1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2019 Axiado Corporation 5 * All rights reserved. 6 * 7 * This software was developed in part by Philip Paeps and Kristof Provost 8 * under contract for Axiado Corporation. 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 AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/bus.h> 35 #include <sys/kernel.h> 36 #include <sys/lock.h> 37 #include <sys/module.h> 38 #include <sys/mutex.h> 39 #include <sys/rman.h> 40 41 #include <machine/bus.h> 42 #include <machine/cpu.h> 43 44 #include <dev/clk/clk.h> 45 46 #include <dev/ofw/ofw_bus.h> 47 #include <dev/ofw/ofw_bus_subr.h> 48 #include <dev/ofw/openfirm.h> 49 50 #include <dev/spibus/spi.h> 51 #include <dev/spibus/spibusvar.h> 52 53 #include "spibus_if.h" 54 55 #if 1 56 #define DBGPRINT(dev, fmt, args...) \ 57 device_printf(dev, "%s: " fmt "\n", __func__, ## args) 58 #else 59 #define DBGPRINT(dev, fmt, args...) 60 #endif 61 62 static struct resource_spec sfspi_spec[] = { 63 { SYS_RES_MEMORY, 0, RF_ACTIVE }, 64 RESOURCE_SPEC_END 65 }; 66 67 struct sfspi_softc { 68 device_t dev; 69 device_t parent; 70 71 struct mtx mtx; 72 73 struct resource *res; 74 bus_space_tag_t bst; 75 bus_space_handle_t bsh; 76 77 void *ih; 78 79 clk_t clk; 80 uint64_t freq; 81 uint32_t cs_max; 82 }; 83 84 #define SFSPI_LOCK(sc) mtx_lock(&(sc)->mtx) 85 #define SFSPI_UNLOCK(sc) mtx_unlock(&(sc)->mtx) 86 #define SFSPI_ASSERT_LOCKED(sc) mtx_assert(&(sc)->mtx, MA_OWNED); 87 #define SFSPI_ASSERT_UNLOCKED(sc) mtx_assert(&(sc)->mtx, MA_NOTOWNED); 88 89 /* 90 * Register offsets. 91 * From Sifive-Unleashed-FU540-C000-v1.0.pdf page 101. 92 */ 93 #define SFSPI_REG_SCKDIV 0x00 /* Serial clock divisor */ 94 #define SFSPI_REG_SCKMODE 0x04 /* Serial clock mode */ 95 #define SFSPI_REG_CSID 0x10 /* Chip select ID */ 96 #define SFSPI_REG_CSDEF 0x14 /* Chip select default */ 97 #define SFSPI_REG_CSMODE 0x18 /* Chip select mode */ 98 #define SFSPI_REG_DELAY0 0x28 /* Delay control 0 */ 99 #define SFSPI_REG_DELAY1 0x2C /* Delay control 1 */ 100 #define SFSPI_REG_FMT 0x40 /* Frame format */ 101 #define SFSPI_REG_TXDATA 0x48 /* Tx FIFO data */ 102 #define SFSPI_REG_RXDATA 0x4C /* Rx FIFO data */ 103 #define SFSPI_REG_TXMARK 0x50 /* Tx FIFO watermark */ 104 #define SFSPI_REG_RXMARK 0x54 /* Rx FIFO watermark */ 105 #define SFSPI_REG_FCTRL 0x60 /* SPI flash interface control* */ 106 #define SFSPI_REG_FFMT 0x64 /* SPI flash instruction format* */ 107 #define SFSPI_REG_IE 0x70 /* SPI interrupt enable */ 108 #define SFSPI_REG_IP 0x74 /* SPI interrupt pending */ 109 110 #define SFSPI_SCKDIV_MASK 0xfff 111 112 #define SFSPI_CSDEF_ALL ((1 << sc->cs_max)-1) 113 114 #define SFSPI_CSMODE_AUTO 0x0U 115 #define SFSPI_CSMODE_HOLD 0x2U 116 #define SFSPI_CSMODE_OFF 0x3U 117 118 #define SFSPI_TXDATA_DATA_MASK 0xff 119 #define SFSPI_TXDATA_FULL (1 << 31) 120 121 #define SFSPI_RXDATA_DATA_MASK 0xff 122 #define SFSPI_RXDATA_EMPTY (1 << 31) 123 124 #define SFSPI_SCKMODE_PHA (1 << 0) 125 #define SFSPI_SCKMODE_POL (1 << 1) 126 127 #define SFSPI_FMT_PROTO_SINGLE 0x0U 128 #define SFSPI_FMT_PROTO_DUAL 0x1U 129 #define SFSPI_FMT_PROTO_QUAD 0x2U 130 #define SFSPI_FMT_PROTO_MASK 0x3U 131 #define SFSPI_FMT_ENDIAN (1 << 2) 132 #define SFSPI_FMT_DIR (1 << 3) 133 #define SFSPI_FMT_LEN(x) ((uint32_t)(x) << 16) 134 #define SFSPI_FMT_LEN_MASK (0xfU << 16) 135 136 #define SFSPI_FIFO_DEPTH 