drivers/watchdog/hpwdt.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *      HPE WatchDog Driver
   4  *      based on
   5  *
   6  *      SoftDog 0.05:   A Software Watchdog Device
   7  *
   8  *      (c) Copyright 2018 Hewlett Packard Enterprise Development LP
   9  *      Thomas Mingarelli <thomas.mingarelli@hpe.com>
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/device.h>
  15 #include <linux/io.h>
  16 #include <linux/kernel.h>
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/pci.h>
  20 #include <linux/pci_ids.h>
  21 #include <linux/types.h>
  22 #include <linux/watchdog.h>
  23 #include <asm/nmi.h>
  24 #include <linux/crash_dump.h>
  25
  26 #define HPWDT_VERSION                   "2.0.4"
  27 #define SECS_TO_TICKS(secs)             ((secs) * 1000 / 128)
  28 #define TICKS_TO_SECS(ticks)            ((ticks) * 128 / 1000)
  29 #define HPWDT_MAX_TICKS                 65535
  30 #define HPWDT_MAX_TIMER                 TICKS_TO_SECS(HPWDT_MAX_TICKS)
  31 #define DEFAULT_MARGIN                  30
  32 #define PRETIMEOUT_SEC                  9
  33
  34 static bool ilo5;
  35 static unsigned int soft_margin = DEFAULT_MARGIN;       /* in seconds */
  36 static bool nowayout = WATCHDOG_NOWAYOUT;
  37 static bool pretimeout = IS_ENABLED(CONFIG_HPWDT_NMI_DECODING);
  38 static int kdumptimeout = -1;
  39
  40 static void __iomem *pci_mem_addr;              /* the PCI-memory address */
  41 static unsigned long __iomem *hpwdt_nmistat;
  42 static unsigned long __iomem *hpwdt_timer_reg;
  43 static unsigned long __iomem *hpwdt_timer_con;
  44
  45 static const struct pci_device_id hpwdt_devices[] = {
  46         { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) },   /* iLO2 */
  47         { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) },       /* iLO3 */
  48         {0},                    /* terminate list */
  49 };
  50 MODULE_DEVICE_TABLE(pci, hpwdt_devices);
  51
  52 static const struct pci_device_id hpwdt_blacklist[] = {
  53         { PCI_DEVICE_SUB(PCI_VENDOR_ID_HP, 0x3306, PCI_VENDOR_ID_HP, 0x1979) }, /* auxilary iLO */
  54         { PCI_DEVICE_SUB(PCI_VENDOR_ID_HP, 0x3306, PCI_VENDOR_ID_HP_3PAR, 0x0289) },  /* CL */
  55         {0},                    /* terminate list */
  56 };
  57
  58 static struct watchdog_device hpwdt_dev;
  59 /*
  60  *      Watchdog operations
  61  */
  62 static int hpwdt_hw_is_running(void)
  63 {
  64         return ioread8(hpwdt_timer_con) & 0x01;
  65 }
  66
  67 static int hpwdt_start(struct watchdog_device *wdd)
  68 {
  69         int control = 0x81 | (pretimeout ? 0x4 : 0);
  70         int reload = SECS_TO_TICKS(min(wdd->timeout, wdd->max_hw_heartbeat_ms/1000));
  71
  72         dev_dbg(wdd->parent, "start watchdog 0x%08x:0x%08x:0x%02x\n", wdd->timeout, reload, control);
  73         iowrite16(reload, hpwdt_timer_reg);
  74         iowrite8(control, hpwdt_timer_con);
  75
  76         return 0;
  77 }
  78
  79 static void hpwdt_stop(void)
  80 {
  81         unsigned long data;
  82
  83         pr_debug("stop  watchdog\n");
  84
  85         data = ioread8(hpwdt_timer_con);
  86         data &= 0xFE;
  87         iowrite8(data, hpwdt_timer_con);
  88 }
  89
