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