linux/drivers/mtd/nand/nuc900_nand.c
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   1/*
   2 * Copyright © 2009 Nuvoton technology corporation.
   3 *
   4 * Wan ZongShun <mcuos.com@gmail.com>
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License as published by
   8 * the Free Software Foundation;version 2 of the License.
   9 *
  10 */
  11
  12#include <linux/slab.h>
  13#include <linux/module.h>
  14#include <linux/interrupt.h>
  15#include <linux/io.h>
  16#include <linux/platform_device.h>
  17#include <linux/delay.h>
  18#include <linux/clk.h>
  19#include <linux/err.h>
  20
  21#include <linux/mtd/mtd.h>
  22#include <linux/mtd/nand.h>
  23#include <linux/mtd/partitions.h>
  24
  25#define REG_FMICSR      0x00
  26#define REG_SMCSR       0xa0
  27#define REG_SMISR       0xac
  28#define REG_SMCMD       0xb0
  29#define REG_SMADDR      0xb4
  30#define REG_SMDATA      0xb8
  31
  32#define RESET_FMI       0x01
  33#define NAND_EN         0x08
  34#define READYBUSY       (0x01 << 18)
  35
  36#define SWRST           0x01
  37#define PSIZE           (0x01 << 3)
  38#define DMARWEN         (0x03 << 1)
  39#define BUSWID          (0x01 << 4)
  40#define ECC4EN          (0x01 << 5)
  41#define WP              (0x01 << 24)
  42#define NANDCS          (0x01 << 25)
  43#define ENDADDR         (0x01 << 31)
  44
  45#define read_data_reg(dev)              \
  46        __raw_readl((dev)->reg + REG_SMDATA)
  47
  48#define write_data_reg(dev, val)        \
  49        __raw_writel((val), (dev)->reg + REG_SMDATA)
  50
  51#define write_cmd_reg(dev, val)         \
  52        __raw_writel((val), (dev)->reg + REG_SMCMD)
  53
  54#define write_addr_reg(dev, val)        \
  55        __raw_writel((val), (dev)->reg + REG_SMADDR)
  56
  57struct nuc900_nand {
  58        struct mtd_info mtd;
  59        struct nand_chip chip;
  60        void __iomem *reg;
  61        struct clk *clk;
  62        spinlock_t lock;
  63};
  64
  65static const struct mtd_partition partitions[] = {
  66        {
  67         .name = "NAND FS 0",
  68         .offset = 0,
  69         .size = 8 * 1024 * 1024
  70        },
  71        {
  72         .name = "NAND FS 1",
  73         .offset = MTDPART_OFS_APPEND,
  74         .size = MTDPART_SIZ_FULL
  75        }
  76};
  77
  78static unsigned char nuc900_nand_read_byte(struct mtd_info *mtd)
  79{
  80        unsigned char ret;
  81        struct nuc900_nand *nand;
  82
  83        nand = container_of(mtd, struct nuc900_nand, mtd);
  84
  85        ret = (unsigned char)read_data_reg(nand);
  86
  87        return ret;
  88}
  89
  90static void nuc900_nand_read_buf(struct mtd_info *mtd,
  91                                 unsigned char *buf, int len)
  92{
  93        int i;
  94        struct nuc900_nand *nand;
  95
  96        nand = container_of(mtd, struct nuc900_nand, mtd);
  97
  98        for (i = 0; i < len; i++)
  99                buf[i] = (unsigned char)read_data_reg(nand);
 100}
 101
 102static void nuc900_nand_write_buf(struct mtd_info *mtd,
 103                                  const unsigned char *buf, int len)
 104{
 105        int i;
 106        struct nuc900_nand *nand;
 107
 108        nand = container_of(mtd, struct nuc900_nand, mtd);
 109
 110        for (i = 0; i < len; i++)
 111                write_data_reg(nand, buf[i]);
 112}
 113
 114static int nuc900_check_rb(struct nuc900_nand *nand)
 115{
 116        unsigned int val;
 117        spin_lock(&nand->lock);
 118        val = __raw_readl(REG_SMISR);
 119        val &= READYBUSY;
 120        spin_unlock(&nand->lock);
 121
 122        return val;
 123}
 124
 125static int nuc900_nand_devready(struct mtd_info *mtd)
 126{
 127        struct nuc900_nand *nand;
 128        int ready;
 129
 130        nand = container_of(mtd, struct nuc900_nand, mtd);
 131
 132        ready = (nuc900_check_rb(nand)) ? 1 : 0;
 133        return ready;
 134}
 135
 136static void nuc900_nand_command_lp(struct mtd_info *mtd, unsigned int command,
 137                                   int column, int page_addr)
 138{
 139        register struct nand_chip *chip = mtd->priv;
 140        struct nuc900_nand *nand;
 141
 142        nand = container_of(mtd, struct nuc900_nand, mtd);
 143
 144        if (command == NAND_CMD_READOOB) {
 145                column += mtd->writesize;
 146                command = NAND_CMD_READ0;
 147        }
 148
 149        write_cmd_reg(nand, command & 0xff);
 150
 151        if (column != -1 || page_addr != -1) {
 152
 153                if (column != -1) {
 154                        if (chip->options & NAND_BUSWIDTH_16 &&
 155                                        !nand_opcode_8bits(command))
 156                                column >>= 1;
 157                        write_addr_reg(nand, column);
 158                        write_addr_reg(nand, column >> 8 | ENDADDR);
 159                }
 160                if (page_addr != -1) {
 161                        write_addr_reg(nand, page_addr);
 162