  90 static int hpwdt_stop_core(struct watchdog_device *wdd)
  91 {
  92         hpwdt_stop();
  93
  94         return 0;
  95 }
  96
  97 static void hpwdt_ping_ticks(int val)
  98 {
  99         val = min(val, HPWDT_MAX_TICKS);
 100         iowrite16(val, hpwdt_timer_reg);
 101 }
 102
 103 static int hpwdt_ping(struct watchdog_device *wdd)
 104 {
 105         int reload = SECS_TO_TICKS(min(wdd->timeout, wdd->max_hw_heartbeat_ms/1000));
 106
 107         dev_dbg(wdd->parent, "ping  watchdog 0x%08x:0x%08x\n", wdd->timeout, reload);
 108         hpwdt_ping_ticks(reload);
 109
 110         return 0;
 111 }
 112
 113 static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd)
 114 {
 115         return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
 116 }
 117
 118 static int hpwdt_settimeout(struct watchdog_device *wdd, unsigned int val)
 119 {
 120         dev_dbg(wdd->parent, "set_timeout = %d\n", val);
 121
 122         wdd->timeout = val;
 123         if (val <= wdd->pretimeout) {
 124                 dev_dbg(wdd->parent, "pretimeout < timeout. Setting to zero\n");
 125                 wdd->pretimeout = 0;
 126                 pretimeout = 0;
 127                 if (watchdog_active(wdd))
 128                         hpwdt_start(wdd);
 129         }
 130         hpwdt_ping(wdd);
 131
 132         return 0;
 133 }
 134
 135 #ifdef CONFIG_HPWDT_NMI_DECODING
 136 static int hpwdt_set_pretimeout(struct watchdog_device *wdd, unsigned int req)
 137 {
 138         unsigned int val = 0;
 139
 140         dev_dbg(wdd->parent, "set_pretimeout = %d\n", req);
 141         if (req) {
 142                 val = PRETIMEOUT_SEC;
 143                 if (val >= wdd->timeout)
 144                         return -EINVAL;
 145         }
 146
 147         if (val != req)
 148                 dev_dbg(wdd->parent, "Rounding pretimeout to: %d\n", val);
 149
 150         wdd->pretimeout = val;
 151         pretimeout = !!val;
 152
 153         if (watchdog_active(wdd))
 154                 hpwdt_start(wdd);
 155
 156         return 0;
 157 }
 158
 159 static int hpwdt_my_nmi(void)
 160 {
 161         return ioread8(hpwdt_nmistat) & 0x6;
 162 }
 163
 164 /*
 165  *      NMI Handler
 166  */
 167 static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
 168 {
 169         unsigned int mynmi = hpwdt_my_nmi();
 170         static char panic_msg[] =
 171                 "00: An NMI occurred. Depending on your system the reason "
 172                 "for the NMI is logged in any one of the following resources:\n"
 173                 "1. Integrated Management Log (IML)\n"
 174                 "2. OA Syslog\n"
 175                 "3. OA Forward Progress Log\n"
 176                 "4. iLO Event Log";
 177
 178         if (ilo5 && ulReason == NMI_UNKNOWN && !mynmi)
 179                 return NMI_DONE;
 180
 181         if (ilo5 && !pretimeout && !mynmi)
 182                 return NMI_DONE;
 183
 184         if (kdumptimeout < 0)
 185                 hpwdt_stop();
 186         else if (kdumptimeout == 0)
 187                 ;
 188         else {
 189                 unsigned int val = max((unsigned int)kdumptimeout, hpwdt_dev.timeout);
 190                 hpwdt_ping_ticks(SECS_TO_TICKS(val));
