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