drivers/mtd/maps/ck804xrom.c

   1 /*
   2  * ck804xrom.c
   3  *
   4  * Normal mappings of chips in physical memory
   5  *
   6  * Dave Olsen <dolsen@lnxi.com>
   7  * Ryan Jackson <rjackson@lnxi.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/types.h>
  12 #include <linux/version.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <asm/io.h>
  16 #include <linux/mtd/mtd.h>
  17 #include <linux/mtd/map.h>
  18 #include <linux/mtd/cfi.h>
  19 #include <linux/mtd/flashchip.h>
  20 #include <linux/pci.h>
  21 #include <linux/pci_ids.h>
  22 #include <linux/list.h>
  23
  24
  25 #define MOD_NAME KBUILD_BASENAME
  26
  27 #define ADDRESS_NAME_LEN 18
  28
  29 #define ROM_PROBE_STEP_SIZE (64*1024)
  30
  31 struct ck804xrom_window {
  32         void __iomem *virt;
  33         unsigned long phys;
  34         unsigned long size;
  35         struct list_head maps;
  36         struct resource rsrc;
  37         struct pci_dev *pdev;
  38 };
  39
  40 struct ck804xrom_map_info {
  41         struct list_head list;
  42         struct map_info map;
  43         struct mtd_info *mtd;
  44         struct resource rsrc;
  45         char map_name[sizeof(MOD_NAME) + 2 + ADDRESS_NAME_LEN];
  46 };
  47
  48
  49 /* The 2 bits controlling the window size are often set to allow reading
  50  * the BIOS, but too small to allow writing, since the lock registers are
  51  * 4MiB lower in the address space than the data.
  52  *
  53  * This is intended to prevent flashing the bios, perhaps accidentally.
  54  *
  55  * This parameter allows the normal driver to override the BIOS settings.
  56  *
  57  * The bits are 6 and 7.  If both bits are set, it is a 5MiB window.
  58  * If only the 7 Bit is set, it is a 4MiB window.  Otherwise, a
  59  * 64KiB window.
  60  *
  61  */
  62 static uint win_size_bits = 0;
  63 module_param(win_size_bits, uint, 0);
  64 MODULE_PARM_DESC(win_size_bits, "ROM window size bits override for 0x88 byte, normally set by BIOS.");
  65
  66 static struct ck804xrom_window ck804xrom_window = {
  67         .maps = LIST_HEAD_INIT(ck804xrom_window.maps),
  68 };
  69
  70 static void ck804xrom_cleanup(struct ck804xrom_window *window)
  71 {
  72         struct ck804xrom_map_info *map, *scratch;
  73         u8 byte;
  74
  75         if (window->pdev) {
  76                 /* Disable writes through the rom window */
  77                 pci_read_config_byte(window->pdev, 0x6d, &byte);
  78                 pci_write_config_byte(window->pdev, 0x6d, byte & ~1);
  79         }
  80
  81         /* Free all of the mtd devices */
  82         list_for_each_entry_safe(map, scratch, &window->maps, list) {
  83                 if (map->rsrc.parent)
  84                         release_resource(&map->rsrc);
  85
  86                 del_mtd_device(map->mtd);
  87                 map_destroy(map->mtd);
  88                 list_del(&map->list);
  89                 kfree(map);
  90         }
  91         if (window->rsrc.parent)
  92                 release_resource(&window->rsrc);
  93
  94         if (window->virt) {
  95                 iounmap(window->virt);
  96                 window->virt = NULL;
  97                 window->phys = 0;
  98                 window->size = 0;
  99         }
 100         pci_dev_put(window->pdev);
 101 }
 102
 103
 104 static int __devinit ck804xrom_init_one (struct pci_dev *pdev,
 105         const struct pci_device_id *ent)
 106 {
 107         static char *rom_probe_types[] = { "cfi_probe", "jedec_probe", NULL };
 108         u8 byte;
 109         struct ck804xrom_window *window = &ck804xrom_window;
 110         struct ck804xrom_map_info *map = NULL;
 111         unsigned long map_top;
 112
 113         /* Remember the pci dev I find the window in */
 114         window->pdev = pci_dev_get(pdev);
 115
 116         /* Enable the selected rom window.  This is often incorrectly
 117          * set up by the BIOS, and the 4MiB offset for the lock registers
 118          * requires the full 5MiB of window space.
 119          *
 120          * This 'write, then read' approach leaves the bits for
 121          * other uses of the hardware info.
