drivers/mtd/nand/jz4740_nand.c

   1 /*
   2  *  Copyright (C) 2009-2010, Lars-Peter Clausen <lars@metafoo.de>
   3  *  JZ4740 SoC NAND controller driver
   4  *
   5  *  This program is free software; you can redistribute it and/or modify it
   6  *  under  the terms of the GNU General  Public License as published by the
   7  *  Free Software Foundation;  either version 2 of the License, or (at your
   8  *  option) any later version.
   9  *
  10  *  You should have received a copy of the GNU General Public License along
  11  *  with this program; if not, write to the Free Software Foundation, Inc.,
  12  *  675 Mass Ave, Cambridge, MA 02139, USA.
  13  *
  14  */
  15
  16 #include <linux/ioport.h>
  17 #include <linux/kernel.h>
  18 #include <linux/module.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/slab.h>
  21
  22 #include <linux/mtd/mtd.h>
  23 #include <linux/mtd/nand.h>
  24 #include <linux/mtd/partitions.h>
  25
  26 #include <linux/gpio.h>
  27
  28 #include <asm/mach-jz4740/jz4740_nand.h>
  29
  30 #define JZ_REG_NAND_CTRL        0x50
  31 #define JZ_REG_NAND_ECC_CTRL    0x100
  32 #define JZ_REG_NAND_DATA        0x104
  33 #define JZ_REG_NAND_PAR0        0x108
  34 #define JZ_REG_NAND_PAR1        0x10C
  35 #define JZ_REG_NAND_PAR2        0x110
  36 #define JZ_REG_NAND_IRQ_STAT    0x114
  37 #define JZ_REG_NAND_IRQ_CTRL    0x118
  38 #define JZ_REG_NAND_ERR(x)      (0x11C + ((x) << 2))
  39
  40 #define JZ_NAND_ECC_CTRL_PAR_READY      BIT(4)
  41 #define JZ_NAND_ECC_CTRL_ENCODING       BIT(3)
  42 #define JZ_NAND_ECC_CTRL_RS             BIT(2)
  43 #define JZ_NAND_ECC_CTRL_RESET          BIT(1)
  44 #define JZ_NAND_ECC_CTRL_ENABLE         BIT(0)
  45
  46 #define JZ_NAND_STATUS_ERR_COUNT        (BIT(31) | BIT(30) | BIT(29))
  47 #define JZ_NAND_STATUS_PAD_FINISH       BIT(4)
  48 #define JZ_NAND_STATUS_DEC_FINISH       BIT(3)
  49 #define JZ_NAND_STATUS_ENC_FINISH       BIT(2)
  50 #define JZ_NAND_STATUS_UNCOR_ERROR      BIT(1)
  51 #define JZ_NAND_STATUS_ERROR            BIT(0)
  52
  53 #define JZ_NAND_CTRL_ENABLE_CHIP(x) BIT((x) << 1)
  54 #define JZ_NAND_CTRL_ASSERT_CHIP(x) BIT(((x) << 1) + 1)
  55
  56 #define JZ_NAND_MEM_ADDR_OFFSET 0x10000
  57 #define JZ_NAND_MEM_CMD_OFFSET 0x08000
  58
  59 struct jz_nand {
  60         struct mtd_info mtd;
  61         struct nand_chip chip;
  62         void __iomem *base;
  63         struct resource *mem;
  64
  65         void __iomem *bank_base;
  66         struct resource *bank_mem;
  67
  68         struct jz_nand_platform_data *pdata;
  69         bool is_reading;
  70 };
  71
  72 static inline struct jz_nand *mtd_to_jz_nand(struct mtd_info *mtd)
  73 {
  74         return container_of(mtd, struct jz_nand, mtd);
  75 }
  76
  77 static void jz_nand_cmd_ctrl(struct mtd_info *mtd, int dat, unsigned int ctrl)
  78 {
  79         struct jz_nand *nand = mtd_to_jz_nand(mtd);
  80         struct nand_chip *chip = mtd->priv;
  81         uint32_t reg;
  82
  83         if (ctrl & NAND_CTRL_CHANGE) {
  84                 BUG_ON((ctrl & NAND_ALE) && (ctrl & NAND_CLE));
  85                 if (ctrl & NAND_ALE)
  86                         chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_ADDR_OFFSET;
  87                 else if (ctrl & NAND_CLE)
  88                         chip->IO_ADDR_W = nand->bank_base + JZ_NAND_MEM_CMD_OFFSET;
  89                 else
  90                         chip->IO_ADDR_W = nand->bank_base;
  91
  92                 reg = readl(nand->base + JZ_REG_NAND_CTRL);
  93                 if (ctrl & NAND_NCE)
  94                         reg |= JZ_NAND_CTRL_ASSERT_CHIP(0);
  95                 else
  96                         reg &= ~JZ_NAND_CTRL_ASSERT_CHIP(0);
  97                 writel(reg, nand->base + JZ_REG_NAND_CTRL);
