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 static int jz_nand_ioremap_resource(struct platform_device *pdev,
 255         const char *name, struct resource **res, void __iomem **base)
 256 {
 257         int ret;
 258
 259         *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
 260         if (!*res) {
 261                 dev_err(&pdev->dev, "Failed to get platform %s memory\n", name);
 262                 ret = -ENXIO;
 263                 goto err;
 264         }
 265
 266         *res = request_mem_region((*res)->start, resource_size(*res),
 267                                 pdev->name);
 268         if (!*res) {
 269                 dev_err(&pdev->dev, "Failed to request %s memory region\n", name);
 270                 ret = -EBUSY;
 271                 goto err;
 272         }
 273
 274         *base = ioremap((*res)->start, resource_size(*res));
 275         if (!*base) {
 276                 dev_err(&pdev->dev, "Failed to ioremap %s memory region\n", name);
 277                 ret = -EBUSY;
 278                 goto err_release_mem;
 279         }
 280
 281         return 0;
 282
 283 err_release_mem:
 284         release_mem_region((*res)->start, resource_size(*res));
 285 err:
 286         *res = NULL;
 287         *base = NULL;
 288         return ret;
 289 }
 290
 291 static int __devinit jz_nand_probe(struct platform_device *pdev)
 292 {
 293         int ret;
 294         struct jz_nand *nand;
 295         struct nand_chip *chip;
 296         struct mtd_info *mtd;
 297         struct jz_nand_platform_data *pdata = pdev->dev.platform_data;
 298
 299         nand = kzalloc(sizeof(*nand), GFP_KERNEL);
 300         if (!nand) {
 301                 dev_err(&pdev->dev, "Failed to allocate device structure.\n");
 302                 return -ENOMEM;
 303         }
 304
 305         ret = jz_nand_ioremap_resource(pdev, "mmio", &nand->mem, &nand->base);
 306         if (ret)
 307                 goto err_free;
 308         ret = jz_nand_ioremap_resource(pdev, "bank", &nand->bank_mem,
 309                         &nand->bank_base);
 310         if (ret)
 311                 goto err_iounmap_mmio;
 312
 313         if (pdata && gpio_is_valid(pdata->busy_gpio)) {
 314                 ret = gpio_request(pdata->busy_gpio, "NAND busy pin");
 315                 if (ret) {
 316                         dev_err(&pdev->dev,
 317                                 "Failed to request busy gpio %d: %d\n",
 318                                 pdata->busy_gpio, ret);
 319                         goto err_iounmap_mem;
 320                 }
 321         }
 322
 323         mtd             = &nand->mtd;
 324         chip            = &nand->chip;
 325         mtd->priv       = chip;
 326         mtd->owner      = THIS_MODULE;
 327         mtd->name       = "jz4740-nand";
 328
 329         chip->ecc.hwctl         = jz_nand_hwctl;
 330         chip->ecc.calculate     = jz_nand_calculate_ecc_rs;
 331         chip->ecc.correct       = jz_nand_correct_ecc_rs;
 332         chip->ecc.mode          = NAND_ECC_HW_OOB_FIRST;
 333         chip->ecc.size          = 512;
 334         chip->ecc.bytes         = 9;
 335
 336         if (pdata)
 337                 chip->ecc.layout = pdata->ecc_layout;
 338
 339         chip->chip_delay = 50;
 340         chip->cmd_ctrl = jz_nand_cmd_ctrl;
 341
 342         if (pdata && gpio_is_valid(pdata->busy_gpio))
 343                 chip->dev_ready = jz_nand_dev_ready;
 344
 345         chip->IO_ADDR_R = nand->bank_base;
 346         chip->IO_ADDR_W = nand->bank_base;
 347
 348         nand->pdata = pdata;
 349         platform_set_drvdata(pdev, nand);
 350
 351         writel(JZ_NAND_CTRL_ENABLE_CHIP(0), nand->base + JZ_REG_NAND_CTRL);
 352
 353         ret = nand_scan_ident(mtd, 1, NULL);
 354         if (ret) {
 355                 dev_err(&pdev->dev,  "Failed to scan nand\n");
 356                 goto err_gpio_free;
 357         }
 358
 359         if (pdata && pdata->ident_callback) {
 360                 pdata->ident_callback(pdev, chip, &pdata->partitions,
 361                                         &pdata->num_partitions);
 362         }
 363
 364         ret = nand_scan_tail(mtd);
 365         if (ret) {
 366                 dev_err(&pdev->dev,  "Failed to scan nand\n");
 367                 goto err_gpio_free;
 368         }
 369
 370         ret = mtd_device_parse_register(mtd, NULL, NULL,
 371                                         pdata ? pdata->partitions : NULL,
 372                                         pdata ? pdata->num_partitions : 0);
 373
 374         if (ret) {
 375                 dev_err(&pdev->dev, "Failed to add mtd device\n");
 376                 goto err_nand_release;
 377         }
 378
 379         dev_info(&pdev->dev, "Successfully registered JZ4740 NAND driver\n");
 380
 381         return 0;
 382
 383 err_nand_release:
 384         nand_release(&nand->mtd);
 385 err_gpio_free:
 386         platform_set_drvdata(pdev, NULL);
 387         gpio_free(pdata->busy_gpio);
 388 err_iounmap_mem:
 389         iounmap(nand->bank_base);
 390 err_iounmap_mmio:
 391         iounmap(nand->base);
 392 err_free:
 393         kfree(nand);
 394         return ret;
 395 }
 396
 397 static int __devexit jz_nand_remove(struct platform_device *pdev)
 398 {
 399         struct jz_nand *nand = platform_get_drvdata(pdev);
 400
 401         nand_release(&nand->mtd);
 402
 403         /* Deassert and disable all chips */
 404         writel(0, nand->base + JZ_REG_NAND_CTRL);
 405
 406         iounmap(nand->bank_base);
 407         release_mem_region(nand->bank_mem->start, resource_size(nand->bank_mem));
 408         iounmap(nand->base);
 409         release_mem_region(nand->mem->start, resource_size(nand->mem));
 410
 411         platform_set_drvdata(pdev, NULL);
 412         kfree(nand);
 413
 414         return 0;
 415 }
 416
 417 static struct platform_driver jz_nand_driver = {
 418         .probe = jz_nand_probe,
 419         .remove = __devexit_p(jz_nand_remove),
 420         .driver = {
 421                 .name = "jz4740-nand",
 422                 .owner = THIS_MODULE,
 423         },
 424 };
 425
 426 module_platform_driver(jz_nand_driver);
 427
 428 MODULE_LICENSE("GPL");
 429 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 430 MODULE_DESCRIPTION("NAND controller driver for JZ4740 SoC");
 431 MODULE_ALIAS("platform:jz4740-nand");