drivers/mtd/nand/ndfc.c

   1 /*
   2  *  drivers/mtd/ndfc.c
   3  *
   4  *  Overview:
   5  *   Platform independent driver for NDFC (NanD Flash Controller)
   6  *   integrated into EP440 cores
   7  *
   8  *   Ported to an OF platform driver by Sean MacLennan
   9  *
  10  *   The NDFC supports multiple chips, but this driver only supports a
  11  *   single chip since I do not have access to any boards with
  12  *   multiple chips.
  13  *
  14  *  Author: Thomas Gleixner
  15  *
  16  *  Copyright 2006 IBM
  17  *  Copyright 2008 PIKA Technologies
  18  *    Sean MacLennan <smaclennan@pikatech.com>
  19  *
  20  *  This program is free software; you can redistribute  it and/or modify it
  21  *  under  the terms of  the GNU General  Public License as published by the
  22  *  Free Software Foundation;  either version 2 of the  License, or (at your
  23  *  option) any later version.
  24  *
  25  */
  26 #include <linux/module.h>
  27 #include <linux/mtd/nand.h>
  28 #include <linux/mtd/nand_ecc.h>
  29 #include <linux/mtd/partitions.h>
  30 #include <linux/mtd/ndfc.h>
  31 #include <linux/slab.h>
  32 #include <linux/mtd/mtd.h>
  33 #include <linux/of_platform.h>
  34 #include <asm/io.h>
  35
  36
  37 struct ndfc_controller {
  38         struct platform_device *ofdev;
  39         void __iomem *ndfcbase;
  40         struct mtd_info mtd;
  41         struct nand_chip chip;
  42         int chip_select;
  43         struct nand_hw_control ndfc_control;
  44 #ifdef CONFIG_MTD_PARTITIONS
  45         struct mtd_partition *parts;
  46 #endif
  47 };
  48
  49 static struct ndfc_controller ndfc_ctrl;
  50
  51 static void ndfc_select_chip(struct mtd_info *mtd, int chip)
  52 {
  53         uint32_t ccr;
  54         struct ndfc_controller *ndfc = &ndfc_ctrl;
  55
  56         ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
  57         if (chip >= 0) {
  58                 ccr &= ~NDFC_CCR_BS_MASK;
  59                 ccr |= NDFC_CCR_BS(chip + ndfc->chip_select);
  60         } else
  61                 ccr |= NDFC_CCR_RESET_CE;
  62         out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
  63 }
  64
  65 static void ndfc_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  66 {
  67         struct ndfc_controller *ndfc = &ndfc_ctrl;
  68
  69         if (cmd == NAND_CMD_NONE)
  70                 return;
  71
  72         if (ctrl & NAND_CLE)
  73                 writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_CMD);
  74         else
  75                 writel(cmd & 0xFF, ndfc->ndfcbase + NDFC_ALE);
  76 }
  77
  78 static int ndfc_ready(struct mtd_info *mtd)
  79 {
  80         struct ndfc_controller *ndfc = &ndfc_ctrl;
  81
  82         return in_be32(ndfc->ndfcbase + NDFC_STAT) & NDFC_STAT_IS_READY;
  83 }
  84
  85 static void ndfc_enable_hwecc(struct mtd_info *mtd, int mode)
  86 {
  87         uint32_t ccr;
  88         struct ndfc_controller *ndfc = &ndfc_ctrl;
  89
  90         ccr = in_be32(ndfc->ndfcbase + NDFC_CCR);
  91         ccr |= NDFC_CCR_RESET_ECC;
  92         out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
  93         wmb();
  94 }
  95
  96 static int ndfc_calculate_ecc(struct mtd_info *mtd,
  97                               const u_char *dat, u_char *ecc_code)
  98 {
  99         struct ndfc_controller *ndfc = &ndfc_ctrl;
 100         uint32_t ecc;
 101         uint8_t *p = (uint8_t *)&ecc;
 102
 103         wmb();
 104         ecc = in_be32(ndfc->ndfcbase + NDFC_ECC);
 105         /* The NDFC uses Smart Media (SMC) bytes order */
 106         ecc_code[0] = p[1];
 107         ecc_code[1] = p[2];
 108         ecc_code[2] = p[3];
 109
 110         return 0;
 111 }
 112
 113 /*
 114  * Speedups for buffer read/write/verify
 115  *
 116  * NDFC allows 32bit read/write of data. So we can speed up the buffer
 117  * functions. No further checking, as nand_base will always read/write
 118  * page aligned.
