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 #define SID_THERMAL_CALIB0 (SID_SRAM + 0x34) 65 #define SID_THERMAL_CALIB1 (SID_SRAM + 0x38) 66 67 #define ROOT_KEY_SIZE 4 68 69 struct aw_sid_conf { 70 bus_size_t efuse_size; 71 bus_size_t rootkey_offset; 72 bool has_prctl; 73 bool has_thermal; 74 bool requires_prctl_read; 75 }; 76 77 static const struct aw_sid_conf a10_conf = { 78 .efuse_size = 0x10, 79 .rootkey_offset = 0, 80 }; 81 82 static const struct aw_sid_conf a20_conf = { 83 .efuse_size = 0x10, 84 .rootkey_offset = 0, 85 }; 86 87 static const struct aw_sid_conf a64_conf = { 88 .efuse_size = 0x100, 89 .rootkey_offset = SID_SRAM, 90 .has_prctl = true, 91 .has_thermal = true, 92 }; 93 94 static const struct aw_sid_conf a83t_conf = { 95 .efuse_size = 0x100, 96 .rootkey_offset = SID_SRAM, 97 .has_prctl = true, 98 .has_thermal = true, 99 }; 100 101 static const struct aw_sid_conf h3_conf = { 102 .efuse_size = 0x100, 103 .rootkey_offset = SID_SRAM, 104 .has_prctl = true, 105 .has_thermal = true, 106 .requires_prctl_read = true, 107 }; 108 109 static struct ofw_compat_data compat_data[] = { 110 { "allwinner,sun4i-a10-sid", (uintptr_t)&a10_conf}, 111 { "allwinner,sun7i-a20-sid", (uintptr_t)&a20_conf}, 112 { "allwinner,sun50i-a64-sid", (uintptr_t)&a64_conf}, 113 { "allwinner,sun8i-a83t-sid", (uintptr_t)&a83t_conf}, 114 { "allwinner,sun8i-h3-sid", (uintptr_t)&h3_conf}, 115 { NULL, 0 } 116 }; 117 118 struct aw_sid_softc { 119 struct resource *res; 120 struct aw_sid_conf *sid_conf; 121 struct mtx prctl_mtx; 122 }; 123 124 static struct aw_sid_softc *aw_sid_sc; 125 126 static struct resource_spec aw_sid_spec[] = { 127 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 128 { -1, 0 } 129 }; 130 131 enum sid_keys { 132 AW_SID_ROOT_KEY, 133 }; 134 135 #define RD4(sc, reg) bus_read_4((sc)->res, (reg)) 136 #define WR4(sc, reg, val) bus_write_4((sc)->res, (reg), (val)) 137 138 static int aw_sid_sysctl(SYSCTL_HANDLER_ARGS); 139 static int aw_sid_prctl_read(device_t dev, bus_size_t offset, uint32_t *val); 140 141 142 /* 143 * offset here is offset into efuse space, rather than offset into sid register 144 * space. This form of read is only an option for newer SoC: A83t, H3, A64 145 */ 146 static int 147 aw_sid_prctl_read(device_t dev, bus_size_t offset, uint32_t *val) 148 { 149 struct aw_sid_softc *sc; 150 uint32_t readval; 151 152 sc = device_get_softc(dev); 153 if (!sc->sid_conf->has_prctl) 154 return (1); 155 156 mtx_lock(&sc->prctl_mtx); 157 readval = SID_PRCTL_OFFSET(offset) | SID_PRCTL_LOCK | SID_PRCTL_READ; 158 WR4(sc, SID_PRCTL, readval); 159 /* Read bit will be cleared once read has concluded */ 160 while (RD4(sc, SID_PRCTL) & SID_PRCTL_READ) 161 continue; 162 readval = RD4(sc, SID_RDKEY); 163 mtx_unlock(&sc->prctl_mtx); 164 *val = readval; 165 166 return (0); 167 } 168 169 static int 170 aw_sid_probe(device_t dev) 171 { 172 if (!ofw_bus_status_okay(dev)) 173 return (ENXIO); 174 175 if (ofw_bus_search_compatible(dev, compat_data)->ocd_data == 0) 176 return (ENXIO); 177 178 device_set_desc(dev, "Allwinner Secure ID Controller"); 179 return (BUS_PROBE_DEFAULT); 180 } 181 182 static int 183 aw_sid_attach(device_t dev) 184 { 185 struct aw_sid_softc *sc; 186 bus_size_t i; 187 uint32_t val; 188 189 sc = device_get_softc(dev); 190 191 if (bus_alloc_resources(dev, aw_sid_spec, &sc->res) != 0) { 192 device_printf(dev, "cannot allocate resources for device\n"); 193 return (ENXIO); 194 } 195 196 mtx_init(&sc->prctl_mtx, device_get_nameunit(dev), NULL, MTX_DEF); 197 sc->sid_conf = (struct aw_sid_conf *)ofw_bus_search_compatible(dev, compat_data)->ocd_data; 198 aw_sid_sc = sc; 199 200 /* 201 * This set of reads is solely for working around a silicon bug on some 202 * SoC that require a prctl read in order for direct register access to 203 * return a non-garbled value. Hence, the values we read are simply 204 * ignored. 205 */ 206 if (sc->sid_conf->requires_prctl_read) 207 for (i = 0; i < sc->sid_conf->efuse_size; i += 4) 208 if (aw_sid_prctl_read(dev, i, &val) != 0) { 209 device_printf(dev, "failed prctl read\n"); 210 return (ENXIO); 211 } 212 213 SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev), 214 SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), 215 OID_AUTO, "rootkey", 216 CTLTYPE_STRING | CTLFLAG_RD, 217 dev, AW_SID_ROOT_KEY, aw_sid_sysctl, "A", "Root Key"); 218 219 return (0); 220 } 221 222 int 223 aw_sid_read_tscalib(uint32_t *calib0, uint32_t *calib1) 224 { 225 struct aw_sid_softc *sc; 226 227 sc = aw_sid_sc; 228 if (sc == NULL) 229 return (ENXIO); 230 if (!sc->sid_conf->has_thermal) 231 return (ENXIO); 232 233 *calib0 = RD4(sc, SID_THERMAL_CALIB0); 234 *calib1 = RD4(sc, SID_THERMAL_CALIB1); 235 236 return (0); 237 } 238 239 int 240 aw_sid_get_rootkey(u_char *out) 241 { 242 struct aw_sid_softc *sc; 243 int i; 244 bus_size_t root_key_off; 245 u_int tmp; 246 247 sc = aw_sid_sc; 248 if (sc == NULL) 249 return (ENXIO); 250 root_key_off = aw_sid_sc->sid_conf->rootkey_offset; 251 for (i = 0; i < ROOT_KEY_SIZE ; i++) { 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