 163                        if (chip->chipsize > (128 << 20)) {
 164                                write_addr_reg(nand, page_addr >> 8);
 165                                write_addr_reg(nand, page_addr >> 16 | ENDADDR);
 166                        } else {
 167                                write_addr_reg(nand, page_addr >> 8 | ENDADDR);
 168                        }
 169                }
 170        }
 171
 172        switch (command) {
 173        case NAND_CMD_CACHEDPROG:
 174        case NAND_CMD_PAGEPROG:
 175        case NAND_CMD_ERASE1:
 176        case NAND_CMD_ERASE2:
 177        case NAND_CMD_SEQIN:
 178        case NAND_CMD_RNDIN:
 179        case NAND_CMD_STATUS:
 180                return;
 181
 182        case NAND_CMD_RESET:
 183                if (chip->dev_ready)
 184                        break;
 185                udelay(chip->chip_delay);
 186
 187                write_cmd_reg(nand, NAND_CMD_STATUS);
 188                write_cmd_reg(nand, command);
 189
 190                while (!nuc900_check_rb(nand))
 191                        ;
 192
 193                return;
 194
 195        case NAND_CMD_RNDOUT:
 196                write_cmd_reg(nand, NAND_CMD_RNDOUTSTART);
 197                return;
 198
 199        case NAND_CMD_READ0:
 200
 201                write_cmd_reg(nand, NAND_CMD_READSTART);
 202        default:
 203
 204                if (!chip->dev_ready) {
 205                        udelay(chip->chip_delay);
 206                        return;
 207                }
 208        }
 209
 210        /* Apply this short delay always to ensure that we do wait tWB in
 211         * any case on any machine. */
 212        ndelay(100);
 213
 214        while (!chip->dev_ready(mtd))
 215                ;
 216}
 217
 218
 219static void nuc900_nand_enable(struct nuc900_nand *nand)
 220{
 221        unsigned int val;
 222        spin_lock(&nand->lock);
 223        __raw_writel(RESET_FMI, (nand->reg + REG_FMICSR));
 224
 225        val = __raw_readl(nand->reg + REG_FMICSR);
 226
 227        if (!(val & NAND_EN))
 228                __raw_writel(val | NAND_EN, nand->reg + REG_FMICSR);
 229
 230        val = __raw_readl(nand->reg + REG_SMCSR);
 231
 232        val &= ~(SWRST|PSIZE|DMARWEN|BUSWID|ECC4EN|NANDCS);
 233        val |= WP;
 234
 235        __raw_writel(val, nand->reg + REG_SMCSR);
 236
 237        spin_unlock(&nand->lock);
 238}
 239
 240static int nuc900_nand_probe(struct platform_device *pdev)
 241{
 242        struct nuc900_nand *nuc900_nand;
 243        struct nand_chip *chip;
 244        struct resource *res;
 245
 246        nuc900_nand = devm_kzalloc(&pdev->dev, sizeof(struct nuc900_nand),
 247                                   GFP_KERNEL);
 248        if (!nuc900_nand)
 249                return -ENOMEM;
 250        chip = &(nuc900_nand->chip);
 251
 252        nuc900_nand->mtd.priv   = chip;
 253        nuc900_nand->mtd.owner  = THIS_MODULE;
 254        spin_lock_init(&nuc900_nand->lock);
 255
 256        nuc900_nand->clk = devm_clk_get(&pdev->dev, NULL);
 257        if (IS_ERR(nuc900_nand->clk))
 258                return -ENOENT;
 259        clk_enable(nuc900_nand->clk);
 260
 261        chip->cmdfunc           = nuc900_nand_command_lp;
 262        chip->dev_ready         = nuc900_nand_devready;
 263        chip->read_byte         = nuc900_nand_read_byte;
 264        chip->write_buf         = nuc900_nand_write_buf;
 265        chip->read_buf          = nuc900_nand_read_buf;
 266        chip->chip_delay        = 50;
 267        chip->options           = 0;
 268        chip->ecc.mode          = NAND_ECC_SOFT;
 269
 270        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 271        nuc900_nand->reg = devm_ioremap_resource(&pdev->dev, res);
 272        if (IS_ERR(nuc900_nand->reg))
 273                return PTR_ERR(nuc900_nand->reg);
 274
 275        nuc900_nand_enable(nuc900_nand);
 276
 277        if (nand_scan(&(nuc900_nand->mtd), 1))
 278                return -ENXIO;
 279
 280        mtd_device_register(&(nuc900_nand->mtd), partitions,
 281                            ARRAY_SIZE(partitions));
 282
 283        platform_set_drvdata(pdev, nuc900_nand);
 284
 285        return 0;
 286}
 287
 288static int nuc900_nand_remove(struct platform_device *pdev)
 289{
 290        struct nuc900_nand *nuc900_nand = platform_get_drvdata(pdev);
 291
 292        nand_release(&nuc900_nand->mtd);
 293        clk_disable(nuc900_nand->clk);
 294
 295        return 0;
 296}
 297
 298static struct platform_driver nuc900_nand_driver = {
 299        .probe          = nuc900_nand_probe,
 300        .remove         = nuc900_nand_remove,
 301        .driver         = {
 302                .name   = "nuc900-fmi",
 303                .owner  = THIS_MODULE,
 304        },
 305};
 306
 307module_platform_driver(nuc900_nand_driver);
 308
 309MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
 310MODULE_DESCRIPTION("w90p910/NUC9xx nand driver!");
 311MODULE_LICENSE("GPL");
 312MODULE_ALIAS("platform:nuc900-fmi");
 313