drivers/spi/stm32_qspi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * (C) Copyright 2016
   4  *
   5  * Michael Kurz, <michi.kurz@gmail.com>
   6  *
   7  * STM32 QSPI driver
   8  */
   9
  10 #include <common.h>
  11 #include <clk.h>
  12 #include <reset.h>
  13 #include <spi-mem.h>
  14 #include <linux/iopoll.h>
  15 #include <linux/ioport.h>
  16 #include <linux/sizes.h>
  17
  18 struct stm32_qspi_regs {
  19         u32 cr;         /* 0x00 */
  20         u32 dcr;        /* 0x04 */
  21         u32 sr;         /* 0x08 */
  22         u32 fcr;        /* 0x0C */
  23         u32 dlr;        /* 0x10 */
  24         u32 ccr;        /* 0x14 */
  25         u32 ar;         /* 0x18 */
  26         u32 abr;        /* 0x1C */
  27         u32 dr;         /* 0x20 */
  28         u32 psmkr;      /* 0x24 */
  29         u32 psmar;      /* 0x28 */
  30         u32 pir;        /* 0x2C */
  31         u32 lptr;       /* 0x30 */
  32 };
  33
  34 /*
  35  * QUADSPI control register
  36  */
  37 #define STM32_QSPI_CR_EN                BIT(0)
  38 #define STM32_QSPI_CR_ABORT             BIT(1)
  39 #define STM32_QSPI_CR_DMAEN             BIT(2)
  40 #define STM32_QSPI_CR_TCEN              BIT(3)
  41 #define STM32_QSPI_CR_SSHIFT            BIT(4)
  42 #define STM32_QSPI_CR_DFM               BIT(6)
  43 #define STM32_QSPI_CR_FSEL              BIT(7)
  44 #define STM32_QSPI_CR_FTHRES_SHIFT      8
  45 #define STM32_QSPI_CR_TEIE              BIT(16)
  46 #define STM32_QSPI_CR_TCIE              BIT(17)
  47 #define STM32_QSPI_CR_FTIE              BIT(18)
  48 #define STM32_QSPI_CR_SMIE              BIT(19)
  49 #define STM32_QSPI_CR_TOIE              BIT(20)
  50 #define STM32_QSPI_CR_APMS              BIT(22)
  51 #define STM32_QSPI_CR_PMM               BIT(23)
  52 #define STM32_QSPI_CR_PRESCALER_MASK    GENMASK(7, 0)
  53 #define STM32_QSPI_CR_PRESCALER_SHIFT   24
  54
  55 /*
  56  * QUADSPI device configuration register
  57  */
  58 #define STM32_QSPI_DCR_CKMODE           BIT(0)
  59 #define STM32_QSPI_DCR_CSHT_MASK        GENMASK(2, 0)
  60 #define STM32_QSPI_DCR_CSHT_SHIFT       8
  61 #define STM32_QSPI_DCR_FSIZE_MASK       GENMASK(4, 0)
  62 #define STM32_QSPI_DCR_FSIZE_SHIFT      16
  63
  64 /*
  65  * QUADSPI status register
  66  */
  67 #define STM32_QSPI_SR_TEF               BIT(0)
  68 #define STM32_QSPI_SR_TCF               BIT(1)
  69 #define STM32_QSPI_SR_FTF               BIT(2)
  70 #define STM32_QSPI_SR_SMF               BIT(3)
  71 #define STM32_QSPI_SR_TOF               BIT(4)
  72 #define STM32_QSPI_SR_BUSY              BIT(5)
  73
  74 /*
  75  * QUADSPI flag clear register
  76  */
  77 #define STM32_QSPI_FCR_CTEF             BIT(0)
  78 #define STM32_QSPI_FCR_CTCF             BIT(1)
  79 #define STM32_QSPI_FCR_CSMF             BIT(3)
  80 #define STM32_QSPI_FCR_CTOF             BIT(4)
  81
  82 /*
  83  * QUADSPI communication configuration register
  84  */
  85 #define STM32_QSPI_CCR_DDRM             BIT(31)
  86 #define STM32_QSPI_CCR_DHHC             BIT(30)
  87 #define STM32_QSPI_CCR_SIOO             BIT(28)
  88 #define STM32_QSPI_CCR_FMODE_SHIFT      26
  89 #define STM32_QSPI_CCR_DMODE_SHIFT      24
  90 #define STM32_QSPI_CCR_DCYC_SHIFT       18
  91 #define STM32_QSPI_CCR_ABSIZE_SHIFT     16
  92 #define STM32_QSPI_CCR_ABMODE_SHIFT     14
  93 #define STM32_QSPI_CCR_ADSIZE_SHIFT     12
  94 #define STM32_QSPI_CCR_ADMODE_SHIFT     10
  95 #define STM32_QSPI_CCR_IMODE_SHIFT      8
  96
