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 #ifdef CONFIG_HPWDT_NMI_DECODING 24 #include <asm/nmi.h> 25 #endif 26 #include <linux/crash_dump.h> 27 28 #define HPWDT_VERSION "2.0.4" 29 #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128) 30 #define TICKS_TO_SECS(ticks) ((ticks) * 128 / 1000) 31 #define HPWDT_MAX_TICKS 65535 32 #define HPWDT_MAX_TIMER TICKS_TO_SECS(HPWDT_MAX_TICKS) 33 #define DEFAULT_MARGIN 30 34 #define PRETIMEOUT_SEC 9 35 36 static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */ 37 static bool nowayout = WATCHDOG_NOWAYOUT; 38 static bool pretimeout = IS_ENABLED(CONFIG_HPWDT_NMI_DECODING); 39 static int kdumptimeout = -1; 40 41 static void __iomem *pci_mem_addr; /* the PCI-memory address */ 42 static unsigned long __iomem *hpwdt_nmistat; 43 static unsigned long __iomem *hpwdt_timer_reg; 44 static unsigned long __iomem *hpwdt_timer_con; 45 46 static const struct pci_device_id hpwdt_devices[] = { 47 { PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB203) }, /* iLO2 */ 48 { PCI_DEVICE(PCI_VENDOR_ID_HP, 0x3306) }, /* iLO3 */ 49 { PCI_DEVICE(PCI_VENDOR_ID_HP_3PAR, 0x0389) }, /* PCtrl */ 50 {0}, /* terminate list */ 51 }; 52 MODULE_DEVICE_TABLE(pci, hpwdt_devices); 53 54 static const struct pci_device_id hpwdt_blacklist[] = { 55 { PCI_DEVICE_SUB(PCI_VENDOR_ID_HP, 0x3306, PCI_VENDOR_ID_HP, 0x1979) }, /* auxilary iLO */ 56 { PCI_DEVICE_SUB(PCI_VENDOR_ID_HP, 0x3306, PCI_VENDOR_ID_HP_3PAR, 0x0289) }, /* CL */ 57 {0}, /* terminate list */ 58 }; 59 60 static struct watchdog_device hpwdt_dev; 61 /* 62 * Watchdog operations 63 */ 64 static int hpwdt_hw_is_running(void) 65 { 66 return ioread8(hpwdt_timer_con) & 0x01; 67 } 68 69 static int hpwdt_start(struct watchdog_device *wdd) 70 { 71 int control = 0x81 | (pretimeout ? 0x4 : 0); 72 int reload = SECS_TO_TICKS(min(wdd->timeout, wdd->max_hw_heartbeat_ms/1000)); 73 74 dev_dbg(wdd->parent, "start watchdog 0x%08x:0x%08x:0x%02x\n", wdd->timeout, reload, control); 75 iowrite16(reload, hpwdt_timer_reg); 76 iowrite8(control, hpwdt_timer_con); 77 78 return 0; 79 } 80 81 static void hpwdt_stop(void) 82 { 83 unsigned long data; 84 85 pr_debug("stop watchdog\n"); 86 87 data = ioread8(hpwdt_timer_con); 88 data &= 0xFE; 89 iowrite8(data, hpwdt_timer_con); 90 } 91 92 static int hpwdt_stop_core(struct watchdog_device *wdd) 93 { 94 hpwdt_stop(); 95 96 return 0; 97 } 98 99 static void hpwdt_ping_ticks(int val) 100 { 101 val = min(val, HPWDT_MAX_TICKS); 102 iowrite16(val, hpwdt_timer_reg); 103 } 104 105 static int hpwdt_ping(struct watchdog_device *wdd) 106 { 107 int reload = SECS_TO_TICKS(min(wdd->timeout, wdd->max_hw_heartbeat_ms/1000)); 108 109 dev_dbg(wdd->parent, "ping watchdog 0x%08x:0x%08x\n", wdd->timeout, reload); 110 hpwdt_ping_ticks(reload); 111 112 return 0; 113 } 114 115 static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd) 116 { 117 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg)); 118 } 119 120 static int hpwdt_settimeout(struct watchdog_device *wdd, unsigned int val) 121 { 122 dev_dbg(wdd->parent, "set_timeout = %d\n", val); 123 124 wdd->timeout = val; 125 if (val <= wdd->pretimeout) { 126 dev_dbg(wdd->parent, "pretimeout < timeout. Setting to zero\n"); 127 wdd->pretimeout = 0; 128 pretimeout = false; 129 if (watchdog_active(wdd)) 130 hpwdt_start(wdd); 131 } 132 hpwdt_ping(wdd); 133 134 return 0; 135 } 136 137 #ifdef CONFIG_HPWDT_NMI_DECODING 138 static int hpwdt_set_pretimeout(struct watchdog_device *wdd, unsigned int req) 139 { 140 unsigned int val = 0; 141 142 dev_dbg(wdd->parent, "set_pretimeout = %d\n", req); 143 if (req) { 144 val = PRETIMEOUT_SEC; 145 if (val >= wdd->timeout) 146 return -EINVAL; 147 } 148 149 if (val != req) 150 dev_dbg(wdd->parent, "Rounding pretimeout to: %d\n", val); 151 152 wdd->pretimeout = val; 153 pretimeout = !!val; 154 155 if (watchdog_active(wdd)) 156 hpwdt_start(wdd); 157 158 return 0; 159 } 160 161 static int hpwdt_my_nmi(void) 162 { 163 return ioread8(hpwdt_nmistat) & 0x6; 164 } 165 166 /* 167 * NMI Handler 168 */ 169 static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs) 170 { 171 unsigned int mynmi = hpwdt_my_nmi(); 172 static char panic_msg[] = 173 "00: An NMI occurred. Depending on your system the reason " 174 "for the NMI is logged in any one of the following resources:\n" 175 "1. Integrated Management Log (IML)\n" 176 "2. OA Syslog\n" 177 "3. OA Forward Progress Log\n" 178 "4. iLO Event Log"; 179 180 if (ulReason == NMI_UNKNOWN && !mynmi) 181 return NMI_DONE; 182 183 if (kdumptimeout < 0) 184 hpwdt_stop(); 185 else if (kdumptimeout == 0) 186 ; 187 else { 188 unsigned int val = max((unsigned int)kdumptimeout, hpwdt_dev.timeout); 189 hpwdt_ping_ticks(SECS_TO_TICKS(val)); 190 } 191 192 hex_byte_pack(panic_msg, mynmi); 193 nmi_panic(regs, panic_msg); 194 195 return NMI_HANDLED; 196 } 197 #endif /* CONFIG_HPWDT_NMI_DECODING */ 198 199 200 static const struct watchdog_info ident = { 201 .options = WDIOF_PRETIMEOUT | 202 WDIOF_SETTIMEOUT | 203 WDIOF_KEEPALIVEPING | 204 WDIOF_MAGICCLOSE, 205 .identity = "HPE iLO2+ HW Watchdog Timer", 206 }; 207 208 /* 209 * Kernel interfaces 210 */ 211 212 static const struct watchdog_ops hpwdt_ops = { 213 .owner = THIS_MODULE, 214 .start = hpwdt_start, 215 .stop = hpwdt_stop_core, 216 .ping = hpwdt_ping, 217 .set_timeout = hpwdt_settimeout, 218 .get_timeleft = hpwdt_gettimeleft, 219 #ifdef CONFIG_HPWDT_NMI_DECODING 220 .set_pretimeout = hpwdt_set_pretimeout, 221 #endif 222 }; 223 224 static struct watchdog_device hpwdt_dev = { 225 .info = &ident, 226 .ops = &hpwdt_ops, 227 .min_timeout = 1, 228 .timeout = DEFAULT_MARGIN, 229 .pretimeout = PRETIMEOUT_SEC, 230 .max_hw_heartbeat_ms = HPWDT_MAX_TIMER * 1000, 231 }; 232 233 234 /* 235 * Init & Exit 236 */ 237 238 static int hpwdt_init_nmi_decoding(struct pci_dev *dev) 239 { 240 #ifdef CONFIG_HPWDT_NMI_DECODING 241 int retval; 242 /* 243 * Only one function can register for NMI_UNKNOWN 244 */ 245 retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt"); 246 if (retval) 247 goto error; 248 retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt"); 249 if (retval) 250 goto error1; 251 retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt"); 252 if (retval) 253 goto error2; 254 255 dev_info(&dev->dev, 256 "HPE Watchdog Timer Driver: NMI decoding initialized\n"); 257 258 return 0; 259 260 error2: 261 unregister_nmi_handler(NMI_SERR, "hpwdt"); 262 error1: 263 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 264 error: 265 dev_warn(&dev->dev, 266 "Unable to register a die notifier (err=%d).\n", 267 retval); 268 return retval; 269 #endif /* CONFIG_HPWDT_NMI_DECODING */ 270 return 0; 271 } 272 273 static void hpwdt_exit_nmi_decoding(void) 274 { 275 #ifdef CONFIG_HPWDT_NMI_DECODING 276 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 277 unregister_nmi_handler(NMI_SERR, "hpwdt"); 278 unregister_nmi_handler(NMI_IO_CHECK, "hpwdt"); 279 #endif 280 } 281 282 static int hpwdt_init_one(struct pci_dev *dev, 283 const struct pci_device_id *ent) 284 { 285 int retval; 286 287 /* 288 * First let's find out if we are on an iLO2+ server. We will 289 * not run on a legacy ASM box. 290 * So we only support the G5 ProLiant servers and higher. 