drivers/mtd/maps/physmap-core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Normal mappings of chips in physical memory
   4  *
   5  * Copyright (C) 2003 MontaVista Software Inc.
   6  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
   7  *
   8  * 031022 - [jsun] add run-time configure and partition setup
   9  *
  10  * Device tree support:
  11  *    Copyright (C) 2006 MontaVista Software Inc.
  12  *    Author: Vitaly Wool <vwool@ru.mvista.com>
  13  *
  14  *    Revised to handle newer style flash binding by:
  15  *    Copyright (C) 2007 David Gibson, IBM Corporation.
  16  *
  17  * GPIO address extension:
  18  *    Handle the case where a flash device is mostly addressed using physical
  19  *    line and supplemented by GPIOs.  This way you can hook up say a 8MiB flash
  20  *    to a 2MiB memory range and use the GPIOs to select a particular range.
  21  *
  22  *    Copyright © 2000 Nicolas Pitre <nico@cam.org>
  23  *    Copyright © 2005-2009 Analog Devices Inc.
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/types.h>
  28 #include <linux/kernel.h>
  29 #include <linux/init.h>
  30 #include <linux/slab.h>
  31 #include <linux/device.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/mtd/mtd.h>
  34 #include <linux/mtd/map.h>
  35 #include <linux/mtd/partitions.h>
  36 #include <linux/mtd/physmap.h>
  37 #include <linux/mtd/concat.h>
  38 #include <linux/mtd/cfi_endian.h>
  39 #include <linux/io.h>
  40 #include <linux/of_device.h>
  41 #include <linux/pm_runtime.h>
  42 #include <linux/gpio/consumer.h>
  43
  44 #include "physmap-gemini.h"
  45 #include "physmap-ixp4xx.h"
  46 #include "physmap-versatile.h"
  47
  48 struct physmap_flash_info {
  49         unsigned int            nmaps;
  50         struct mtd_info         **mtds;
  51         struct mtd_info         *cmtd;
  52         struct map_info         *maps;
  53         spinlock_t              vpp_lock;
  54         int                     vpp_refcnt;
  55         const char              *probe_type;
  56         const char * const      *part_types;
  57         unsigned int            nparts;
  58         const struct mtd_partition *parts;
  59         struct gpio_descs       *gpios;
  60         unsigned int            gpio_values;
  61         unsigned int            win_order;
  62 };
  63
  64 static int physmap_flash_remove(struct platform_device *dev)
  65 {
  66         struct physmap_flash_info *info;
  67         struct physmap_flash_data *physmap_data;
  68         int i, err = 0;
  69
  70         info = platform_get_drvdata(dev);
  71         if (!info)
  72                 goto out;
  73
  74         if (info->cmtd) {
  75                 err = mtd_device_unregister(info->cmtd);
  76                 if (err)
  77                         goto out;
  78
  79                 if (info->cmtd != info->mtds[0])
  80                         mtd_concat_destroy(info->cmtd);
  81         }
  82
  83         for (i = 0; i < info->nmaps; i++) {
  84                 if (info->mtds[i])
  85                         map_destroy(info->mtds[i]);
  86         }
  87
  88         physmap_data = dev_get_platdata(&dev->dev);
  89         if (physmap_data && physmap_data->exit)
  90                 physmap_data->exit(dev);
  91
  92 out:
  93         pm_runtime_put(&dev->dev);
  94         pm_runtime_disable(&dev->dev);
  95         return err;
  96 }
  97
  98 static void physmap_set_vpp(struct map_info *map, int state)
  99 {
 100         struct platform_device *pdev;
 101         struct physmap_flash_data *physmap_data;
 102         struct physmap_flash_info *info;
 103         unsigned long flags;
 104
 105         pdev = (struct platform_device *)map->map_priv_1;
 106         physmap_data = dev_get_platdata(&pdev->dev);
 107
 108         if (!physmap_data->set_vpp)
 109                 return;
 110
 111         info = platform_get_drvdata(pdev);
 112
 113         spin_lock_irqsave(&info->vpp_lock, flags);
 114         if (state) {
 115                 if (++info->vpp_refcnt == 1)    /* first nested 'on' */
 116                         physmap_data->set_vpp(pdev, 1);
 117         } else {
 118                 if (--info->vpp_refcnt == 0)    /* last nested 'off' */
 119                         physmap_data->set_vpp(pdev, 0);
 120         }
 121         spin_unlock_irqrestore(&info->vpp_lock, flags);
 122 }
 123
 124 #if IS_ENABLED(CONFIG_MTD_PHYSMAP_GPIO_ADDR)
 125 static void physmap_set_addr_gpios(struct physmap_flash_info *info,
 126                                    unsigned long ofs)
 127 {
 128         unsigned int i;
 129
 130         ofs >>= info->win_order;
