jh7110_trng.c revision 1.1
1 /* $NetBSD: jh7110_trng.c,v 1.1 2025/02/08 16:12:20 skrll Exp $ */ 2 3 /*- 4 * Copyright (c) 2025 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Nick Hudson 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: jh7110_trng.c,v 1.1 2025/02/08 16:12:20 skrll Exp $"); 34 35 #include <sys/param.h> 36 37 #include <sys/bus.h> 38 #include <sys/device.h> 39 #include <sys/condvar.h> 40 #include <sys/mutex.h> 41 #include <sys/rndsource.h> 42 43 #include <dev/fdt/fdtvar.h> 44 45 46 struct jh7110_trng_softc { 47 device_t sc_dev; 48 bus_space_tag_t sc_bst; 49 bus_space_handle_t sc_bsh; 50 int sc_phandle; 51 52 kmutex_t sc_lock; 53 kcondvar_t sc_cv; 54 void * sc_ih; 55 bool sc_reseeddone; 56 size_t sc_bytes_wanted; 57 58 krndsource_t sc_rndsource; 59 }; 60 61 62 #define RD4(sc, reg) \ 63 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 64 #define WR4(sc, reg, val) \ 65 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 66 67 68 /* Register definitions */ 69 // https://doc-en.rvspace.org/JH7110/TRM/JH7110_TRM/control_registers_trng.html?hl=trng 70 #define JH7110_TRNG_CTRL 0x0000 71 #define JH7110_TRNG_CTRL_NOP 0x0 72 #define JH7110_TRNG_CTRL_RANDOMIZE 0x1 73 #define JH7110_TRNG_CTRL_RANDOM_RESEED 0x2 74 #define JH7110_TRNG_CTRL_NONCE_RESEED 0x3 75 #define JH7110_TRNG_STAT 0x0004 76 #define JH7110_TRNG_STAT_SEEDED __BIT(9) 77 78 //XXXNH check 79 #define JH7110_TRNG_MODE 0x0008 80 #define JH7110_TRNG_MODE_R256 __BIT(3) 81 #define JH7110_TRNG_SMODE 0x000c 82 #define JH7110_TRNG_IENABLE 0x0010 83 #define JH7110_TRNG_IENABLE_GLOBAL __BIT(31) 84 #define JH7110_TRNG_IENABLE_LFSR_LOCKUP __BIT(4) 85 #define JH7110_TRNG_IENABLE_RQST_LOCKUP __BIT(3) 86 #define JH7110_TRNG_IENABLE_AGE_ALARM __BIT(2) 87 #define JH7110_TRNG_IENABLE_SEED_DONE __BIT(1) 88 #define JH7110_TRNG_IENABLE_RAND_RDY __BIT(0) 89 #define JH7110_TRNG_ISTATUS 0x0014 90 #define JH7110_TRNG_ISTATUS_LFSR_LOCKUP __BIT(4) 91 #define JH7110_TRNG_ISTATUS_RQST_LOCKUP __BIT(3) 92 #define JH7110_TRNG_ISTATUS_AGE_ALARM __BIT(2) 93 #define JH7110_TRNG_ISTATUS_SEED_DONE __BIT(1) 94 #define JH7110_TRNG_ISTATUS_RAND_RDY __BIT(0) 95 #define JH7110_TRNG_DATA0 0x0020 96 #define JH7110_TRNG_DATA1 0x0024 97 #define JH7110_TRNG_DATA2 0x0028 98 #define JH7110_TRNG_DATA3 0x002c 99 #define JH7110_TRNG_DATA4 0x0030 100 #define JH7110_TRNG_DATA5 0x0034 101 #define JH7110_TRNG_DATA6 0x0038 102 #define JH7110_TRNG_DATA7 0x003c 103 104 105 #define RD4(sc, reg) \ 106 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 107 #define WR4(sc, reg, val) \ 108 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 109 110 111 static void 112 jh7110_trng_irqenable(struct jh7110_trng_softc *sc) 113 { 114 WR4(sc, JH7110_TRNG_IENABLE, 115 JH7110_TRNG_IENABLE_GLOBAL | 116 JH7110_TRNG_IENABLE_SEED_DONE | 117 JH7110_TRNG_IENABLE_RAND_RDY | 118 JH7110_TRNG_IENABLE_LFSR_LOCKUP); 119 } 120 121 static void 122 jh7110_trng_irqdisable(struct jh7110_trng_softc *sc) 123 { 124 WR4(sc, JH7110_TRNG_IENABLE, 0); 125 } 126 127 static void 128 