8 137 138 #define SFSPI_READ(_sc, _reg) \ 139 bus_space_read_4((_sc)->bst, (_sc)->bsh, (_reg)) 140 #define SFSPI_WRITE(_sc, _reg, _val) \ 141 bus_space_write_4((_sc)->bst, (_sc)->bsh, (_reg), (_val)) 142 143 static void 144 sfspi_tx(struct sfspi_softc *sc, uint8_t *buf, uint32_t bufsiz) 145 { 146 uint32_t val; 147 uint8_t *p, *end; 148 149 KASSERT(buf != NULL, ("TX buffer cannot be NULL")); 150 151 end = buf + bufsiz; 152 for (p = buf; p < end; p++) { 153 do { 154 val = SFSPI_READ(sc, SFSPI_REG_TXDATA); 155 } while (val & SFSPI_TXDATA_FULL); 156 val = *p; 157 SFSPI_WRITE(sc, SFSPI_REG_TXDATA, val); 158 } 159 } 160 161 static void 162 sfspi_rx(struct sfspi_softc *sc, uint8_t *buf, uint32_t bufsiz) 163 { 164 uint32_t val; 165 uint8_t *p, *end; 166 167 KASSERT(buf != NULL, ("RX buffer cannot be NULL")); 168 KASSERT(bufsiz <= SFSPI_FIFO_DEPTH, 169 ("Cannot receive more than %d bytes at a time\n", 170 SFSPI_FIFO_DEPTH)); 171 172 end = buf + bufsiz; 173 for (p = buf; p < end; p++) { 174 do { 175 val = SFSPI_READ(sc, SFSPI_REG_RXDATA); 176 } while (val & SFSPI_RXDATA_EMPTY); 177 *p = val & SFSPI_RXDATA_DATA_MASK; 178 }; 179 } 180 181 static int 182 sfspi_xfer_buf(struct sfspi_softc *sc, uint8_t *rxbuf, uint8_t *txbuf, 183 uint32_t txlen, uint32_t rxlen) 184 { 185 uint32_t bytes; 186 187 KASSERT(txlen == rxlen, ("TX and RX lengths must be equal")); 188 KASSERT(rxbuf != NULL, ("RX buffer cannot be NULL")); 189 KASSERT(txbuf != NULL, ("TX buffer cannot be NULL")); 190 191 while (txlen) { 192 bytes = (txlen > SFSPI_FIFO_DEPTH) ? SFSPI_FIFO_DEPTH : txlen; 193 sfspi_tx(sc, txbuf, bytes); 194 txbuf += bytes; 195 sfspi_rx(sc, rxbuf, bytes); 196 rxbuf += bytes; 197 txlen -= bytes; 198 } 199 200 return (0); 201 } 202 203 static int 204 sfspi_setup(struct sfspi_softc *sc, uint32_t cs, uint32_t mode, 205 uint32_t freq) 206 { 207 uint32_t csmode, fmt, sckdiv, sckmode; 208 209 SFSPI_ASSERT_LOCKED(sc); 210 211 /* 212 * Fsck = Fin / 2 * (div + 1) 213 * -> div = Fin / (2 * Fsck) - 1 214 */ 215 sckdiv = (howmany(sc->freq >> 1, freq) - 1) & SFSPI_SCKDIV_MASK; 216 SFSPI_WRITE(sc, SFSPI_REG_SCKDIV, sckdiv); 217 218 switch (mode) { 219 case SPIBUS_MODE_NONE: 220 sckmode = 0; 221 break; 222 case SPIBUS_MODE_CPHA: 223 sckmode = SFSPI_SCKMODE_PHA; 224 break; 225 case SPIBUS_MODE_CPOL: 226 sckmode = SFSPI_SCKMODE_POL; 227 break; 228 case SPIBUS_MODE_CPOL_CPHA: 229 sckmode = SFSPI_SCKMODE_PHA | SFSPI_SCKMODE_POL; 230 break; 231 default: 232 return (EINVAL); 233 } 234 SFSPI_WRITE(sc, SFSPI_REG_SCKMODE, sckmode); 235 236 csmode = SFSPI_CSMODE_HOLD; 237 if (cs & SPIBUS_CS_HIGH) 238 csmode = SFSPI_CSMODE_AUTO; 239 SFSPI_WRITE(sc, SFSPI_REG_CSMODE, csmode); 240 241 SFSPI_WRITE(sc, SFSPI_REG_CSID, cs & ~SPIBUS_CS_HIGH); 242 243 fmt = SFSPI_FMT_PROTO_SINGLE | SFSPI_FMT_LEN(8); 244 SFSPI_WRITE(sc, SFSPI_REG_FMT, fmt); 245 246 return (0); 247 } 248 249 static int 250 sfspi_transfer(device_t dev, device_t child, struct spi_command *cmd) 251 { 252 struct sfspi_softc *sc; 253 uint32_t clock, cs, csdef, mode; 254 int err; 255 256 KASSERT(cmd->tx_cmd_sz == cmd->rx_cmd_sz, 257 ("TX and RX command sizes must be equal")); 258 KASSERT(cmd->tx_data_sz == cmd->rx_data_sz, 259 ("TX and RX data sizes must be equal")); 260 261 sc = device_get_softc(dev); 262 spibus_get_cs(child, &cs); 263 spibus_get_clock(child, &clock); 264 spibus_get_mode(child, &mode); 