bcm2835_bsc.c revision 1.1.4.2
1 /* $NetBSD: bcm2835_bsc.c,v 1.1.4.2 2013/02/13 01:36:14 riz Exp $ */ 2 3 /* 4 * Copyright (c) 2012 Jonathan A. Kollasch 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 COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 20 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 21 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 25 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 26 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: bcm2835_bsc.c,v 1.1.4.2 2013/02/13 01:36:14 riz Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/device.h> 34 #include <sys/systm.h> 35 #include <sys/mutex.h> 36 #include <sys/bus.h> 37 #include <sys/intr.h> 38 39 #include <dev/i2c/i2cvar.h> 40 41 #include <arm/broadcom/bcm_amba.h> 42 #include <arm/broadcom/bcm2835reg.h> 43 #include <arm/broadcom/bcm2835_bscreg.h> 44 #include <arm/broadcom/bcm2835_gpio_subr.h> 45 46 #if defined(_KERNEL_OPT) 47 #include "opt_kernhist.h" 48 #endif 49 #include <sys/kernhist.h> 50 51 KERNHIST_DECL(bsciichist); 52 53 struct bsciic_softc { 54 device_t sc_dev; 55 bus_space_tag_t sc_iot; 56 bus_space_handle_t sc_ioh; 57 bus_size_t sc_ios; 58 struct i2c_controller sc_i2c; 59 kmutex_t sc_buslock; 60 void *sc_inth; 61 }; 62 63 static int bsciic_match(device_t, cfdata_t, void *); 64 static void bsciic_attach(device_t, device_t, void *); 65 66 void bsciic_dump_regs(struct bsciic_softc * const); 67 68 static int bsciic_acquire_bus(void *, int); 69 static void bsciic_release_bus(void *, int); 70 static int bsciic_exec(void *, i2c_op_t, i2c_addr_t, const void *, size_t, 71 void *, size_t, int); 72 73 CFATTACH_DECL_NEW(bsciic, sizeof(struct bsciic_softc), 74 bsciic_match, bsciic_attach, NULL, NULL); 75 76 static int 77 bsciic_match(device_t parent, cfdata_t match, void *aux) 78 { 79 struct amba_attach_args * const aaa = aux; 80 81 if (strcmp(aaa->aaa_name, "bcmbsc") != 0) 82 return 0; 83 84 return 1; 85 } 86 87 static void 88 bsciic_attach(device_t parent, device_t self, void *aux) 89 { 90 struct bsciic_softc * const sc = device_private(self); 91 struct amba_attach_args * const aaa = aux; 92 struct i2cbus_attach_args iba; 93 u_int bscunit = ~0; 94 95 switch (aaa->aaa_addr) { 96 case BCM2835_BSC0_BASE: 97 bscunit = 0; 98 break; 99 case BCM2835_BSC1_BASE: 100 bscunit = 1; 101 break; 102 } 103 104 aprint_naive("\n"); 105 aprint_normal(": BSC%u\n", bscunit); 106 107 KERNHIST_INIT(bsciichist, 512); 108 109 sc->sc_dev = self; 110 111 mutex_init(&sc->sc_buslock, MUTEX_DEFAULT, IPL_NONE); 112 113 sc->sc_iot = aaa->aaa_iot; 114 if (bus_space_map(aaa->aaa_iot, aaa->aaa_addr, aaa->aaa_size, 0, 115 &sc->sc_ioh) != 0) { 116 aprint_error_dev(sc->sc_dev, "unable to map device\n"); 117 return; 118 } 119 sc->sc_ios = aaa->aaa_size; 120 121 switch (aaa->aaa_addr) { 122 case BCM2835_BSC0_BASE: 123 /* SDA0 on GPIO0, SCL0 on GPIO1 */ 124 bcm2835gpio_function_select(0, BCM2835_GPIO_ALT0); 125 bcm2835gpio_function_select(1, BCM2835_GPIO_ALT0); 126 break; 127 case BCM2835_BSC1_BASE: 128 /* SDA1 on GPIO2, SCL1 on GPIO3 */ 129 bcm2835gpio_function_select(2, BCM2835_GPIO_ALT0); 130 bcm2835gpio_function_select(3, BCM2835_GPIO_ALT0); 131 break; 132 } 133 134 /* clear FIFO, disable controller */ 135 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_C, BSC_C_CLEAR_CLEAR); 