  98         }
  99         if (dat != NAND_CMD_NONE)
 100                 writeb(dat, chip->IO_ADDR_W);
 101 }
 102
 103 static int jz_nand_dev_ready(struct mtd_info *mtd)
 104 {
 105         struct jz_nand *nand = mtd_to_jz_nand(mtd);
 106         return gpio_get_value_cansleep(nand->pdata->busy_gpio);
 107 }
 108
 109 static void jz_nand_hwctl(struct mtd_info *mtd, int mode)
 110 {
 111         struct jz_nand *nand = mtd_to_jz_nand(mtd);
 112         uint32_t reg;
 113
 114         writel(0, nand->base + JZ_REG_NAND_IRQ_STAT);
 115         reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
 116
 117         reg |= JZ_NAND_ECC_CTRL_RESET;
 118         reg |= JZ_NAND_ECC_CTRL_ENABLE;
 119         reg |= JZ_NAND_ECC_CTRL_RS;
 120
 121         switch (mode) {
 122         case NAND_ECC_READ:
 123                 reg &= ~JZ_NAND_ECC_CTRL_ENCODING;
 124                 nand->is_reading = true;
 125                 break;
 126         case NAND_ECC_WRITE:
 127                 reg |= JZ_NAND_ECC_CTRL_ENCODING;
 128                 nand->is_reading = false;
 129                 break;
 130         default:
 131                 break;
 132         }
 133
 134         writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
 135 }
 136
 137 static int jz_nand_calculate_ecc_rs(struct mtd_info *mtd, const uint8_t *dat,
 138         uint8_t *ecc_code)
 139 {
 140         struct jz_nand *nand = mtd_to_jz_nand(mtd);
 141         uint32_t reg, status;
 142         int i;
 143         unsigned int timeout = 1000;
 144         static uint8_t empty_block_ecc[] = {0xcd, 0x9d, 0x90, 0x58, 0xf4,
 145                                                 0x8b, 0xff, 0xb7, 0x6f};
 146
 147         if (nand->is_reading)
 148                 return 0;
 149
 150         do {
 151                 status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
 152         } while (!(status & JZ_NAND_STATUS_ENC_FINISH) && --timeout);
 153
 154         if (timeout == 0)
 155             return -1;
 156
 157         reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
 158         reg &= ~JZ_NAND_ECC_CTRL_ENABLE;
 159         writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
 160
 161         for (i = 0; i < 9; ++i)
 162                 ecc_code[i] = readb(nand->base + JZ_REG_NAND_PAR0 + i);
 163
 164         /* If the written data is completly 0xff, we also want to write 0xff as
 165          * ecc, otherwise we will get in trouble when doing subpage writes. */
 166         if (memcmp(ecc_code, empty_block_ecc, 9) == 0)
 167                 memset(ecc_code, 0xff, 9);
 168
 169         return 0;
 170 }
 171
 172 static void jz_nand_correct_data(uint8_t *dat, int index, int mask)
 173 {
 174         int offset = index & 0x7;
 175         uint16_t data;
 176
 177         index += (index >> 3);
 178
 179         data = dat[index];
 180         data |= dat[index+1] << 8;
 181
 182         mask ^= (data >> offset) & 0x1ff;
 183         data &= ~(0x1ff << offset);
 184         data |= (mask << offset);
 185
 186         dat[index] = data & 0xff;
 187         dat[index+1] = (data >> 8) & 0xff;
 188 }
 189
 190 static int jz_nand_correct_ecc_rs(struct mtd_info *mtd, uint8_t *dat,
 191         uint8_t *read_ecc, uint8_t *calc_ecc)
 192 {
 193         struct jz_nand *nand = mtd_to_jz_nand(mtd);
 194         int i, error_count, index;
 195         uint32_t reg, status, error;
 196         uint32_t t;
 197         unsigned int timeout = 1000;
 198
 199         t = read_ecc[0];
 200
 201         if (t == 0xff) {
 202                 for (i = 1; i < 9; ++i)
 203                         t &= read_ecc[i];
 204
 205                 t &= dat[0];
 206                 t &= dat[nand->chip.ecc.size / 2];
