linux/drivers/mtd/maps/physmap-core.c
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   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-bt1-rom.h"
  45#include "physmap-gemini.h"
  46#include "physmap-ixp4xx.h"
  47#include "physmap-versatile.h"
  48
  49struct physmap_flash_info {
  50        unsigned int            nmaps;
  51        struct mtd_info         **mtds;
  52        struct mtd_info         *cmtd;
  53        struct map_info         *maps;
  54        spinlock_t              vpp_lock;
  55        int                     vpp_refcnt;
  56        const char              *probe_type;
  57        const char * const      *part_types;
  58        unsigned int            nparts;
  59        const struct mtd_partition *parts;
  60        struct gpio_descs       *gpios;
  61        unsigned int            gpio_values;
  62        unsigned int            win_order;
  63};
  64
  65static int physmap_flash_remove(struct platform_device *dev)
  66{
  67        struct physmap_flash_info *info;
  68        struct physmap_flash_data *physmap_data;
  69        int i, err = 0;
  70
  71        info = platform_get_drvdata(dev);
  72        if (!info) {
  73                err = -EINVAL;
  74                goto out;
  75        }
  76
  77        if (info->cmtd) {
  78                err = mtd_device_unregister(info->cmtd);
  79                if (err)
  80                        goto out;
  81
  82                if (info->cmtd != info->mtds[0])
  83                        mtd_concat_destroy(info->cmtd);
  84        }
  85
  86        for (i = 0; i < info->nmaps; i++) {
  87                if (info->mtds[i])
  88                        map_destroy(info->mtds[i]);
  89        }
  90
  91        physmap_data = dev_get_platdata(&dev->dev);
  92        if (physmap_data && physmap_data->exit)
  93                physmap_data->exit(dev);
  94
  95out:
  96        pm_runtime_put(&dev->dev);
  97        pm_runtime_disable(&dev->dev);
  98        return err;
  99}
 100
 101static void physmap_set_vpp(struct map_info *map, int state)
 102{
 103        struct platform_device *pdev;
 104        struct physmap_flash_data *physmap_data;
 105        struct physmap_flash_info *info;
 106        unsigned long flags;
 107
 108        pdev = (struct platform_device *)map->map_priv_1;
 109        physmap_data = dev_get_platdata(&pdev->dev);
 110
 111        if (!physmap_data->set_vpp)
 112                return;
 113
 114        info = platform_get_drvdata(pdev);
 115
 116        spin_lock_irqsave(&info->vpp_lock, flags);
 117        if (state) {
 118                if (++info->vpp_refcnt == 1)    /* first nested 'on' */
 119                        physmap_data->set_vpp(pdev, 1);
 120        } else {
 121                if (--info->vpp_refcnt == 0)    /* last nested 'off' */
 122                        physmap_data->set_vpp(pdev, 0);
 123        }
 124        spin_unlock_irqrestore(&info->vpp_lock, flags);
 125}
 126
 127#if IS_ENABLED(CONFIG_MTD_PHYSMAP_GPIO_ADDR)
 128static void physmap_set_addr_gpios(struct physmap_flash_info *info,
 129                                   unsigned long ofs)
 130{
 131        unsigned int i;
 132
 133        ofs >>= info->win_order;
 134        if (info->gpio_values == ofs)
 135                return;
 136
 137        for (i = 0; i < info->gpios->ndescs; i++) {
 138                if ((BIT(i) & ofs) == (BIT(i) & info->gpio_values))
 139                        continue;
 140
 141                gpiod_set_value(info->gpios->desc[i], !!(BIT(i) & ofs));
 142        }
 143
 144        info->gpio_values = ofs;
 145}
 146
 147#define win_mask(order)         (BIT(order) - 1)
 148
 149static map_word physmap_addr_gpios_read(struct map_info *map,
 150                                        unsigned long ofs)
 151{
 152        struct platform_device *pdev;
 153        struct physmap_flash_info *info;
 154        map_word mw;
 155        u16 word;
 156
 157        pdev = (struct platform_device *)map->map_priv_1;
 158        info = platform_get_drvdata(pdev);
 159        physmap_set_addr_gpios(info, ofs);
 160
 161        word = readw(map->virt + (ofs & win_mask(info->win_order)));
 162        mw.x[0] = word;
 163        return mw;
 164}
 165
 166static void physmap_addr_gpios_copy_from(struct map_info *map, void *buf,