 191         }
 192
 193         hex_byte_pack(panic_msg, mynmi);
 194         nmi_panic(regs, panic_msg);
 195
 196         return NMI_HANDLED;
 197 }
 198 #endif /* CONFIG_HPWDT_NMI_DECODING */
 199
 200
 201 static const struct watchdog_info ident = {
 202         .options = WDIOF_PRETIMEOUT    |
 203                    WDIOF_SETTIMEOUT    |
 204                    WDIOF_KEEPALIVEPING |
 205                    WDIOF_MAGICCLOSE,
 206         .identity = "HPE iLO2+ HW Watchdog Timer",
 207 };
 208
 209 /*
 210  *      Kernel interfaces
 211  */
 212
 213 static const struct watchdog_ops hpwdt_ops = {
 214         .owner          = THIS_MODULE,
 215         .start          = hpwdt_start,
 216         .stop           = hpwdt_stop_core,
 217         .ping           = hpwdt_ping,
 218         .set_timeout    = hpwdt_settimeout,
 219         .get_timeleft   = hpwdt_gettimeleft,
 220 #ifdef CONFIG_HPWDT_NMI_DECODING
 221         .set_pretimeout = hpwdt_set_pretimeout,
 222 #endif
 223 };
 224
 225 static struct watchdog_device hpwdt_dev = {
 226         .info           = &ident,
 227         .ops            = &hpwdt_ops,
 228         .min_timeout    = 1,
 229         .timeout        = DEFAULT_MARGIN,
 230         .pretimeout     = PRETIMEOUT_SEC,
 231         .max_hw_heartbeat_ms    = HPWDT_MAX_TIMER * 1000,
 232 };
 233
 234
 235 /*
 236  *      Init & Exit
 237  */
 238
 239 static int hpwdt_init_nmi_decoding(struct pci_dev *dev)
 240 {
 241 #ifdef CONFIG_HPWDT_NMI_DECODING
 242         int retval;
 243         /*
 244          * Only one function can register for NMI_UNKNOWN
 245          */
 246         retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt");
 247         if (retval)
 248                 goto error;
 249         retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt");
 250         if (retval)
 251                 goto error1;
 252         retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt");
 253         if (retval)
 254                 goto error2;
 255
 256         dev_info(&dev->dev,
 257                 "HPE Watchdog Timer Driver: NMI decoding initialized\n");
 258
 259         return 0;
 260
 261 error2:
 262         unregister_nmi_handler(NMI_SERR, "hpwdt");
 263 error1:
 264         unregister_nmi_handler(NMI_UNKNOWN, "hpwdt");
 265 error:
 266         dev_warn(&dev->dev,
 267                 "Unable to register a die notifier (err=%d).\n",
 268                 retval);
 269         return retval;
 270 #endif  /* CONFIG_HPWDT_NMI_DECODING */
 271         return 0;
 272 }
 273
 274 static void hpwdt_exit_nmi_decoding(void)
 275 {
 276 #ifdef CONFIG_HPWDT_NMI_DECODING
 277         unregister_nmi_handler(NMI_UNKNOWN, "hpwdt");
 278         unregister_nmi_handler(NMI_SERR, "hpwdt");
 279         unregister_nmi_handler(NMI_IO_CHECK, "hpwdt");
 280 #endif
 281 }
 282
 283 static int hpwdt_init_one(struct pci_dev *dev,
 284                                         const struct pci_device_id *ent)
 285 {
 286         int retval;
 287
 288         /*
 289          * First let's find out if we are on an iLO2+ server. We will
 290          * not run on a legacy ASM box.
 291          * So we only support the G5 ProLiant servers and higher.
