target/linux/ar71xx/files/drivers/mtd/nand/rb4xx_nand.c

   1 /*
   2  *  NAND flash driver for the MikroTik RouterBoard 4xx series
   3  *
   4  *  Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
   5  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
   6  *
   7  *  This file was based on the driver for Linux 2.6.22 published by
   8  *  MikroTik for their RouterBoard 4xx series devices.
   9  *
  10  *  This program is free software; you can redistribute it and/or modify it
  11  *  under the terms of the GNU General Public License version 2 as published
  12  *  by the Free Software Foundation.
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/mtd/nand.h>
  19 #include <linux/mtd/mtd.h>
  20 #include <linux/mtd/partitions.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/delay.h>
  23 #include <linux/io.h>
  24 #include <linux/gpio.h>
  25 #include <linux/slab.h>
  26 #include <linux/version.h>
  27
  28 #include <asm/mach-ath79/ath79.h>
  29 #include <asm/mach-ath79/rb4xx_cpld.h>
  30
  31 #define DRV_NAME        "rb4xx-nand"
  32 #define DRV_VERSION     "0.2.0"
  33 #define DRV_DESC        "NAND flash driver for RouterBoard 4xx series"
  34
  35 #define RB4XX_NAND_GPIO_READY   5
  36 #define RB4XX_NAND_GPIO_ALE     37
  37 #define RB4XX_NAND_GPIO_CLE     38
  38 #define RB4XX_NAND_GPIO_NCE     39
  39
  40 struct rb4xx_nand_info {
  41         struct nand_chip        chip;
  42 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
  43         struct mtd_info         mtd;
  44 #endif
  45 };
  46
  47 static inline struct rb4xx_nand_info *mtd_to_rbinfo(struct mtd_info *mtd)
  48 {
  49 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
  50         return container_of(mtd, struct rb4xx_nand_info, mtd);
  51 #else
  52         struct nand_chip *chip = mtd_to_nand(mtd);
  53
  54         return container_of(chip, struct rb4xx_nand_info, chip);
  55 #endif
  56 }
  57
  58 static struct mtd_info *rbinfo_to_mtd(struct rb4xx_nand_info *nfc)
  59 {
  60 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
  61         return &nfc->mtd;
  62 #else
  63         return nand_to_mtd(&nfc->chip);
  64 #endif
  65 }
  66
  67 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
  68 /*
  69  * We need to use the OLD Yaffs-1 OOB layout, otherwise the RB bootloader
  70  * will not be able to find the kernel that we load.
  71  */
  72 static struct nand_ecclayout rb4xx_nand_ecclayout = {
  73         .eccbytes       = 6,
  74         .eccpos         = { 8, 9, 10, 13, 14, 15 },
  75         .oobavail       = 9,
  76         .oobfree        = { { 0, 4 }, { 6, 2 }, { 11, 2 }, { 4, 1 } }
  77 };
  78
  79 #else
  80
  81 static int rb4xx_ooblayout_ecc(struct mtd_info *mtd, int section,
  82                                struct mtd_oob_region *oobregion)
  83 {
  84         switch (section) {
  85         case 0:
  86                 oobregion->offset = 8;
  87                 oobregion->length = 3;
  88                 return 0;
  89         case 1:
  90                 oobregion->offset = 13;
  91                 oobregion->length = 3;
  92                 return 0;
  93         default:
  94                 return -ERANGE;
  95         }
  96 }
  97
  98 static int rb4xx_ooblayout_free(struct mtd_info *mtd, int section,
  99                                 struct mtd_oob_region *oobregion)
 100 {
 101         switch (section) {
 102         case 0:
 103                 oobregion->offset = 0;
 104                 oobregion->length = 4;
 105                 return 0;
 106         case 1:
 107                 oobregion->offset = 4;
 108                 oobregion->length = 1;
 109                 return 0;
 110         case 2:
 111                 oobregion->offset = 6;
 112                 oobregion->length = 2;
 113                 return 0;
 114         case 3:
 115                 oobregion->offset = 11;
 116                 oobregion->length = 2;
 117                 return 0;
 118         default:
 119                 return -ERANGE;
 120         }
 121 }
 122
 123 static const struct mtd_ooblayout_ops rb4xx_nand_ecclayout_ops = {
 124         .ecc = rb4xx_ooblayout_ecc,
 125         .free = rb4xx_ooblayout_free,
 126 };
 127 #endif /* < 4.6 */
 128
 129 static struct mtd_partition rb4xx_nand_partitions[] = {
 130         {
 131                 .name   = "booter",
 132                 .offset = 0,
 133                 .size   = (256 * 1024),