 167                                         unsigned long ofs, ssize_t len)
 168{
 169        struct platform_device *pdev;
 170        struct physmap_flash_info *info;
 171
 172        pdev = (struct platform_device *)map->map_priv_1;
 173        info = platform_get_drvdata(pdev);
 174
 175        while (len) {
 176                unsigned int winofs = ofs & win_mask(info->win_order);
 177                unsigned int chunklen = min_t(unsigned int, len,
 178                                              BIT(info->win_order) - winofs);
 179
 180                physmap_set_addr_gpios(info, ofs);
 181                memcpy_fromio(buf, map->virt + winofs, chunklen);
 182                len -= chunklen;
 183                buf += chunklen;
 184                ofs += chunklen;
 185        }
 186}
 187
 188static void physmap_addr_gpios_write(struct map_info *map, map_word mw,
 189                                     unsigned long ofs)
 190{
 191        struct platform_device *pdev;
 192        struct physmap_flash_info *info;
 193        u16 word;
 194
 195        pdev = (struct platform_device *)map->map_priv_1;
 196        info = platform_get_drvdata(pdev);
 197        physmap_set_addr_gpios(info, ofs);
 198
 199        word = mw.x[0];
 200        writew(word, map->virt + (ofs & win_mask(info->win_order)));
 201}
 202
 203static void physmap_addr_gpios_copy_to(struct map_info *map, unsigned long ofs,
 204                                       const void *buf, ssize_t len)
 205{
 206        struct platform_device *pdev;
 207        struct physmap_flash_info *info;
 208
 209        pdev = (struct platform_device *)map->map_priv_1;
 210        info = platform_get_drvdata(pdev);
 211
 212        while (len) {
 213                unsigned int winofs = ofs & win_mask(info->win_order);
 214                unsigned int chunklen = min_t(unsigned int, len,
 215                                              BIT(info->win_order) - winofs);
 216
 217                physmap_set_addr_gpios(info, ofs);
 218                memcpy_toio(map->virt + winofs, buf, chunklen);
 219                len -= chunklen;
 220                buf += chunklen;
 221                ofs += chunklen;
 222        }
 223}
 224
 225static int physmap_addr_gpios_map_init(struct map_info *map)
 226{
 227        map->phys = NO_XIP;
 228        map->read = physmap_addr_gpios_read;
 229        map->copy_from = physmap_addr_gpios_copy_from;
 230        map->write = physmap_addr_gpios_write;
 231        map->copy_to = physmap_addr_gpios_copy_to;
 232
 233        return 0;
 234}
 235#else
 236static int physmap_addr_gpios_map_init(struct map_info *map)
 237{
 238        return -ENOTSUPP;
 239}
 240#endif
 241
 242#if IS_ENABLED(CONFIG_MTD_PHYSMAP_OF)
 243static const struct of_device_id of_flash_match[] = {
 244        {
 245                .compatible = "cfi-flash",
 246                .data = "cfi_probe",
 247        },
 248        {
 249                /*
 250                 * FIXME: JEDEC chips can't be safely and reliably
 251                 * probed, although the mtd code gets it right in
 252                 * practice most of the time.  We should use the
 253                 * vendor and device ids specified by the binding to
 254                 * bypass the heuristic probe code, but the mtd layer
 255                 * provides, at present, no interface for doing so
 256                 * :(.
 257                 */
 258                .compatible = "jedec-flash",
 259                .data = "jedec_probe",
 260        },
 261        {
 262                .compatible = "mtd-ram",
 263                .data = "map_ram",
 264        },
 265        {
 266                .compatible = "mtd-rom",
 267                .data = "map_rom",
 268        },
 269        {
 270                .type = "rom",
 271                .compatible = "direct-mapped"
 272        },
 273        { /* sentinel */ },
 274};
 275MODULE_DEVICE_TABLE(of, of_flash_match);
 276
 277static const char * const of_default_part_probes[] = {
 278        "cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL
 279};
 280
 281static const char * const *of_get_part_probes(struct platform_device *dev)
 282{
 283        struct device_node *dp = dev->dev.of_node;
 284        const char **res;
 285        int count;
 286