 131         if (info->gpio_values == ofs)
 132                 return;
 133
 134         for (i = 0; i < info->gpios->ndescs; i++) {
 135                 if ((BIT(i) & ofs) == (BIT(i) & info->gpio_values))
 136                         continue;
 137
 138                 gpiod_set_value(info->gpios->desc[i], !!(BIT(i) & ofs));
 139         }
 140
 141         info->gpio_values = ofs;
 142 }
 143
 144 #define win_mask(order)         (BIT(order) - 1)
 145
 146 static map_word physmap_addr_gpios_read(struct map_info *map,
 147                                         unsigned long ofs)
 148 {
 149         struct platform_device *pdev;
 150         struct physmap_flash_info *info;
 151         map_word mw;
 152         u16 word;
 153
 154         pdev = (struct platform_device *)map->map_priv_1;
 155         info = platform_get_drvdata(pdev);
 156         physmap_set_addr_gpios(info, ofs);
 157
 158         word = readw(map->virt + (ofs & win_mask(info->win_order)));
 159         mw.x[0] = word;
 160         return mw;
 161 }
 162
 163 static void physmap_addr_gpios_copy_from(struct map_info *map, void *buf,
 164                                          unsigned long ofs, ssize_t len)
 165 {
 166         struct platform_device *pdev;
 167         struct physmap_flash_info *info;
 168
 169         pdev = (struct platform_device *)map->map_priv_1;
 170         info = platform_get_drvdata(pdev);
 171
 172         while (len) {
 173                 unsigned int winofs = ofs & win_mask(info->win_order);
 174                 unsigned int chunklen = min_t(unsigned int, len,
 175                                               BIT(info->win_order) - winofs);
 176
 177                 physmap_set_addr_gpios(info, ofs);
 178                 memcpy_fromio(buf, map->virt + winofs, chunklen);
 179                 len -= chunklen;
 180                 buf += chunklen;
 181                 ofs += chunklen;
 182         }
 183 }
 184
 185 static void physmap_addr_gpios_write(struct map_info *map, map_word mw,
 186                                      unsigned long ofs)
 187 {
 188         struct platform_device *pdev;
 189         struct physmap_flash_info *info;
 190         u16 word;
 191
 192         pdev = (struct platform_device *)map->map_priv_1;
 193         info = platform_get_drvdata(pdev);
 194         physmap_set_addr_gpios(info, ofs);
 195
 196         word = mw.x[0];
 197         writew(word, map->virt + (ofs & win_mask(info->win_order)));
 198 }
 199
 200 static void physmap_addr_gpios_copy_to(struct map_info *map, unsigned long ofs,
 201                                        const void *buf, ssize_t len)
 202 {
 203         struct platform_device *pdev;
 204         struct physmap_flash_info *info;
 205
 206         pdev = (struct platform_device *)map->map_priv_1;
 207         info = platform_get_drvdata(pdev);
 208
 209         while (len) {
 210                 unsigned int winofs = ofs & win_mask(info->win_order);
 211                 unsigned int chunklen = min_t(unsigned int, len,
 212                                               BIT(info->win_order) - winofs);
 213
 214                 physmap_set_addr_gpios(info, ofs);
 215                 memcpy_toio(map->virt + winofs, buf, chunklen);
 216                 len -= chunklen;
 217                 buf += chunklen;
 218                 ofs += chunklen;
 219         }
 220 }
 221
 222 static int physmap_addr_gpios_map_init(struct map_info *map)
 223 {
 224         map->phys = NO_XIP;
 225         map->read = physmap_addr_gpios_read;
 226         map->copy_from = physmap_addr_gpios_copy_from;
 227         map->write = physmap_addr_gpios_write;
 228         map->copy_to = physmap_addr_gpios_copy_to;
 229
 230         return 0;
 231 }
 232 #else
 233 static int physmap_addr_gpios_map_init(struct map_info *map)
 234 {
 235         return -ENOTSUPP;
 236 }
 237 #endif
 238
 239 #if IS_ENABLED(CONFIG_MTD_PHYSMAP_OF)
 240 static const struct of_device_id of_flash_match[] = {
 241         {
 242                 .compatible = "cfi-flash",
 243                 .data = "cfi_probe",
 244         },
 245         {
 246                 /*
 247                  * FIXME: JEDEC chips can't be safely and reliably
 248                  * probed, although the mtd code gets it right in
 249                  * practice most of the time.  We should use the
 250                  * vendor and device ids specified by the binding to
 251                  * bypass the heuristic probe code, but the mtd layer
 252                  * provides, at present, no interface for doing so
 253                  * :(.