136 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_S, BSC_S_CLKT | 137 BSC_S_ERR | BSC_S_DONE); 138 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_DIV, 139 __SHIFTIN(250000000/100000, BSC_DIV_CDIV)); // XXX may not be this 140 141 sc->sc_i2c.ic_cookie = sc; 142 sc->sc_i2c.ic_acquire_bus = bsciic_acquire_bus; 143 sc->sc_i2c.ic_release_bus = bsciic_release_bus; 144 sc->sc_i2c.ic_exec = bsciic_exec; 145 146 memset(&iba, 0, sizeof(iba)); 147 148 iba.iba_tag = &sc->sc_i2c; 149 iba.iba_type = 0; 150 config_found_ia(self, "i2cbus", &iba, iicbus_print); 151 } 152 153 void 154 bsciic_dump_regs(struct bsciic_softc * const sc) 155 { 156 KERNHIST_FUNC(__func__); 157 KERNHIST_CALLED(bsciichist); 158 159 KERNHIST_LOG(bsciichist, "C %08x S %08x D %08x A %08x", 160 bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_C), 161 bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S), 162 bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_DLEN), 163 bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_A) 164 ); 165 } 166 167 static int 168 bsciic_acquire_bus(void *v, int flags) 169 { 170 struct bsciic_softc * const sc = v; 171 uint32_t s; 172 173 mutex_enter(&sc->sc_buslock); 174 175 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_S, BSC_S_CLKT | 176 BSC_S_ERR | BSC_S_DONE); 177 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_C, BSC_C_I2CEN | 178 BSC_C_CLEAR_CLEAR); 179 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 180 KASSERT((s & BSC_S_TA) == 0); 181 182 return 0; 183 } 184 185 static void 186 bsciic_release_bus(void *v, int flags) 187 { 188 struct bsciic_softc * const sc = v; 189 190 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_C, BSC_C_CLEAR_CLEAR); 191 192 mutex_exit(&sc->sc_buslock); 193 } 194 195 static int 196 bsciic_exec(void *v, i2c_op_t op, i2c_addr_t addr, const void *cmdbuf, 197 size_t cmdlen, void *databuf, size_t datalen, int flags) 198 { 199 KERNHIST_FUNC(__func__); KERNHIST_CALLED(bsciichist); 200 struct bsciic_softc * const sc = v; 201 uint32_t c, s, dlen, a; 202 uint32_t j; 203 uint8_t *buf; 204 size_t len; 205 size_t pos; 206 int error = 0; 207 const bool isread = I2C_OP_READ_P(op); 208 209 flags |= I2C_F_POLL; 210 211 #if 0 212 device_printf(sc->sc_dev, "exec: op %d, addr 0x%x, cmdbuf %p, " 213 "cmdlen %zu, databuf %p, datalen %zu, flags 0x%x\n", 214 op, addr, cmdbuf, cmdlen, databuf, datalen, flags); 215 #endif 216 217 a = __SHIFTIN(addr, BSC_A_ADDR); 218 c = BSC_C_I2CEN | BSC_C_CLEAR_CLEAR; 219 #if notyet 220 c |= BSC_C_INTR | BSC_C_INTT | BSC_C_INTD; 221 #endif 222 223 buf = __UNCONST(cmdbuf); 224 len = cmdlen; 225 226 if (isread) 227 dlen = cmdlen; 228 else 229 dlen = cmdlen + datalen; 230 dlen = __SHIFTIN(dlen, BSC_DLEN_DLEN); 231 232 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 233 if ((s & BSC_S_TA) != 0) 234 bsciic_dump_regs(sc); 235 KASSERT((s & BSC_S_TA) == 0); 236 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_DLEN, dlen); 237 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_A, a); 238 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_C, c | BSC_C_ST); 239 240 do { 241 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 242 } while ((s & BSC_S_TA) == 0); 243 244 flood_again: 245 