118 	if (child == NULL)
119 		device_printf(parent, "add amdsmn child failed\n");
120 }
121 
122 static int
123 amdsmn_probe(device_t dev)
124 {
125 	uint32_t family;
126 
127 	if (resource_disabled("amdsmn", 0))
128 		return (ENXIO);
129 	if (!amdsmn_match(device_get_parent(dev)))
130 		return (ENXIO);
131 
132 	family = CPUID_TO_FAMILY(cpu_id);
133 
134 	switch (family) {
135 	case 0x17:
136 		break;
137 	default:
138 		return (ENXIO);
139 	}
140 	device_set_desc(dev, "AMD Family 17h System Management Network");
141 
142 	return (BUS_PROBE_GENERIC);
143 }
144 
145 static int
146 amdsmn_attach(device_t dev)
147 {
148 	struct amdsmn_softc *sc = device_get_softc(dev);
149 
150 	mtx_init(&sc->smn_lock, "SMN mtx", "SMN", MTX_DEF);
151 	return (0);
152 }
153 
154 int
155 amdsmn_detach(device_t dev)
156 {
157 	struct amdsmn_softc *sc = device_get_softc(dev);
158 
159 	mtx_destroy(&sc->smn_lock);
160 	return (0);
161 }
162 
163 int
164 amdsmn_read(device_t dev, uint32_t addr, uint32_t *value)
165 {
166 	struct amdsmn_softc *sc = device_get_softc(dev);
167 	device_t parent;
168 
169 	parent = device_get_parent(dev);
170 
171 	mtx_lock(&sc->smn_lock);
172 	pci_write_config(parent, SMN_ADDR_REG, addr, 4);
173 	*value = pci_read_config(parent, SMN_DATA_REG, 4);
174 	mtx_unlock(&sc->smn_lock);
175 
176 	return (0);
177 }
178 
179 int
180 amdsmn_write(device_t dev, uint32_t addr, uint32_t value)
181 {
182 	struct amdsmn_softc *sc = device_get_softc(dev);
183 	device_t parent;
184 
185 	parent = device_get_parent(dev);
186 
187 	mtx_lock(&sc->smn_lock);
188 	pci_write_config(parent, SMN_ADDR_REG, addr, 4);
189 	pci_write_config(parent, SMN_DATA_REG, value, 4);
190 	mtx_unlock(&sc->smn_lock);
191 
192 	return (0);
193 }
194