drivers/watchdog/ibmasr.c

   1 /*
   2  * IBM Automatic Server Restart driver.
   3  *
   4  * Copyright (c) 2005 Andrey Panin <pazke@donpac.ru>
   5  *
   6  * Based on driver written by Pete Reynolds.
   7  * Copyright (c) IBM Corporation, 1998-2004.
   8  *
   9  * This software may be used and distributed according to the terms
  10  * of the GNU Public License, incorporated herein by reference.
  11  */
  12
  13 #include <linux/fs.h>
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/module.h>
  17 #include <linux/pci.h>
  18 #include <linux/timer.h>
  19 #include <linux/miscdevice.h>
  20 #include <linux/watchdog.h>
  21 #include <linux/dmi.h>
  22 #include <linux/io.h>
  23 #include <linux/uaccess.h>
  24
  25
  26 enum {
  27         ASMTYPE_UNKNOWN,
  28         ASMTYPE_TOPAZ,
  29         ASMTYPE_JASPER,
  30         ASMTYPE_PEARL,
  31         ASMTYPE_JUNIPER,
  32         ASMTYPE_SPRUCE,
  33 };
  34
  35 #define PFX "ibmasr: "
  36
  37 #define TOPAZ_ASR_REG_OFFSET    4
  38 #define TOPAZ_ASR_TOGGLE        0x40
  39 #define TOPAZ_ASR_DISABLE       0x80
  40
  41 /* PEARL ASR S/W REGISTER SUPERIO PORT ADDRESSES */
  42 #define PEARL_BASE      0xe04
  43 #define PEARL_WRITE     0xe06
  44 #define PEARL_READ      0xe07
  45
  46 #define PEARL_ASR_DISABLE_MASK  0x80    /* bit 7: disable = 1, enable = 0 */
  47 #define PEARL_ASR_TOGGLE_MASK   0x40    /* bit 6: 0, then 1, then 0 */
  48
  49 /* JASPER OFFSET FROM SIO BASE ADDR TO ASR S/W REGISTERS. */
  50 #define JASPER_ASR_REG_OFFSET   0x38
  51
  52 #define JASPER_ASR_DISABLE_MASK 0x01    /* bit 0: disable = 1, enable = 0 */
  53 #define JASPER_ASR_TOGGLE_MASK  0x02    /* bit 1: 0, then 1, then 0 */
  54
  55 #define JUNIPER_BASE_ADDRESS    0x54b   /* Base address of Juniper ASR */
  56 #define JUNIPER_ASR_DISABLE_MASK 0x01   /* bit 0: disable = 1 enable = 0 */
  57 #define JUNIPER_ASR_TOGGLE_MASK 0x02    /* bit 1: 0, then 1, then 0 */
  58
  59 #define SPRUCE_BASE_ADDRESS     0x118e  /* Base address of Spruce ASR */
  60 #define SPRUCE_ASR_DISABLE_MASK 0x01    /* bit 1: disable = 1 enable = 0 */
  61 #define SPRUCE_ASR_TOGGLE_MASK  0x02    /* bit 0: 0, then 1, then 0 */
  62
  63
  64 static int nowayout = WATCHDOG_NOWAYOUT;
  65
  66 static unsigned long asr_is_open;
  67 static char asr_expect_close;
  68
  69 static unsigned int asr_type, asr_base, asr_length;
  70 static unsigned int asr_read_addr, asr_write_addr;
  71 static unsigned char asr_toggle_mask, asr_disable_mask;
  72 static spinlock_t asr_lock;
  73
  74 static void __asr_toggle(void)
  75 {
  76         unsigned char reg;
  77
  78         reg = inb(asr_read_addr);
  79
  80         outb(reg & ~asr_toggle_mask, asr_write_addr);
  81         reg = inb(asr_read_addr);
  82
  83         outb(reg | asr_toggle_mask, asr_write_addr);
  84         reg = inb(asr_read_addr);
  85
  86         outb(reg & ~asr_toggle_mask, asr_write_addr);
  87         reg = inb(asr_read_addr);
  88         spin_unlock(&asr_lock);
  89 }
  90
  91 static void asr_toggle(void)
  92 {
  93         spin_lock(&asr_lock);
  94         __asr_toggle();
  95         spin_unlock(&asr_lock);
  96 }
  97
  98 static void asr_enable(void)
  99 {
 100         unsigned char reg;
 101
 102         spin_lock(&asr_lock);
 103         if (asr_type == ASMTYPE_TOPAZ) {
 104                 /* asr_write_addr == asr_read_addr */
 105                 reg = inb(asr_read_addr);
 106                 outb(reg & ~(TOPAZ_ASR_TOGGLE | TOPAZ_ASR_DISABLE),
 107                      asr_read_addr);
 108         } else {
 109                 /*
 110                  * First make sure the hardware timer is reset by toggling
 111                  * ASR hardware timer line.