 119  */
 120 static void ndfc_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
 121 {
 122         struct ndfc_controller *ndfc = &ndfc_ctrl;
 123         uint32_t *p = (uint32_t *) buf;
 124
 125         for(;len > 0; len -= 4)
 126                 *p++ = in_be32(ndfc->ndfcbase + NDFC_DATA);
 127 }
 128
 129 static void ndfc_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 130 {
 131         struct ndfc_controller *ndfc = &ndfc_ctrl;
 132         uint32_t *p = (uint32_t *) buf;
 133
 134         for(;len > 0; len -= 4)
 135                 out_be32(ndfc->ndfcbase + NDFC_DATA, *p++);
 136 }
 137
 138 static int ndfc_verify_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
 139 {
 140         struct ndfc_controller *ndfc = &ndfc_ctrl;
 141         uint32_t *p = (uint32_t *) buf;
 142
 143         for(;len > 0; len -= 4)
 144                 if (*p++ != in_be32(ndfc->ndfcbase + NDFC_DATA))
 145                         return -EFAULT;
 146         return 0;
 147 }
 148
 149 /*
 150  * Initialize chip structure
 151  */
 152 static int ndfc_chip_init(struct ndfc_controller *ndfc,
 153                           struct device_node *node)
 154 {
 155 #ifdef CONFIG_MTD_PARTITIONS
 156 #ifdef CONFIG_MTD_CMDLINE_PARTS
 157         static const char *part_types[] = { "cmdlinepart", NULL };
 158 #else
 159         static const char *part_types[] = { NULL };
 160 #endif
 161 #endif
 162         struct device_node *flash_np;
 163         struct nand_chip *chip = &ndfc->chip;
 164         int ret;
 165
 166         chip->IO_ADDR_R = ndfc->ndfcbase + NDFC_DATA;
 167         chip->IO_ADDR_W = ndfc->ndfcbase + NDFC_DATA;
 168         chip->cmd_ctrl = ndfc_hwcontrol;
 169         chip->dev_ready = ndfc_ready;
 170         chip->select_chip = ndfc_select_chip;
 171         chip->chip_delay = 50;
 172         chip->controller = &ndfc->ndfc_control;
 173         chip->read_buf = ndfc_read_buf;
 174         chip->write_buf = ndfc_write_buf;
 175         chip->verify_buf = ndfc_verify_buf;
 176         chip->ecc.correct = nand_correct_data;
 177         chip->ecc.hwctl = ndfc_enable_hwecc;
 178         chip->ecc.calculate = ndfc_calculate_ecc;
 179         chip->ecc.mode = NAND_ECC_HW;
 180         chip->ecc.size = 256;
 181         chip->ecc.bytes = 3;
 182
 183         ndfc->mtd.priv = chip;
 184         ndfc->mtd.owner = THIS_MODULE;
 185
 186         flash_np = of_get_next_child(node, NULL);
 187         if (!flash_np)
 188                 return -ENODEV;
 189
 190         ndfc->mtd.name = kasprintf(GFP_KERNEL, "%s.%s",
 191                         dev_name(&ndfc->ofdev->dev), flash_np->name);
 192         if (!ndfc->mtd.name) {
 193                 ret = -ENOMEM;
 194                 goto err;
 195         }
 196
 197         ret = nand_scan(&ndfc->mtd, 1);
 198         if (ret)
 199                 goto err;
 200
 201 #ifdef CONFIG_MTD_PARTITIONS
 202         ret = parse_mtd_partitions(&ndfc->mtd, part_types, &ndfc->parts, 0);
 203         if (ret < 0)
 204                 goto err;
 205
 206 #ifdef CONFIG_MTD_OF_PARTS
 207         if (ret == 0) {
 208                 ret = of_mtd_parse_partitions(&ndfc->ofdev->dev, flash_np,
 209                                               &ndfc->parts);
 210                 if (ret < 0)
 211                         goto err;
 212         }
 213 #endif
 214
 215         if (ret > 0)
 216                 ret = add_mtd_partitions(&ndfc->mtd, ndfc->parts, ret);