291 */ 292 if (dev->subsystem_vendor != PCI_VENDOR_ID_HP && 293 dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) { 294 dev_warn(&dev->dev, 295 "This server does not have an iLO2+ ASIC.\n"); 296 return -ENODEV; 297 } 298 299 if (pci_match_id(hpwdt_blacklist, dev)) { 300 dev_dbg(&dev->dev, "Not supported on this device\n"); 301 return -ENODEV; 302 } 303 304 if (pci_enable_device(dev)) { 305 dev_warn(&dev->dev, 306 "Not possible to enable PCI Device: 0x%x:0x%x.\n", 307 ent->vendor, ent->device); 308 return -ENODEV; 309 } 310 311 pci_mem_addr = pci_iomap(dev, 1, 0x80); 312 if (!pci_mem_addr) { 313 dev_warn(&dev->dev, 314 "Unable to detect the iLO2+ server memory.\n"); 315 retval = -ENOMEM; 316 goto error_pci_iomap; 317 } 318 hpwdt_nmistat = pci_mem_addr + 0x6e; 319 hpwdt_timer_reg = pci_mem_addr + 0x70; 320 hpwdt_timer_con = pci_mem_addr + 0x72; 321 322 /* Have the core update running timer until user space is ready */ 323 if (hpwdt_hw_is_running()) { 324 dev_info(&dev->dev, "timer is running\n"); 325 set_bit(WDOG_HW_RUNNING, &hpwdt_dev.status); 326 } 327 328 /* Initialize NMI Decoding functionality */ 329 retval = hpwdt_init_nmi_decoding(dev); 330 if (retval != 0) 331 goto error_init_nmi_decoding; 332 333 watchdog_stop_on_unregister(&hpwdt_dev); 334 watchdog_set_nowayout(&hpwdt_dev, nowayout); 335 watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL); 336 337 if (is_kdump_kernel()) { 338 pretimeout = false; 339 kdumptimeout = 0; 340 } 341 342 if (pretimeout && hpwdt_dev.timeout <= PRETIMEOUT_SEC) { 343 dev_warn(&dev->dev, "timeout <= pretimeout. Setting pretimeout to zero\n"); 344 pretimeout = false; 345 } 346 hpwdt_dev.pretimeout = pretimeout ? PRETIMEOUT_SEC : 0; 347 kdumptimeout = min(kdumptimeout, HPWDT_MAX_TIMER); 348 349 hpwdt_dev.parent = &dev->dev; 350 retval = watchdog_register_device(&hpwdt_dev); 351 if (retval < 0) 352 goto error_wd_register; 353 354 dev_info(&dev->dev, "HPE Watchdog Timer Driver: Version: %s\n", 355 HPWDT_VERSION); 356 dev_info(&dev->dev, "timeout: %d seconds (nowayout=%d)\n", 357 hpwdt_dev.timeout, nowayout); 358 dev_info(&dev->dev, "pretimeout: %s.\n", 359 pretimeout ? "on" : "off"); 360 dev_info(&dev->dev, "kdumptimeout: %d.\n", kdumptimeout); 361 362 return 0; 363 364 error_wd_register: 365 hpwdt_exit_nmi_decoding(); 366 error_init_nmi_decoding: 367 pci_iounmap(dev, pci_mem_addr); 368 error_pci_iomap: 369 pci_disable_device(dev); 370 return retval; 371 } 372 373 static void hpwdt_exit(struct pci_dev *dev) 374 { 375 watchdog_unregister_device(&hpwdt_dev); 376 hpwdt_exit_nmi_decoding(); 377 pci_iounmap(dev, pci_mem_addr); 378 pci_disable_device(dev); 379 } 380 381 static struct pci_driver hpwdt_driver = { 382 .name = "hpwdt", 383 .id_table = hpwdt_devices, 384 .probe = hpwdt_init_one, 385 .remove = hpwdt_exit, 386 }; 387 388 MODULE_AUTHOR("Tom Mingarelli"); 389 MODULE_DESCRIPTION("hpe watchdog driver"); 390 MODULE_LICENSE("GPL"); 391 MODULE_VERSION(HPWDT_VERSION); 392 393 module_param(soft_margin, int, 0); 394 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); 395 396 module_param_named(timeout, soft_margin, int, 0); 397 MODULE_PARM_DESC(timeout, "Alias of soft_margin"); 398 399 module_param(nowayout, bool, 0); 400 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 401 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 402 403 module_param(kdumptimeout, int, 0444); 404 MODULE_PARM_DESC(kdumptimeout, "Timeout applied for crash kernel transition in seconds"); 405 406 #ifdef CONFIG_HPWDT_NMI_DECODING 407 module_param(pretimeout, bool, 0); 408 MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled"); 409 #endif 410 411 module_pci_driver(hpwdt_driver); 412