 254                  */
 255                 .compatible = "jedec-flash",
 256                 .data = "jedec_probe",
 257         },
 258         {
 259                 .compatible = "mtd-ram",
 260                 .data = "map_ram",
 261         },
 262         {
 263                 .compatible = "mtd-rom",
 264                 .data = "map_rom",
 265         },
 266         {
 267                 .type = "rom",
 268                 .compatible = "direct-mapped"
 269         },
 270         { /* sentinel */ },
 271 };
 272 MODULE_DEVICE_TABLE(of, of_flash_match);
 273
 274 static const char * const of_default_part_probes[] = {
 275         "cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL
 276 };
 277
 278 static const char * const *of_get_part_probes(struct platform_device *dev)
 279 {
 280         struct device_node *dp = dev->dev.of_node;
 281         const char **res;
 282         int count;
 283
 284         count = of_property_count_strings(dp, "linux,part-probe");
 285         if (count < 0)
 286                 return of_default_part_probes;
 287
 288         res = devm_kcalloc(&dev->dev, count + 1, sizeof(*res), GFP_KERNEL);
 289         if (!res)
 290                 return NULL;
 291
 292         count = of_property_read_string_array(dp, "linux,part-probe", res,
 293                                               count);
 294         if (count < 0)
 295                 return NULL;
 296
 297         return res;
 298 }
 299
 300 static const char *of_select_probe_type(struct platform_device *dev)
 301 {
 302         struct device_node *dp = dev->dev.of_node;
 303         const struct of_device_id *match;
 304         const char *probe_type;
 305
 306         match = of_match_device(of_flash_match, &dev->dev);
 307         probe_type = match->data;
 308         if (probe_type)
 309                 return probe_type;
 310
 311         dev_warn(&dev->dev,
 312                  "Device tree uses obsolete \"direct-mapped\" flash binding\n");
 313
 314         of_property_read_string(dp, "probe-type", &probe_type);
 315         if (!probe_type)
 316                 return NULL;
 317
 318         if (!strcmp(probe_type, "CFI")) {
 319                 probe_type = "cfi_probe";
 320         } else if (!strcmp(probe_type, "JEDEC")) {
 321                 probe_type = "jedec_probe";
 322         } else if (!strcmp(probe_type, "ROM")) {
 323                 probe_type = "map_rom";
 324         } else {
 325                 dev_warn(&dev->dev,
 326                          "obsolete_probe: don't know probe type '%s', mapping as rom\n",
 327                          probe_type);
 328                 probe_type = "map_rom";
 329         }
 330
 331         return probe_type;
 332 }
 333
 334 static int physmap_flash_of_init(struct platform_device *dev)
 335 {
 336         struct physmap_flash_info *info = platform_get_drvdata(dev);
 337         struct device_node *dp = dev->dev.of_node;
 338         const char *mtd_name = NULL;
 339         int err, swap = 0;
 340         bool map_indirect;
 341         unsigned int i;
 342         u32 bankwidth;
 343
 344         if (!dp)
 345                 return -EINVAL;
 346
 347         info->probe_type = of_select_probe_type(dev);
 348
 349         info->part_types = of_get_part_probes(dev);
 350         if (!info->part_types)
 351                 return -ENOMEM;
 352
 353         of_property_read_string(dp, "linux,mtd-name", &mtd_name);
 354
 355         map_indirect = of_property_read_bool(dp, "no-unaligned-direct-access");
 356
 357         err = of_property_read_u32(dp, "bank-width", &bankwidth);
 358         if (err) {
 359                 dev_err(&dev->dev, "Can't get bank width from device tree\n");
 360                 return err;
 361         }
 362
 363         if (of_property_read_bool(dp, "big-endian"))
 364                 swap = CFI_BIG_ENDIAN;
 365         else if (of_property_read_bool(dp, "little-endian"))
 366                 swap = CFI_LITTLE_ENDIAN;
 367
 368         for (i = 0; i < info->nmaps; i++) {
