drivers/mtd/maps/shark_pmap_of.c

   1 /*
   2  * Flash mappings described by the OF (or flattened) device tree
   3  *
   4  * Copyright (C) 2006 MontaVista Software Inc.
   5  * Author: Vitaly Wool <vwool@ru.mvista.com>
   6  *
   7  * Revised to handle newer style flash binding by:
   8  *   Copyright (C) 2007 David Gibson, IBM Corporation.
   9  *
  10  * This program is free software; you can redistribute  it and/or modify it
  11  * under  the terms of  the GNU General  Public License as published by the
  12  * Free Software Foundation;  either version 2 of the  License, or (at your
  13  * option) any later version.
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/types.h>
  18 #include <linux/init.h>
  19 #include <linux/device.h>
  20 #include <linux/mtd/mtd.h>
  21 #include <linux/mtd/map.h>
  22 #include <linux/mtd/xip.h>
  23 #include <linux/mtd/partitions.h>
  24 #include <linux/of.h>
  25 #include <linux/of_platform.h>
  26 #include <linux/slab.h>
  27
  28 struct of_flash {
  29         struct mtd_info         *mtd;
  30         struct map_info         map;
  31         struct resource         *res;
  32 #ifdef CONFIG_MTD_PARTITIONS
  33         struct mtd_partition    *parts;
  34 #endif
  35 };
  36
  37 // Support for MPC5200 bank select on Shark board, map_priv_1 - MBAR address
  38 void of_shark_mpc5200_set_bank(unsigned long map_priv_1, unsigned long addr)
  39 {
  40         unsigned long cfg;
  41         volatile int i;
  42
  43         cfg = (*(unsigned long *)(map_priv_1 + 0x0300)) & ~0xC0;
  44         cfg = cfg | ( ( (addr >> 25) & 3) << 6);
  45
  46         //debug("A:%x:%x ", addr, cfg);
  47         *(unsigned long *)(map_priv_1 + 0x0300) = cfg;
  48         i = 5; // some small delay
  49 }
  50
  51 static map_word __xipram of_shark_map_read(struct map_info *map, unsigned long ofs)
  52 {
  53         of_shark_mpc5200_set_bank(map->map_priv_1, ofs);
  54         return inline_map_read(map, ofs);
  55 }
  56
  57 static void __xipram of_shark_map_write(struct map_info *map, const map_word datum, unsigned long ofs)
  58 {
  59         of_shark_mpc5200_set_bank(map->map_priv_1, ofs);
  60         inline_map_write(map, datum, ofs);
  61 }
  62
  63 static void __xipram of_shark_map_copy_from(struct map_info *map, void *to, unsigned long from, ssize_t len)
  64 {
  65         if (map->cached)
  66                 memcpy(to, (char *)map->cached + from, len);
  67         else
  68         {
  69                 of_shark_mpc5200_set_bank(map->map_priv_1, from);
  70                 if( ((int)from < 0x2000000) && ((int)from + len > 0x2000000) )
  71                 {
  72                         int iFirstBankLength = 0x2000000 - (int)from;
  73
  74                         memcpy_fromio(to, map->virt + from, iFirstBankLength);
  75
  76                         of_shark_mpc5200_set_bank(map->map_priv_1, from + iFirstBankLength);
  77                         memcpy_fromio(to + iFirstBankLength, map->virt + from + iFirstBankLength, len - iFirstBankLength);
  78                 }
  79                 else
  80                         memcpy_fromio(to, map->virt + from, len);
  81         }
  82 }
  83
  84 static void __xipram of_shark_map_copy_to(struct map_info *map, unsigned long to, const void *from, ssize_t len)
  85 {
  86         of_shark_mpc5200_set_bank(map->map_priv_1, (unsigned long)from);
  87         if( ((int)from < 0x2000000) && ((int)from + len > 0x2000000) )
  88         {
  89                 int iFirstBankLength = 0x2000000 - (int)from;
  90                 memcpy_toio(map->virt + to, from, iFirstBankLength);
  91
  92                 of_shark_mpc5200_set_bank(map->map_priv_1, (unsigned long)from + iFirstBankLength);
  93                 memcpy_toio(map->virt + to + iFirstBankLength, from + iFirstBankLength, len - iFirstBankLength);