 287        count = of_property_count_strings(dp, "linux,part-probe");
 288        if (count < 0)
 289                return of_default_part_probes;
 290
 291        res = devm_kcalloc(&dev->dev, count + 1, sizeof(*res), GFP_KERNEL);
 292        if (!res)
 293                return NULL;
 294
 295        count = of_property_read_string_array(dp, "linux,part-probe", res,
 296                                              count);
 297        if (count < 0)
 298                return NULL;
 299
 300        return res;
 301}
 302
 303static const char *of_select_probe_type(struct platform_device *dev)
 304{
 305        struct device_node *dp = dev->dev.of_node;
 306        const struct of_device_id *match;
 307        const char *probe_type;
 308
 309        match = of_match_device(of_flash_match, &dev->dev);
 310        probe_type = match->data;
 311        if (probe_type)
 312                return probe_type;
 313
 314        dev_warn(&dev->dev,
 315                 "Device tree uses obsolete \"direct-mapped\" flash binding\n");
 316
 317        of_property_read_string(dp, "probe-type", &probe_type);
 318        if (!probe_type)
 319                return NULL;
 320
 321        if (!strcmp(probe_type, "CFI")) {
 322                probe_type = "cfi_probe";
 323        } else if (!strcmp(probe_type, "JEDEC")) {
 324                probe_type = "jedec_probe";
 325        } else if (!strcmp(probe_type, "ROM")) {
 326                probe_type = "map_rom";
 327        } else {
 328                dev_warn(&dev->dev,
 329                         "obsolete_probe: don't know probe type '%s', mapping as rom\n",
 330                         probe_type);
 331                probe_type = "map_rom";
 332        }
 333
 334        return probe_type;
 335}
 336
 337static int physmap_flash_of_init(struct platform_device *dev)
 338{
 339        struct physmap_flash_info *info = platform_get_drvdata(dev);
 340        struct device_node *dp = dev->dev.of_node;
 341        const char *mtd_name = NULL;
 342        int err, swap = 0;
 343        bool map_indirect;
 344        unsigned int i;
 345        u32 bankwidth;
 346
 347        if (!dp)
 348                return -EINVAL;
 349
 350        info->probe_type = of_select_probe_type(dev);
 351
 352        info->part_types = of_get_part_probes(dev);
 353        if (!info->part_types)
 354                return -ENOMEM;
 355
 356        of_property_read_string(dp, "linux,mtd-name", &mtd_name);
 357
 358        map_indirect = of_property_read_bool(dp, "no-unaligned-direct-access");
 359
 360        err = of_property_read_u32(dp, "bank-width", &bankwidth);
 361        if (err) {
 362                dev_err(&dev->dev, "Can't get bank width from device tree\n");
 363                return err;
 364        }
 365
 366        if (of_property_read_bool(dp, "big-endian"))
 367                swap = CFI_BIG_ENDIAN;
 368        else if (of_property_read_bool(dp, "little-endian"))
 369                swap = CFI_LITTLE_ENDIAN;
 370
 371        for (i = 0; i < info->nmaps; i++) {
 372                info->maps[i].name = mtd_name;
 373                info->maps[i].swap = swap;
 374                info->maps[i].bankwidth = bankwidth;
 375                info->maps[i].device_node = dp;
 376
 377                err = of_flash_probe_bt1_rom(dev, dp, &info->maps[i]);
 378                if (err)
 379                        return err;
 380
 381                err = of_flash_probe_gemini(dev, dp, &info->maps[i]);
 382                if (err)
 383                        return err;
 384
 385                err = of_flash_probe_ixp4xx(dev, dp, &info->maps[i]);
 386                if (err)
 387                        return err;
 388
 389                err = of_flash_probe_versatile(dev, dp, &info->maps[i]);
 390                if (err)
 391                        return err;
 392
 393                /*
 394                 * On some platforms (e.g. MPC5200) a direct 1:1 mapping
 395                 * may cause problems with JFFS2 usage, as the local bus (LPB)
 396                 * doesn't support unaligned accesses as implemented in the
 397                 * JFFS2 code via memcpy(). By setting NO_XIP, the
 398                 * flash will not be exposed directly to the MTD users
 399                 * (e.g. JFFS2) any more.
