sunxi_rsb.c revision 1.16
1 /* $NetBSD: sunxi_rsb.c,v 1.16 2025/09/16 11:55:17 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2014-2017 Jared McNeill <jmcneill (at) invisible.ca> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 22 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: sunxi_rsb.c,v 1.16 2025/09/16 11:55:17 thorpej Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/bus.h> 34 #include <sys/device.h> 35 #include <sys/intr.h> 36 #include <sys/systm.h> 37 #include <sys/kernel.h> 38 #include <sys/mutex.h> 39 #include <sys/condvar.h> 40 41 #include <dev/i2c/i2cvar.h> 42 43 #include <dev/fdt/fdtvar.h> 44 45 #include <arm/sunxi/sunxi_rsb.h> 46 47 enum sunxi_rsb_type { 48 SUNXI_P2WI, 49 SUNXI_RSB, 50 }; 51 52 static const struct device_compatible_entry compat_data[] = { 53 { .compat = "allwinner,sun6i-a31-p2wi", .value = SUNXI_P2WI }, 54 { .compat = "allwinner,sun8i-a23-rsb", .value = SUNXI_RSB }, 55 DEVICE_COMPAT_EOL 56 }; 57 58 #define RSB_ADDR_PMIC_PRIMARY 0x3a3 59 #define RSB_ADDR_PMIC_SECONDARY 0x745 60 #define RSB_ADDR_PERIPH_IC 0xe89 61 62 /* 63 * Device address to Run-time address mappings. 64 * 65 * Run-time address (RTA) is an 8-bit value used to address the device during 66 * a read or write transaction. The following are valid RTAs: 67 * 0x17 0x2d 0x3a 0x4e 0x59 0x63 0x74 0x8b 0x9c 0xa6 0xb1 0xc5 0xd2 0xe8 0xff 68 * 69 * Allwinner uses RTA 0x2d for the primary PMIC, 0x3a for the secondary PMIC, 70 * and 0x4e for the peripheral IC (where applicable). 71 */ 72 static const struct { 73 uint16_t addr; 74 uint8_t rta; 75 } rsb_rtamap[] = { 76 { .addr = RSB_ADDR_PMIC_PRIMARY, .rta = 0x2d }, 77 { .addr = RSB_ADDR_PMIC_SECONDARY, .rta = 0x3a }, 78 { .addr = RSB_ADDR_PERIPH_IC, .rta = 0x4e }, 79 { .addr = 0, .rta = 0 } 80 }; 81 82 struct sunxi_rsb_softc { 83 device_t sc_dev; 84 bus_space_tag_t sc_bst; 85 bus_space_handle_t sc_bsh; 86 enum sunxi_rsb_type sc_type; 87 struct i2c_controller sc_ic; 88 kmutex_t sc_intr_lock; 89 kcondvar_t sc_intr_wait; 90 device_t sc_i2cdev; 91 void *sc_ih; 92 uint32_t sc_stat; 93 bool sc_busy; 94 95 uint16_t sc_rsb_last_da; 96 }; 97 98 #define RSB_READ(sc, reg) \ 99 bus_space_read_4((sc)->sc_bst, (sc)->sc_bsh, (reg)) 100 #define RSB_WRITE(sc, reg, val) \ 101 bus_space_write_4((sc)->sc_bst, (sc)->sc_bsh, (reg), (val)) 102 103 static int sunxi_rsb_exec(void *, i2c_op_t, i2c_addr_t, const void *, 104 size_t, void *, size_t, int); 105 106 static int sunxi_rsb_intr(void *); 107 static int sunxi_rsb_wait(struct sunxi_rsb_softc *, int); 108 static int sunxi_rsb_rsb_config(struct sunxi_rsb_softc *, 109 uint8_t, i2c_addr_t, int); 110 111 static int sunxi_rsb_match(device_t, cfdata_t, void *); 112 static void sunxi_rsb_attach(device_t, device_t, void *); 113 114 CFATTACH_DECL_NEW(sunxi_rsb, sizeof(struct sunxi_rsb_softc), 115 sunxi_rsb_match, sunxi_rsb_attach, NULL, NULL); 116 117 