  97 #define STM32_QSPI_CCR_IND_WRITE        0
  98 #define STM32_QSPI_CCR_IND_READ         1
  99 #define STM32_QSPI_CCR_MEM_MAP          3
 100
 101 #define STM32_QSPI_MAX_MMAP_SZ          SZ_256M
 102 #define STM32_QSPI_MAX_CHIP             2
 103
 104 #define STM32_QSPI_FIFO_TIMEOUT_US      30000
 105 #define STM32_QSPI_CMD_TIMEOUT_US       1000000
 106 #define STM32_BUSY_TIMEOUT_US           100000
 107 #define STM32_ABT_TIMEOUT_US            100000
 108
 109 struct stm32_qspi_flash {
 110         u32 cr;
 111         u32 dcr;
 112         bool initialized;
 113 };
 114
 115 struct stm32_qspi_priv {
 116         struct stm32_qspi_regs *regs;
 117         struct stm32_qspi_flash flash[STM32_QSPI_MAX_CHIP];
 118         void __iomem *mm_base;
 119         resource_size_t mm_size;
 120         ulong clock_rate;
 121         int cs_used;
 122 };
 123
 124 static int _stm32_qspi_wait_for_not_busy(struct stm32_qspi_priv *priv)
 125 {
 126         u32 sr;
 127         int ret;
 128
 129         ret = readl_poll_timeout(&priv->regs->sr, sr,
 130                                  !(sr & STM32_QSPI_SR_BUSY),
 131                                  STM32_BUSY_TIMEOUT_US);
 132         if (ret)
 133                 pr_err("busy timeout (stat:%#x)\n", sr);
 134
 135         return ret;
 136 }
 137
 138 static int _stm32_qspi_wait_cmd(struct stm32_qspi_priv *priv,
 139                                 const struct spi_mem_op *op)
 140 {
 141         u32 sr;
 142         int ret;
 143
 144         if (!op->data.nbytes)
 145                 return _stm32_qspi_wait_for_not_busy(priv);
 146
 147         ret = readl_poll_timeout(&priv->regs->sr, sr,
 148                                  sr & STM32_QSPI_SR_TCF,
 149                                  STM32_QSPI_CMD_TIMEOUT_US);
 150         if (ret) {
 151                 pr_err("cmd timeout (stat:%#x)\n", sr);
 152         } else if (readl(&priv->regs->sr) & STM32_QSPI_SR_TEF) {
 153                 pr_err("transfer error (stat:%#x)\n", sr);
 154                 ret = -EIO;
 155         }
 156
 157         /* clear flags */
 158         writel(STM32_QSPI_FCR_CTCF | STM32_QSPI_FCR_CTEF, &priv->regs->fcr);
 159
 160         return ret;
 161 }
 162
 163 static void _stm32_qspi_read_fifo(u8 *val, void __iomem *addr)
 164 {
 165         *val = readb(addr);
 166 }
 167
 168 static void _stm32_qspi_write_fifo(u8 *val, void __iomem *addr)
 169 {
 170         writeb(*val, addr);
 171 }
 172
 173 static int _stm32_qspi_poll(struct stm32_qspi_priv *priv,
 174                             const struct spi_mem_op *op)
 175 {
 176         void (*fifo)(u8 *val, void __iomem *addr);
 177         u32 len = op->data.nbytes, sr;
 178         u8 *buf;
 179         int ret;
 180
 181         if (op->data.dir == SPI_MEM_DATA_IN) {
 182                 fifo = _stm32_qspi_read_fifo;
 183                 buf = op->data.buf.in;
 184
 185         } else {
 186                 fifo = _stm32_qspi_write_fifo;
 187                 buf = (u8 *)op->data.buf.out;
 188         }
 189
 190         while (len--) {
 191                 ret = readl_poll_timeout(&priv->regs->sr, sr,
 192                                          sr & STM32_QSPI_SR_FTF,
 193                                          STM32_QSPI_FIFO_TIMEOUT_US);
 194                 if (ret) {
 195                         pr_err("fifo timeout (len:%d stat:%#x)\n", len, sr);
 196                         return ret;
 197                 }
 198
 199                 fifo(buf++, &priv->regs->dr);
