drivers/mtd/maps/ixp4xx.c

   1 /*
   2  * $Id: ixp4xx.c,v 1.12 2005/11/07 11:14:27 gleixner 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] = le16_to_cpu(readw(map->virt + 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         void __iomem *src = map->virt + from;
  63         u16 data;
  64
  65         for (i = 0; i < (len / 2); i++) {
  66                 data = le16_to_cpu(readw(src + 2*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(le16_to_cpu(readw(src + 2*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                 writew(cpu_to_le16(d.x[0]), map->virt + adr);
  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         writew(cpu_to_le16(d.x[0]), map->virt + adr);
  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 platform_device *dev)
 103 {
 104         struct flash_platform_data *plat = dev->dev.platform_data;
 105         struct ixp4xx_flash_info *info = platform_get_drvdata(dev);
 106
 107         platform_set_drvdata(dev, NULL);
 108
 109         if(!info)
 110                 return 0;
 111
 112         if (info->mtd) {
 113                 del_mtd_partitions(info->mtd);
 114                 map_destroy(info->mtd);
 115         }
 116         if (info->map.virt)
 117                 iounmap(info->map.virt);
 118
 119         kfree(info->partitions);
 120
 121         if (info->res) {
 122                 release_resource(info->res);
 123                 kfree(info->res);
 124         }
 125
 126         if (plat->exit)
 127                 plat->exit();
 128
 129         return 0;
 130 }
 131
 132 static int ixp4xx_flash_probe(struct platform_device *dev)
 133 {
 134         struct flash_platform_data *plat = dev->dev.platform_data;
 135         struct ixp4xx_flash_info *info;
 136         int err = -1;
 137
 138         if (!plat)
 139                 return -ENODEV;
 140
 141         if (plat->init) {
 142                 err = plat->init();
 143                 if (err)
 144                         return err;
 145         }
 146
 147         info = kmalloc(sizeof(struct ixp4xx_flash_info), GFP_KERNEL);
 148         if(!info) {
 149                 err = -ENOMEM;
 150                 goto Error;
 151         }
 152         memzero(info, sizeof(struct ixp4xx_flash_info));
 153
 154         platform_set_drvdata(dev, info);
 155
 156         /*
 157          * Tell the MTD layer we're not 1:1 mapped so that it does
 158          * not attempt to do a direct access on us.
 159          */
 160         info->map.phys = NO_XIP;
 161         info->map.size = dev->resource->end - dev->resource->start + 1;
 162
 163         /*
 164          * We only support 16-bit accesses for now. If and when
 165          * any board use 8-bit access, we'll fixup the driver to
 166          * handle that.
 167          */
 168         info->map.bankwidth = 2;
 169         info->map.name = dev->dev.bus_id;
 170         info->map.read = ixp4xx_read16,
 171         info->map.write = ixp4xx_probe_write16,
 172         info->map.copy_from = ixp4xx_copy_from,
 173
 174         info->res = request_mem_region(dev->resource->start,
 175                         dev->resource->end - dev->resource->start + 1,
 176                         "IXP4XXFlash");
 177         if (!info->res) {
 178                 printk(KERN_ERR "IXP4XXFlash: Could not reserve memory region\n");
 179                 err = -ENOMEM;
 180                 goto Error;
 181         }
 182
 183         info->map.virt = ioremap(dev->resource->start,
 184                                  dev->resource->end - dev->resource->start + 1);
 185         if (!info->map.virt) {
 186                 printk(KERN_ERR "IXP4XXFlash: Failed to ioremap region\n");
 187                 err = -EIO;
 188                 goto Error;
 189         }
 190
 191         info->mtd = do_map_probe(plat->map_name, &info->map);
 192         if (!info->mtd) {
 193                 printk(KERN_ERR "IXP4XXFlash: map_probe failed\n");
 194                 err = -ENXIO;
 195                 goto Error;
 196         }
 197         info->mtd->owner = THIS_MODULE;
 198
 199         /* Use the fast version */
 200         info->map.write = ixp4xx_write16,
 201
 202         err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
 203         if (err > 0) {
 204                 err = add_mtd_partitions(info->mtd, info->partitions, err);
 205                 if(err)
 206                         printk(KERN_ERR "Could not parse partitions\n");
 207         }
 208
 209         if (err)
 210                 goto Error;
 211
 212         return 0;
 213
 214 Error:
 215         ixp4xx_flash_remove(dev);
 216         return err;
 217 }
 218
 219 static struct platform_driver ixp4xx_flash_driver = {
 220         .probe          = ixp4xx_flash_probe,
 221         .remove         = ixp4xx_flash_remove,
 222         .driver         = {
 223                 .name   = "IXP4XX-Flash",
 224         },
 225 };
 226
 227 static int __init ixp4xx_flash_init(void)
 228 {
 229         return platform_driver_register(&ixp4xx_flash_driver);
 230 }
 231
 232 static void __exit ixp4xx_flash_exit(void)
 233 {
 234         platform_driver_unregister(&ixp4xx_flash_driver);
 235 }
 236
 237
 238 module_init(ixp4xx_flash_init);
 239 module_exit(ixp4xx_flash_exit);
 240
 241 MODULE_LICENSE("GPL");
 242 MODULE_DESCRIPTION("MTD map driver for Intel IXP4xx systems");
 243 MODULE_AUTHOR("Deepak Saxena");