1 /* $NetBSD: imxspi.c,v 1.15 2025/09/10 04:17:18 thorpej Exp $ */ 2 3 /*- 4 * Copyright (c) 2014 Genetec Corporation. All rights reserved. 5 * Written by Hashimoto Kenichi for Genetec Corporation. 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 GENETEC CORPORATION ``AS IS'' AND 17 * 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 GENETEC CORPORATION 20 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 * POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * this module support CSPI and eCSPI. 31 * i.MX51 have 2 eCSPI and 1 CSPI modules. 32 */ 33 34 #include <sys/cdefs.h> 35 __KERNEL_RCSID(0, "$NetBSD: imxspi.c,v 1.15 2025/09/10 04:17:18 thorpej Exp $"); 36 37 #include "opt_imxspi.h" 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/kernel.h> 42 #include <sys/device.h> 43 #include <sys/errno.h> 44 #include <sys/proc.h> 45 #include <sys/intr.h> 46 47 #include <sys/bus.h> 48 #include <machine/cpu.h> 49 #include <machine/intr.h> 50 51 #include <arm/imx/imxspivar.h> 52 #include <arm/imx/imxspireg.h> 53 54 /* SPI service routines */ 55 static int imxspi_configure_enhanced(void *, int, int, int); 56 static int imxspi_configure(void *, int, int, int); 57 static int imxspi_transfer(void *, struct spi_transfer *); 58 59 /* internal stuff */ 60 void imxspi_done(struct imxspi_softc *, int); 61 void imxspi_send(struct imxspi_softc *); 62 void imxspi_recv(struct imxspi_softc *); 63 void imxspi_sched(struct imxspi_softc *); 64 65 #define IMXCSPI_TYPE(type, x) \ 66 ((sc->sc_type == IMX31_CSPI) ? __CONCAT(CSPI_IMX31_, x) : \ 67 (sc->sc_type == IMX35_CSPI) ? __CONCAT(CSPI_IMX35_, x) : 0) 68 #define IMXCSPI(x) __CONCAT(CSPI_, x) 69 #define IMXESPI(x) __CONCAT(ECSPI_, x) 70 #define IMXSPI(x) ((sc->sc_enhanced) ? IMXESPI(x) : IMXCSPI(x)) 71 #define IMXSPI_TYPE(x) ((sc->sc_enhanced) ? IMXESPI(x) : IMXCSPI_TYPE(sc->sc_type, x)) 72 #define READ_REG(sc, x) \ 73 bus_space_read_4(sc->sc_iot, sc->sc_ioh, IMXSPI(x)) 74 #define WRITE_REG(sc, x, v) \ 75 bus_space_write_4(sc->sc_iot, sc->sc_ioh, IMXSPI(x), (v)) 76 77 #ifdef IMXSPI_DEBUG 78 int imxspi_debug = IMXSPI_DEBUG; 79 #define DPRINTFN(n,x) if (imxspi_debug>(n)) printf x; 80 #else 81 #define DPRINTFN(n,x) 82 #endif 83 84 int 85 imxspi_attach_common(device_t self) 86 { 87 struct imxspi_softc * const sc = device_private(self); 88 89 aprint_normal("i.MX %sCSPI Controller (clock %ld Hz)\n", 90 ((sc->sc_enhanced) ? "e" : ""), sc->sc_freq); 91 92 /* Initialize SPI controller */ 93 sc->sc_dev = self; 94 sc->sc_spi.sct_cookie = sc; 95 if (sc->sc_enhanced) 96 sc->sc_spi.sct_configure = imxspi_configure_enhanced; 97 else 98 sc->sc_spi.sct_configure = imxspi_configure; 99 sc->sc_spi.sct_transfer = imxspi_transfer; 100 101 /* sc->sc_spi.sct_nslaves must have been initialized by machdep code */ 102 sc->sc_spi.sct_nslaves = sc->sc_nslaves; 103 if (!sc->sc_spi.sct_nslaves) 104 aprint_error_dev(sc->sc_dev, "no slaves!\n"); 105 106 /* initialize the queue */ 107 SIMPLEQ_INIT(&sc->sc_q); 108 109 /* configure SPI */ 110 /* Setup Control Register */ 111 WRITE_REG(sc, CONREG, 112 __SHIFTIN(0, IMXSPI_TYPE(CON_DRCTL)) | 113 __SHIFTIN(8 - 1, IMXSPI_TYPE(CON_BITCOUNT)) | 114 __SHIFTIN(0xf, IMXSPI(CON_MODE)) | IMXSPI(CON_ENABLE)); 115 /* TC and RR interruption */ 116 WRITE_REG(sc, INTREG, (IMXSPI_TYPE(INTR_TC_EN) | IMXSPI(INTR_RR_EN))); 117 WRITE_REG(sc, STATREG, IMXSPI_TYPE(STAT_CLR)); 118 119 WRITE_REG(sc, PERIODREG, 0x0); 120 121 spibus_attach(self, &sc->sc_spi); 122 