 112                  */
 113                 __asr_toggle();
 114
 115                 reg = inb(asr_read_addr);
 116                 outb(reg & ~asr_disable_mask, asr_write_addr);
 117         }
 118         reg = inb(asr_read_addr);
 119         spin_unlock(&asr_lock);
 120 }
 121
 122 static void asr_disable(void)
 123 {
 124         unsigned char reg;
 125
 126         spin_lock(&asr_lock);
 127         reg = inb(asr_read_addr);
 128
 129         if (asr_type == ASMTYPE_TOPAZ)
 130                 /* asr_write_addr == asr_read_addr */
 131                 outb(reg | TOPAZ_ASR_TOGGLE | TOPAZ_ASR_DISABLE,
 132                      asr_read_addr);
 133         else {
 134                 outb(reg | asr_toggle_mask, asr_write_addr);
 135                 reg = inb(asr_read_addr);
 136
 137                 outb(reg | asr_disable_mask, asr_write_addr);
 138         }
 139         reg = inb(asr_read_addr);
 140         spin_unlock(&asr_lock);
 141 }
 142
 143 static int __init asr_get_base_address(void)
 144 {
 145         unsigned char low, high;
 146         const char *type = "";
 147
 148         asr_length = 1;
 149
 150         switch (asr_type) {
 151         case ASMTYPE_TOPAZ:
 152                 /* SELECT SuperIO CHIP FOR QUERYING
 153                    (WRITE 0x07 TO BOTH 0x2E and 0x2F) */
 154                 outb(0x07, 0x2e);
 155                 outb(0x07, 0x2f);
 156
 157                 /* SELECT AND READ THE HIGH-NIBBLE OF THE GPIO BASE ADDRESS */
 158                 outb(0x60, 0x2e);
 159                 high = inb(0x2f);
 160
 161                 /* SELECT AND READ THE LOW-NIBBLE OF THE GPIO BASE ADDRESS */
 162                 outb(0x61, 0x2e);
 163                 low = inb(0x2f);
 164
 165                 asr_base = (high << 16) | low;
 166                 asr_read_addr = asr_write_addr =
 167                         asr_base + TOPAZ_ASR_REG_OFFSET;
 168                 asr_length = 5;
 169
 170                 break;
 171
 172         case ASMTYPE_JASPER:
 173                 type = "Jaspers ";
 174 #if 0
 175                 u32 r;
 176                 /* Suggested fix */
 177                 pdev = pci_get_bus_and_slot(0, DEVFN(0x1f, 0));
 178                 if (pdev == NULL)
 179                         return -ENODEV;
 180                 pci_read_config_dword(pdev, 0x58, &r);
 181                 asr_base = r & 0xFFFE;
 182                 pci_dev_put(pdev);
 183 #else
 184                 /* FIXME: need to use pci_config_lock here,
 185                    but it's not exported */
 186
 187 /*              spin_lock_irqsave(&pci_config_lock, flags);*/
 188
 189                 /* Select the SuperIO chip in the PCI I/O port register */
 190                 outl(0x8000f858, 0xcf8);
 191
 192                 /* BUS 0, Slot 1F, fnc 0, offset 58 */
 193
 194                 /*
 195                  * Read the base address for the SuperIO chip.
 196                  * Only the lower 16 bits are valid, but the address is word
 197                  * aligned so the last bit must be masked off.