  94         }
  95         else
  96                 memcpy_toio(map->virt + to, from, len);
  97 }
  98
  99 #ifdef CONFIG_MTD_PARTITIONS
 100 #define OF_FLASH_PARTS(info)    ((info)->parts)
 101
 102 static int parse_obsolete_partitions(struct platform_device *dev,
 103                                      struct of_flash *info,
 104                                      struct device_node *dp)
 105 {
 106         int i, plen, nr_parts;
 107         const struct {
 108                 u32 offset, len;
 109         } *part;
 110         const char *names;
 111
 112         part = of_get_property(dp, "partitions", &plen);
 113         if (!part)
 114                 return 0; /* No partitions found */
 115
 116         dev_warn(&dev->dev, "Device tree uses obsolete partition map binding\n");
 117
 118         nr_parts = plen / sizeof(part[0]);
 119
 120         info->parts = kzalloc(nr_parts * sizeof(*info->parts), GFP_KERNEL);
 121         if (!info->parts)
 122                 return -ENOMEM;
 123
 124         names = of_get_property(dp, "partition-names", &plen);
 125
 126         for (i = 0; i < nr_parts; i++) {
 127                 info->parts[i].offset = part->offset;
 128                 info->parts[i].size   = part->len & ~1;
 129                 if (part->len & 1) /* bit 0 set signifies read only partition */
 130                         info->parts[i].mask_flags = MTD_WRITEABLE;
 131
 132                 if (names && (plen > 0)) {
 133                         int len = strlen(names) + 1;
 134
 135                         info->parts[i].name = (char *)names;
 136                         plen -= len;
 137                         names += len;
 138                 } else {
 139                         info->parts[i].name = "unnamed";
 140                 }
 141
 142                 part++;
 143         }
 144
 145         return nr_parts;
 146 }
 147 #else /* MTD_PARTITIONS */
 148 #define OF_FLASH_PARTS(info)            (0)
 149 #define parse_partitions(info, dev)     (0)
 150 #endif /* MTD_PARTITIONS */
 151
 152 static int of_shark_flash_remove(struct platform_device *dev)
 153 {
 154         struct of_flash *info;
 155
 156         info = dev_get_drvdata(&dev->dev);
 157         if (!info)
 158                 return 0;
 159         dev_set_drvdata(&dev->dev, NULL);
 160
 161         if (info->mtd) {
 162                 if (OF_FLASH_PARTS(info)) {
 163                         del_mtd_partitions(info->mtd);
 164                         kfree(OF_FLASH_PARTS(info));
 165                 } else {
 166                         del_mtd_device(info->mtd);
 167                 }
 168                 map_destroy(info->mtd);
 169         }
 170
 171         if (info->map.map_priv_1)
 172                 iounmap((void*)info->map.map_priv_1);
 173
 174         if (info->map.virt)
 175                 iounmap(info->map.virt);
 176
 177         if (info->res) {
 178                 release_resource(info->res);
 179                 kfree(info->res);
 180         }
 181
 182         return 0;
 183 }
 184
 185 /* Helper function to handle probing of the obsolete "direct-mapped"
 186  * compatible binding, which has an extra "probe-type" property
 187  * describing the type of flash probe necessary. */
 188 static struct mtd_info * __devinit obsolete_probe(struct platform_device *dev,
 189                                                   struct map_info *map)
 190 {
 191         struct device_node *dp = dev->dev.of_node;
 192         const char *of_probe;
 193         struct mtd_info *mtd;
 194         static const char *rom_probe_types[]
 195                 = { "cfi_probe", "jedec_probe", "map_rom"};
 196         int i;
 197
 198         dev_warn(&dev->dev, "Device tree uses obsolete \"direct-mapped\" "