 134                 .mask_flags = MTD_WRITEABLE,
 135         },
 136         {
 137                 .name   = "kernel",
 138                 .offset = (256 * 1024),
 139                 .size   = (4 * 1024 * 1024) - (256 * 1024),
 140         },
 141         {
 142                 .name   = "ubi",
 143                 .offset = MTDPART_OFS_NXTBLK,
 144                 .size   = MTDPART_SIZ_FULL,
 145         },
 146 };
 147
 148 static int rb4xx_nand_dev_ready(struct mtd_info *mtd)
 149 {
 150         return gpio_get_value_cansleep(RB4XX_NAND_GPIO_READY);
 151 }
 152
 153 static void rb4xx_nand_write_cmd(unsigned char cmd)
 154 {
 155         unsigned char data = cmd;
 156         int err;
 157
 158         err = rb4xx_cpld_write(&data, 1);
 159         if (err)
 160                 pr_err("rb4xx_nand: write cmd failed, err=%d\n", err);
 161 }
 162
 163 static void rb4xx_nand_cmd_ctrl(struct mtd_info *mtd, int cmd,
 164                                 unsigned int ctrl)
 165 {
 166         if (ctrl & NAND_CTRL_CHANGE) {
 167                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_CLE,
 168                                         (ctrl & NAND_CLE) ? 1 : 0);
 169                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_ALE,
 170                                         (ctrl & NAND_ALE) ? 1 : 0);
 171                 gpio_set_value_cansleep(RB4XX_NAND_GPIO_NCE,
 172                                         (ctrl & NAND_NCE) ? 0 : 1);
 173         }
 174
 175         if (cmd != NAND_CMD_NONE)
 176                 rb4xx_nand_write_cmd(cmd);
 177 }
 178
 179 static unsigned char rb4xx_nand_read_byte(struct mtd_info *mtd)
 180 {
 181         unsigned char data = 0;
 182         int err;
 183
 184         err = rb4xx_cpld_read(&data, 1);
 185         if (err) {
 186                 pr_err("rb4xx_nand: read data failed, err=%d\n", err);
 187                 data = 0xff;
 188         }
 189
 190         return data;
 191 }
 192
 193 static void rb4xx_nand_write_buf(struct mtd_info *mtd, const unsigned char *buf,
 194                                  int len)
 195 {
 196         int err;
 197
 198         err = rb4xx_cpld_write(buf, len);
 199         if (err)
 200                 pr_err("rb4xx_nand: write buf failed, err=%d\n", err);
 201 }
 202
 203 static void rb4xx_nand_read_buf(struct mtd_info *mtd, unsigned char *buf,
 204                                 int len)
 205 {
 206         int err;
 207
 208         err = rb4xx_cpld_read(buf, len);
 209         if (err)
 210                 pr_err("rb4xx_nand: read buf failed, err=%d\n", err);
 211 }
 212
 213 static int rb4xx_nand_probe(struct platform_device *pdev)
 214 {
 215         struct rb4xx_nand_info  *info;
 216         struct mtd_info *mtd;
 217         int ret;
 218
 219         printk(KERN_INFO DRV_DESC " version " DRV_VERSION "\n");
 220
 221         ret = gpio_request(RB4XX_NAND_GPIO_READY, "NAND RDY");
 222         if (ret) {
 223                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 224                         RB4XX_NAND_GPIO_READY);
 225                 goto err;
 226         }
 227
 228         ret = gpio_direction_input(RB4XX_NAND_GPIO_READY);
 229         if (ret) {
 230                 dev_err(&pdev->dev, "unable to set input mode on gpio %d\n",
 231                         RB4XX_NAND_GPIO_READY);
 232                 goto err_free_gpio_ready;
 233         }
 234
 235         ret = gpio_request(RB4XX_NAND_GPIO_ALE, "NAND ALE");
 236         if (ret) {
 237                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 238                         RB4XX_NAND_GPIO_ALE);
 239                 goto err_free_gpio_ready;
 240         }
 241
 242         ret = gpio_direction_output(RB4XX_NAND_GPIO_ALE, 0);
 243         if (ret) {
 244                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 245                         RB4XX_NAND_GPIO_ALE);
 246                 goto err_free_gpio_ale;
 247         }
 248
 249         ret = gpio_request(RB4XX_NAND_GPIO_CLE, "NAND CLE");
 250         if (ret) {
 251                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 252                         RB4XX_NAND_GPIO_CLE);
 253                 goto err_free_gpio_ale;
 254         }
 255
 256         ret = gpio_direction_output(RB4XX_NAND_GPIO_CLE, 0);
 257         if (ret) {
 258                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 259                         RB4XX_NAND_GPIO_CLE);