 207                 t &= dat[nand->chip.ecc.size - 1];
 208
 209                 if (t == 0xff) {
 210                         for (i = 1; i < nand->chip.ecc.size - 1; ++i)
 211                                 t &= dat[i];
 212                         if (t == 0xff)
 213                                 return 0;
 214                 }
 215         }
 216
 217         for (i = 0; i < 9; ++i)
 218                 writeb(read_ecc[i], nand->base + JZ_REG_NAND_PAR0 + i);
 219
 220         reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
 221         reg |= JZ_NAND_ECC_CTRL_PAR_READY;
 222         writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
 223
 224         do {
 225                 status = readl(nand->base + JZ_REG_NAND_IRQ_STAT);
 226         } while (!(status & JZ_NAND_STATUS_DEC_FINISH) && --timeout);
 227
 228         if (timeout == 0)
 229             return -1;
 230
 231         reg = readl(nand->base + JZ_REG_NAND_ECC_CTRL);
 232         reg &= ~JZ_NAND_ECC_CTRL_ENABLE;
 233         writel(reg, nand->base + JZ_REG_NAND_ECC_CTRL);
 234
 235         if (status & JZ_NAND_STATUS_ERROR) {
 236                 if (status & JZ_NAND_STATUS_UNCOR_ERROR)
 237                         return -1;
 238
 239                 error_count = (status & JZ_NAND_STATUS_ERR_COUNT) >> 29;
 240
 241                 for (i = 0; i < error_count; ++i) {
 242                         error = readl(nand->base + JZ_REG_NAND_ERR(i));
 243                         index = ((error >> 16) & 0x1ff) - 1;
 244                         if (index >= 0 && index < 512)
 245                                 jz_nand_correct_data(dat, index, error & 0x1ff);
 246                 }
 247
 248                 return error_count;
 249         }
 250
 251         return 0;
 252 }
 253
 254
 255 /* Copy paste of nand_read_page_hwecc_oob_first except for different eccpos
 256  * handling. The ecc area is for 4k chips 72 bytes long and thus does not fit
 257  * into the eccpos array. */
 258 static int jz_nand_read_page_hwecc_oob_first(struct mtd_info *mtd,
 259         struct nand_chip *chip, uint8_t *buf, int page)
 260 {
 261         int i, eccsize = chip->ecc.size;
 262         int eccbytes = chip->ecc.bytes;
 263         int eccsteps = chip->ecc.steps;
 264         uint8_t *p = buf;
 265         unsigned int ecc_offset = chip->page_shift;
 266
 267         /* Read the OOB area first */
 268         chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
 269         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
 270         chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
 271
 272         for (i = ecc_offset; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 273                 int stat;
 274
 275                 chip->ecc.hwctl(mtd, NAND_ECC_READ);
 276                 chip->read_buf(mtd, p, eccsize);
 277
 278                 stat = chip->ecc.correct(mtd, p, &chip->oob_poi[i], NULL);
 279                 if (stat < 0)
 280                         mtd->ecc_stats.failed++;
 281                 else
 282                         mtd->ecc_stats.corrected += stat;
 283         }
 284         return 0;
 285 }
 286
 287 /* Copy-and-paste of nand_write_page_hwecc with different eccpos handling. */
 288 static void jz_nand_write_page_hwecc(struct mtd_info *mtd,
 289         struct nand_chip *chip, const uint8_t *buf)
 290 {
 291         int i, eccsize = chip->ecc.size;
 292         int eccbytes = chip->ecc.bytes;
 293         int eccsteps = chip->ecc.steps;
 294         const uint8_t *p = buf;
 295         unsigned int ecc_offset = chip->page_shift;
 296
 297         for (i = ecc_offset; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
 298                 chip->ecc.hwctl(mtd, NAND_ECC_WRITE);
