LXR linux/drivers/mtd/maps/ichxrom.c

   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * ichxrom.c
   4 *
   5 * Normal mappings of chips in physical memory
   6 */
   7
   8#include <linux/module.h>
   9#include <linux/types.h>
  10#include <linux/kernel.h>
  11#include <linux/init.h>
  12#include <linux/slab.h>
  13#include <asm/io.h>
  14#include <linux/mtd/mtd.h>
  15#include <linux/mtd/map.h>
  16#include <linux/mtd/cfi.h>
  17#include <linux/mtd/flashchip.h>
  18#include <linux/pci.h>
  19#include <linux/pci_ids.h>
  20#include <linux/list.h>
  21
  22#define xstr(s) str(s)
  23#define str(s) #s
  24#define MOD_NAME xstr(KBUILD_BASENAME)
  25
  26#define ADDRESS_NAME_LEN 18
  27
  28#define ROM_PROBE_STEP_SIZE (64*1024) /* 64KiB */
  29
  30#define BIOS_CNTL       0x4e
  31#define FWH_DEC_EN1     0xE3
  32#define FWH_DEC_EN2     0xF0
  33#define FWH_SEL1        0xE8
  34#define FWH_SEL2        0xEE
  35
  36struct ichxrom_window {
  37        void __iomem* virt;
  38        unsigned long phys;
  39        unsigned long size;
  40        struct list_head maps;
  41        struct resource rsrc;
  42        struct pci_dev *pdev;
  43};
  44
  45struct ichxrom_map_info {
  46        struct list_head list;
  47        struct map_info map;
  48        struct mtd_info *mtd;
  49        struct resource rsrc;
  50        char map_name[sizeof(MOD_NAME) + 2 + ADDRESS_NAME_LEN];
  51};
  52
  53static struct ichxrom_window ichxrom_window = {
  54        .maps = LIST_HEAD_INIT(ichxrom_window.maps),
  55};
  56
  57static void ichxrom_cleanup(struct ichxrom_window *window)
  58{
  59        struct ichxrom_map_info *map, *scratch;
  60        u16 word;
  61        int ret;
  62
  63        /* Disable writes through the rom window */
  64        ret = pci_read_config_word(window->pdev, BIOS_CNTL, &word);
  65        if (!ret)
  66                pci_write_config_word(window->pdev, BIOS_CNTL, word & ~1);
  67        pci_dev_put(window->pdev);
  68
  69        /* Free all of the mtd devices */
  70        list_for_each_entry_safe(map, scratch, &window->maps, list) {
  71                if (map->rsrc.parent)
  72                        release_resource(&map->rsrc);
  73                mtd_device_unregister(map->mtd);
  74                map_destroy(map->mtd);
  75                list_del(&map->list);
  76                kfree(map);
  77        }
  78        if (window->rsrc.parent)
  79                release_resource(&window->rsrc);
  80        if (window->virt) {
  81                iounmap(window->virt);
  82                window->virt = NULL;
  83                window->phys = 0;
  84                window->size = 0;
  85                window->pdev = NULL;
  86        }
  87}
  88
  89
  90static int __init ichxrom_init_one(struct pci_dev *pdev,
  91                                   const struct pci_device_id *ent)
  92{
  93        static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
  94        struct ichxrom_window *window = &ichxrom_window;
  95        struct ichxrom_map_info *map = NULL;
  96        unsigned long map_top;
  97        u8 byte;
  98        u16 word;
  99
 100        /* For now I just handle the ichx and I assume there
 101         * are not a lot of resources up at the top of the address
 102         * space.  It is possible to handle other devices in the
 103         * top 16MB but it is very painful.  Also since
 104         * you can only really attach a FWH to an ICHX there
 105         * a number of simplifications you can make.
 106         *
 107         * Also you can page firmware hubs if an 8MB window isn't enough
 108         * but don't currently handle that case either.