123 return 0; 124 } 125 126 static int 127 imxspi_configure(void *arg, int slave, int mode, int speed) 128 { 129 struct imxspi_softc *sc = arg; 130 uint32_t div_cnt = 0; 131 uint32_t div; 132 uint32_t contrl = 0; 133 134 div = (sc->sc_freq + (speed - 1)) / speed; 135 div = div - 1; 136 for (div_cnt = 0; div > 0; div_cnt++) 137 div >>= 1; 138 139 div_cnt = div_cnt - 2; 140 if (div_cnt >= 7) 141 div_cnt = 7; 142 143 contrl = READ_REG(sc, CONREG); 144 contrl &= ~CSPI_CON_DIV; 145 contrl |= __SHIFTIN(div_cnt, CSPI_CON_DIV); 146 147 contrl &= ~(CSPI_CON_POL | CSPI_CON_PHA); 148 switch (mode) { 149 case SPI_MODE_0: 150 /* CPHA = 0, CPOL = 0 */ 151 break; 152 case SPI_MODE_1: 153 /* CPHA = 1, CPOL = 0 */ 154 contrl |= CSPI_CON_PHA; 155 break; 156 case SPI_MODE_2: 157 /* CPHA = 0, CPOL = 1 */ 158 contrl |= CSPI_CON_POL; 159 break; 160 case SPI_MODE_3: 161 /* CPHA = 1, CPOL = 1 */ 162 contrl |= CSPI_CON_POL; 163 contrl |= CSPI_CON_PHA; 164 break; 165 default: 166 return EINVAL; 167 } 168 WRITE_REG(sc, CONREG, contrl); 169 170 DPRINTFN(3, ("%s: slave %d mode %d speed %d\n", 171 __func__, slave, mode, speed)); 172 173 return 0; 174 } 175 176 static int 177 imxspi_configure_enhanced(void *arg, int slave, int mode, int speed) 178 { 179 struct imxspi_softc *sc = arg; 180 uint32_t div_cnt = 0; 181 uint32_t div; 182 uint32_t contrl = 0; 183 uint32_t config = 0; 184 185 div = (sc->sc_freq + (speed - 1)) / speed; 186 for (div_cnt = 0; div > 0; div_cnt++) 187 div >>= 1; 188 189 if (div_cnt >= 15) 190 div_cnt = 15; 191 192 contrl = READ_REG(sc, CONREG); 193 contrl |= __SHIFTIN(div_cnt, ECSPI_CON_DIV); 194 contrl |= __SHIFTIN(slave, ECSPI_CON_CS); 195 contrl |= __SHIFTIN(__BIT(slave), ECSPI_CON_MODE); 196 WRITE_REG(sc, CONREG, contrl); 197 198 config = bus_space_read_4(sc->sc_iot, sc->sc_ioh, ECSPI_CONFIGREG); 199 config &= ~(__SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_POL) | 200 __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_CTL) | 201 __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_PHA)); 202 switch (mode) { 203 case SPI_MODE_0: 204 /* CPHA = 0, CPOL = 0 */ 205 break; 206 case SPI_MODE_1: 207 /* CPHA = 1, CPOL = 0 */ 208 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_PHA); 209 break; 210 case SPI_MODE_2: 211 /* CPHA = 0, CPOL = 1 */ 212 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_POL); 213 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_CTL); 214 break; 215 case SPI_MODE_3: 216 /* CPHA = 1, CPOL = 1 */ 217 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_PHA); 218 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_POL); 219 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SCLK_CTL); 220 break; 221 default: 222 return EINVAL; 223 } 224 config |= __SHIFTIN(__BIT(slave), ECSPI_CONFIG_SSB_CTL); 225 bus_space_write_4(sc->sc_iot, sc->sc_ioh, ECSPI_CONFIGREG, config); 226 227 DPRINTFN(3, ("%s: slave %d mode %d speed %d\n", 228 __func__, slave, mode, speed)); 229 230 return 0; 231 } 232 233 void 234 imxspi_send(struct imxspi_softc *sc) 235 { 236 uint32_t data; 237 struct spi_chunk *chunk; 238 239 /* fill the fifo */ 240 while ((chunk = sc->sc_wchunk) != NULL) { 241 while (chunk->chunk_wresid) { 242 /* transmit fifo full? */ 243 if (READ_REG(sc, STATREG) & IMXSPI(STAT_TF)) 244 goto out; 245 246 if (chunk->chunk_wptr) { 247 data = *chunk->chunk_wptr; 248 chunk->chunk_wptr++; 249 } else { 250 data = 0xff; 251 } 252 chunk->chunk_wresid--; 253 254 WRITE_REG(sc, TXDATA, data); 255 } 256 /* advance to next transfer */ 257 sc->sc_wchunk = sc->sc_wchunk->chunk_next; 258 } 259 out: 260 if (!