 299                 chip->write_buf(mtd, p, eccsize);
 300                 chip->ecc.calculate(mtd, p, &chip->oob_poi[i]);
 301         }
 302
 303         chip->write_buf(mtd, chip->oob_poi, mtd->oobsize);
 304 }
 305
 306 #ifdef CONFIG_MTD_CMDLINE_PARTS
 307 static const char *part_probes[] = {"cmdline", NULL};
 308 #endif
 309
 310 static int jz_nand_ioremap_resource(struct platform_device *pdev,
 311         const char *name, struct resource **res, void __iomem **base)
 312 {
 313         int ret;
 314
 315         *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 316         if (!*res) {
 317                 dev_err(&pdev->dev, "Failed to get platform %s memory\n", name);
 318                 ret = -ENXIO;
 319                 goto err;
 320         }
 321
 322         *res = request_mem_region((*res)->start, resource_size(*res),
 323                                 pdev->name);
 324         if (!*res) {
 325                 dev_err(&pdev->dev, "Failed to request %s memory region\n", name);
 326                 ret = -EBUSY;
 327                 goto err;
 328         }
 329
 330         *base = ioremap((*res)->start, resource_size(*res));
 331         if (!*base) {
 332                 dev_err(&pdev->dev, "Failed to ioremap %s memory region\n", name);
 333                 ret = -EBUSY;
 334                 goto err_release_mem;
 335         }
 336
 337         return 0;
 338
 339 err_release_mem:
 340         release_mem_region((*res)->start, resource_size(*res));
 341 err:
 342         *res = NULL;
 343         *base = NULL;
 344         return ret;
 345 }
 346
 347 static int __devinit jz_nand_probe(struct platform_device *pdev)
 348 {
 349         int ret;
 350         struct jz_nand *nand;
 351         struct nand_chip *chip;
 352         struct mtd_info *mtd;
 353         struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
 354 #ifdef CONFIG_MTD_PARTITIONS
 355         struct mtd_partition *partition_info;
 356         int num_partitions = 0;
 357 #endif
 358
 359         nand = kzalloc(sizeof(*nand), GFP_KERNEL);
 360         if (!nand) {
 361                 dev_err(&pdev->dev, "Failed to allocate device structure.\n");
 362                 return -ENOMEM;
 363         }
 364
 365         ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
 366         if (ret)
 367                 goto err_free;
 368         ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem,
 369                         &nand->bank_base);
 370         if (ret)
 371                 goto err_iounmap_mmio;
 372
 373         if (pdata && gpio_is_valid(pdata->busy_gpio)) {
 374                 ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
 375                 if (ret) {
 376                         dev_err(&pdev->dev,
 377                                 "Failed to request busy gpio %d: %d\n",
 378                                 pdata->busy_gpio, ret);
 379                         goto err_iounmap_mem;
 380                 }
 381         }
 382
 383         mtd             = &nand->mtd;
 384         chip            = &nand->chip;
 385         mtd->priv       = chip;
 386         mtd->owner      = THIS_MODULE;
 387         mtd->name       = "jz4740-nand";
 388
 389         chip->ecc.hwctl         = jz_nand_hwctl;
 390         chip->ecc.calculate     = jz_nand_calculate_ecc_rs;
 391         chip->ecc.correct       = jz_nand_correct_ecc_rs;
 392         chip->ecc.mode          = NAND_ECC_HW_OOB_FIRST;
 393         chip->ecc.size          = 512;
 394         chip->ecc.bytes         = 9;
 395
 396         chip->ecc.read_page     = jz_nand_read_page_hwecc_oob_first;
 397         chip->ecc.write_page    = jz_nand_write_page_hwecc;
 398
 399         if (pdata)
 400                 chip->ecc.layout = pdata->ecc_layout;