 122          */
 123         pci_read_config_byte(pdev, 0x88, &byte);
 124         pci_write_config_byte(pdev, 0x88, byte | win_size_bits );
 125
 126
 127         /* Assume the rom window is properly setup, and find it's size */
 128         pci_read_config_byte(pdev, 0x88, &byte);
 129
 130         if ((byte & ((1<<7)|(1<<6))) == ((1<<7)|(1<<6)))
 131                 window->phys = 0xffb00000; /* 5MiB */
 132         else if ((byte & (1<<7)) == (1<<7))
 133                 window->phys = 0xffc00000; /* 4MiB */
 134         else
 135                 window->phys = 0xffff0000; /* 64KiB */
 136
 137         window->size = 0xffffffffUL - window->phys + 1UL;
 138
 139         /*
 140          * Try to reserve the window mem region.  If this fails then
 141          * it is likely due to a fragment of the window being
 142          * "reserved" by the BIOS.  In the case that the
 143          * request_mem_region() fails then once the rom size is
 144          * discovered we will try to reserve the unreserved fragment.
 145          */
 146         window->rsrc.name = MOD_NAME;
 147         window->rsrc.start = window->phys;
 148         window->rsrc.end   = window->phys + window->size - 1;
 149         window->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 150         if (request_resource(&iomem_resource, &window->rsrc)) {
 151                 window->rsrc.parent = NULL;
 152                 printk(KERN_ERR MOD_NAME
 153                         " %s(): Unable to register resource"
 154                         " 0x%.016llx-0x%.016llx - kernel bug?\n",
 155                         __func__,
 156                         (unsigned long long)window->rsrc.start,
 157                         (unsigned long long)window->rsrc.end);
 158         }
 159
 160
 161         /* Enable writes through the rom window */
 162         pci_read_config_byte(pdev, 0x6d, &byte);
 163         pci_write_config_byte(pdev, 0x6d, byte | 1);
 164
 165         /* FIXME handle registers 0x80 - 0x8C the bios region locks */
 166
 167         /* For write accesses caches are useless */
 168         window->virt = ioremap_nocache(window->phys, window->size);
 169         if (!window->virt) {
 170                 printk(KERN_ERR MOD_NAME ": ioremap(%08lx, %08lx) failed\n",
 171                         window->phys, window->size);
 172                 goto out;
 173         }
 174
 175         /* Get the first address to look for a rom chip at */
 176         map_top = window->phys;
 177 #if 1
 178         /* The probe sequence run over the firmware hub lock
 179          * registers sets them to 0x7 (no access).
 180          * Probe at most the last 4MiB of the address space.
 181          */
 182         if (map_top < 0xffc00000)
 183                 map_top = 0xffc00000;
 184 #endif
 185         /* Loop  through and look for rom chips.  Since we don't know the
 186          * starting address for each chip, probe every ROM_PROBE_STEP_SIZE
 187          * bytes from the starting address of the window.
 188          */
 189         while((map_top - 1) < 0xffffffffUL) {
 190                 struct cfi_private *cfi;
 191                 unsigned long offset;
 192                 int i;
 193
 194                 if (!map)
 195                         map = kmalloc(sizeof(*map), GFP_KERNEL);
 196
 197                 if (!map) {
 198                         printk(KERN_ERR MOD_NAME ": kmalloc failed");
 199                         goto out;
 200                 }
 201                 memset(map, 0, sizeof(*map));
 202                 INIT_LIST_HEAD(&map->list);
 203                 map->map.name = map->map_name;
 204                 map->map.phys = map_top;
 205                 offset = map_top - window->phys;
 206                 map->map.virt = (void __iomem *)
 207                         (((unsigned long)(window->virt)) + offset);
 208                 map->map.size = 0xffffffffUL - map_top + 1UL;
 209                 /* Set the name of the map to the address I am trying */
 210                 sprintf(map->map_name, "%s @%08lx",
 211                         MOD_NAME, map->map.phys);
 212
 213                 /* There is no generic VPP support */
 214                 for(map->map.bankwidth = 32; map->map.bankwidth;
 215                         map->map.bankwidth >>= 1)
 216                 {
 217                         char **probe_type;
 218                         /* Skip bankwidths that are not supported */
 219                         if (!map_bankwidth_supported(map->map.bankwidth))
 220                                 continue;
 221
 222                         /* Setup the map methods */
 223                         simple_map_init(&map->map);
 224
 225                         /* Try all of the probe methods */
 226                         probe_type = rom_probe_types;
 227                         for(; *probe_type; probe_type++) {
 228                                 map->mtd = do_map_probe(*probe_type, &map->map);
 229                                 if (map->mtd)
 230                                         goto found;
 231                         }
 232                 }
 233                 map_top += ROM_PROBE_STEP_SIZE;
 234                 continue;
 235         found:
 236                 /* Trim the size if we are larger than the map */
 237                 if (map->mtd->size > map->map.size) {
 238                         printk(KERN_WARNING MOD_NAME
 239                                 " rom(%u) larger than window(%lu). fixing...\n",
 240                                 map->mtd->size, map->map.size);
 241                         map->mtd->size = map->map.size;
 242                 }
 243                 if (window->rsrc.parent) {
 244                         /*
 245                          * Registering the MTD device in iomem may not be possible
 246                          * if there is a BIOS "reserved" and BUSY range.  If this
 247                          * fails then continue anyway.