 369                 info->maps[i].name = mtd_name;
 370                 info->maps[i].swap = swap;
 371                 info->maps[i].bankwidth = bankwidth;
 372                 info->maps[i].device_node = dp;
 373
 374                 err = of_flash_probe_gemini(dev, dp, &info->maps[i]);
 375                 if (err)
 376                         return err;
 377
 378                 err = of_flash_probe_ixp4xx(dev, dp, &info->maps[i]);
 379                 if (err)
 380                         return err;
 381
 382                 err = of_flash_probe_versatile(dev, dp, &info->maps[i]);
 383                 if (err)
 384                         return err;
 385
 386                 /*
 387                  * On some platforms (e.g. MPC5200) a direct 1:1 mapping
 388                  * may cause problems with JFFS2 usage, as the local bus (LPB)
 389                  * doesn't support unaligned accesses as implemented in the
 390                  * JFFS2 code via memcpy(). By setting NO_XIP, the
 391                  * flash will not be exposed directly to the MTD users
 392                  * (e.g. JFFS2) any more.
 393                  */
 394                 if (map_indirect)
 395                         info->maps[i].phys = NO_XIP;
 396         }
 397
 398         return 0;
 399 }
 400 #else /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
 401 #define of_flash_match NULL
 402
 403 static int physmap_flash_of_init(struct platform_device *dev)
 404 {
 405         return -ENOTSUPP;
 406 }
 407 #endif /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
 408
 409 static const char * const rom_probe_types[] = {
 410         "cfi_probe", "jedec_probe", "qinfo_probe", "map_rom",
 411 };
 412
 413 static const char * const part_probe_types[] = {
 414         "cmdlinepart", "RedBoot", "afs", NULL
 415 };
 416
 417 static int physmap_flash_pdata_init(struct platform_device *dev)
 418 {
 419         struct physmap_flash_info *info = platform_get_drvdata(dev);
 420         struct physmap_flash_data *physmap_data;
 421         unsigned int i;
 422         int err;
 423
 424         physmap_data = dev_get_platdata(&dev->dev);
 425         if (!physmap_data)
 426                 return -EINVAL;
 427
 428         info->probe_type = physmap_data->probe_type;
 429         info->part_types = physmap_data->part_probe_types ? : part_probe_types;
 430         info->parts = physmap_data->parts;
 431         info->nparts = physmap_data->nr_parts;
 432
 433         if (physmap_data->init) {
 434                 err = physmap_data->init(dev);
 435                 if (err)
 436                         return err;
 437         }
 438
 439         for (i = 0; i < info->nmaps; i++) {
 440                 info->maps[i].bankwidth = physmap_data->width;
 441                 info->maps[i].pfow_base = physmap_data->pfow_base;
 442                 info->maps[i].set_vpp = physmap_set_vpp;
 443         }
 444
 445         return 0;
 446 }
 447
 448 static int physmap_flash_probe(struct platform_device *dev)
 449 {
 450         struct physmap_flash_info *info;
 451         int err = 0;
 452         int i;
 453
 454         if (!dev->dev.of_node && !dev_get_platdata(&dev->dev))
 455                 return -EINVAL;
 456
 457         info = devm_kzalloc(&dev->dev, sizeof(*info), GFP_KERNEL);
 458         if (!info)
 459                 return -ENOMEM;
 460
 461         while (platform_get_resource(dev, IORESOURCE_MEM, info->nmaps))
 462                 info->nmaps++;
 463
 464         if (!info->nmaps)
 465                 return -ENODEV;
 466
 467         info->maps = devm_kzalloc(&dev->dev,
 468                                   sizeof(*info->maps) * info->nmaps,
 469                                   GFP_KERNEL);
 470         if (!info->maps)
 471                 return -ENOMEM;
 472
 473         info->mtds = devm_kzalloc(&dev->dev,
 474                                   sizeof(*info->mtds) * info->nmaps,
 475                                   GFP_KERNEL);
 476         if (!info->mtds)