static int 118 sunxi_rsb_match(device_t parent, cfdata_t cf, void *aux) 119 { 120 struct fdt_attach_args * const faa = aux; 121 122 return of_compatible_match(faa->faa_phandle, compat_data); 123 } 124 125 static void 126 sunxi_rsb_attach(device_t parent, device_t self, void *aux) 127 { 128 struct sunxi_rsb_softc * const sc = device_private(self); 129 struct fdt_attach_args * const faa = aux; 130 const int phandle = faa->faa_phandle; 131 struct fdtbus_reset *rst; 132 struct clk *clk; 133 char intrstr[128]; 134 bus_addr_t addr; 135 bus_size_t size; 136 137 if (fdtbus_get_reg(phandle, 0, &addr, &size) != 0) { 138 aprint_error(": couldn't get registers\n"); 139 return; 140 } 141 142 if (!fdtbus_intr_str(phandle, 0, intrstr, sizeof(intrstr))) { 143 aprint_error(": couldn't decode interrupt\n"); 144 return; 145 } 146 147 if ((clk = fdtbus_clock_get_index(phandle, 0)) != NULL) 148 if (clk_enable(clk) != 0) { 149 aprint_error(": couldn't enable clock\n"); 150 return; 151 } 152 if ((rst = fdtbus_reset_get_index(phandle, 0)) != NULL) 153 if (fdtbus_reset_deassert(rst) != 0) { 154 aprint_error(": couldn't de-assert reset\n"); 155 return; 156 } 157 158 sc->sc_dev = self; 159 sc->sc_type = of_compatible_lookup(phandle, compat_data)->value; 160 sc->sc_bst = faa->faa_bst; 161 if (bus_space_map(sc->sc_bst, addr, size, 0, &sc->sc_bsh) != 0) { 162 aprint_error(": couldn't map registers\n"); 163 return; 164 } 165 166 mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_SCHED); 167 cv_init(&sc->sc_intr_wait, "sunxirsb"); 168 169 aprint_naive("\n"); 170 aprint_normal(": %s\n", sc->sc_type == SUNXI_P2WI ? "P2WI" : "RSB"); 171 172 sc->sc_ih = fdtbus_intr_establish_xname(phandle, 0, IPL_VM, 0, 173 sunxi_rsb_intr, sc, device_xname(self)); 174 if (sc->sc_ih == NULL) { 175 aprint_error_dev(self, "couldn't establish interrupt on %s\n", 176 intrstr); 177 return; 178 } 179 aprint_normal_dev(self, "interrupting on %s\n", intrstr); 180 181 iic_tag_init(&sc->sc_ic); 182 sc->sc_ic.ic_cookie = sc; 183 sc->sc_ic.ic_exec = sunxi_rsb_exec; 184 185 iicbus_attach(self, &sc->sc_ic); 186 } 187 188 static int 189 sunxi_rsb_intr(void *priv) 190 { 191 struct sunxi_rsb_softc *sc = priv; 192 uint32_t stat; 193 194 stat = RSB_READ(sc, RSB_STAT_REG); 195 if ((stat & RSB_STAT_MASK) == 0) 196 return 0; 197 198 RSB_WRITE(sc, RSB_STAT_REG, stat & RSB_STAT_MASK); 199 200 mutex_enter(&sc->sc_intr_lock); 201 sc->sc_stat |= stat; 202 cv_broadcast(&sc->sc_intr_wait); 203 mutex_exit(&sc->sc_intr_lock); 204 205 return 1; 206 } 207 208 static int 209 sunxi_rsb_soft_reset(struct sunxi_rsb_softc *sc) 210 { 211 int retry = 1000; 212 213 RSB_WRITE(sc, RSB_CTRL_REG, RSB_CTRL_SOFT_RESET); 214 while (--retry > 0) { 215 if ((RSB_READ(sc, RSB_CTRL_REG) & RSB_CTRL_SOFT_RESET) == 0) 216 break; 217 delay(10); 218 } 219 if (retry == 0) 220 return EIO; 221 222 return 0; 223 } 224 225 static int 226 sunxi_rsb_wait(struct sunxi_rsb_softc *sc, int flags) 227 { 228 int error = 0, retry; 229 230 /* Wait up to 5 seconds for a transfer to complete */ 231 sc->sc_stat = 0; 232 for (retry = (flags & I2C_F_POLL) ? 