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 nand_chip chip;
  59        void __iomem *reg;
  60        struct clk *clk;
  61        spinlock_t lock;
  62};
  63
  64static inline struct nuc900_nand *mtd_to_nuc900(struct mtd_info *mtd)
  65{
  66        return container_of(mtd_to_nand(mtd), struct nuc900_nand, chip);
  67}
  68
  69static const struct mtd_partition partitions[] = {
  70        {
  71         .name = "NAND FS 0",
  72         .offset = 0,
  73         .size = 8 * 1024 * 1024
  74        },
  75        {
  76         .name = "NAND FS 1",
  77         .offset = MTDPART_OFS_APPEND,
  78         .size = MTDPART_SIZ_FULL
  79        }
  80};
  81
  82static unsigned char nuc900_nand_read_byte(struct mtd_info *mtd)
  83{
  84        unsigned char ret;
  85        struct nuc900_nand *nand = mtd_to_nuc900(mtd);
  86
  87        ret = (unsigned char)read_data_reg(nand);
  88
  89        return ret;
  90}
  91
  92static void nuc900_nand_read_buf(struct mtd_info *mtd,
  93                                 unsigned char *buf, int len)
  94{
  95        int i;
  96        struct nuc900_nand *nand = mtd_to_nuc900(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 = mtd_to_nuc900(mtd);
 107
 108        for (i = 0; i < len; i++)
 109                write_data_reg(nand, buf[i]);
 110}
 111
 112static int nuc900_check_rb(struct nuc900_nand *nand)
 113{
 114        unsigned int val;
 115        spin_lock(&nand->lock);
 116        val = __raw_readl(nand->reg + REG_SMISR);
 117        val &= READYBUSY;
 118        spin_unlock(&nand->lock);
 119
 120        return val;
 121}
 122
 123static int nuc900_nand_devready(struct mtd_info *mtd)
 124{
 125        struct nuc900_nand *nand = mtd_to_nuc900(mtd);
 126        int ready;
 127
 128        ready = (nuc900_check_rb(nand)) ? 1 : 0;
 129        return ready;
 130}
 131
 132static void nuc900_nand_command_lp(struct mtd_info *mtd, unsigned int command,
 133                                   int column, int page_addr)
 134{
 135        register struct nand_chip *chip = mtd_to_nand(mtd);
 136        struct nuc900_nand *nand = mtd_to_nuc900(mtd);
 137
 138        if (command == NAND_CMD_READOOB) {
 139                column += mtd->writesize;
 140                command = NAND_CMD_READ0;
 141        }
 142
 143        write_cmd_reg(nand, command & 0xff);
 144
 145        if (column != -1 || page_addr != -1) {
 146
 147                if (column != -1) {
 148                        if (chip->options & NAND_BUSWIDTH_16 &&
 149                                        !nand_opcode_8bits(command))
 150                                column >>= 1;
 151                        write_addr_reg(nand, column);
 152                        write_addr_reg(nand, column >> 8 | ENDADDR);
 153                }
 154                if (page_addr != -1) {
 155                        write_addr_reg(nand, page_addr);
 156
 157                        if (chip->chipsize > (128 << 20)) {
 158                                write_addr_reg(nand, page_addr >> 8);
 159                                write_addr_reg(nand, page_addr >> 16 | ENDADDR);
 160                        } else {
 161                                write_addr_reg(nand, page_addr >> 8 | ENDADDR);
 162                        }
 163                }
 164        }
 165
 166        switch (command) {
 167        case NAND_CMD_CACHEDPROG:
 168        case NAND_CMD_PAGEPROG:
 169        case NAND_CMD_ERASE1:
 170        case NAND_CMD_ERASE2:
 171        case NAND_CMD_SEQIN:
 172        case NAND_CMD_RNDIN:
 173        case NAND_CMD_STATUS:
 174                return;
 175
 176        case NAND_CMD_RESET:
 177                if (chip->dev_ready)
 178                        break;
 179                udelay(chip->chip_delay);
 180
 181                write_cmd_reg(nand, NAND_CMD_STATUS);
 182                write_cmd_reg(nand, command);
 183
 184                while (!nuc900_check_rb(nand))