 477                 return -ENOMEM;
 478
 479         platform_set_drvdata(dev, info);
 480
 481         info->gpios = devm_gpiod_get_array_optional(&dev->dev, "addr",
 482                                                     GPIOD_OUT_LOW);
 483         if (IS_ERR(info->gpios))
 484                 return PTR_ERR(info->gpios);
 485
 486         if (info->gpios && info->nmaps > 1) {
 487                 dev_err(&dev->dev, "addr-gpios only supported for nmaps == 1\n");
 488                 return -EINVAL;
 489         }
 490
 491         pm_runtime_enable(&dev->dev);
 492         pm_runtime_get_sync(&dev->dev);
 493
 494         if (dev->dev.of_node)
 495                 err = physmap_flash_of_init(dev);
 496         else
 497                 err = physmap_flash_pdata_init(dev);
 498
 499         if (err) {
 500                 pm_runtime_put(&dev->dev);
 501                 pm_runtime_disable(&dev->dev);
 502                 return err;
 503         }
 504
 505         for (i = 0; i < info->nmaps; i++) {
 506                 struct resource *res;
 507
 508                 res = platform_get_resource(dev, IORESOURCE_MEM, i);
 509                 info->maps[i].virt = devm_ioremap_resource(&dev->dev, res);
 510                 if (IS_ERR(info->maps[i].virt)) {
 511                         err = PTR_ERR(info->maps[i].virt);
 512                         goto err_out;
 513                 }
 514
 515                 dev_notice(&dev->dev, "physmap platform flash device: %pR\n",
 516                            res);
 517
 518                 info->maps[i].name = dev_name(&dev->dev);
 519
 520                 if (!info->maps[i].phys)
 521                         info->maps[i].phys = res->start;
 522
 523                 info->win_order = get_bitmask_order(resource_size(res)) - 1;
 524                 info->maps[i].size = BIT(info->win_order +
 525                                          (info->gpios ?
 526                                           info->gpios->ndescs : 0));
 527
 528                 info->maps[i].map_priv_1 = (unsigned long)dev;
 529
 530                 if (info->gpios) {
 531                         err = physmap_addr_gpios_map_init(&info->maps[i]);
 532                         if (err)
 533                                 goto err_out;
 534                 }
 535
 536 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 537                 /*
 538                  * Only use the simple_map implementation if map hooks are not
 539                  * implemented. Since map->read() is mandatory checking for its
 540                  * presence is enough.
 541                  */
 542                 if (!info->maps[i].read)
 543                         simple_map_init(&info->maps[i]);
 544 #else
 545                 simple_map_init(&info->maps[i]);
 546 #endif
 547
 548                 if (info->probe_type) {
 549                         info->mtds[i] = do_map_probe(info->probe_type,
 550                                                      &info->maps[i]);
 551                 } else {
 552                         int j;
 553
 554                         for (j = 0; j < ARRAY_SIZE(rom_probe_types); j++) {
 555                                 info->mtds[i] = do_map_probe(rom_probe_types[j],
 556                                                              &info->maps[i]);
 557                                 if (info->mtds[i])
 558                                         break;
 559                         }
 560                 }
 561
 562                 if (!info->mtds[i]) {
 563                         dev_err(&dev->dev, "map_probe failed\n");
 564                         err = -ENXIO;
 565                         goto err_out;
 566                 }
 567                 info->mtds[i]->dev.parent = &dev->dev;
 568         }
 569
 570         if (info->nmaps == 1) {
 571                 info->cmtd = info->mtds[0];
 572         } else {
 573                 /*
 574                  * We detected multiple devices. Concatenate them together.