100 : 5; retry > 0; retry--) { 233 if (flags & I2C_F_POLL) { 234 sc->sc_stat |= RSB_READ(sc, RSB_STAT_REG); 235 } else { 236 error = cv_timedwait(&sc->sc_intr_wait, 237 &sc->sc_intr_lock, hz); 238 if (error && error != EWOULDBLOCK) { 239 break; 240 } 241 } 242 if (sc->sc_stat & RSB_STAT_MASK) { 243 break; 244 } 245 if (flags & I2C_F_POLL) { 246 delay(10000); 247 } 248 } 249 if (retry == 0) 250 error = EAGAIN; 251 252 if (flags & I2C_F_POLL) { 253 RSB_WRITE(sc, RSB_STAT_REG, 254 sc->sc_stat & RSB_STAT_MASK); 255 } 256 257 if (error) { 258 /* Abort transaction */ 259 device_printf(sc->sc_dev, "transfer timeout, error = %d\n", 260 error); 261 RSB_WRITE(sc, RSB_CTRL_REG, 262 RSB_CTRL_ABORT_TRANS); 263 return error; 264 } 265 266 if (sc->sc_stat & RSB_STAT_LOAD_BSY) { 267 device_printf(sc->sc_dev, "transfer busy\n"); 268 return EBUSY; 269 } 270 if (sc->sc_stat & RSB_STAT_TRANS_ERR) { 271 device_printf(sc->sc_dev, "transfer error, id 0x%02" PRIx64 272 "\n", __SHIFTOUT(sc->sc_stat, RSB_STAT_TRANS_ERR_ID)); 273 return EIO; 274 } 275 276 return 0; 277 } 278 279 static int 280 sunxi_rsb_rsb_config(struct sunxi_rsb_softc *sc, uint8_t rta, i2c_addr_t da, 281 int flags) 282 { 283 uint32_t dar, ctrl; 284 285 KASSERT(mutex_owned(&sc->sc_intr_lock)); 286 287 RSB_WRITE(sc, RSB_STAT_REG, 288 RSB_READ(sc, RSB_STAT_REG) & RSB_STAT_MASK); 289 290 dar = __SHIFTIN(rta, RSB_DAR_RTA); 291 dar |= __SHIFTIN(da, RSB_DAR_DA); 292 RSB_WRITE(sc, RSB_DAR_REG, dar); 293 RSB_WRITE(sc, RSB_CMD_REG, RSB_CMD_IDX_SRTA); 294 295 /* Make sure the controller is idle */ 296 ctrl = RSB_READ(sc, RSB_CTRL_REG); 297 if (ctrl & RSB_CTRL_START_TRANS) { 298 device_printf(sc->sc_dev, "device is busy\n"); 299 return EBUSY; 300 } 301 302 /* Start the transfer */ 303 RSB_WRITE(sc, RSB_CTRL_REG, 304 ctrl | RSB_CTRL_START_TRANS); 305 306 return sunxi_rsb_wait(sc, flags); 307 } 308 309 static int 310 sunxi_rsb_exec(void *priv, i2c_op_t op, i2c_addr_t addr, 311 const void *cmdbuf, size_t cmdlen, void *buf, size_t len, int flags) 312 { 313 struct sunxi_rsb_softc *sc = priv; 314 uint32_t dlen, ctrl; 315 uint8_t rta; 316 int error, i; 317 318 if (cmdlen != 1 || (len != 1 && len != 2 && len != 4)) 319 return EINVAL; 320 321 mutex_enter(&sc->sc_intr_lock); 322 323 error = sunxi_rsb_soft_reset(sc); 324 if (error != 0) { 325 mutex_exit(&sc->sc_intr_lock); 326 device_printf(sc->sc_dev, "soft reset timed out\n"); 327 return error; 328 } 329 330 if ((flags & I2C_F_POLL) == 0) { 331 /* Enable interrupts */ 332 RSB_WRITE(sc, RSB_INTE_REG, 333 RSB_INTE_LOAD_BSY_ENB | 334 RSB_INTE_TRANS_ERR_ENB | 335 RSB_INTE_TRANS_OVER_ENB); 336 RSB_WRITE(sc, RSB_CTRL_REG, 337 RSB_CTRL_GLOBAL_INT_ENB); 