 200         }
 201
 202         return 0;
 203 }
 204
 205 static int stm32_qspi_mm(struct stm32_qspi_priv *priv,
 206                          const struct spi_mem_op *op)
 207 {
 208         memcpy_fromio(op->data.buf.in, priv->mm_base + op->addr.val,
 209                       op->data.nbytes);
 210
 211         return 0;
 212 }
 213
 214 static int _stm32_qspi_tx(struct stm32_qspi_priv *priv,
 215                           const struct spi_mem_op *op,
 216                           u8 mode)
 217 {
 218         if (!op->data.nbytes)
 219                 return 0;
 220
 221         if (mode == STM32_QSPI_CCR_MEM_MAP)
 222                 return stm32_qspi_mm(priv, op);
 223
 224         return _stm32_qspi_poll(priv, op);
 225 }
 226
 227 static int _stm32_qspi_get_mode(u8 buswidth)
 228 {
 229         if (buswidth == 4)
 230                 return 3;
 231
 232         return buswidth;
 233 }
 234
 235 static int stm32_qspi_exec_op(struct spi_slave *slave,
 236                               const struct spi_mem_op *op)
 237 {
 238         struct stm32_qspi_priv *priv = dev_get_priv(slave->dev->parent);
 239         u32 cr, ccr, addr_max;
 240         u8 mode = STM32_QSPI_CCR_IND_WRITE;
 241         int timeout, ret;
 242
 243         debug("%s: cmd:%#x mode:%d.%d.%d.%d addr:%#llx len:%#x\n",
 244               __func__, op->cmd.opcode, op->cmd.buswidth, op->addr.buswidth,
 245               op->dummy.buswidth, op->data.buswidth,
 246               op->addr.val, op->data.nbytes);
 247
 248         ret = _stm32_qspi_wait_for_not_busy(priv);
 249         if (ret)
 250                 return ret;
 251
 252         addr_max = op->addr.val + op->data.nbytes + 1;
 253
 254         if (op->data.dir == SPI_MEM_DATA_IN && op->data.nbytes) {
 255                 if (addr_max < priv->mm_size && op->addr.buswidth)
 256                         mode = STM32_QSPI_CCR_MEM_MAP;
 257                 else
 258                         mode = STM32_QSPI_CCR_IND_READ;
 259         }
 260
 261         if (op->data.nbytes)
 262                 writel(op->data.nbytes - 1, &priv->regs->dlr);
 263
 264         ccr = (mode << STM32_QSPI_CCR_FMODE_SHIFT);
 265         ccr |= op->cmd.opcode;
 266         ccr |= (_stm32_qspi_get_mode(op->cmd.buswidth)
 267                 << STM32_QSPI_CCR_IMODE_SHIFT);
 268
 269         if (op->addr.nbytes) {
 270                 ccr |= ((op->addr.nbytes - 1) << STM32_QSPI_CCR_ADSIZE_SHIFT);
 271                 ccr |= (_stm32_qspi_get_mode(op->addr.buswidth)
 272                         << STM32_QSPI_CCR_ADMODE_SHIFT);
 273         }
 274
 275         if (op->dummy.buswidth && op->dummy.nbytes)
 276                 ccr |= (op->dummy.nbytes * 8 / op->dummy.buswidth
 277                         << STM32_QSPI_CCR_DCYC_SHIFT);
 278
 279         if (op->data.nbytes)
 280                 ccr |= (_stm32_qspi_get_mode(op->data.buswidth)
 281                         << STM32_QSPI_CCR_DMODE_SHIFT);
 282
 283         writel(ccr, &priv->regs->ccr);
 284
 285         if (op->addr.nbytes && mode != STM32_QSPI_CCR_MEM_MAP)
 286                 writel(op->addr.val, &priv->regs->ar);
 287
 288         ret = _stm32_qspi_tx(priv, op, mode);
 289         /*
 290          * Abort in:
 291          * -error case
 292          * -read memory map: prefetching must be stopped if we read the last
 293          *  byte of device (device size - fifo size). like device size is not
 294          *  knows, the prefetching is always stop.