 400                 */
 401                if (map_indirect)
 402                        info->maps[i].phys = NO_XIP;
 403        }
 404
 405        return 0;
 406}
 407#else /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
 408#define of_flash_match NULL
 409
 410static int physmap_flash_of_init(struct platform_device *dev)
 411{
 412        return -ENOTSUPP;
 413}
 414#endif /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
 415
 416static const char * const rom_probe_types[] = {
 417        "cfi_probe", "jedec_probe", "qinfo_probe", "map_rom",
 418};
 419
 420static const char * const part_probe_types[] = {
 421        "cmdlinepart", "RedBoot", "afs", NULL
 422};
 423
 424static int physmap_flash_pdata_init(struct platform_device *dev)
 425{
 426        struct physmap_flash_info *info = platform_get_drvdata(dev);
 427        struct physmap_flash_data *physmap_data;
 428        unsigned int i;
 429        int err;
 430
 431        physmap_data = dev_get_platdata(&dev->dev);
 432        if (!physmap_data)
 433                return -EINVAL;
 434
 435        info->probe_type = physmap_data->probe_type;
 436        info->part_types = physmap_data->part_probe_types ? : part_probe_types;
 437        info->parts = physmap_data->parts;
 438        info->nparts = physmap_data->nr_parts;
 439
 440        if (physmap_data->init) {
 441                err = physmap_data->init(dev);
 442                if (err)
 443                        return err;
 444        }
 445
 446        for (i = 0; i < info->nmaps; i++) {
 447                info->maps[i].bankwidth = physmap_data->width;
 448                info->maps[i].pfow_base = physmap_data->pfow_base;
 449                info->maps[i].set_vpp = physmap_set_vpp;
 450        }
 451
 452        return 0;
 453}
 454
 455static int physmap_flash_probe(struct platform_device *dev)
 456{
 457        struct physmap_flash_info *info;
 458        int err = 0;
 459        int i;
 460
 461        if (!dev->dev.of_node && !dev_get_platdata(&dev->dev))
 462                return -EINVAL;
 463
 464        info = devm_kzalloc(&dev->dev, sizeof(*info), GFP_KERNEL);
 465        if (!info)
 466                return -ENOMEM;
 467
 468        while (platform_get_resource(dev, IORESOURCE_MEM, info->nmaps))
 469                info->nmaps++;
 470
 471        if (!info->nmaps)
 472                return -ENODEV;
 473
 474        info->maps = devm_kzalloc(&dev->dev,
 475                                  sizeof(*info->maps) * info->nmaps,
 476                                  GFP_KERNEL);
 477        if (!info->maps)
 478                return -ENOMEM;
 479
 480        info->mtds = devm_kzalloc(&dev->dev,
 481                                  sizeof(*info->mtds) * info->nmaps,
 482                                  GFP_KERNEL);
 483        if (!info->mtds)
 484                return -ENOMEM;
 485
 486        platform_set_drvdata(dev, info);
 487
 488        info->gpios = devm_gpiod_get_array_optional(&dev->dev, "addr",
 489                                                    GPIOD_OUT_LOW);
 490        if (IS_ERR(info->gpios))
 491                return PTR_ERR(info->gpios);
 492
 493        if (info->gpios && info->nmaps > 1) {
 494                dev_err(&dev->dev, "addr-gpios only supported for nmaps == 1\n");
 495                return -EINVAL;
 496        }
 497
 498        pm_runtime_enable(&dev->dev);
 499        pm_runtime_get_sync(&dev->dev);
 500
 501        if (dev->dev.of_node)
 502                err = physmap_flash_of_init(dev);
 503        else
 504                err = physmap_flash_pdata_init(dev);
 505
 506        if (err) {
 507                pm_runtime_put(&dev->dev);
 508                pm_runtime_disable(&dev->dev);
 509                return err;
 510        }
 511
 512        for (i = 0; i < info->nmaps; i++) {
 513                struct resource *res;
 514
 515                res = platform_get_resource(dev, IORESOURCE_MEM, i);
 516                info->maps[i].virt = devm_ioremap_resource(&dev->dev, res);
 517                if (IS_ERR(info->maps[i].virt)) {
 518                        err = PTR_ERR(info->maps[i].virt);
 519                        goto err_out;
 520                }
 521
 522                dev_notice(&dev->dev, "physmap platform flash device: %pR\n",
 523                           res);
 524
 525                if (!info->maps[i].name)
 526                        info->maps[i].name = dev_name(&dev->dev);
 527
 528                if (!info->maps[i].phys)
 529                        info->maps[i].phys = res->start;
 530
 531                info->win_order = get_bitmask_order(resource_size(res)) - 1;
 532                info->maps[i].size = BIT(info->win_order +
 533                                         (info->gpios ?
 534                                          info->gpios->ndescs : 0));
 535
 536                info->maps[i].map_priv_1 = (unsigned long)dev;
 537
 538                if (info->gpios) {
 539                        err = physmap_addr_gpios_map_init(&info->maps[i]);
 540                        if (err)
 541                                goto err_out;
 542                }
 543
 544#ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 545                /*
 546                 * Only use the simple_map implementation if map hooks are not
 547                 * implemented. Since map->read() is mandatory checking for its
 548                 * presence is enough.