 401
 402         chip->chip_delay = 50;
 403         chip->cmd_ctrl = jz_nand_cmd_ctrl;
 404
 405         if (pdata && gpio_is_valid(pdata->busy_gpio))
 406                 chip->dev_ready = jz_nand_dev_ready;
 407
 408         chip->IO_ADDR_R = nand->bank_base;
 409         chip->IO_ADDR_W = nand->bank_base;
 410
 411         nand->pdata = pdata;
 412         platform_set_drvdata(pdev, nand);
 413
 414         writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL);
 415
 416         ret = nand_scan_ident(mtd, 1, NULL);
 417         if (ret) {
 418                 dev_err(&pdev->dev,  "Failed to scan nand\n");
 419                 goto err_gpio_free;
 420         }
 421
 422         if (pdata && pdata->ident_callback) {
 423                 pdata->ident_callback(pdev, chip, &pdata->partitions,
 424                                         &pdata->num_partitions);
 425         }
 426
 427         ret = nand_scan_tail(mtd);
 428         if (ret) {
 429                 dev_err(&pdev->dev,  "Failed to scan nand\n");
 430                 goto err_gpio_free;
 431         }
 432
 433 #ifdef CONFIG_MTD_PARTITIONS
 434 #ifdef CONFIG_MTD_CMDLINE_PARTS
 435         num_partitions = parse_mtd_partitions(mtd, part_probes,
 436                                                 &partition_info, 0);
 437 #endif
 438         if (num_partitions <= 0 && pdata) {
 439                 num_partitions = pdata->num_partitions;
 440                 partition_info = pdata->partitions;
 441         }
 442
 443         if (num_partitions > 0)
 444                 ret = add_mtd_partitions(mtd, partition_info, num_partitions);
 445         else
 446 #endif
 447         ret = add_mtd_device(mtd);
 448
 449         if (ret) {
 450                 dev_err(&pdev->dev, "Failed to add mtd device\n");
 451                 goto err_nand_release;
 452         }
 453
 454         dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");
 455
 456         return 0;
 457
 458 err_nand_release:
 459         nand_release(&nand->mtd);
 460 err_gpio_free:
 461         platform_set_drvdata(pdev, NULL);
 462         gpio_free(pdata->busy_gpio);
 463 err_iounmap_mem:
 464         iounmap(nand->bank_base);
 465 err_iounmap_mmio:
 466         iounmap(nand->base);
 467 err_free:
 468         kfree(nand);
 469         return ret;
 470 }
 471
 472 static int __devexit jz_nand_remove(struct platform_device *pdev)
 473 {
 474         struct jz_nand *nand = platform_get_drvdata(pdev);
 475
 476         nand_release(&nand->mtd);
 477
 478         /* Deassert and disable all chips */
 479         writel(0, nand->base + JZ_REG_NAND_CTRL);
 480
 481         iounmap(nand->bank_base);
 482         release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem));
 483         iounmap(nand->base);
 484         release_mem_region(nand->mem->start, resource_size(nand->mem));
 485
 486         platform_set_drvdata(pdev, NULL);
 487         kfree(nand);
 488
 489         return 0;
 490 }
 491
 492 struct platform_driver jz_nand_driver = {
 493         .probe = jz_nand_probe,
 494         .remove = __devexit_p(jz_nand_remove),
 495         .driver = {
 496                 .name = "jz4740-nand",
 497                 .owner = THIS_MODULE,
 498         },
 499 };
 500
 501 static int __init jz_nand_init(void)
 502 {
 503         return platform_driver_register(&jz_nand_driver);
 504 }
 505 module_init(jz_nand_init);
 506
 507 static void __exit jz_nand_exit(void)
 508 {
 509         platform_driver_unregister(&jz_nand_driver);
 510 }
 511 module_exit(jz_nand_exit);
 512
 513 MODULE_LICENSE("GPL");
 514 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 515 MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
 516 MODULE_ALIAS("platform:jz4740-nand");