jh7110_trng_probe(struct jh7110_trng_softc *sc, uint32_t istat) 129 { 130 KASSERT(mutex_owned(&sc->sc_lock)); 131 132 if (sc->sc_bytes_wanted != 0) { 133 uint32_t data[8]; 134 const uint32_t stat = RD4(sc, JH7110_TRNG_STAT); 135 136 if (stat & JH7110_TRNG_STAT_SEEDED) { 137 if (istat & JH7110_TRNG_ISTATUS_RAND_RDY) { 138 139 WR4(sc, JH7110_TRNG_ISTATUS, 140 JH7110_TRNG_ISTATUS_RAND_RDY); 141 142 data[0] = RD4(sc, JH7110_TRNG_DATA0); 143 data[1] = RD4(sc, JH7110_TRNG_DATA1); 144 data[2] = RD4(sc, JH7110_TRNG_DATA2); 145 data[3] = RD4(sc, JH7110_TRNG_DATA3); 146 data[4] = RD4(sc, JH7110_TRNG_DATA4); 147 data[5] = RD4(sc, JH7110_TRNG_DATA5); 148 data[6] = RD4(sc, JH7110_TRNG_DATA6); 149 data[7] = RD4(sc, JH7110_TRNG_DATA7); 150 151 rnd_add_data_sync(&sc->sc_rndsource, &data, 152 sizeof(data), sizeof(data) * NBBY); 153 154 sc->sc_bytes_wanted -= 155 MIN(sc->sc_bytes_wanted, sizeof(data)); 156 157 if (sc->sc_bytes_wanted == 0) 158 jh7110_trng_irqdisable(sc); 159 } 160 } else { 161 WR4(sc, JH7110_TRNG_CTRL, 162 JH7110_TRNG_CTRL_RANDOM_RESEED); 163 } 164 explicit_memset(data, 0, sizeof data); 165 } 166 if (sc->sc_bytes_wanted != 0) { 167 WR4(sc, JH7110_TRNG_CTRL, 168 JH7110_TRNG_CTRL_RANDOMIZE); 169 } 170 } 171 172 static void 173 jh7110_trng_get(size_t bytes_wanted, void *arg) 174 { 175 struct jh7110_trng_softc * const sc = arg; 176 177 mutex_enter(&sc->sc_lock); 178 sc->sc_bytes_wanted += bytes_wanted; 179 180 jh7110_trng_irqenable(sc); 181 182 const uint32_t istat = RD4(sc, JH7110_TRNG_ISTATUS); 183 jh7110_trng_probe(sc, istat); 184 185 mutex_exit(&sc->sc_lock); 186 } 187 188 189 static int 190 jh7110_trng_intr(void *priv) 191 { 192 struct jh7110_trng_softc * const sc = priv; 193 194 mutex_enter(&sc->sc_lock); 195 196 const uint32_t istat = RD4(sc, JH7110_TRNG_ISTATUS); 197 198 if (istat & JH7110_TRNG_ISTATUS_RAND_RDY) { 199 KASSERT(RD4(sc, JH7110_TRNG_STAT) & JH7110_TRNG_STAT_SEEDED); 200 jh7110_trng_probe(sc, istat); 201 //sc->sc_randready = true; 202 203 } 204 205 if (istat & JH7110_TRNG_ISTATUS_SEED_DONE) 206 sc->sc_reseeddone = true; 207 208 #if 0 209 if (istat & JH7110_TRNG_ISTATUS_LFSR_LOCKUP) { 210 sc->sc_reseeddone = false; 211 } 212 #endif 213 WR4(sc, JH7110_TRNG_ISTATUS, istat); 214 215 if (sc->sc_reseeddone) 216 cv_broadcast(&sc->sc_cv); 217 218 mutex_exit(&sc->sc_lock); 219 220 return 1; 221 } 222 223 224 static void 225 jh7110_trng_init(struct jh7110_trng_softc *sc) 226 { 227 /* Mask and clear all interrupts. */ 228 WR4(sc, JH7110_TRNG_IENABLE, 0U); 229 WR4(sc, JH7110_TRNG_ISTATUS, ~0U); 230 231 WR4(sc, JH7110_TRNG_MODE, JH7110_TRNG_MODE_R256); 232 233 mutex_enter(&sc->sc_lock); 234 235 jh7110_trng_irqenable(sc); 236 237 sc->sc_reseeddone = false; 238 WR4(sc, JH7110_TRNG_CTRL, JH7110_TRNG_CTRL_RANDOM_RESEED); 239 240 while (!sc->sc_reseeddone) { 241 const int error = cv_timedwait(&sc->sc_cv, &sc->sc_lock, 1); 242 if (error) { 243 printf("%s: timedout\n", __func__); 244 mutex_exit(&sc->sc_lock); 245 return; 246 } 247 } 248 mutex_exit(&sc->sc_lock); 249 } 250 251 