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 /*
  59  * Define static partitions for flash device
  60  */
  61 static struct mtd_partition partition_info[] = {
  62         {.name = "EP7312 Nand Flash",
  63          .offset = 0,
  64          .size = 8 * 1024 * 1024}
  65 };
  66
  67 #define NUM_PARTITIONS 1
  68
  69 /*
  70  *      hardware specific access to control-lines
  71  *
  72  *      NAND_NCE: bit 0 -> bit 6 (bit 7 = 1)
  73  *      NAND_CLE: bit 1 -> bit 4
  74  *      NAND_ALE: bit 2 -> bit 5
  75  */
  76 static void ep7312_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl)
  77 {
  78         struct nand_chip *chip = mtd->priv;
  79
  80         if (ctrl & NAND_CTRL_CHANGE) {
  81                 unsigned char bits = 0x80;
  82
  83                 bits |= (ctrl & (NAND_CLE | NAND_ALE)) << 3;
  84                 bits |= (ctrl & NAND_NCE) ? 0x00 : 0x40;
  85
  86                 clps_writeb((clps_readb(ep7312_pxdr)  & 0xF0) | bits,
  87                             ep7312_pxdr);
  88         }
  89         if (cmd != NAND_CMD_NONE)
  90                 writeb(cmd, chip->IO_ADDR_W);
  91 }
  92
  93 /*
  94  *      read device ready pin
  95  */
  96 static int ep7312_device_ready(struct mtd_info *mtd)
  97 {
  98         return 1;
  99 }
 100
 101 const char *part_probes[] = { "cmdlinepart", NULL };
 102
 103 /*
 104  * Main initialization routine
 105  */
 106 static int __init ep7312_init(void)
 107 {
 108         struct nand_chip *this;
 109         const char *part_type = 0;
 110         int mtd_parts_nb = 0;
 111         struct mtd_partition *mtd_parts = 0;
 112         void __iomem *ep7312_fio_base;
 113
 114         /* Allocate memory for MTD device structure and private data */
 115         ep7312_mtd = kmalloc(sizeof(struct mtd_info) + sizeof(struct nand_chip), GFP_KERNEL);
 116         if (!ep7312_mtd) {
 117                 printk("Unable to allocate EDB7312 NAND MTD device structure.\n");
 118                 return -ENOMEM;
 119         }
 120
 121         /* map physical address */
 122         ep7312_fio_base = ioremap(ep7312_fio_pbase, SZ_1K);
 123         if (!ep7312_fio_base) {
 124                 printk("ioremap EDB7312 NAND flash failed\n");
 125                 kfree(ep7312_mtd);
 126                 return -EIO;
 127         }
 128
 129         /* Get pointer to private data */
 130         this = (struct nand_chip *)(&ep7312_mtd[1]);
 131
 132         /* Initialize structures */
 133         memset(ep7312_mtd, 0, sizeof(struct mtd_info));
 134         memset(this, 0, sizeof(struct nand_chip));
 135
 136         /* Link the private data with the MTD structure */
 137         ep7312_mtd->priv = this;
 138         ep7312_mtd->owner = THIS_MODULE;
 139
 140         /*
 141          * Set GPIO Port B control register so that the pins are configured
 142          * to be outputs for controlling the NAND flash.
 143          */
 144         clps_writeb(0xf0, ep7312_pxddr);
 145
 146         /* insert callbacks */
 147         this->IO_ADDR_R = ep7312_fio_base;
 148         this->IO_ADDR_W = ep7312_fio_base;
 149         this->cmd_ctrl = ep7312_hwcontrol;
 150         this->dev_ready = ep7312_device_ready;
 151         /* 15 us command delay time */
 152         this->chip_delay = 15;
 153
 154         /* Scan to find existence of the device */
 155         if (nand_scan(ep7312_mtd, 1)) {
 156                 iounmap((void *)ep7312_fio_base);
 157                 kfree(ep7312_mtd);
 158                 return -ENXIO;
 159         }
 160         ep7312_mtd->name = "edb7312-nand";
 161         mtd_parts_nb = parse_mtd_partitions(ep7312_mtd, part_probes, &mtd_parts, 0);
 162         if (mtd_parts_nb > 0)
 163                 part_type = "command line";
 164         else
 165                 mtd_parts_nb = 0;
 166         if (mtd_parts_nb == 0) {
 167                 mtd_parts = partition_info;
 168                 mtd_parts_nb = NUM_PARTITIONS;
 169                 part_type = "static";
 170         }
 171
 172         /* Register the partitions */
 173         printk(KERN_NOTICE "Using %s partition definition\n", part_type);
 174         mtd_device_register(ep7312_mtd, mtd_parts, mtd_parts_nb);
 175
 176         /* Return happy */
 177         return 0;
 178 }
 179
 180 module_init(ep7312_init);
 181
 182 /*
 183  * Clean up routine
 184  */
 185 static void __exit ep7312_cleanup(void)
 186 {
 187         struct nand_chip *this = (struct nand_chip *)&ep7312_mtd[1];
 188
 189         /* Release resources, unregister device */
 190         nand_release(ap7312_mtd);
 191
 192         /* Release io resource */
 193         iounmap(this->IO_ADDR_R);
 194
 195         /* Free the MTD device structure */
 196         kfree(ep7312_mtd);
 197 }
 198
 199 module_exit(ep7312_cleanup);
 200
 201 MODULE_LICENSE("GPL");
 202 MODULE_AUTHOR("Marius Groeger <mag@sysgo.de>");
 203 MODULE_DESCRIPTION("MTD map driver for Cogent EDB7312 board");