 292          */
 293         if (dev->subsystem_vendor != PCI_VENDOR_ID_HP &&
 294             dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) {
 295                 dev_warn(&dev->dev,
 296                         "This server does not have an iLO2+ ASIC.\n");
 297                 return -ENODEV;
 298         }
 299
 300         if (pci_match_id(hpwdt_blacklist, dev)) {
 301                 dev_dbg(&dev->dev, "Not supported on this device\n");
 302                 return -ENODEV;
 303         }
 304
 305         if (pci_enable_device(dev)) {
 306                 dev_warn(&dev->dev,
 307                         "Not possible to enable PCI Device: 0x%x:0x%x.\n",
 308                         ent->vendor, ent->device);
 309                 return -ENODEV;
 310         }
 311
 312         pci_mem_addr = pci_iomap(dev, 1, 0x80);
 313         if (!pci_mem_addr) {
 314                 dev_warn(&dev->dev,
 315                         "Unable to detect the iLO2+ server memory.\n");
 316                 retval = -ENOMEM;
 317                 goto error_pci_iomap;
 318         }
 319         hpwdt_nmistat   = pci_mem_addr + 0x6e;
 320         hpwdt_timer_reg = pci_mem_addr + 0x70;
 321         hpwdt_timer_con = pci_mem_addr + 0x72;
 322
 323         /* Have the core update running timer until user space is ready */
 324         if (hpwdt_hw_is_running()) {
 325                 dev_info(&dev->dev, "timer is running\n");
 326                 set_bit(WDOG_HW_RUNNING, &hpwdt_dev.status);
 327         }
 328
 329         /* Initialize NMI Decoding functionality */
 330         retval = hpwdt_init_nmi_decoding(dev);
 331         if (retval != 0)
 332                 goto error_init_nmi_decoding;
 333
 334         watchdog_stop_on_unregister(&hpwdt_dev);
 335         watchdog_set_nowayout(&hpwdt_dev, nowayout);
 336         watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL);
 337
 338         if (is_kdump_kernel()) {
 339                 pretimeout = 0;
 340                 kdumptimeout = 0;
 341         }
 342
 343         if (pretimeout && hpwdt_dev.timeout <= PRETIMEOUT_SEC) {
 344                 dev_warn(&dev->dev, "timeout <= pretimeout. Setting pretimeout to zero\n");
 345                 pretimeout = 0;
 346         }
 347         hpwdt_dev.pretimeout = pretimeout ? PRETIMEOUT_SEC : 0;
 348         kdumptimeout = min(kdumptimeout, HPWDT_MAX_TIMER);
 349
 350         hpwdt_dev.parent = &dev->dev;
 351         retval = watchdog_register_device(&hpwdt_dev);
 352         if (retval < 0)
 353                 goto error_wd_register;
 354
 355         dev_info(&dev->dev, "HPE Watchdog Timer Driver: Version: %s\n",
 356                                 HPWDT_VERSION);
 357         dev_info(&dev->dev, "timeout: %d seconds (nowayout=%d)\n",
 358                                 hpwdt_dev.timeout, nowayout);
 359         dev_info(&dev->dev, "pretimeout: %s.\n",
 360                                 pretimeout ? "on" : "off");
 361         dev_info(&dev->dev, "kdumptimeout: %d.\n", kdumptimeout);
 362
 363         if (dev->subsystem_vendor == PCI_VENDOR_ID_HP_3PAR)
 364                 ilo5 = true;
 365
 366         return 0;
 367
 368 error_wd_register:
 369         hpwdt_exit_nmi_decoding();
 370 error_init_nmi_decoding:
 371         pci_iounmap(dev, pci_mem_addr);
 372 error_pci_iomap:
 373         pci_disable_device(dev);
 374         return retval;
 375 }
 376
 377 static void hpwdt_exit(struct pci_dev *dev)
 378 {
 379         watchdog_unregister_device(&hpwdt_dev);
 380         hpwdt_exit_nmi_decoding();
 381         pci_iounmap(dev, pci_mem_addr);
 382         pci_disable_device(dev);
 383 }
 384
 385 static struct pci_driver hpwdt_driver = {
 386         .name = "hpwdt",
 387         .id_table = hpwdt_devices,
 388         .probe = hpwdt_init_one,
 389         .remove = hpwdt_exit,
 390 };
 391
 392 MODULE_AUTHOR("Tom Mingarelli");
 393 MODULE_DESCRIPTION("hpe watchdog driver");
 394 MODULE_LICENSE("GPL");
 395 MODULE_VERSION(HPWDT_VERSION);
 396
 397 module_param(soft_margin, int, 0);
 398 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
 399
 400 module_param_named(timeout, soft_margin, int, 0);
 401 MODULE_PARM_DESC(timeout, "Alias of soft_margin");
 402
 403 module_param(nowayout, bool, 0);
 404 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 405                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 406
 407 module_param(kdumptimeout, int, 0444);
 408 MODULE_PARM_DESC(kdumptimeout, "Timeout applied for crash kernel transition in seconds");
 409
 410 #ifdef CONFIG_HPWDT_NMI_DECODING
 411 module_param(pretimeout, bool, 0);
 412 MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled");
 413 #endif
 414
 415 module_pci_driver(hpwdt_driver);