drivers/mtd/maps/ixp2000.c

   1 /*
   2  * $Id: ixp2000.c,v 1.9 2005/11/07 11:14:27 gleixner Exp $
   3  *
   4  * drivers/mtd/maps/ixp2000.c
   5  *
   6  * Mapping for the Intel XScale IXP2000 based systems
   7  *
   8  * Copyright (C) 2002 Intel Corp.
   9  * Copyright (C) 2003-2004 MontaVista Software, Inc.
  10  *
  11  * Original Author: Naeem M Afzal <naeem.m.afzal@intel.com>
  12  * Maintainer: Deepak Saxena <dsaxena@plexity.net>
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License version 2 as
  16  * published by the Free Software Foundation.
  17  *
  18  */
  19
  20 #include <linux/module.h>
  21 #include <linux/types.h>
  22 #include <linux/init.h>
  23 #include <linux/kernel.h>
  24 #include <linux/string.h>
  25 #include <linux/slab.h>
  26 #include <linux/ioport.h>
  27 #include <linux/device.h>
  28 #include <linux/platform_device.h>
  29
  30 #include <linux/mtd/mtd.h>
  31 #include <linux/mtd/map.h>
  32 #include <linux/mtd/partitions.h>
  33
  34 #include <asm/io.h>
  35 #include <asm/hardware.h>
  36 #include <asm/mach/flash.h>
  37
  38 #include <linux/reboot.h>
  39
  40 struct ixp2000_flash_info {
  41         struct          mtd_info *mtd;
  42         struct          map_info map;
  43         struct          mtd_partition *partitions;
  44         struct          resource *res;
  45 };
  46
  47 static inline unsigned long flash_bank_setup(struct map_info *map, unsigned long ofs)
  48 {
  49         unsigned long (*set_bank)(unsigned long) =
  50                 (unsigned long(*)(unsigned long))map->map_priv_2;
  51
  52         return (set_bank ? set_bank(ofs) : ofs);
  53 }
  54
  55 #ifdef __ARMEB__
  56 /*
  57  * Rev A0 and A1 of IXP2400 silicon have a broken addressing unit which
  58  * causes the lower address bits to be XORed with 0x11 on 8 bit accesses
  59  * and XORed with 0x10 on 16 bit accesses. See the spec update, erratum 44.
  60  */
  61 static int erratum44_workaround = 0;
  62
  63 static inline unsigned long address_fix8_write(unsigned long addr)
  64 {
  65         if (erratum44_workaround) {
  66                 return (addr ^ 3);
  67         }
  68         return addr;
  69 }
  70 #else
  71
  72 #define address_fix8_write(x)   (x)
  73 #endif
  74
  75 static map_word ixp2000_flash_read8(struct map_info *map, unsigned long ofs)
  76 {
  77         map_word val;
  78
  79         val.x[0] =  *((u8 *)(map->map_priv_1 + flash_bank_setup(map, ofs)));
  80         return val;
  81 }
  82
  83 /*
  84  * We can't use the standard memcpy due to the broken SlowPort
  85  * address translation on rev A0 and A1 silicon and the fact that
  86  * we have banked flash.
  87  */
  88 static void ixp2000_flash_copy_from(struct map_info *map, void *to,
  89                               unsigned long from, ssize_t len)
  90 {
  91         from = flash_bank_setup(map, from);
  92         while(len--)
  93                 *(__u8 *) to++ = *(__u8 *)(map->map_priv_1 + from++);
  94 }
  95
  96 static void ixp2000_flash_write8(struct map_info *map, map_word d, unsigned long ofs)
  97 {
  98         *(__u8 *) (address_fix8_write(map->map_priv_1 +
  99                                       flash_bank_setup(map, ofs))) = d.x[0];
 100 }
 101
 102 static void ixp2000_flash_copy_to(struct map_info *map, unsigned long to,
 103                             const void *from, ssize_t len)
 104 {
 105         to = flash_bank_setup(map, to);
 106         while(len--) {
 107                 unsigned long tmp = address_fix8_write(map->map_priv_1 + to++);
 108                 *(__u8 *)(tmp) = *(__u8 *)(from++);
 109         }
 110 }
 111
 112
 113 static int ixp2000_flash_remove(struct platform_device *dev)
 114 {
 115         struct flash_platform_data *plat = dev->dev.platform_data;
 116         struct ixp2000_flash_info *info = platform_get_drvdata(dev);
 117
 118         platform_set_drvdata(dev, NULL);
 119
 120         if(!info)
 121                 return 0;
 122
 123         if (info->mtd) {
 124                 del_mtd_partitions(info->mtd);
 125                 map_destroy(info->mtd);
 126         }
 127         if (info->map.map_priv_1)
 128                 iounmap((void *) info->map.map_priv_1);
 129
 130         kfree(info->partitions);
 131
 132         if (info->res) {
 133                 release_resource(info->res);
 134                 kfree(info->res);
 135         }
 136
 137         if (plat->exit)
 138                 plat->exit();
 139
 140         return 0;
 141 }
 142
 143
 144 static int ixp2000_flash_probe(struct platform_device *dev)
 145 {
 146         static const char *probes[] = { "RedBoot", "cmdlinepart", NULL };