 295          */
 296         if (ret || mode == STM32_QSPI_CCR_MEM_MAP)
 297                 goto abort;
 298
 299         /* Wait end of tx in indirect mode */
 300         ret = _stm32_qspi_wait_cmd(priv, op);
 301         if (ret)
 302                 goto abort;
 303
 304         return 0;
 305
 306 abort:
 307         setbits_le32(&priv->regs->cr, STM32_QSPI_CR_ABORT);
 308
 309         /* Wait clear of abort bit by hw */
 310         timeout = readl_poll_timeout(&priv->regs->cr, cr,
 311                                      !(cr & STM32_QSPI_CR_ABORT),
 312                                      STM32_ABT_TIMEOUT_US);
 313
 314         writel(STM32_QSPI_FCR_CTCF, &priv->regs->fcr);
 315
 316         if (ret || timeout)
 317                 pr_err("%s ret:%d abort timeout:%d\n", __func__, ret, timeout);
 318
 319         return ret;
 320 }
 321
 322 static int stm32_qspi_probe(struct udevice *bus)
 323 {
 324         struct stm32_qspi_priv *priv = dev_get_priv(bus);
 325         struct resource res;
 326         struct clk clk;
 327         struct reset_ctl reset_ctl;
 328         int ret;
 329
 330         ret = dev_read_resource_byname(bus, "qspi", &res);
 331         if (ret) {
 332                 dev_err(bus, "can't get regs base addresses(ret = %d)!\n", ret);
 333                 return ret;
 334         }
 335
 336         priv->regs = (struct stm32_qspi_regs *)res.start;
 337
 338         ret = dev_read_resource_byname(bus, "qspi_mm", &res);
 339         if (ret) {
 340                 dev_err(bus, "can't get mmap base address(ret = %d)!\n", ret);
 341                 return ret;
 342         }
 343
 344         priv->mm_base = (void __iomem *)res.start;
 345
 346         priv->mm_size = resource_size(&res);
 347         if (priv->mm_size > STM32_QSPI_MAX_MMAP_SZ)
 348                 return -EINVAL;
 349
 350         debug("%s: regs=<0x%p> mapped=<0x%p> mapped_size=<0x%lx>\n",
 351               __func__, priv->regs, priv->mm_base, priv->mm_size);
 352
 353         ret = clk_get_by_index(bus, 0, &clk);
 354         if (ret < 0)
 355                 return ret;
 356
 357         ret = clk_enable(&clk);
 358         if (ret) {
 359                 dev_err(bus, "failed to enable clock\n");
 360                 return ret;
 361         }
 362
 363         priv->clock_rate = clk_get_rate(&clk);
 364         if (!priv->clock_rate) {
 365                 clk_disable(&clk);
 366                 return -EINVAL;
 367         }
 368
 369         ret = reset_get_by_index(bus, 0, &reset_ctl);
 370         if (ret) {
 371                 if (ret != -ENOENT) {
 372                         dev_err(bus, "failed to get reset\n");
 373                         clk_disable(&clk);
 374                         return ret;
 375                 }
 376         } else {
 377                 /* Reset QSPI controller */
 378                 reset_assert(&reset_ctl);
 379                 udelay(2);
 380                 reset_deassert(&reset_ctl);
 381         }
 382
 383         priv->cs_used = -1;
 384
 385         setbits_le32(&priv->regs->cr, STM32_QSPI_CR_SSHIFT);
 386
 387         /* Set dcr fsize to max address */
 388         setbits_le32(&priv->regs->dcr,
 389                      STM32_QSPI_DCR_FSIZE_MASK << STM32_QSPI_DCR_FSIZE_SHIFT);
 390
 391         return 0;
 392 }
 393
 394 static int stm32_qspi_claim_bus(struct udevice *dev)
 395 {
 396         struct stm32_qspi_priv *priv = dev_get_priv(dev->parent);
 397         struct dm_spi_slave_platdata *slave_plat = dev_get_parent_platdata(dev);
 398         int slave_cs = slave_plat->cs;
 399
 400         if (slave_cs >= STM32_QSPI_MAX_CHIP)
 401                 return -ENODEV;
 402
 403         if (priv->cs_used != slave_cs) {
 404                 struct stm32_qspi_flash *flash = &priv->flash[slave_cs];
 405
 406                 priv->cs_used = slave_cs;
 407
 408                 if (flash->initialized) {
 409                         /* Set the configuration: speed + cs */
 410                         writel(flash->cr, &priv->regs->cr);
 411                         writel(flash->dcr, &priv->regs->dcr);
 412                 } else {
 413                         /* Set chip select */
 414                         clrsetbits_le32(&priv->regs->cr, STM32_QSPI_CR_FSEL,
