xref: /freebsd/sys/arm/allwinner/aw_sid.c (revision 4a432d6fa553a2e76645ea6db81b35f52ce839ff)
1 /*-
2  * Copyright (c) 2016 Jared McNeill <jmcneill@invisible.ca>
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 WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
19  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
21  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
22  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 /*
30  * Allwinner secure ID controller
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/endian.h>
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/bus.h>
40 #include <sys/rman.h>
41 #include <sys/kernel.h>
42 #include <sys/lock.h>
43 #include <sys/mutex.h>
44 #include <sys/module.h>
45 #include <sys/sysctl.h>
46 #include <machine/bus.h>
47 
48 #include <dev/ofw/ofw_bus.h>
49 #include <dev/ofw/ofw_bus_subr.h>
50 
51 #include <arm/allwinner/aw_sid.h>
52 
53 /* efuse registers */
54 #define	SID_PRCTL		0x40
55 #define	 SID_PRCTL_OFFSET_MASK	0xff
56 #define	 SID_PRCTL_OFFSET(n)	(((n) & SID_PRCTL_OFFSET_MASK) << 16)
57 #define	 SID_PRCTL_LOCK		(0xac << 8)
58 #define	 SID_PRCTL_READ		(0x01 << 1)
59 #define	 SID_PRCTL_WRITE	(0x01 << 0)
60 #define	SID_PRKEY		0x50
61 #define	SID_RDKEY		0x60
62 
63 #define	SID_SRAM		0x200
64 /* Offsets into efuse space, for convenience */
65 #define	SID_THERMAL_CALIB0_OFF	(0x34)
66 #define	SID_THERMAL_CALIB1_OFF	(0x38)
67 #define	SID_THERMAL_CALIB0	(SID_SRAM + SID_THERMAL_CALIB0_OFF)
68 #define	SID_THERMAL_CALIB1	(SID_SRAM + SID_THERMAL_CALIB1_OFF)
69 
70 #define	ROOT_KEY_SIZE		4
71 
72 struct aw_sid_conf {
73 	bus_size_t	efuse_size;
74 	bus_size_t	rootkey_offset;
75 	bool		has_prctl;
76 	bool		has_thermal;
77 	bool		requires_prctl_read;
78 };
79 
80 static const struct aw_sid_conf a10_conf = {
81 	.efuse_size = 0x10,
82 	.rootkey_offset = 0,
83 };
84 
85 static const struct aw_sid_conf a20_conf = {
86 	.efuse_size = 0x10,
87 	.rootkey_offset = 0,
88 };
89 
90 static const struct aw_sid_conf a64_conf = {
91 	.efuse_size = 0x100,
92 	.rootkey_offset = SID_SRAM,
93 	.has_prctl = true,
94 	.has_thermal = true,
95 };
96 
97 static const struct aw_sid_conf a83t_conf = {
98 	.efuse_size = 0x100,
99 	.rootkey_offset = SID_SRAM,
100 	.has_prctl = true,
101 	.has_thermal = true,
102 };
103 
104 static const struct aw_sid_conf h3_conf = {
105 	.efuse_size = 0x100,
106 	.rootkey_offset = SID_SRAM,
107 	.has_prctl = true,
108 	.has_thermal = true,
109 	.requires_prctl_read = true,
110 };
111 
112 static struct ofw_compat_data compat_data[] = {
113 	{ "allwinner,sun4i-a10-sid",		(uintptr_t)&a10_conf},
114 	{ "allwinner,sun7i-a20-sid",		(uintptr_t)&a20_conf},
115 	{ "allwinner,sun50i-a64-sid",		(uintptr_t)&a64_conf},
116 	{ "allwinner,sun8i-a83t-sid",		(uintptr_t)&a83t_conf},
117 	{ "allwinner,sun8i-h3-sid",		(uintptr_t)&h3_conf},
118 	{ NULL,					0 }
119 };
120 
121 struct aw_sid_softc {
122 	device_t		sid_dev;
123 	struct resource		*res;
124 	struct aw_sid_conf	*sid_conf;
125 	struct mtx		prctl_mtx;
126 };
127 
128 static struct aw_sid_softc *aw_sid_sc;
129 
130 static struct resource_spec aw_sid_spec[] = {
131 	{ SYS_RES_MEMORY,	0,	RF_ACTIVE },
132 	{ -1, 0 }
133 };
134 
135 enum sid_keys {
136 	AW_SID_ROOT_KEY,
137 };
138 
139 #define	RD4(sc, reg)		bus_read_4((sc)->res, (reg))
140 #define	WR4(sc, reg, val)	bus_write_4((sc)->res, (reg), (val))
141 
142 #define	PRCTL_RD4(sc, reg, val)	aw_sid_prctl_read((sc)->sid_dev, (reg), (val))
143 
144 static int aw_sid_sysctl(SYSCTL_HANDLER_ARGS);
145 static int aw_sid_prctl_read(device_t dev, bus_size_t offset, uint32_t *val);
146 
147 
148 /*
149  * offset here is offset into efuse space, rather than offset into sid register
150  * space. This form of read is only an option for newer SoC: A83t, H3, A64
