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
  36 struct 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
  45 struct 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
  53 static struct ichxrom_window ichxrom_window = {
  54         .maps = LIST_HEAD_INIT(ichxrom_window.maps),
  55 };
  56
  57 static 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
  90 static 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
 321 static void ichxrom_remove_one(struct pci_dev *pdev)
 322 {
 323         struct ichxrom_window *window = &ichxrom_window;
 324         ichxrom_cleanup(window);
 325 }
 326
 327 static 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
 342 MODULE_DEVICE_TABLE(pci, ichxrom_pci_tbl);
 343
 344 static 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
 352 static 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
 373 static void __exit cleanup_ichxrom(void)
 374 {
 375         ichxrom_remove_one(ichxrom_window.pdev);
 376 }
 377
 378 module_init(init_ichxrom);
 379 module_exit(cleanup_ichxrom);
 380
 381 MODULE_LICENSE("GPL");
 382 MODULE_AUTHOR("Eric Biederman <ebiederman@lnxi.com>");
 383 MODULE_DESCRIPTION("MTD map driver for BIOS chips on the ICHX southbridge");