kernel/2.6.29.6-aldebaran-rt/drivers/mtd/nand/edb7312.c

   1 /*
   2  *  drivers/mtd/nand/edb7312.c
   3  *
   4  *  Copyright (C) 2002 Marius Gröger (mag@sysgo.de)
   5  *
   6  *  Derived from drivers/mtd/nand/autcpu12.c
   7  *       Copyright (c) 2001 Thomas Gleixner (gleixner@autronix.de)
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  *  Overview:
  14  *   This is a device driver for the NAND flash device found on the
  15  *   CLEP7312 board which utilizes the Toshiba TC58V64AFT part. This is
  16  *   a 64Mibit (8MiB x 8 bits) NAND flash device.
  17  */
  18
  19 #include <linux/slab.h>
  20 #include <linux/module.h>
  21 #include <linux/init.h>
  22 #include <linux/mtd/mtd.h>
  23 #include <linux/mtd/nand.h>
  24 #include <linux/mtd/partitions.h>
  25 #include <asm/io.h>
  26 #include <mach/hardware.h>      /* for CLPS7111_VIRT_BASE */
  27 #include <asm/sizes.h>
  28 #include <asm/hardware/clps7111.h>
  29
  30 /*
  31  * MTD structure for EDB7312 board
  32  */
  33 static struct mtd_info *ep7312_mtd = NULL;
  34
  35 /*
  36  * Values specific to the EDB7312 board (used with EP7312 processor)
  37  */
  38 #define EP7312_FIO_PBASE 0x10000000     /* Phys address of flash */
  39 #define EP7312_PXDR     0x0001  /*
  40                                  * IO offset to Port B data register
  41                                  * where the CLE, ALE and NCE pins
  42                                  * are wired to.
  43                                  */
  44 #define EP7312_PXDDR    0x0041  /*
  45                                  * IO offset to Port B data direction
  46                                  * register so we can control the IO
  47                                  * lines.
  48                                  */
  49
  50 /*
  51  * Module stuff
  52  */
  53
  54 static unsigned long ep7312_fio_pbase = EP7312_FIO_PBASE;
  55 static void __iomem *ep7312_pxdr = (void __iomem *)EP7312_PXDR;
  56 static void __iomem *ep7312_pxddr = (void __iomem *)EP7312_PXDDR;
  57
  58 #ifdef CONFIG_MTD_PARTITIONS
  59 /*
  60  * Define static partitions for flash device
  61  */
  62 static struct mtd_partition partition_info[] = {
  63         {.name = "EP7312 Nand Flash",
  64          .offset = 0,
  65          .size = 8 * 1024 * 1024}
  66 };
  67
  68 #define NUM_PARTITIONS 1
  69
  70 #endif
  71
  72 /*
  73  *      hardware specific access to control-lines
  74  *
  75  *      NAND_NCE: bit 0 -> bit 6 (bit 7 = 1)
  76  *      NAND_CLE: bit 1 -> bit 4
  77  *      NAND_ALE: bit 2 -> bit 5
  78  */
  79 static void ep7312_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  80 {
  81         struct nand_chip *chip = mtd->priv;
  82
  83         if (ctrl & NAND_CTRL_CHANGE) {
  84                 unsigned char bits = 0x80;
  85
  86                 bits |= (ctrl & (NAND_CLE | NAND_ALE)) << 3;
  87                 bits |= (ctrl & NAND_NCE) ? 0x00 : 0x40;
  88
  89                 clps_writeb((clps_readb(ep7312_pxdr)  & 0xF0) | bits,
  90                             ep7312_pxdr);
  91         }
  92         if (cmd != NAND_CMD_NONE)
  93                 writeb(cmd, chip->IO_ADDR_W);
  94 }
  95
  96 /*
  97  *      read device ready pin
  98  */
  99 static int ep7312_device_ready(struct mtd_info *mtd)
 100 {
 101         return 1;
 102 }
 103
 104 #ifdef CONFIG_MTD_PARTITIONS
 105 const char *part_probes[] = { "cmdlinepart", NULL };
 106 #endif
 107
 108 /*
 109  * Main initialization routine
 110  */
 111 static int __init ep7312_init(void)
 112 {