 549                 */
 550                if (!info->maps[i].read)
 551                        simple_map_init(&info->maps[i]);
 552#else
 553                simple_map_init(&info->maps[i]);
 554#endif
 555
 556                if (info->probe_type) {
 557                        info->mtds[i] = do_map_probe(info->probe_type,
 558                                                     &info->maps[i]);
 559                } else {
 560                        int j;
 561
 562                        for (j = 0; j < ARRAY_SIZE(rom_probe_types); j++) {
 563                                info->mtds[i] = do_map_probe(rom_probe_types[j],
 564                                                             &info->maps[i]);
 565                                if (info->mtds[i])
 566                                        break;
 567                        }
 568                }
 569
 570                if (!info->mtds[i]) {
 571                        dev_err(&dev->dev, "map_probe failed\n");
 572                        err = -ENXIO;
 573                        goto err_out;
 574                }
 575                info->mtds[i]->dev.parent = &dev->dev;
 576        }
 577
 578        if (info->nmaps == 1) {
 579                info->cmtd = info->mtds[0];
 580        } else {
 581                /*
 582                 * We detected multiple devices. Concatenate them together.
 583                 */
 584                info->cmtd = mtd_concat_create(info->mtds, info->nmaps,
 585                                               dev_name(&dev->dev));
 586                if (!info->cmtd)
 587                        err = -ENXIO;
 588        }
 589        if (err)
 590                goto err_out;
 591
 592        spin_lock_init(&info->vpp_lock);
 593
 594        mtd_set_of_node(info->cmtd, dev->dev.of_node);
 595        err = mtd_device_parse_register(info->cmtd, info->part_types, NULL,
 596                                        info->parts, info->nparts);
 597        if (err)
 598                goto err_out;
 599
 600        return 0;
 601
 602err_out:
 603        physmap_flash_remove(dev);
 604        return err;
 605}
 606
 607#ifdef CONFIG_PM
 608static void physmap_flash_shutdown(struct platform_device *dev)
 609{
 610        struct physmap_flash_info *info = platform_get_drvdata(dev);
 611        int i;
 612
 613        for (i = 0; i < info->nmaps && info->mtds[i]; i++)
 614                if (mtd_suspend(info->mtds[i]) == 0)
 615                        mtd_resume(info->mtds[i]);
 616}
 617#else
 618#define physmap_flash_shutdown NULL
 619#endif
 620
 621static struct platform_driver physmap_flash_driver = {
 622        .probe          = physmap_flash_probe,
 623        .remove         = physmap_flash_remove,
 624        .shutdown       = physmap_flash_shutdown,
 625        .driver         = {
 626                .name   = "physmap-flash",
 627                .of_match_table = of_flash_match,
 628        },
 629};
 630
 631#ifdef CONFIG_MTD_PHYSMAP_COMPAT
 632static struct physmap_flash_data physmap_flash_data = {
 633        .width          = CONFIG_MTD_PHYSMAP_BANKWIDTH,
 634};
 635
 636static struct resource physmap_flash_resource = {
 637        .start          = CONFIG_MTD_PHYSMAP_START,
 638        .end            = CONFIG_MTD_PHYSMAP_START + CONFIG_MTD_PHYSMAP_LEN - 1,
 639        .flags          = IORESOURCE_MEM,
 640};
 641
 642static struct platform_device physmap_flash = {
 643        .name           = "physmap-flash",
 644        .id             = 0,
 645        .dev            = {
 646                .platform_data  = &physmap_flash_data,
 647        },
 648        .num_resources  = 1,
 649        .resource       = &physmap_flash_resource,
 650};
 651#endif
 652
 653static int __init physmap_init(void)
 654{
 655        int err;
 656
 657        err = platform_driver_register(&physmap_flash_driver);
 658#ifdef CONFIG_MTD_PHYSMAP_COMPAT
 659        if (err == 0) {
 660                err = platform_device_register(&physmap_flash);
 661                if (err)
 662                        platform_driver_unregister(&physmap_flash_driver);
 663        }
 664#endif
 665
 666        return err;
 667}
 668
 669static void __exit physmap_exit(void)
 670{
 671#ifdef CONFIG_MTD_PHYSMAP_COMPAT
 672        platform_device_unregister(&physmap_flash);
 673#endif
 674        platform_driver_unregister(&physmap_flash_driver);
 675}
 676
 677module_init(physmap_init);
 678module_exit(physmap_exit);
 679
 680MODULE_LICENSE("GPL");
 681MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 682MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
 683MODULE_AUTHOR("Mike Frysinger <vapier@gentoo.org>");
 684MODULE_DESCRIPTION("Generic configurable MTD map driver");
 685
 686/* legacy platform drivers can't hotplug or coldplg */
 687#ifndef CONFIG_MTD_PHYSMAP_COMPAT
 688/* work with hotplug and coldplug */
 689MODULE_ALIAS("platform:physmap-flash");
 690#endif
 691