 147         struct ixp2000_flash_data *ixp_data = dev->dev.platform_data;
 148         struct flash_platform_data *plat;
 149         struct ixp2000_flash_info *info;
 150         unsigned long window_size;
 151         int err = -1;
 152
 153         if (!ixp_data)
 154                 return -ENODEV;
 155
 156         plat = ixp_data->platform_data;
 157         if (!plat)
 158                 return -ENODEV;
 159
 160         window_size = dev->resource->end - dev->resource->start + 1;
 161         dev_info(&dev->dev, "Probe of IXP2000 flash(%d banks x %dMiB)\n",
 162                  ixp_data->nr_banks, ((u32)window_size >> 20));
 163
 164         if (plat->width != 1) {
 165                 dev_err(&dev->dev, "IXP2000 MTD map only supports 8-bit mode, asking for %d\n",
 166                         plat->width * 8);
 167                 return -EIO;
 168         }
 169
 170         info = kmalloc(sizeof(struct ixp2000_flash_info), GFP_KERNEL);
 171         if(!info) {
 172                 err = -ENOMEM;
 173                 goto Error;
 174         }
 175         memzero(info, sizeof(struct ixp2000_flash_info));
 176
 177         platform_set_drvdata(dev, info);
 178
 179         /*
 180          * Tell the MTD layer we're not 1:1 mapped so that it does
 181          * not attempt to do a direct access on us.
 182          */
 183         info->map.phys = NO_XIP;
 184
 185         info->map.size = ixp_data->nr_banks * window_size;
 186         info->map.bankwidth = 1;
 187
 188         /*
 189          * map_priv_2 is used to store a ptr to to the bank_setup routine
 190          */
 191         info->map.map_priv_2 = (unsigned long) ixp_data->bank_setup;
 192
 193         info->map.name = dev->dev.bus_id;
 194         info->map.read = ixp2000_flash_read8;
 195         info->map.write = ixp2000_flash_write8;
 196         info->map.copy_from = ixp2000_flash_copy_from;
 197         info->map.copy_to = ixp2000_flash_copy_to;
 198
 199         info->res = request_mem_region(dev->resource->start,
 200                         dev->resource->end - dev->resource->start + 1,
 201                         dev->dev.bus_id);
 202         if (!info->res) {
 203                 dev_err(&dev->dev, "Could not reserve memory region\n");
 204                 err = -ENOMEM;
 205                 goto Error;
 206         }
 207
 208         info->map.map_priv_1 = (unsigned long) ioremap(dev->resource->start,
 209                                 dev->resource->end - dev->resource->start + 1);
 210         if (!info->map.map_priv_1) {
 211                 dev_err(&dev->dev, "Failed to ioremap flash region\n");
 212                 err = -EIO;
 213                 goto Error;
 214         }
 215
 216 #if defined(__ARMEB__)
 217         /*
 218          * Enable erratum 44 workaround for NPUs with broken slowport
 219          */
 220
 221         erratum44_workaround = ixp2000_has_broken_slowport();
 222         dev_info(&dev->dev, "Erratum 44 workaround %s\n",
 223                erratum44_workaround ? "enabled" : "disabled");
 224 #endif
 225
 226         info->mtd = do_map_probe(plat->map_name, &info->map);
 227         if (!info->mtd) {
 228                 dev_err(&dev->dev, "map_probe failed\n");
 229                 err = -ENXIO;
 230                 goto Error;
 231         }
 232         info->mtd->owner = THIS_MODULE;
 233
 234         err = parse_mtd_partitions(info->mtd, probes, &info->partitions, 0);
 235         if (err > 0) {
 236                 err = add_mtd_partitions(info->mtd, info->partitions, err);
 237                 if(err)
 238                         dev_err(&dev->dev, "Could not parse partitions\n");
 239         }
 240
 241         if (err)
 242                 goto Error;
 243
 244         return 0;
 245
 246 Error:
 247         ixp2000_flash_remove(dev);
 248         return err;
 249 }
 250
 251 static struct platform_driver ixp2000_flash_driver = {
 252         .probe          = ixp2000_flash_probe,
 253         .remove         = ixp2000_flash_remove,
 254         .driver         = {
 255                 .name   = "IXP2000-Flash",
 256         },
 257 };
 258
 259 static int __init ixp2000_flash_init(void)
 260 {
 261         return platform_driver_register(&ixp2000_flash_driver);
 262 }
 263
 264 static void __exit ixp2000_flash_exit(void)
 265 {
 266         platform_driver_unregister(&ixp2000_flash_driver);
 267 }
 268
 269 module_init(ixp2000_flash_init);
 270 module_exit(ixp2000_flash_exit);
 271 MODULE_LICENSE("GPL");
 272 MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
 273