static void 252 jh7110_trng_attach_i(device_t self) 253 { 254 struct jh7110_trng_softc * const sc = device_private(self); 255 256 jh7110_trng_init(sc); 257 258 /* set up an rndsource */ 259 rndsource_setcb(&sc->sc_rndsource, &jh7110_trng_get, sc); 260 rnd_attach_source(&sc->sc_rndsource, device_xname(self), RND_TYPE_RNG, 261 RND_FLAG_COLLECT_VALUE | RND_FLAG_HASCB); 262 } 263 264 /* Compat string(s) */ 265 static const struct device_compatible_entry compat_data[] = { 266 { .compat = "starfive,jh7110-trng" }, 267 DEVICE_COMPAT_EOL 268 }; 269 270 271 static int 272 jh7110_trng_match(device_t parent, cfdata_t cf, void *aux) 273 { 274 struct fdt_attach_args * const faa = aux; 275 276 return of_compatible_match(faa->faa_phandle, compat_data); 277 } 278 279 static void 280 jh7110_trng_attach(device_t parent, device_t self, void *aux) 281 { 282 struct jh7110_trng_softc * const sc = device_private(self); 283 struct fdt_attach_args * const faa = aux; 284 const int phandle = faa->faa_phandle; 285 bus_space_tag_t bst = faa->faa_bst; 286 bus_addr_t addr; 287 bus_size_t size; 288 int error; 289 290 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) { 291 aprint_error(": couldn't get registers\n"); 292 return; 293 } 294 295 error = bus_space_map(bst, addr, size, 0, &sc->sc_bsh); 296 if (error) { 297 aprint_error(": couldn't map %#" PRIxBUSADDR ": %d", addr, 298 error); 299 return; 300 } 301 302 /* Enable the hclk clock. */ 303 error = fdtbus_clock_enable(phandle, "hclk", true); 304 if (error) { 305 aprint_error(": couldn't enable 'hclk' clock\n"); 306 return; 307 } 308 309 /* Enable the hclk clock. */ 310 error = fdtbus_clock_enable(phandle, "ahb", true); 311 if (error) { 312 aprint_error(": couldn't enable 'ahb' clock\n"); 313 return; 314 } 315 316 /* Get a reset handle if we need and try to deassert it. */ 317 struct fdtbus_reset * const rst = fdtbus_reset_get_index(phandle, 0); 318 if (rst != NULL) { 319 if (fdtbus_reset_deassert(rst) != 0) { 320 aprint_error(": couldn't de-assert reset\n"); 321 return; 322 } 323 } 324 325 sc->sc_dev = self; 326 sc->sc_phandle = phandle; 327 sc->sc_bst = bst; 328 329 mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_VM); 330 cv_init(&sc->sc_cv, "jh7110trng"); 331 332 aprint_naive("\n"); 333 aprint_normal(": JH7110 TRNG\n"); 334 335 char intrstr[128]; 336 if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) { 337 aprint_error_dev(self, "failed to decode interrupt\n"); 338 return; 339 } 340 341 sc->sc_ih = fdtbus_intr_establish_xname(phandle, 0, IPL_VM, 342 FDT_INTR_MPSAFE, jh7110_trng_intr, sc, device_xname(self)); 343 if (sc->sc_ih == NULL) { 344 aprint_error_dev(self, "failed to establish interrupt on %s\n", 345 intrstr); 346 return; 347 } 348 aprint_normal_dev(self, "interrupting on %s\n", intrstr); 349 350 config_interrupts(self, jh7110_trng_attach_i); 351 } 352 353 CFATTACH_DECL_NEW(jh7110_trng, sizeof(struct jh7110_trng_softc), 354 jh7110_trng_match, jh7110_trng_attach, NULL, NULL); 355
Indexes created Tue Sep 30 20:09:53 GMT 2025