338 } 339 340 if (sc->sc_type == SUNXI_RSB && sc->sc_rsb_last_da != addr) { 341 /* Lookup run-time address for given device address */ 342 for (rta = 0, i = 0; rsb_rtamap[i].rta != 0; i++) 343 if (rsb_rtamap[i].addr == addr) { 344 rta = rsb_rtamap[i].rta; 345 break; 346 } 347 if (rta == 0) { 348 mutex_exit(&sc->sc_intr_lock); 349 device_printf(sc->sc_dev, 350 "RTA not known for address %#x\n", addr); 351 return ENXIO; 352 } 353 error = sunxi_rsb_rsb_config(sc, rta, addr, flags); 354 if (error) { 355 device_printf(sc->sc_dev, 356 "SRTA failed, flags = %x, error = %d\n", 357 flags, error); 358 sc->sc_rsb_last_da = 0; 359 goto done; 360 } 361 362 sc->sc_rsb_last_da = addr; 363 } 364 365 /* Data byte register */ 366 RSB_WRITE(sc, RSB_DADDR0_REG, *(const uint8_t *)cmdbuf); 367 368 if (I2C_OP_WRITE_P(op)) { 369 uint8_t *pbuf = buf; 370 uint32_t data; 371 /* Write data */ 372 switch (len) { 373 case 1: 374 data = pbuf[0]; 375 break; 376 case 2: 377 data = pbuf[0] | (pbuf[1] << 8); 378 break; 379 case 4: 380 data = pbuf[0] | (pbuf[1] << 8) | 381 (pbuf[2] << 16) | (pbuf[3] << 24); 382 break; 383 default: 384 error = EINVAL; 385 goto done; 386 } 387 RSB_WRITE(sc, RSB_DATA0_REG, data); 388 } 389 390 if (sc->sc_type == SUNXI_RSB) { 391 uint8_t cmd; 392 if (I2C_OP_WRITE_P(op)) { 393 switch (len) { 394 case 1: cmd = RSB_CMD_IDX_WR8; break; 395 case 2: cmd = RSB_CMD_IDX_WR16; break; 396 case 4: cmd = RSB_CMD_IDX_WR32; break; 397 default: error = EINVAL; goto done; 398 } 399 } else { 400 switch (len) { 401 case 1: cmd = RSB_CMD_IDX_RD8; break; 402 case 2: cmd = RSB_CMD_IDX_RD16; break; 403 case 4: cmd = RSB_CMD_IDX_RD32; break; 404 default: error = EINVAL; goto done; 405 } 406 } 407 RSB_WRITE(sc, RSB_CMD_REG, cmd); 408 } 409 410 /* Program data length register; if reading, set read/write bit */ 411 dlen = __SHIFTIN(len - 1, RSB_DLEN_ACCESS_LENGTH); 412 if (I2C_OP_READ_P(op)) { 413 dlen |= RSB_DLEN_READ_WRITE_FLAG; 414 } 415 RSB_WRITE(sc, RSB_DLEN_REG, dlen); 416 417 /* Make sure the controller is idle */ 418 ctrl = RSB_READ(sc, RSB_CTRL_REG); 419 if (ctrl & RSB_CTRL_START_TRANS) { 420 device_printf(sc->sc_dev, "device is busy\n"); 421 error = EBUSY; 422 goto done; 423 } 424 425 /* Start the transfer */ 426 RSB_WRITE(sc, RSB_CTRL_REG, 427 ctrl | RSB_CTRL_START_TRANS); 428 429 error = sunxi_rsb_wait(sc, flags); 430 if (error) 431 goto done; 432 433 if (I2C_OP_READ_P(op)) { 434 uint32_t data = RSB_READ(sc, RSB_DATA0_REG); 435 switch (len) { 436 case 4: 437 *(uint32_t *)buf = data; 438 break; 439 case 2: 440 *(uint16_t *)buf = data & 0xffff; 441 break; 442 case 1: 443 *(uint8_t *)buf = data & 0xff; 444 break; 445 default: 446 error = EINVAL; 447 goto done; 448 } 449 } 450 451 error = 0; 452 453 done: 454 RSB_WRITE(sc, RSB_CTRL_REG, 0); 455 mutex_exit(&sc->sc_intr_lock); 456 457 return error; 458 } 459
Indexes created Fri Oct 03 02:09:57 GMT 2025