 415                                         priv->cs_used ? STM32_QSPI_CR_FSEL : 0);
 416
 417                         /* Save the configuration: speed + cs */
 418                         flash->cr = readl(&priv->regs->cr);
 419                         flash->dcr = readl(&priv->regs->dcr);
 420
 421                         flash->initialized = true;
 422                 }
 423         }
 424
 425         setbits_le32(&priv->regs->cr, STM32_QSPI_CR_EN);
 426
 427         return 0;
 428 }
 429
 430 static int stm32_qspi_release_bus(struct udevice *dev)
 431 {
 432         struct stm32_qspi_priv *priv = dev_get_priv(dev->parent);
 433
 434         clrbits_le32(&priv->regs->cr, STM32_QSPI_CR_EN);
 435
 436         return 0;
 437 }
 438
 439 static int stm32_qspi_set_speed(struct udevice *bus, uint speed)
 440 {
 441         struct stm32_qspi_priv *priv = dev_get_priv(bus);
 442         u32 qspi_clk = priv->clock_rate;
 443         u32 prescaler = 255;
 444         u32 csht;
 445         int ret;
 446
 447         if (speed > 0) {
 448                 prescaler = 0;
 449                 if (qspi_clk) {
 450                         prescaler = DIV_ROUND_UP(qspi_clk, speed) - 1;
 451                         if (prescaler > 255)
 452                                 prescaler = 255;
 453                 }
 454         }
 455
 456         csht = DIV_ROUND_UP((5 * qspi_clk) / (prescaler + 1), 100000000);
 457         csht = (csht - 1) & STM32_QSPI_DCR_CSHT_MASK;
 458
 459         ret = _stm32_qspi_wait_for_not_busy(priv);
 460         if (ret)
 461                 return ret;
 462
 463         clrsetbits_le32(&priv->regs->cr,
 464                         STM32_QSPI_CR_PRESCALER_MASK <<
 465                         STM32_QSPI_CR_PRESCALER_SHIFT,
 466                         prescaler << STM32_QSPI_CR_PRESCALER_SHIFT);
 467
 468         clrsetbits_le32(&priv->regs->dcr,
 469                         STM32_QSPI_DCR_CSHT_MASK << STM32_QSPI_DCR_CSHT_SHIFT,
 470                         csht << STM32_QSPI_DCR_CSHT_SHIFT);
 471
 472         debug("%s: regs=%p, speed=%d\n", __func__, priv->regs,
 473               (qspi_clk / (prescaler + 1)));
 474
 475         return 0;
 476 }
 477
 478 static int stm32_qspi_set_mode(struct udevice *bus, uint mode)
 479 {
 480         struct stm32_qspi_priv *priv = dev_get_priv(bus);
 481         int ret;
 482
 483         ret = _stm32_qspi_wait_for_not_busy(priv);
 484         if (ret)
 485                 return ret;
 486
 487         if ((mode & SPI_CPHA) && (mode & SPI_CPOL))
 488                 setbits_le32(&priv->regs->dcr, STM32_QSPI_DCR_CKMODE);
 489         else if (!(mode & SPI_CPHA) && !(mode & SPI_CPOL))
 490                 clrbits_le32(&priv->regs->dcr, STM32_QSPI_DCR_CKMODE);
 491         else
 492                 return -ENODEV;
 493
 494         if (mode & SPI_CS_HIGH)
 495                 return -ENODEV;
 496
 497         debug("%s: regs=%p, mode=%d rx: ", __func__, priv->regs, mode);
 498
 499         if (mode & SPI_RX_QUAD)
 500                 debug("quad, tx: ");
 501         else if (mode & SPI_RX_DUAL)
 502                 debug("dual, tx: ");
 503         else
 504                 debug("single, tx: ");
 505
 506         if (mode & SPI_TX_QUAD)
 507                 debug("quad\n");
 508         else if (mode & SPI_TX_DUAL)
 509                 debug("dual\n");
 510         else
 511                 debug("single\n");
 512
 513         return 0;
 514 }
 515
 516 static const struct spi_controller_mem_ops stm32_qspi_mem_ops = {
 517         .exec_op = stm32_qspi_exec_op,
 518 };
 519
 520 static const struct dm_spi_ops stm32_qspi_ops = {
 521         .claim_bus      = stm32_qspi_claim_bus,
 522         .release_bus    = stm32_qspi_release_bus,
 523         .set_speed      = stm32_qspi_set_speed,
 524         .set_mode       = stm32_qspi_set_mode,
 525         .mem_ops        = &stm32_qspi_mem_ops,
 526 };
 527
 528 static const struct udevice_id stm32_qspi_ids[] = {
 529         { .compatible = "st,stm32f469-qspi" },
 530         { }
 531 };
 532
 533 U_BOOT_DRIVER(stm32_qspi) = {
 534         .name = "stm32_qspi",
 535         .id = UCLASS_SPI,
 536         .of_match = stm32_qspi_ids,
 537         .ops = &stm32_qspi_ops,
 538         .priv_auto_alloc_size = sizeof(struct stm32_qspi_priv),
 539         .probe = stm32_qspi_probe,
 540 };