 260                 goto err_free_gpio_cle;
 261         }
 262
 263         ret = gpio_request(RB4XX_NAND_GPIO_NCE, "NAND NCE");
 264         if (ret) {
 265                 dev_err(&pdev->dev, "unable to request gpio %d\n",
 266                         RB4XX_NAND_GPIO_NCE);
 267                 goto err_free_gpio_cle;
 268         }
 269
 270         ret = gpio_direction_output(RB4XX_NAND_GPIO_NCE, 1);
 271         if (ret) {
 272                 dev_err(&pdev->dev, "unable to set output mode on gpio %d\n",
 273                         RB4XX_NAND_GPIO_ALE);
 274                 goto err_free_gpio_nce;
 275         }
 276
 277         info = kzalloc(sizeof(*info), GFP_KERNEL);
 278         if (!info) {
 279                 dev_err(&pdev->dev, "rb4xx-nand: no memory for private data\n");
 280                 ret = -ENOMEM;
 281                 goto err_free_gpio_nce;
 282         }
 283
 284         info->chip.priv = &info;
 285         mtd = rbinfo_to_mtd(info);
 286
 287 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
 288         mtd->priv       = &info->chip;
 289 #endif
 290         mtd->owner      = THIS_MODULE;
 291
 292         info->chip.cmd_ctrl     = rb4xx_nand_cmd_ctrl;
 293         info->chip.dev_ready    = rb4xx_nand_dev_ready;
 294         info->chip.read_byte    = rb4xx_nand_read_byte;
 295         info->chip.write_buf    = rb4xx_nand_write_buf;
 296         info->chip.read_buf     = rb4xx_nand_read_buf;
 297
 298         info->chip.chip_delay   = 25;
 299         info->chip.ecc.mode     = NAND_ECC_SOFT;
 300 #if LINUX_VERSION_CODE >= KERNEL_VERSION(4,6,0)
 301         info->chip.ecc.algo = NAND_ECC_HAMMING;
 302 #endif
 303         info->chip.options = NAND_NO_SUBPAGE_WRITE;
 304
 305         platform_set_drvdata(pdev, info);
 306
 307         ret = nand_scan_ident(mtd, 1, NULL);
 308         if (ret) {
 309                 ret = -ENXIO;
 310                 goto err_free_info;
 311         }
 312
 313         if (mtd->writesize == 512)
 314 #if LINUX_VERSION_CODE < KERNEL_VERSION(4,6,0)
 315                 info->chip.ecc.layout = &rb4xx_nand_ecclayout;
 316 #else
 317                 mtd_set_ooblayout(mtd, &rb4xx_nand_ecclayout_ops);
 318 #endif
 319
 320         ret = nand_scan_tail(mtd);
 321         if (ret) {
 322                 return -ENXIO;
 323                 goto err_set_drvdata;
 324         }
 325
 326         mtd_device_register(mtd, rb4xx_nand_partitions,
 327                                 ARRAY_SIZE(rb4xx_nand_partitions));
 328         if (ret)
 329                 goto err_release_nand;
 330
 331         return 0;
 332
 333 err_release_nand:
 334         nand_release(mtd);
 335 err_set_drvdata:
 336         platform_set_drvdata(pdev, NULL);
 337 err_free_info:
 338         kfree(info);
 339 err_free_gpio_nce:
 340         gpio_free(RB4XX_NAND_GPIO_NCE);
 341 err_free_gpio_cle:
 342         gpio_free(RB4XX_NAND_GPIO_CLE);
 343 err_free_gpio_ale:
 344         gpio_free(RB4XX_NAND_GPIO_ALE);
 345 err_free_gpio_ready:
 346         gpio_free(RB4XX_NAND_GPIO_READY);
 347 err:
 348         return ret;
 349 }
 350
 351 static int rb4xx_nand_remove(struct platform_device *pdev)
 352 {
 353         struct rb4xx_nand_info *info = platform_get_drvdata(pdev);
 354
 355         nand_release(rbinfo_to_mtd(info));
 356         platform_set_drvdata(pdev, NULL);
 357         kfree(info);
 358         gpio_free(RB4XX_NAND_GPIO_NCE);
 359         gpio_free(RB4XX_NAND_GPIO_CLE);
 360         gpio_free(RB4XX_NAND_GPIO_ALE);
 361         gpio_free(RB4XX_NAND_GPIO_READY);
 362
 363         return 0;
 364 }
 365
 366 static struct platform_driver rb4xx_nand_driver = {
 367         .probe  = rb4xx_nand_probe,
 368         .remove = rb4xx_nand_remove,
 369         .driver = {
 370                 .name   = DRV_NAME,
 371                 .owner  = THIS_MODULE,
 372         },
 373 };
 374
 375 static int __init rb4xx_nand_init(void)
 376 {
 377         return platform_driver_register(&rb4xx_nand_driver);
 378 }
 379
 380 static void __exit rb4xx_nand_exit(void)
 381 {
 382         platform_driver_unregister(&rb4xx_nand_driver);
 383 }
 384
 385 module_init(rb4xx_nand_init);
 386 module_exit(rb4xx_nand_exit);
 387
 388 MODULE_DESCRIPTION(DRV_DESC);
 389 MODULE_VERSION(DRV_VERSION);
 390 MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 391 MODULE_AUTHOR("Imre Kaloz <kaloz@openwrt.org>");
 392 MODULE_LICENSE("GPL v2");