151  */
152 static int
153 aw_sid_prctl_read(device_t dev, bus_size_t offset, uint32_t *val)
154 {
155 	struct aw_sid_softc *sc;
156 	uint32_t readval;
157 
158 	sc = device_get_softc(dev);
159 	if (!sc->sid_conf->has_prctl)
160 		return (1);
161 
162 	mtx_lock(&sc->prctl_mtx);
163 	readval = SID_PRCTL_OFFSET(offset) | SID_PRCTL_LOCK | SID_PRCTL_READ;
164 	WR4(sc, SID_PRCTL, readval);
165 	/* Read bit will be cleared once read has concluded */
166 	while (RD4(sc, SID_PRCTL) & SID_PRCTL_READ)
167 		continue;
168 	readval = RD4(sc, SID_RDKEY);
169 	mtx_unlock(&sc->prctl_mtx);
170 	*val = readval;
171 
172 	return (0);
173 }
174 
175 static int
176 aw_sid_probe(device_t dev)
177 {
178 	if (!ofw_bus_status_okay(dev))
179 		return (ENXIO);
180 
181 	if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0)
182 		return (ENXIO);
183 
184 	device_set_desc(dev, "Allwinner Secure ID Controller");
185 	return (BUS_PROBE_DEFAULT);
186 }
187 
188 static int
189 aw_sid_attach(device_t dev)
190 {
191 	struct aw_sid_softc *sc;
192 
193 	sc = device_get_softc(dev);
194 	sc->sid_dev = dev;
195 
196 	if (bus_alloc_resources(dev, aw_sid_spec, &sc->res) != 0) {
197 		device_printf(dev, "cannot allocate resources for device\n");
198 		return (ENXIO);
199 	}
200 
201 	mtx_init(&sc->prctl_mtx, device_get_nameunit(dev), NULL, MTX_DEF);
202 	sc->sid_conf = (struct aw_sid_conf *)ofw_bus_search_compatible(dev, compat_data)->ocd_data;
203 	aw_sid_sc = sc;
204 
205 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
206 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)),
207 	    OID_AUTO, "rootkey",
208 	    CTLTYPE_STRING | CTLFLAG_RD,
209 	    dev, AW_SID_ROOT_KEY, aw_sid_sysctl, "A", "Root Key");
210 
211 	return (0);
212 }
213 
214 int
215 aw_sid_read_tscalib(uint32_t *calib0, uint32_t *calib1)
216 {
217 	struct aw_sid_softc *sc;
218 
219 	sc = aw_sid_sc;
220 	if (sc == NULL)
221 		return (ENXIO);
222 	if (!sc->sid_conf->has_thermal)
223 		return (ENXIO);
224 
225 	if (sc->sid_conf->requires_prctl_read) {
226 		PRCTL_RD4(sc, SID_THERMAL_CALIB0_OFF, calib0);
227 		PRCTL_RD4(sc, SID_THERMAL_CALIB1_OFF, calib1);
228 	} else {
229 		*calib0 = RD4(sc, SID_THERMAL_CALIB0);
230 		*calib1 = RD4(sc, SID_THERMAL_CALIB1);
231 	}
232 
233 	return (0);
234 }
235 
236 int
237 aw_sid_get_rootkey(u_char *out)
238 {
239 	struct aw_sid_softc *sc;
240 	int i;
241 	bus_size_t root_key_off;
242 	u_int tmp;
243 
244 	sc = aw_sid_sc;
245 	if (sc == NULL)
246 		return (ENXIO);
247 	root_key_off = aw_sid_sc->sid_conf->rootkey_offset;
248 	for (i = 0; i < ROOT_KEY_SIZE ; i++) {
249 		if (sc->sid_conf->requires_prctl_read)
250 			PRCTL_RD4(sc, (i * 4), &tmp);
251 		else
252 			tmp = RD4(aw_sid_sc, root_key_off + (i * 4));
253 		be32enc(&out[i * 4], tmp);
254 	}
255 
256 	return (0);
257 }
258 
259 static int
260 aw_sid_sysctl(SYSCTL_HANDLER_ARGS)
261 {
262 	enum sid_keys key = arg2;
263 	u_char rootkey[16];
264 	char out[33];
265 
266 	if (key != AW_SID_ROOT_KEY)
267 		return (ENOENT);
268 
269 	if (aw_sid_get_rootkey(rootkey) != 0)
270 		return (ENOENT);
271 	snprintf(out, sizeof(out),
272 	  "%16D", rootkey, "");
273 
274 	return sysctl_handle_string(oidp, out, sizeof(out), req);
275 }
276 
277 static device_method_t aw_sid_methods[] = {
278 	/* Device interface */
279 	DEVMETHOD(device_probe,		aw_sid_probe),
280 	DEVMETHOD(device_attach,	aw_sid_attach),
281 
282 	DEVMETHOD_END
283 };
284 
285 static driver_t aw_sid_driver = {
286 	"aw_sid",
287 	aw_sid_methods,
288 	sizeof(struct aw_sid_softc),
289 };
290 
291 static devclass_t aw_sid_devclass;
292 
293 EARLY_DRIVER_MODULE(aw_sid, simplebus, aw_sid_driver, aw_sid_devclass, 0, 0,
294     BUS_PASS_RESOURCE + BUS_PASS_ORDER_FIRST);
295 MODULE_VERSION(aw_sid, 1);
296