 109         */
 110        window->pdev = pdev;
 111
 112        /* Find a region continuous to the end of the ROM window  */
 113        window->phys = 0;
 114        pci_read_config_byte(pdev, FWH_DEC_EN1, &byte);
 115        if (byte == 0xff) {
 116                window->phys = 0xffc00000;
 117                pci_read_config_byte(pdev, FWH_DEC_EN2, &byte);
 118                if ((byte & 0x0f) == 0x0f) {
 119                        window->phys = 0xff400000;
 120                }
 121                else if ((byte & 0x0e) == 0x0e) {
 122                        window->phys = 0xff500000;
 123                }
 124                else if ((byte & 0x0c) == 0x0c) {
 125                        window->phys = 0xff600000;
 126                }
 127                else if ((byte & 0x08) == 0x08) {
 128                        window->phys = 0xff700000;
 129                }
 130        }
 131        else if ((byte & 0xfe) == 0xfe) {
 132                window->phys = 0xffc80000;
 133        }
 134        else if ((byte & 0xfc) == 0xfc) {
 135                window->phys = 0xffd00000;
 136        }
 137        else if ((byte & 0xf8) == 0xf8) {
 138                window->phys = 0xffd80000;
 139        }
 140        else if ((byte & 0xf0) == 0xf0) {
 141                window->phys = 0xffe00000;
 142        }
 143        else if ((byte & 0xe0) == 0xe0) {
 144                window->phys = 0xffe80000;
 145        }
 146        else if ((byte & 0xc0) == 0xc0) {
 147                window->phys = 0xfff00000;
 148        }
 149        else if ((byte & 0x80) == 0x80) {
 150                window->phys = 0xfff80000;
 151        }
 152
 153        if (window->phys == 0) {
 154                printk(KERN_ERR MOD_NAME ": Rom window is closed\n");
 155                goto out;
 156        }
 157        window->phys -= 0x400000UL;
 158        window->size = (0xffffffffUL - window->phys) + 1UL;
 159
 160        /* Enable writes through the rom window */
 161        pci_read_config_word(pdev, BIOS_CNTL, &word);
 162        if (!(word & 1)  && (word & (1<<1))) {
 163                /* The BIOS will generate an error if I enable
 164                 * this device, so don't even try.
 165                 */
 166                printk(KERN_ERR MOD_NAME ": firmware access control, I can't enable writes\n");
 167                goto out;
 168        }
 169        pci_write_config_word(pdev, BIOS_CNTL, word | 1);
 170
 171        /*
 172         * Try to reserve the window mem region.  If this fails then
 173         * it is likely due to the window being "reserved" by the BIOS.
 174         */
 175        window->rsrc.name = MOD_NAME;
 176        window->rsrc.start = window->phys;
 177        window->rsrc.end   = window->phys + window->size - 1;
 178        window->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 179        if (request_resource(&iomem_resource, &window->rsrc)) {
 180                window->rsrc.parent = NULL;
 181                printk(KERN_DEBUG MOD_NAME ": "
 182                       "%s(): Unable to register resource %pR - kernel bug?\n",
 183                       __func__, &window->rsrc);
 184        }
 185
 186        /* Map the firmware hub into my address space. */
 187        window->virt = ioremap_nocache(window->phys, window->size);
 188        if (!window->virt) {
 189                printk(KERN_ERR MOD_NAME ": ioremap(%08lx, %08lx) failed\n",
 190                        window->phys, window->size);
 191                goto out;
 192        }
 193
 194        /* Get the first address to look for an rom chip at */
 195        map_top = window->phys;
 196        if ((window->phys & 0x3fffff) != 0) {
 197                map_top = window->phys + 0x400000;
 198        }
 199#if 1
 200        /* The probe sequence run over the firmware hub lock
 201         * registers sets them to 0x7 (no access).
 202         * Probe at most the last 4M of the address space.
 203         */
 204        if (map_top < 0xffc00000) {
 205                map_top = 0xffc00000;
 206        }
 207#endif
 208        /* Loop through and look for rom chips */
 209        while((map_top - 1) < 0xffffffffUL) {
 210                struct cfi_private *cfi;
 211                unsigned long offset;
 212                int i;
 213
 214                if (!map) {
 215                        map = kmalloc(sizeof(*map), GFP_KERNEL);
 216                }
 217                if (!map) {
 218                        printk(KERN_ERR MOD_NAME ": kmalloc failed");
 219                        goto out;
 220                }
 221                memset(map, 0, sizeof(*map));
 222                INIT_LIST_HEAD(&map->list);
 223                map->map.name = map->map_name;
 224                map->map.phys = map_top;
 225                offset = map_top - window->phys;
 226                map->map.virt = (void __iomem *)
 227                        (((unsigned long)(window->virt)) + offset);
 228                map->map.size = 0xffffffffUL - map_top + 1UL;
 229                /* Set the name of the map to the address I am trying */
 230                sprintf(map->map_name, "%s @%08Lx",
 231                        MOD_NAME, (unsigned long long)map->map.phys);
 232
 233                /* Firmware hubs only use vpp when being programmed
 234                 * in a factory setting.  So in-place programming
 235                 * needs to use a different method.