 185                        ;
 186
 187                return;
 188
 189        case NAND_CMD_RNDOUT:
 190                write_cmd_reg(nand, NAND_CMD_RNDOUTSTART);
 191                return;
 192
 193        case NAND_CMD_READ0:
 194
 195                write_cmd_reg(nand, NAND_CMD_READSTART);
 196        default:
 197
 198                if (!chip->dev_ready) {
 199                        udelay(chip->chip_delay);
 200                        return;
 201                }
 202        }
 203
 204        /* Apply this short delay always to ensure that we do wait tWB in
 205         * any case on any machine. */
 206        ndelay(100);
 207
 208        while (!chip->dev_ready(mtd))
 209                ;
 210}
 211
 212
 213static void nuc900_nand_enable(struct nuc900_nand *nand)
 214{
 215        unsigned int val;
 216        spin_lock(&nand->lock);
 217        __raw_writel(RESET_FMI, (nand->reg + REG_FMICSR));
 218
 219        val = __raw_readl(nand->reg + REG_FMICSR);
 220
 221        if (!(val & NAND_EN))
 222                __raw_writel(val | NAND_EN, nand->reg + REG_FMICSR);
 223
 224        val = __raw_readl(nand->reg + REG_SMCSR);
 225
 226        val &= ~(SWRST|PSIZE|DMARWEN|BUSWID|ECC4EN|NANDCS);
 227        val |= WP;
 228
 229        __raw_writel(val, nand->reg + REG_SMCSR);
 230
 231        spin_unlock(&nand->lock);
 232}
 233
 234static int nuc900_nand_probe(struct platform_device *pdev)
 235{
 236        struct nuc900_nand *nuc900_nand;
 237        struct nand_chip *chip;
 238        struct mtd_info *mtd;
 239        struct resource *res;
 240
 241        nuc900_nand = devm_kzalloc(&pdev->dev, sizeof(struct nuc900_nand),
 242                                   GFP_KERNEL);
 243        if (!nuc900_nand)
 244                return -ENOMEM;
 245        chip = &(nuc900_nand->chip);
 246        mtd = nand_to_mtd(chip);
 247
 248        mtd->dev.parent         = &pdev->dev;
 249        spin_lock_init(&nuc900_nand->lock);
 250
 251        nuc900_nand->clk = devm_clk_get(&pdev->dev, NULL);
 252        if (IS_ERR(nuc900_nand->clk))
 253                return -ENOENT;
 254        clk_enable(nuc900_nand->clk);
 255
 256        chip->cmdfunc           = nuc900_nand_command_lp;
 257        chip->dev_ready         = nuc900_nand_devready;
 258        chip->read_byte         = nuc900_nand_read_byte;
 259        chip->write_buf         = nuc900_nand_write_buf;
 260        chip->read_buf          = nuc900_nand_read_buf;
 261        chip->chip_delay        = 50;
 262        chip->options           = 0;
 263        chip->ecc.mode          = NAND_ECC_SOFT;
 264
 265        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 266        nuc900_nand->reg = devm_ioremap_resource(&pdev->dev, res);
 267        if (IS_ERR(nuc900_nand->reg))
 268                return PTR_ERR(nuc900_nand->reg);
 269
 270        nuc900_nand_enable(nuc900_nand);
 271
 272        if (nand_scan(mtd, 1))
 273                return -ENXIO;
 274
 275        mtd_device_register(mtd, partitions, ARRAY_SIZE(partitions));
 276
 277        platform_set_drvdata(pdev, nuc900_nand);
 278
 279        return 0;
 280}
 281
 282static int nuc900_nand_remove(struct platform_device *pdev)
 283{
 284        struct nuc900_nand *nuc900_nand = platform_get_drvdata(pdev);
 285
 286        nand_release(nand_to_mtd(&nuc900_nand->chip));
 287        clk_disable(nuc900_nand->clk);
 288
 289        return 0;
 290}
 291
 292static struct platform_driver nuc900_nand_driver = {
 293        .probe          = nuc900_nand_probe,
 294        .remove         = nuc900_nand_remove,
 295        .driver         = {
 296                .name   = "nuc900-fmi",
 297        },
 298};
 299
 300module_platform_driver(nuc900_nand_driver);
 301
 302MODULE_AUTHOR("Wan ZongShun <mcuos.com@gmail.com>");
 303MODULE_DESCRIPTION("w90p910/NUC9xx nand driver!");
 304MODULE_LICENSE("GPL");
 305MODULE_ALIAS("platform:nuc900-fmi");
 306