 575                  */
 576                 info->cmtd = mtd_concat_create(info->mtds, info->nmaps,
 577                                                dev_name(&dev->dev));
 578                 if (!info->cmtd)
 579                         err = -ENXIO;
 580         }
 581         if (err)
 582                 goto err_out;
 583
 584         spin_lock_init(&info->vpp_lock);
 585
 586         mtd_set_of_node(info->cmtd, dev->dev.of_node);
 587         err = mtd_device_parse_register(info->cmtd, info->part_types, NULL,
 588                                         info->parts, info->nparts);
 589         if (err)
 590                 goto err_out;
 591
 592         return 0;
 593
 594 err_out:
 595         physmap_flash_remove(dev);
 596         return err;
 597 }
 598
 599 #ifdef CONFIG_PM
 600 static void physmap_flash_shutdown(struct platform_device *dev)
 601 {
 602         struct physmap_flash_info *info = platform_get_drvdata(dev);
 603         int i;
 604
 605         for (i = 0; i < info->nmaps && info->mtds[i]; i++)
 606                 if (mtd_suspend(info->mtds[i]) == 0)
 607                         mtd_resume(info->mtds[i]);
 608 }
 609 #else
 610 #define physmap_flash_shutdown NULL
 611 #endif
 612
 613 static struct platform_driver physmap_flash_driver = {
 614         .probe          = physmap_flash_probe,
 615         .remove         = physmap_flash_remove,
 616         .shutdown       = physmap_flash_shutdown,
 617         .driver         = {
 618                 .name   = "physmap-flash",
 619                 .of_match_table = of_flash_match,
 620         },
 621 };
 622
 623 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
 624 static struct physmap_flash_data physmap_flash_data = {
 625         .width          = CONFIG_MTD_PHYSMAP_BANKWIDTH,
 626 };
 627
 628 static struct resource physmap_flash_resource = {
 629         .start          = CONFIG_MTD_PHYSMAP_START,
 630         .end            = CONFIG_MTD_PHYSMAP_START + CONFIG_MTD_PHYSMAP_LEN - 1,
 631         .flags          = IORESOURCE_MEM,
 632 };
 633
 634 static struct platform_device physmap_flash = {
 635         .name           = "physmap-flash",
 636         .id             = 0,
 637         .dev            = {
 638                 .platform_data  = &physmap_flash_data,
 639         },
 640         .num_resources  = 1,
 641         .resource       = &physmap_flash_resource,
 642 };
 643 #endif
 644
 645 static int __init physmap_init(void)
 646 {
 647         int err;
 648
 649         err = platform_driver_register(&physmap_flash_driver);
 650 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
 651         if (err == 0) {
 652                 err = platform_device_register(&physmap_flash);
 653                 if (err)
 654                         platform_driver_unregister(&physmap_flash_driver);
 655         }
 656 #endif
 657
 658         return err;
 659 }
 660
 661 static void __exit physmap_exit(void)
 662 {
 663 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
 664         platform_device_unregister(&physmap_flash);
 665 #endif
 666         platform_driver_unregister(&physmap_flash_driver);
 667 }
 668
 669 module_init(physmap_init);
 670 module_exit(physmap_exit);
 671
 672 MODULE_LICENSE("GPL");
 673 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 674 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
 675 MODULE_AUTHOR("Mike Frysinger <vapier@gentoo.org>");
 676 MODULE_DESCRIPTION("Generic configurable MTD map driver");
 677
 678 /* legacy platform drivers can't hotplug or coldplg */
 679 #ifndef CONFIG_MTD_PHYSMAP_COMPAT
 680 /* work with hotplug and coldplug */
 681 MODULE_ALIAS("platform:physmap-flash");
 682 #endif