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