drivers/mtd/maps/ixp4xx.c

   1 /*
   2  * $Id: ixp4xx.c,v 1.8 2005/09/08 10:32:20 dvrabel Exp $
   3  *
   4  * drivers/mtd/maps/ixp4xx.c
   5  *
   6  * MTD Map file for IXP4XX based systems. Please do not make per-board
   7  * changes in here. If your board needs special setup, do it in your
   8  * platform level code in arch/arm/mach-ixp4xx/board-setup.c
   9  *
  10  * Original Author: Intel Corporation
  11  * Maintainer: Deepak Saxena <dsaxena@mvista.com>
  12  *
  13  * Copyright (C) 2002 Intel Corporation
  14  * Copyright (C) 2003-2004 MontaVista Software, Inc.
  15  *
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/types.h>
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/string.h>
  23 #include <linux/slab.h>
  24 #include <linux/ioport.h>
  25 #include <linux/device.h>
  26 #include <linux/platform_device.h>
  27
  28 #include <linux/mtd/mtd.h>
  29 #include <linux/mtd/map.h>
  30 #include <linux/mtd/partitions.h>
  31
  32 #include <asm/io.h>
  33 #include <asm/mach/flash.h>
  34
  35 #include <linux/reboot.h>
  36
  37 #ifndef __ARMEB__
  38 #define BYTE0(h)        ((h) & 0xFF)
  39 #define BYTE1(h)        (((h) >> 8) & 0xFF)
  40 #else
  41 #define BYTE0(h)        (((h) >> 8) & 0xFF)
  42 #define BYTE1(h)        ((h) & 0xFF)
  43 #endif
  44
  45 static map_word ixp4xx_read16(struct map_info *map, unsigned long ofs)
  46 {
  47         map_word val;
  48         val.x[0] = *(__u16 *) (map->map_priv_1 + ofs);
  49         return val;
  50 }
  51
  52 /*
  53  * The IXP4xx expansion bus only allows 16-bit wide acceses
  54  * when attached to a 16-bit wide device (such as the 28F128J3A),
  55  * so we can't just memcpy_fromio().
  56  */
  57 static void ixp4xx_copy_from(struct map_info *map, void *to,
  58                              unsigned long from, ssize_t len)
  59 {
  60         int i;
  61         u8 *dest = (u8 *) to;
  62         u16 *src = (u16 *) (map->map_priv_1 + from);
  63         u16 data;
  64
  65         for (i = 0; i < (len / 2); i++) {
  66                 data = src[i];
  67                 dest[i * 2] = BYTE0(data);
  68                 dest[i * 2 + 1] = BYTE1(data);
  69         }
  70
  71         if (len & 1)
  72                 dest[len - 1] = BYTE0(src[i]);
  73 }
  74
  75 /*
  76  * Unaligned writes are ignored, causing the 8-bit
  77  * probe to fail and proceed to the 16-bit probe (which succeeds).
  78  */
  79 static void ixp4xx_probe_write16(struct map_info *map, map_word d, unsigned long adr)
  80 {
  81         if (!(adr & 1))
  82                *(__u16 *) (map->map_priv_1 + adr) = d.x[0];
  83 }
  84
  85 /*
  86  * Fast write16 function without the probing check above
  87  */
  88 static void ixp4xx_write16(struct map_info *map, map_word d, unsigned long adr)
  89 {
  90        *(__u16 *) (map->map_priv_1 + adr) = d.x[0];
  91 }
  92
  93 struct ixp4xx_flash_info {
  94         struct mtd_info *mtd;
  95         struct map_info map;
  96         struct mtd_partition *partitions;
  97         struct resource *res;
  98 };
  99
 100 static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
 101
 102 static int ixp4xx_flash_remove(struct device *_dev)
 103 {
 104         struct platform_device *dev = to_platform_device(_dev);
 105         struct flash_platform_data *plat = dev->dev.platform_data;
 106         struct ixp4xx_flash_info *info = dev_get_drvdata(&dev->dev);
 107         map_word d;
 108
 109         dev_set_drvdata(&dev->dev, NULL);
 110
 111         if(!info)
 112                 return 0;
 113
 114         if (info->mtd) {
 115                 del_mtd_partitions(info->mtd);
 116                 map_destroy(info->mtd);
 117         }
 118         if (info->map.map_priv_1)
 119                 iounmap((void *) info->map.map_priv_1);
 120
 121         if (info->partitions)
 122                 kfree(info->partitions);
 123
 124         if (info->res) {
 125                 release_resource(info->res);
 126                 kfree(info->res);
 127         }
 128
 129         if (plat->exit)
 130                 plat->exit();
 131
 132         return 0;
 133 }
 134
 135 static int ixp4xx_flash_probe(struct device *_dev)
 136 {
 137         struct platform_device *dev = to_platform_device(_dev);
 138         struct flash_platform_data *plat = dev->dev.platform_data;
 139         struct ixp4xx_flash_info *info;
 140         int err = -1;
 141
 142         if (!plat)
 143                 return -ENODEV;
 144
 145         if (plat->init) {
 146                 err = plat->init();
 147                 if (err)
 148                         return err;
 149         }
 150
 151         info = kmalloc(sizeof(struct ixp4xx_flash_info), GFP_KERNEL);
 152         if(!info) {
 153                 err = -ENOMEM;
 154                 goto Error;
 155         }
 156         memzero(info, sizeof(struct ixp4xx_flash_info));
 157
 158         dev_set_drvdata(&dev->dev, info);
 159
 160         /*
 161          * Tell the MTD layer we're not 1:1 mapped so that it does
 162          * not attempt to do a direct access on us.