 113         struct nand_chip *this;
 114         const char *part_type = 0;
 115         int mtd_parts_nb = 0;
 116         struct mtd_partition *mtd_parts = 0;
 117         void __iomem *ep7312_fio_base;
 118
 119         /* Allocate memory for MTD device structure and private data */
 120         ep7312_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
 121         if (!ep7312_mtd) {
 122                 printk("Unable to allocate EDB7312 NAND MTD device structure.\n");
 123                 return -ENOMEM;
 124         }
 125
 126         /* map physical address */
 127         ep7312_fio_base = ioremap(ep7312_fio_pbase, SZ_1K);
 128         if (!ep7312_fio_base) {
 129                 printk("ioremap EDB7312 NAND flash failed\n");
 130                 kfree(ep7312_mtd);
 131                 return -EIO;
 132         }
 133
 134         /* Get pointer to private data */
 135         this = (struct nand_chip *)(&ep7312_mtd[1]);
 136
 137         /* Initialize structures */
 138         memset(ep7312_mtd, 0, sizeof(struct mtd_info));
 139         memset(this, 0, sizeof(struct nand_chip));
 140
 141         /* Link the private data with the MTD structure */
 142         ep7312_mtd->priv = this;
 143         ep7312_mtd->owner = THIS_MODULE;
 144
 145         /*
 146          * Set GPIO Port B control register so that the pins are configured
 147          * to be outputs for controlling the NAND flash.
 148          */
 149         clps_writeb(0xf0, ep7312_pxddr);
 150
 151         /* insert callbacks */
 152         this->IO_ADDR_R = ep7312_fio_base;
 153         this->IO_ADDR_W = ep7312_fio_base;
 154         this->cmd_ctrl = ep7312_hwcontrol;
 155         this->dev_ready = ep7312_device_ready;
 156         /* 15 us command delay time */
 157         this->chip_delay = 15;
 158
 159         /* Scan to find existence of the device */
 160         if (nand_scan(ep7312_mtd, 1)) {
 161                 iounmap((void *)ep7312_fio_base);
 162                 kfree(ep7312_mtd);
 163                 return -ENXIO;
 164         }
 165 #ifdef CONFIG_MTD_PARTITIONS
 166         ep7312_mtd->name = "edb7312-nand";
 167         mtd_parts_nb = parse_mtd_partitions(ep7312_mtd, part_probes, &mtd_parts, 0);
 168         if (mtd_parts_nb > 0)
 169                 part_type = "command line";
 170         else
 171                 mtd_parts_nb = 0;
 172 #endif
 173         if (mtd_parts_nb == 0) {
 174                 mtd_parts = partition_info;
 175                 mtd_parts_nb = NUM_PARTITIONS;
 176                 part_type = "static";
 177         }
 178
 179         /* Register the partitions */
 180         printk(KERN_NOTICE "Using %s partition definition\n", part_type);
 181         add_mtd_partitions(ep7312_mtd, mtd_parts, mtd_parts_nb);
 182
 183         /* Return happy */
 184         return 0;
 185 }
 186
 187 module_init(ep7312_init);
 188
 189 /*
 190  * Clean up routine
 191  */
 192 static void __exit ep7312_cleanup(void)
 193 {
 194         struct nand_chip *this = (struct nand_chip *)&ep7312_mtd[1];
 195
 196         /* Release resources, unregister device */
 197         nand_release(ap7312_mtd);
 198
 199         /* Release io resource */
 200         iounmap(this->IO_ADDR_R);
 201
 202         /* Free the MTD device structure */
 203         kfree(ep7312_mtd);
 204 }
 205
 206 module_exit(ep7312_cleanup);
 207
 208 MODULE_LICENSE("GPL");
 209 MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
 210 MODULE_DESCRIPTION("MTD map driver for Cogent EDB7312 board");