 199                  "flash binding\n");
 200
 201         of_probe = of_get_property(dp, "probe-type", NULL);
 202         if (!of_probe) {
 203                 for (i = 0; i < ARRAY_SIZE(rom_probe_types); i++) {
 204                         mtd = do_map_probe(rom_probe_types[i], map);
 205                         if (mtd)
 206                                 return mtd;
 207                 }
 208                 return NULL;
 209         } else if (strcmp(of_probe, "CFI") == 0) {
 210                 return do_map_probe("cfi_probe", map);
 211         } else if (strcmp(of_probe, "JEDEC") == 0) {
 212                 return do_map_probe("jedec_probe", map);
 213         } else {
 214                 if (strcmp(of_probe, "ROM") != 0)
 215                         dev_warn(&dev->dev, "obsolete_probe: don't know probe "
 216                                  "type '%s', mapping as rom\n", of_probe);
 217                 return do_map_probe("mtd_rom", map);
 218         }
 219 }
 220
 221 static int __devinit of_shark_flash_probe(struct platform_device *dev,
 222                                     const struct of_device_id *match)
 223 {
 224 #ifdef CONFIG_MTD_PARTITIONS
 225         static const char *part_probe_types[]
 226                 = { "cmdlinepart", "RedBoot", NULL };
 227 #endif
 228         struct device_node *dp = dev->dev.of_node;
 229         struct device_node *np_sys;
 230         struct resource res;
 231         struct of_flash *info;
 232         const char *probe_type = match->data;
 233         const u32 *width;
 234         int err;
 235
 236         const struct of_device_id immr_ids[] = {
 237                 { .compatible = "fsl,mpc5200-immr", },
 238                 { .compatible = "fsl,mpc5200b-immr", },
 239                 { .type = "soc", .compatible = "mpc5200", }, /* lite5200 */
 240                 { .type = "builtin", .compatible = "mpc5200", }, /* efika */
 241                 {}
 242         };
 243
 244         err = -ENXIO;
 245         if (of_address_to_resource(dp, 0, &res)) {
 246                 dev_err(&dev->dev, "Can't get IO address from device tree\n");
 247                 goto err_out;
 248         }
 249
 250         dev_dbg(&dev->dev, "of_flash device: %.8llx-%.8llx\n",
 251                 (unsigned long long)res.start, (unsigned long long)res.end);
 252
 253         err = -ENOMEM;
 254         info = kzalloc(sizeof(*info), GFP_KERNEL);
 255         if (!info)
 256                 goto err_out;
 257
 258         dev_set_drvdata(&dev->dev, info);
 259
 260         err = -EBUSY;
 261         info->res = request_mem_region(res.start, res.end - res.start + 1,
 262                                        dev_name(&dev->dev));
 263         if (!info->res)
 264                 goto err_out;
 265
 266         err = -ENXIO;
 267         width = of_get_property(dp, "bank-width", NULL);
 268         if (!width) {
 269                 dev_err(&dev->dev, "Can't get bank width from device tree\n");
 270                 goto err_out;
 271         }
 272
 273         info->map.name = dev_name(&dev->dev);
 274         info->map.phys = res.start;
 275         info->map.size = res.end - res.start + 1;
 276         info->map.bankwidth = *width;
 277
 278         err = -ENOMEM;
 279         info->map.virt = ioremap(info->map.phys, info->map.size);
 280         if (!info->map.virt) {
 281                 dev_err(&dev->dev, "Failed to ioremap() flash region\n");
 282                 goto err_out;
 283         }
 284
 285         info->map.read = of_shark_map_read;
 286         info->map.write = of_shark_map_write;
 287         info->map.copy_from = of_shark_map_copy_from;
 288         info->map.copy_to = of_shark_map_copy_to;
 289
 290         /* map the whole register space */