KERNHIST_LOG(bsciichist, "flood top %p %zu", buf, len, 0, 0); 246 j = 10000000; 247 for (pos = 0; pos < len; ) { 248 if (--j == 0) 249 return -1; 250 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 251 KERNHIST_LOG(bsciichist, "w s %08x", s, 0, 0, 0); 252 if ((s & BSC_S_CLKT) != 0) { 253 error = EIO; 254 goto done; 255 } 256 if ((s & BSC_S_ERR) != 0) { 257 error = EIO; 258 goto done; 259 } 260 if ((s & BSC_S_DONE) != 0) 261 break; 262 if ((s & BSC_S_TXD) == 0) 263 continue; 264 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_FIFO, buf[pos]); 265 KERNHIST_LOG(bsciichist, "w %p %p %02x", buf, &buf[pos], 266 buf[pos], 0); 267 pos++; 268 } 269 KERNHIST_LOG(bsciichist, "flood bot %p %zu", buf, len, 0, 0); 270 271 if (buf == cmdbuf && !isread) { 272 buf = databuf; 273 len = datalen; 274 goto flood_again; 275 } 276 277 do { 278 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 279 } while ((s & BSC_S_TA) != 0); 280 281 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 282 s &= BSC_S_CLKT|BSC_S_ERR|BSC_S_DONE; 283 KASSERT((s & BSC_S_DONE) != 0); 284 if (s != 0) 285 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_S, s); 286 287 if (!isread) 288 goto done; 289 290 c |= BSC_C_READ; 291 292 buf = databuf; 293 len = datalen; 294 dlen = datalen; 295 296 dlen = __SHIFTIN(dlen, BSC_DLEN_DLEN); 297 KASSERT(dlen >= 1); 298 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_DLEN, dlen); 299 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_A, a); 300 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_C, c | BSC_C_ST); 301 302 do { 303 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 304 } while ((s & BSC_S_TA) == 0); 305 306 KERNHIST_LOG(bsciichist, "drain top %p %zu", buf, len, 0, 0); 307 j = 10000000; 308 for (pos = 0; pos < len; ) { 309 if (--j == 0) 310 return -1; 311 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 312 KERNHIST_LOG(bsciichist, "r s %08x", s, 0, 0, 0); 313 if ((s & BSC_S_CLKT) != 0) { 314 error = EIO; 315 goto done; 316 } 317 if ((s & BSC_S_ERR) != 0) { 318 error = EIO; 319 goto done; 320 } 321 if ((s & BSC_S_DONE) != 0) 322 break; 323 if ((s & BSC_S_RXD) == 0) 324 continue; 325 j = 10000000; 326 buf[pos] = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_FIFO); 327 KERNHIST_LOG(bsciichist, "r %p %p %02x", buf, &buf[pos], 328 buf[pos], 0); 329 pos++; 330 } 331 KERNHIST_LOG(bsciichist, "drain bot %p %zu", buf, len, 0, 0); 332 333 do { 334 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 335 } while ((s & BSC_S_TA) != 0); 336 337 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 338 s &= BSC_S_CLKT|BSC_S_ERR|BSC_S_DONE; 339 KASSERT((s & BSC_S_DONE) != 0); 340 if (s != 0) 341 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_S, s); 342 343 done: 344 bsciic_dump_regs(sc); 345 346 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_DLEN, 0); 347 348 do { 349 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 350 } while ((s & BSC_S_TA) != 0); 351 352 bsciic_dump_regs(sc); 353 354 s = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BSC_S); 355 s &= BSC_S_CLKT|BSC_S_ERR|BSC_S_DONE; 356 if (s != 0) 357 bus_space_write_4(sc->sc_iot, sc->sc_ioh, BSC_S, s); 358 359 bsciic_dump_regs(sc); 360 361 return error; 362 } 363
Indexes created Tue Oct 21 12:09:54 GMT 2025