 163          */
 164         info->map.phys = NO_XIP;
 165         info->map.size = dev->resource->end - dev->resource->start + 1;
 166
 167         /*
 168          * We only support 16-bit accesses for now. If and when
 169          * any board use 8-bit access, we'll fixup the driver to
 170          * handle that.
 171          */
 172         info->map.bankwidth = 2;
 173         info->map.name = dev->dev.bus_id;
 174         info->map.read = ixp4xx_read16,
 175         info->map.write = ixp4xx_probe_write16,
 176         info->map.copy_from = ixp4xx_copy_from,
 177
 178         info->res = request_mem_region(dev->resource->start,
 179                         dev->resource->end - dev->resource->start + 1,
 180                         "IXP4XXFlash");
 181         if (!info->res) {
 182                 printk(KERN_ERR "IXP4XXFlash: Could not reserve memory region\n");
 183                 err = -ENOMEM;
 184                 goto Error;
 185         }
 186
 187         info->map.map_priv_1 = ioremap(dev->resource->start,
 188                             dev->resource->end - dev->resource->start + 1);
 189         if (!info->map.map_priv_1) {
 190                 printk(KERN_ERR "IXP4XXFlash: Failed to ioremap region\n");
 191                 err = -EIO;
 192                 goto Error;
 193         }
 194
 195         info->mtd = do_map_probe(plat->map_name, &info->map);
 196         if (!info->mtd) {
 197                 printk(KERN_ERR "IXP4XXFlash: map_probe failed\n");
 198                 err = -ENXIO;
 199                 goto Error;
 200         }
 201         info->mtd->owner = THIS_MODULE;
 202
 203         /* Use the fast version */
 204         info->map.write = ixp4xx_write16,
 205
 206         err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
 207         if (err > 0) {
 208                 err = add_mtd_partitions(info->mtd, info->partitions, err);
 209                 if(err)
 210                         printk(KERN_ERR "Could not parse partitions\n");
 211         }
 212
 213         if (err)
 214                 goto Error;
 215
 216         return 0;
 217
 218 Error:
 219         ixp4xx_flash_remove(_dev);
 220         return err;
 221 }
 222
 223 static struct device_driver ixp4xx_flash_driver = {
 224         .name           = "IXP4XX-Flash",
 225         .bus            = &platform_bus_type,
 226         .probe          = ixp4xx_flash_probe,
 227         .remove         = ixp4xx_flash_remove,
 228 };
 229
 230 static int __init ixp4xx_flash_init(void)
 231 {
 232         return driver_register(&ixp4xx_flash_driver);
 233 }
 234
 235 static void __exit ixp4xx_flash_exit(void)
 236 {
 237         driver_unregister(&ixp4xx_flash_driver);
 238 }
 239
 240
 241 module_init(ixp4xx_flash_init);
 242 module_exit(ixp4xx_flash_exit);
 243
 244 MODULE_LICENSE("GPL");
 245 MODULE_DESCRIPTION("MTD map driver for Intel IXP4xx systems");
 246 MODULE_AUTHOR("Deepak Saxena");
 247