 291         np_sys = of_find_matching_node(NULL, immr_ids);
 292         info->map.map_priv_1 = (unsigned long)of_iomap(np_sys, 0);
 293         if (!info->map.map_priv_1) {
 294                 dev_err(&dev->dev, "of_shark_flash_probe: could not get MBAR address\n");
 295                 goto err_out;
 296         }
 297
 298         if (probe_type)
 299                 info->mtd = do_map_probe(probe_type, &info->map);
 300         else
 301                 info->mtd = obsolete_probe(dev, &info->map);
 302
 303         err = -ENXIO;
 304         if (!info->mtd) {
 305                 dev_err(&dev->dev, "do_map_probe() failed\n");
 306                 goto err_out;
 307         }
 308         info->mtd->owner = THIS_MODULE;
 309         info->mtd->dev.parent = &dev->dev;
 310
 311 #ifdef CONFIG_MTD_PARTITIONS
 312         /* First look for RedBoot table or partitions on the command
 313          * line, these take precedence over device tree information */
 314         err = parse_mtd_partitions(info->mtd, part_probe_types,
 315                                    &info->parts, 0);
 316         if (err < 0)
 317                 return err;
 318
 319 #ifdef CONFIG_MTD_OF_PARTS
 320         if (err == 0) {
 321                 err = of_mtd_parse_partitions(&dev->dev, dp, &info->parts);
 322                 if (err < 0)
 323                         return err;
 324         }
 325 #endif
 326
 327         if (err == 0) {
 328                 err = parse_obsolete_partitions(dev, info, dp);
 329                 if (err < 0)
 330                         return err;
 331         }
 332
 333         if (err > 0)
 334                 add_mtd_partitions(info->mtd, info->parts, err);
 335         else
 336 #endif
 337                 add_mtd_device(info->mtd);
 338
 339         return 0;
 340
 341 err_out:
 342         of_shark_flash_remove(dev);
 343         return err;
 344 }
 345
 346 static struct of_device_id of_shark_flash_match[] = {
 347         {
 348                 .compatible     = "cfi-flash",
 349                 .data           = (void *)"cfi_probe",
 350         },
 351         {
 352                 /* FIXME: JEDEC chips can't be safely and reliably
 353                  * probed, although the mtd code gets it right in
 354                  * practice most of the time.  We should use the
 355                  * vendor and device ids specified by the binding to
 356                  * bypass the heuristic probe code, but the mtd layer
 357                  * provides, at present, no interface for doing so
 358                  * :(. */
 359                 .compatible     = "jedec-flash",
 360                 .data           = (void *)"jedec_probe",
 361         },
 362         {
 363                 .type           = "rom",
 364                 .compatible     = "direct-mapped"
 365         },
 366         { },
 367 };
 368 MODULE_DEVICE_TABLE(of, of_flash_match);
 369
 370 static struct of_platform_driver of_shark_flash_driver = {
 371         .driver         = {
 372                 .name           = "of-flash",
 373                 .owner          = THIS_MODULE,
 374                 .of_match_table = of_shark_flash_match,
 375
 376         },
 377         .probe          = of_shark_flash_probe,
 378         .remove         = of_shark_flash_remove,
 379 };
 380
 381 static int __init of_shark_flash_init(void)
 382 {
 383         return of_register_platform_driver(&of_shark_flash_driver);
 384 }
 385
 386 static void __exit of_shark_flash_exit(void)
 387 {
 388         of_unregister_platform_driver(&of_shark_flash_driver);
 389 }
 390
 391 module_init(of_shark_flash_init);
 392 module_exit(of_shark_flash_exit);
 393
 394 MODULE_LICENSE("GPL");
 395 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
 396 MODULE_DESCRIPTION("Device tree based MTD map driver");