 198                  */
 199                 asr_base = inl(0xcfc) & 0xfffe;
 200
 201 /*              spin_unlock_irqrestore(&pci_config_lock, flags);*/
 202 #endif
 203                 asr_read_addr = asr_write_addr =
 204                         asr_base + JASPER_ASR_REG_OFFSET;
 205                 asr_toggle_mask = JASPER_ASR_TOGGLE_MASK;
 206                 asr_disable_mask = JASPER_ASR_DISABLE_MASK;
 207                 asr_length = JASPER_ASR_REG_OFFSET + 1;
 208
 209                 break;
 210
 211         case ASMTYPE_PEARL:
 212                 type = "Pearls ";
 213                 asr_base = PEARL_BASE;
 214                 asr_read_addr = PEARL_READ;
 215                 asr_write_addr = PEARL_WRITE;
 216                 asr_toggle_mask = PEARL_ASR_TOGGLE_MASK;
 217                 asr_disable_mask = PEARL_ASR_DISABLE_MASK;
 218                 asr_length = 4;
 219                 break;
 220
 221         case ASMTYPE_JUNIPER:
 222                 type = "Junipers ";
 223                 asr_base = JUNIPER_BASE_ADDRESS;
 224                 asr_read_addr = asr_write_addr = asr_base;
 225                 asr_toggle_mask = JUNIPER_ASR_TOGGLE_MASK;
 226                 asr_disable_mask = JUNIPER_ASR_DISABLE_MASK;
 227                 break;
 228
 229         case ASMTYPE_SPRUCE:
 230                 type = "Spruce's ";
 231                 asr_base = SPRUCE_BASE_ADDRESS;
 232                 asr_read_addr = asr_write_addr = asr_base;
 233                 asr_toggle_mask = SPRUCE_ASR_TOGGLE_MASK;
 234                 asr_disable_mask = SPRUCE_ASR_DISABLE_MASK;
 235                 break;
 236         }
 237
 238         if (!request_region(asr_base, asr_length, "ibmasr")) {
 239                 printk(KERN_ERR PFX "address %#x already in use\n",
 240                         asr_base);
 241                 return -EBUSY;
 242         }
 243
 244         printk(KERN_INFO PFX "found %sASR @ addr %#x\n", type, asr_base);
 245
 246         return 0;
 247 }
 248
 249
 250 static ssize_t asr_write(struct file *file, const char __user *buf,
 251                          size_t count, loff_t *ppos)
 252 {
 253         if (count) {
 254                 if (!nowayout) {
 255                         size_t i;
 256
 257                         /* In case it was set long ago */
 258                         asr_expect_close = 0;
 259
 260                         for (i = 0; i != count; i++) {
 261                                 char c;
 262                                 if (get_user(c, buf + i))
 263                                         return -EFAULT;
 264                                 if (c == 'V')
 265                                         asr_expect_close = 42;
 266                         }
 267                 }
 268                 asr_toggle();
 269         }
 270         return count;
 271 }
 272
 273 static long asr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 274 {
 275         static const struct watchdog_info ident = {
 276                 .options =      WDIOF_KEEPALIVEPING |
 277                                 WDIOF_MAGICCLOSE,
 278                 .identity =     "IBM ASR",
 279         };
 280         void __user *argp = (void __user *)arg;
 281         int __user *p = argp;
 282         int heartbeat;
 283
 284         switch (cmd) {
 285         case WDIOC_GETSUPPORT:
 286                 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
 287         case WDIOC_GETSTATUS:
 288         case WDIOC_GETBOOTSTATUS:
 289                 return put_user(0, p);
 290         case WDIOC_SETOPTIONS:
 291         {
 292                 int new_options, retval = -EINVAL;
 293                 if (get_user(new_options, p))
 294                         return -EFAULT;
 295                 if (new_options & WDIOS_DISABLECARD) {
 296                         asr_disable();
 297                         retval = 0;
 298                 }
 299                 if (new_options & WDIOS_ENABLECARD) {
 300                         asr_enable();
 301                         asr_toggle();
 302                         retval = 0;
 303                 }
 304                 return retval;
 305         }
 306         case WDIOC_KEEPALIVE:
 307                 asr_toggle();
 308                 return 0;
 309         /*
 310          * The hardware has a fixed timeout value, so no WDIOC_SETTIMEOUT
 311          * and WDIOC_GETTIMEOUT always returns 256.