(READ_REG(sc, STATREG) & IMXSPI(INTR_TE_EN))) 261 WRITE_REG(sc, CONREG, READ_REG(sc, CONREG) | IMXSPI(CON_XCH)); 262 } 263 264 void 265 imxspi_recv(struct imxspi_softc *sc) 266 { 267 uint32_t data; 268 struct spi_chunk *chunk; 269 270 while ((chunk = sc->sc_rchunk) != NULL) { 271 while (chunk->chunk_rresid) { 272 /* rx fifo empty? */ 273 if ((!(READ_REG(sc, STATREG) & IMXSPI(STAT_RR)))) 274 return; 275 276 /* collect rx data */ 277 data = READ_REG(sc, RXDATA); 278 if (chunk->chunk_rptr) { 279 *chunk->chunk_rptr = data & 0xff; 280 chunk->chunk_rptr++; 281 } 282 283 chunk->chunk_rresid--; 284 } 285 /* advance next to next transfer */ 286 sc->sc_rchunk = sc->sc_rchunk->chunk_next; 287 } 288 } 289 290 291 void 292 imxspi_sched(struct imxspi_softc *sc) 293 { 294 struct spi_transfer *st; 295 uint32_t chipselect; 296 297 while ((st = spi_transq_first(&sc->sc_q)) != NULL) { 298 /* remove the item */ 299 spi_transq_dequeue(&sc->sc_q); 300 301 /* note that we are working on it */ 302 sc->sc_transfer = st; 303 304 /* chip select */ 305 if (sc->sc_tag->spi_cs_enable != NULL) 306 sc->sc_tag->spi_cs_enable(sc->sc_tag->cookie, 307 st->st_slave); 308 309 /* chip select */ 310 chipselect = READ_REG(sc, CONREG); 311 chipselect &= ~IMXSPI_TYPE(CON_CS); 312 chipselect |= __SHIFTIN(st->st_slave, IMXSPI_TYPE(CON_CS)); 313 WRITE_REG(sc, CONREG, chipselect); 314 315 delay(1); 316 317 /* setup chunks */ 318 sc->sc_rchunk = sc->sc_wchunk = st->st_chunks; 319 320 /* now kick the master start to get the chip running */ 321 imxspi_send(sc); 322 323 sc->sc_running = TRUE; 324 return; 325 } 326 327 DPRINTFN(2, ("%s: nothing to do anymore\n", __func__)); 328 sc->sc_running = FALSE; 329 } 330 331 void 332 imxspi_done(struct imxspi_softc *sc, int err) 333 { 334 struct spi_transfer *st; 335 336 /* called from interrupt handler */ 337 if ((st = sc->sc_transfer) != NULL) { 338 if (sc->sc_tag->spi_cs_disable != NULL) 339 sc->sc_tag->spi_cs_disable(sc->sc_tag->cookie, 340 st->st_slave); 341 342 sc->sc_transfer = NULL; 343 spi_done(st, err); 344 } 345 /* make sure we clear these bits out */ 346 sc->sc_wchunk = sc->sc_rchunk = NULL; 347 imxspi_sched(sc); 348 } 349 350 int 351 imxspi_intr(void *arg) 352 { 353 struct imxspi_softc *sc = arg; 354 uint32_t intr, sr; 355 int err = 0; 356 357 if ((intr = READ_REG(sc, INTREG)) == 0) { 358 /* interrupts are not enabled, get out */ 359 DPRINTFN(4, ("%s: interrupts are not enabled\n", __func__)); 360 return 0; 361 } 362 363 sr = READ_REG(sc, STATREG); 364 if (!(sr & intr)) { 365 /* interrupt did not happen, get out */ 366 DPRINTFN(3, ("%s: interrupts did not happen\n", __func__)); 367 return 0; 368 } 369 370 /* RXFIFO ready? */ 371 if (sr & IMXSPI(INTR_RR_EN)) { 372 imxspi_recv(sc); 373 if (sc->sc_wchunk == NULL && sc->sc_rchunk == NULL) 374 imxspi_done(sc, err); 375 } 376 377 /* Transfer Complete? */ 378 if (sr & IMXSPI_TYPE(INTR_TC_EN)) 379 imxspi_send(sc); 380 381 /* status register clear */ 382 WRITE_REG(sc, STATREG, sr); 383 384 return 1; 385 } 386 387 int 388 imxspi_transfer(void *arg, struct spi_transfer *st) 389 { 390 struct imxspi_softc *sc = arg; 391 int s; 392 393 /* make sure we select the right chip */ 394 s = splbio(); 395 spi_transq_enqueue(&sc->sc_q, st); 396 if (sc->sc_running == FALSE) 397 imxspi_sched(sc); 398 splx(s); 399 400 return 0; 401 } 402 403