 236                 */
 237                for(map->map.bankwidth = 32; map->map.bankwidth;
 238                        map->map.bankwidth >>= 1)
 239                {
 240                        char **probe_type;
 241                        /* Skip bankwidths that are not supported */
 242                        if (!map_bankwidth_supported(map->map.bankwidth))
 243                                continue;
 244
 245                        /* Setup the map methods */
 246                        simple_map_init(&map->map);
 247
 248                        /* Try all of the probe methods */
 249                        probe_type = rom_probe_types;
 250                        for(; *probe_type; probe_type++) {
 251                                map->mtd = do_map_probe(*probe_type, &map->map);
 252                                if (map->mtd)
 253                                        goto found;
 254                        }
 255                }
 256                map_top += ROM_PROBE_STEP_SIZE;
 257                continue;
 258        found:
 259                /* Trim the size if we are larger than the map */
 260                if (map->mtd->size > map->map.size) {
 261                        printk(KERN_WARNING MOD_NAME
 262                                " rom(%llu) larger than window(%lu). fixing...\n",
 263                                (unsigned long long)map->mtd->size, map->map.size);
 264                        map->mtd->size = map->map.size;
 265                }
 266                if (window->rsrc.parent) {
 267                        /*
 268                         * Registering the MTD device in iomem may not be possible
 269                         * if there is a BIOS "reserved" and BUSY range.  If this
 270                         * fails then continue anyway.
 271                         */
 272                        map->rsrc.name  = map->map_name;
 273                        map->rsrc.start = map->map.phys;
 274                        map->rsrc.end   = map->map.phys + map->mtd->size - 1;
 275                        map->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 276                        if (request_resource(&window->rsrc, &map->rsrc)) {
 277                                printk(KERN_ERR MOD_NAME
 278                                        ": cannot reserve MTD resource\n");
 279                                map->rsrc.parent = NULL;
 280                        }
 281                }
 282
 283                /* Make the whole region visible in the map */
 284                map->map.virt = window->virt;
 285                map->map.phys = window->phys;
 286                cfi = map->map.fldrv_priv;
 287                for(i = 0; i < cfi->numchips; i++) {
 288                        cfi->chips[i].start += offset;
 289                }
 290
 291                /* Now that the mtd devices is complete claim and export it */
 292                map->mtd->owner = THIS_MODULE;
 293                if (mtd_device_register(map->mtd, NULL, 0)) {
 294                        map_destroy(map->mtd);
 295                        map->mtd = NULL;
 296                        goto out;
 297                }
 298
 299
 300                /* Calculate the new value of map_top */
 301                map_top += map->mtd->size;
 302
 303                /* File away the map structure */
 304                list_add(&map->list, &window->maps);
 305                map = NULL;
 306        }
 307
 308 out:
 309        /* Free any left over map structures */
 310        kfree(map);
 311
 312        /* See if I have any map structures */
 313        if (list_empty(&window->maps)) {
 314                ichxrom_cleanup(window);
 315                return -ENODEV;
 316        }
 317        return 0;
 318}
 319
 320
 321static void ichxrom_remove_one(struct pci_dev *pdev)
 322{
 323        struct ichxrom_window *window = &ichxrom_window;
 324        ichxrom_cleanup(window);
 325}
 326
 327static const struct pci_device_id ichxrom_pci_tbl[] = {
 328        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_0,
 329          PCI_ANY_ID, PCI_ANY_ID, },
 330        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_0,
 331          PCI_ANY_ID, PCI_ANY_ID, },
 332        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
 333          PCI_ANY_ID, PCI_ANY_ID, },
 334        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_0,
 335          PCI_ANY_ID, PCI_ANY_ID, },
 336        { PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_1,
 337          PCI_ANY_ID, PCI_ANY_ID, },
 338        { 0, },
 339};
 340
 341#if 0
 342MODULE_DEVICE_TABLE(pci, ichxrom_pci_tbl);
 343
 344static struct pci_driver ichxrom_driver = {
 345        .name =         MOD_NAME,
 346        .id_table =     ichxrom_pci_tbl,
 347        .probe =        ichxrom_init_one,
 348        .remove =       ichxrom_remove_one,
 349};
 350#endif
 351
 352static int __init init_ichxrom(void)
 353{
 354        struct pci_dev *pdev;
 355        const struct pci_device_id *id;
 356
 357        pdev = NULL;
 358        for (id = ichxrom_pci_tbl; id->vendor; id++) {
 359                pdev = pci_get_device(id->vendor, id->device, NULL);
 360                if (pdev) {
 361                        break;
 362                }
 363        }
 364        if (pdev) {
 365                return ichxrom_init_one(pdev, &ichxrom_pci_tbl[0]);
 366        }
 367        return -ENXIO;
 368#if 0
 369        return pci_register_driver(&ichxrom_driver);
 370#endif
 371}
 372
 373static void __exit cleanup_ichxrom(void)
 374{
 375        ichxrom_remove_one(ichxrom_window.pdev);
 376}
 377
 378module_init(init_ichxrom);
 379module_exit(cleanup_ichxrom);
 380
 381MODULE_LICENSE("GPL");
 382MODULE_AUTHOR("Eric Biederman <ebiederman@lnxi.com>");
 383MODULE_DESCRIPTION("MTD map driver for BIOS chips on the ICHX southbridge");
 384