 312          */
 313         case WDIOC_GETTIMEOUT:
 314                 heartbeat = 256;
 315                 return put_user(heartbeat, p);
 316         default:
 317                 return -ENOTTY;
 318         }
 319 }
 320
 321 static int asr_open(struct inode *inode, struct file *file)
 322 {
 323         if (test_and_set_bit(0, &asr_is_open))
 324                 return -EBUSY;
 325
 326         asr_toggle();
 327         asr_enable();
 328
 329         return nonseekable_open(inode, file);
 330 }
 331
 332 static int asr_release(struct inode *inode, struct file *file)
 333 {
 334         if (asr_expect_close == 42)
 335                 asr_disable();
 336         else {
 337                 printk(KERN_CRIT PFX
 338                                 "unexpected close, not stopping watchdog!\n");
 339                 asr_toggle();
 340         }
 341         clear_bit(0, &asr_is_open);
 342         asr_expect_close = 0;
 343         return 0;
 344 }
 345
 346 static const struct file_operations asr_fops = {
 347         .owner =                THIS_MODULE,
 348         .llseek =               no_llseek,
 349         .write =                asr_write,
 350         .unlocked_ioctl =       asr_ioctl,
 351         .open =                 asr_open,
 352         .release =              asr_release,
 353 };
 354
 355 static struct miscdevice asr_miscdev = {
 356         .minor =        WATCHDOG_MINOR,
 357         .name =         "watchdog",
 358         .fops =         &asr_fops,
 359 };
 360
 361
 362 struct ibmasr_id {
 363         const char *desc;
 364         int type;
 365 };
 366
 367 static struct ibmasr_id __initdata ibmasr_id_table[] = {
 368         { "IBM Automatic Server Restart - eserver xSeries 220", ASMTYPE_TOPAZ },
 369         { "IBM Automatic Server Restart - Machine Type 8673", ASMTYPE_PEARL },
 370         { "IBM Automatic Server Restart - Machine Type 8480", ASMTYPE_JASPER },
 371         { "IBM Automatic Server Restart - Machine Type 8482", ASMTYPE_JUNIPER },
 372         { "IBM Automatic Server Restart - Machine Type 8648", ASMTYPE_SPRUCE },
 373         { NULL }
 374 };
 375
 376 static int __init ibmasr_init(void)
 377 {
 378         struct ibmasr_id *id;
 379         int rc;
 380
 381         for (id = ibmasr_id_table; id->desc; id++) {
 382                 if (dmi_find_device(DMI_DEV_TYPE_OTHER, id->desc, NULL)) {
 383                         asr_type = id->type;
 384                         break;
 385                 }
 386         }
 387
 388         if (!asr_type)
 389                 return -ENODEV;
 390
 391         spin_lock_init(&asr_lock);
 392
 393         rc = asr_get_base_address();
 394         if (rc)
 395                 return rc;
 396
 397         rc = misc_register(&asr_miscdev);
 398         if (rc < 0) {
 399                 release_region(asr_base, asr_length);
 400                 printk(KERN_ERR PFX "failed to register misc device\n");
 401                 return rc;
 402         }
 403
 404         return 0;
 405 }
 406
 407 static void __exit ibmasr_exit(void)
 408 {
 409         if (!nowayout)
 410                 asr_disable();
 411
 412         misc_deregister(&asr_miscdev);
 413
 414         release_region(asr_base, asr_length);
 415 }
 416
 417 module_init(ibmasr_init);
 418 module_exit(ibmasr_exit);
 419
 420 module_param(nowayout, int, 0);
 421 MODULE_PARM_DESC(nowayout,
 422         "Watchdog cannot be stopped once started (default="
 423                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 424
 425 MODULE_DESCRIPTION("IBM Automatic Server Restart driver");
 426 MODULE_AUTHOR("Andrey Panin");
 427 MODULE_LICENSE("GPL");
 428 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);