 217         else
 218 #endif
 219                 ret = add_mtd_device(&ndfc->mtd);
 220
 221 err:
 222         of_node_put(flash_np);
 223         if (ret)
 224                 kfree(ndfc->mtd.name);
 225         return ret;
 226 }
 227
 228 static int __devinit ndfc_probe(struct platform_device *ofdev,
 229                                 const struct of_device_id *match)
 230 {
 231         struct ndfc_controller *ndfc = &ndfc_ctrl;
 232         const __be32 *reg;
 233         u32 ccr;
 234         int err, len;
 235
 236         spin_lock_init(&ndfc->ndfc_control.lock);
 237         init_waitqueue_head(&ndfc->ndfc_control.wq);
 238         ndfc->ofdev = ofdev;
 239         dev_set_drvdata(&ofdev->dev, ndfc);
 240
 241         /* Read the reg property to get the chip select */
 242         reg = of_get_property(ofdev->dev.of_node, "reg", &len);
 243         if (reg == NULL || len != 12) {
 244                 dev_err(&ofdev->dev, "unable read reg property (%d)\n", len);
 245                 return -ENOENT;
 246         }
 247         ndfc->chip_select = be32_to_cpu(reg[0]);
 248
 249         ndfc->ndfcbase = of_iomap(ofdev->dev.of_node, 0);
 250         if (!ndfc->ndfcbase) {
 251                 dev_err(&ofdev->dev, "failed to get memory\n");
 252                 return -EIO;
 253         }
 254
 255         ccr = NDFC_CCR_BS(ndfc->chip_select);
 256
 257         /* It is ok if ccr does not exist - just default to 0 */
 258         reg = of_get_property(ofdev->dev.of_node, "ccr", NULL);
 259         if (reg)
 260                 ccr |= be32_to_cpup(reg);
 261
 262         out_be32(ndfc->ndfcbase + NDFC_CCR, ccr);
 263
 264         /* Set the bank settings if given */
 265         reg = of_get_property(ofdev->dev.of_node, "bank-settings", NULL);
 266         if (reg) {
 267                 int offset = NDFC_BCFG0 + (ndfc->chip_select << 2);
 268                 out_be32(ndfc->ndfcbase + offset, be32_to_cpup(reg));
 269         }
 270
 271         err = ndfc_chip_init(ndfc, ofdev->dev.of_node);
 272         if (err) {
 273                 iounmap(ndfc->ndfcbase);
 274                 return err;
 275         }
 276
 277         return 0;
 278 }
 279
 280 static int __devexit ndfc_remove(struct platform_device *ofdev)
 281 {
 282         struct ndfc_controller *ndfc = dev_get_drvdata(&ofdev->dev);
 283
 284         nand_release(&ndfc->mtd);
 285
 286         return 0;
 287 }
 288
 289 static const struct of_device_id ndfc_match[] = {
 290         { .compatible = "ibm,ndfc", },
 291         {}
 292 };
 293 MODULE_DEVICE_TABLE(of, ndfc_match);
 294
 295 static struct of_platform_driver ndfc_driver = {
 296         .driver = {
 297                 .name = "ndfc",
 298                 .owner = THIS_MODULE,
 299                 .of_match_table = ndfc_match,
 300         },
 301         .probe = ndfc_probe,
 302         .remove = __devexit_p(ndfc_remove),
 303 };
 304
 305 static int __init ndfc_nand_init(void)
 306 {
 307         return of_register_platform_driver(&ndfc_driver);
 308 }
 309
 310 static void __exit ndfc_nand_exit(void)
 311 {
 312         of_unregister_platform_driver(&ndfc_driver);
 313 }
 314
 315 module_init(ndfc_nand_init);
 316 module_exit(ndfc_nand_exit);
 317
 318 MODULE_LICENSE("GPL");
 319 MODULE_AUTHOR("Thomas Gleixner <tglx@linutronix.de>");
 320 MODULE_DESCRIPTION("OF Platform driver for NDFC");