265 266 if (cs > sc->cs_max) { 267 device_printf(sc->dev, "Invalid chip select %u\n", cs); 268 return (EINVAL); 269 } 270 271 SFSPI_LOCK(sc); 272 device_busy(sc->dev); 273 274 err = sfspi_setup(sc, cs, mode, clock); 275 if (err != 0) { 276 SFSPI_UNLOCK(sc); 277 return (err); 278 } 279 280 err = 0; 281 if (cmd->tx_cmd_sz > 0) 282 err = sfspi_xfer_buf(sc, cmd->rx_cmd, cmd->tx_cmd, 283 cmd->tx_cmd_sz, cmd->rx_cmd_sz); 284 if (cmd->tx_data_sz > 0 && err == 0) 285 err = sfspi_xfer_buf(sc, cmd->rx_data, cmd->tx_data, 286 cmd->tx_data_sz, cmd->rx_data_sz); 287 288 /* Deassert chip select. */ 289 csdef = SFSPI_CSDEF_ALL & ~(1 << cs); 290 SFSPI_WRITE(sc, SFSPI_REG_CSDEF, csdef); 291 SFSPI_WRITE(sc, SFSPI_REG_CSDEF, SFSPI_CSDEF_ALL); 292 293 device_unbusy(sc->dev); 294 SFSPI_UNLOCK(sc); 295 296 return (err); 297 } 298 299 static int 300 sfspi_attach(device_t dev) 301 { 302 struct sfspi_softc *sc; 303 int error; 304 305 sc = device_get_softc(dev); 306 sc->dev = dev; 307 308 mtx_init(&sc->mtx, device_get_nameunit(sc->dev), NULL, MTX_DEF); 309 310 error = bus_alloc_resources(dev, sfspi_spec, &sc->res); 311 if (error) { 312 device_printf(dev, "Couldn't allocate resources\n"); 313 goto fail; 314 } 315 sc->bst = rman_get_bustag(sc->res); 316 sc->bsh = rman_get_bushandle(sc->res); 317 318 error = clk_get_by_ofw_index(dev, 0, 0, &sc->clk); 319 if (error) { 320 device_printf(dev, "Couldn't allocate clock: %d\n", error); 321 goto fail; 322 } 323 error = clk_enable(sc->clk); 324 if (error) { 325 device_printf(dev, "Couldn't enable clock: %d\n", error); 326 goto fail; 327 } 328 329 error = clk_get_freq(sc->clk, &sc->freq); 330 if (error) { 331 device_printf(sc->dev, "Couldn't get frequency: %d\n", error); 332 goto fail; 333 } 334 335 /* 336 * From Sifive-Unleashed-FU540-C000-v1.0.pdf page 103: 337 * csdef is cs_width bits wide and all ones on reset. 338 */ 339 sc->cs_max = SFSPI_READ(sc, SFSPI_REG_CSDEF); 340 341 /* 342 * We don't support the direct-mapped flash interface. 343 * Disable it. 344 */ 345 SFSPI_WRITE(sc, SFSPI_REG_FCTRL, 0x0); 346 347 /* Probe and attach the spibus when interrupts are available. */ 348 sc->parent = device_add_child(dev, "spibus", DEVICE_UNIT_ANY); 349 bus_delayed_attach_children(dev); 350 351 return (0); 352 353 fail: 354 bus_release_resources(dev, sfspi_spec, &sc->res); 355 mtx_destroy(&sc->mtx); 356 return (error); 357 } 358 359 static int 360 sfspi_probe(device_t dev) 361 { 362 363 if (!ofw_bus_status_okay(dev)) 364 return (ENXIO); 365 366 if (!ofw_bus_is_compatible(dev, "sifive,spi0")) 367 return (ENXIO); 368 369 device_set_desc(dev, "SiFive SPI controller"); 370 371 return (BUS_PROBE_DEFAULT); 372 } 373 374 static phandle_t 375 sfspi_get_node(device_t bus, device_t dev) 376 { 377 378 return (ofw_bus_get_node(bus)); 379 } 380 381 static device_method_t sfspi_methods[] = { 382 DEVMETHOD(device_probe, sfspi_probe), 383 DEVMETHOD(device_attach, sfspi_attach), 384 385 DEVMETHOD(spibus_transfer, sfspi_transfer), 386 387 DEVMETHOD(ofw_bus_get_node, sfspi_get_node), 388 389 DEVMETHOD_END 390 }; 391 392 static driver_t sfspi_driver = { 393 "sifive_spi", 394 sfspi_methods, 395 sizeof(struct sfspi_softc) 396 }; 397 398 DRIVER_MODULE(sifive_spi, simplebus, sfspi_driver, 0, 0); 399 DRIVER_MODULE(ofw_spibus, sifive_spi, ofw_spibus_driver, 0, 0); 400 MODULE_DEPEND(sifive_spi, ofw_spibus, 1, 1, 1); 401