 248                          */
 249                         map->rsrc.name  = map->map_name;
 250                         map->rsrc.start = map->map.phys;
 251                         map->rsrc.end   = map->map.phys + map->mtd->size - 1;
 252                         map->rsrc.flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 253                         if (request_resource(&window->rsrc, &map->rsrc)) {
 254                                 printk(KERN_ERR MOD_NAME
 255                                         ": cannot reserve MTD resource\n");
 256                                 map->rsrc.parent = NULL;
 257                         }
 258                 }
 259
 260                 /* Make the whole region visible in the map */
 261                 map->map.virt = window->virt;
 262                 map->map.phys = window->phys;
 263                 cfi = map->map.fldrv_priv;
 264                 for(i = 0; i < cfi->numchips; i++)
 265                         cfi->chips[i].start += offset;
 266
 267                 /* Now that the mtd devices is complete claim and export it */
 268                 map->mtd->owner = THIS_MODULE;
 269                 if (add_mtd_device(map->mtd)) {
 270                         map_destroy(map->mtd);
 271                         map->mtd = NULL;
 272                         goto out;
 273                 }
 274
 275
 276                 /* Calculate the new value of map_top */
 277                 map_top += map->mtd->size;
 278
 279                 /* File away the map structure */
 280                 list_add(&map->list, &window->maps);
 281                 map = NULL;
 282         }
 283
 284  out:
 285         /* Free any left over map structures */
 286         if (map)
 287                 kfree(map);
 288
 289         /* See if I have any map structures */
 290         if (list_empty(&window->maps)) {
 291                 ck804xrom_cleanup(window);
 292                 return -ENODEV;
 293         }
 294         return 0;
 295 }
 296
 297
 298 static void __devexit ck804xrom_remove_one (struct pci_dev *pdev)
 299 {
 300         struct ck804xrom_window *window = &ck804xrom_window;
 301
 302         ck804xrom_cleanup(window);
 303 }
 304
 305 static struct pci_device_id ck804xrom_pci_tbl[] = {
 306         { PCI_VENDOR_ID_NVIDIA, 0x0051,
 307         PCI_ANY_ID, PCI_ANY_ID, }, /* nvidia ck804 */
 308         { 0, }
 309 };
 310
 311 MODULE_DEVICE_TABLE(pci, ck804xrom_pci_tbl);
 312
 313 #if 0
 314 static struct pci_driver ck804xrom_driver = {
 315         .name =         MOD_NAME,
 316         .id_table =     ck804xrom_pci_tbl,
 317         .probe =        ck804xrom_init_one,
 318         .remove =       ck804xrom_remove_one,
 319 };
 320 #endif
 321
 322 static int __init init_ck804xrom(void)
 323 {
 324         struct pci_dev *pdev;
 325         struct pci_device_id *id;
 326         int retVal;
 327         pdev = NULL;
 328
 329         for(id = ck804xrom_pci_tbl; id->vendor; id++) {
 330                 pdev = pci_find_device(id->vendor, id->device, NULL);
 331                 if (pdev)
 332                         break;
 333         }
 334         if (pdev) {
 335                 retVal = ck804xrom_init_one(pdev, &ck804xrom_pci_tbl[0]);
 336                 pci_dev_put(pdev);
 337                 return retVal;
 338         }
 339         return -ENXIO;
 340 #if 0
 341         return pci_module_init(&ck804xrom_driver);
 342 #endif
 343 }
 344
 345 static void __exit cleanup_ck804xrom(void)
 346 {
 347         ck804xrom_remove_one(ck804xrom_window.pdev);
 348 }
 349
 350 module_init(init_ck804xrom);
 351 module_exit(cleanup_ck804xrom);
 352
 353 MODULE_LICENSE("GPL");
 354 MODULE_AUTHOR("Eric Biederman <ebiederman@lnxi.com>, Dave Olsen <dolsen@lnxi.com>");
 355 MODULE_DESCRIPTION("MTD map driver for BIOS chips on the Nvidia ck804 southbridge");
 356