1 /* 2 * HPE WatchDog Driver 3 * based on 4 * 5 * SoftDog 0.05: A Software Watchdog Device 6 * 7 * (c) Copyright 2018 Hewlett Packard Enterprise Development LP 8 * Thomas Mingarelli <thomas.mingarelli@hpe.com> 9 * 10 * This program is free software; you can redistribute it and/or 11 * modify it under the terms of the GNU General Public License 12 * version 2 as published by the Free Software Foundation 13 * 14 */ 15 16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 17 18 #include <linux/device.h> 19 #include <linux/io.h> 20 #include <linux/kernel.h> 21 #include <linux/module.h> 22 #include <linux/moduleparam.h> 23 #include <linux/pci.h> 24 #include <linux/pci_ids.h> 25 #include <linux/types.h> 26 #include <linux/watchdog.h> 27 #include <asm/nmi.h> 28 29 #define HPWDT_VERSION "2.0.2" 30 #define SECS_TO_TICKS(secs) ((secs) * 1000 / 128) 31 #define TICKS_TO_SECS(ticks) ((ticks) * 128 / 1000) 32 #define HPWDT_MAX_TIMER TICKS_TO_SECS(65535) 33 #define DEFAULT_MARGIN 30 34 #define PRETIMEOUT_SEC 9 35 36 static bool ilo5; 37 static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */ 38 static bool nowayout = WATCHDOG_NOWAYOUT; 39 static bool pretimeout = IS_ENABLED(CONFIG_HPWDT_NMI_DECODING); 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 {0}, /* terminate list */ 50 }; 51 MODULE_DEVICE_TABLE(pci, hpwdt_devices); 52 53 static const struct pci_device_id hpwdt_blacklist[] = { 54 { PCI_DEVICE_SUB(PCI_VENDOR_ID_HP, 0x3306, PCI_VENDOR_ID_HP, 0x1979) }, /* auxilary iLO */ 55 { PCI_DEVICE_SUB(PCI_VENDOR_ID_HP, 0x3306, PCI_VENDOR_ID_HP_3PAR, 0x0289) }, /* CL */ 56 {0}, /* terminate list */ 57 }; 58 59 /* 60 * Watchdog operations 61 */ 62 static int hpwdt_start(struct watchdog_device *wdd) 63 { 64 int control = 0x81 | (pretimeout ? 0x4 : 0); 65 int reload = SECS_TO_TICKS(wdd->timeout); 66 67 dev_dbg(wdd->parent, "start watchdog 0x%08x:0x%02x\n", reload, control); 68 iowrite16(reload, hpwdt_timer_reg); 69 iowrite8(control, hpwdt_timer_con); 70 71 return 0; 72 } 73 74 static void hpwdt_stop(void) 75 { 76 unsigned long data; 77 78 pr_debug("stop watchdog\n"); 79 80 data = ioread8(hpwdt_timer_con); 81 data &= 0xFE; 82 iowrite8(data, hpwdt_timer_con); 83 } 84 85 static int hpwdt_stop_core(struct watchdog_device *wdd) 86 { 87 hpwdt_stop(); 88 89 return 0; 90 } 91 92 static int hpwdt_ping(struct watchdog_device *wdd) 93 { 94 int reload = SECS_TO_TICKS(wdd->timeout); 95 96 dev_dbg(wdd->parent, "ping watchdog 0x%08x\n", reload); 97 iowrite16(reload, hpwdt_timer_reg); 98 99 return 0; 100 } 101 102 static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd) 103 { 104 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg)); 105 } 106 107 static int hpwdt_settimeout(struct watchdog_device *wdd, unsigned int val) 108 { 109 dev_dbg(wdd->parent, "set_timeout = %d\n", val); 110 111 wdd->timeout = val; 112 if (val <= wdd->pretimeout) { 113 dev_dbg(wdd->parent, "pretimeout < timeout. Setting to zero\n"); 114 wdd->pretimeout = 0; 115 pretimeout = 0; 116 if (watchdog_active(wdd)) 117 hpwdt_start(wdd); 118 } 119 hpwdt_ping(wdd); 120 121 return 0; 122 } 123 124 #ifdef CONFIG_HPWDT_NMI_DECODING 125 static int hpwdt_set_pretimeout(struct watchdog_device *wdd, unsigned int req) 126 { 127 unsigned int val = 0; 128 129 dev_dbg(wdd->parent, "set_pretimeout = %d\n", req); 130 if (req) { 131 val = PRETIMEOUT_SEC; 132 if (val >= wdd->timeout) 133 return -EINVAL; 134 } 135 136 if (val != req) 137 dev_dbg(wdd->parent, "Rounding pretimeout to: %d\n", val); 138 139 wdd->pretimeout = val; 140 pretimeout = !!val; 141 142 if (watchdog_active(wdd)) 143 hpwdt_start(wdd); 144 145 return 0; 146 } 147 148 static int hpwdt_my_nmi(void) 149 { 150 return ioread8(hpwdt_nmistat) & 0x6; 151 } 152 153 /* 154 * NMI Handler 155 */ 156 static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs) 157 { 158 unsigned int mynmi = hpwdt_my_nmi(); 159 static char panic_msg[] = 160 "00: An NMI occurred. Depending on your system the reason " 161 "for the NMI is logged in any one of the following resources:\n" 162 "1. Integrated Management Log (IML)\n" 163 "2. OA Syslog\n" 164 "3. OA Forward Progress Log\n" 165 "4. iLO Event Log"; 166 167 if (ilo5 && ulReason == NMI_UNKNOWN && !mynmi) 168 return NMI_DONE; 169 170 if (ilo5 && !pretimeout && !mynmi) 171 return NMI_DONE; 172 173 hpwdt_stop(); 174 175 hex_byte_pack(panic_msg, mynmi); 176 nmi_panic(regs, panic_msg); 177 178 return NMI_HANDLED; 179 } 180 #endif /* CONFIG_HPWDT_NMI_DECODING */ 181 182 183 static const struct watchdog_info ident = { 184 .options = WDIOF_PRETIMEOUT | 185 WDIOF_SETTIMEOUT | 186 WDIOF_KEEPALIVEPING | 187 WDIOF_MAGICCLOSE, 188 .identity = "HPE iLO2+ HW Watchdog Timer", 189 }; 190 191 /* 192 * Kernel interfaces 193 */ 194 195 static const struct watchdog_ops hpwdt_ops = { 196 .owner = THIS_MODULE, 197 .start = hpwdt_start, 198 .stop = hpwdt_stop_core, 199 .ping = hpwdt_ping, 200 .set_timeout = hpwdt_settimeout, 201 .get_timeleft = hpwdt_gettimeleft, 202 #ifdef CONFIG_HPWDT_NMI_DECODING 203 .set_pretimeout = hpwdt_set_pretimeout, 204 #endif 205 }; 206 207 static struct watchdog_device hpwdt_dev = { 208 .info = &ident, 209 .ops = &hpwdt_ops, 210 .min_timeout = 1, 211 .max_timeout = HPWDT_MAX_TIMER, 212 .timeout = DEFAULT_MARGIN, 213 .pretimeout = PRETIMEOUT_SEC, 214 }; 215 216 217 /* 218 * Init & Exit 219 */ 220 221 static int hpwdt_init_nmi_decoding(struct pci_dev *dev) 222 { 223 #ifdef CONFIG_HPWDT_NMI_DECODING 224 int retval; 225 /* 226 * Only one function can register for NMI_UNKNOWN 227 */ 228 retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt"); 229 if (retval) 230 goto error; 231 retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt"); 232 if (retval) 233 goto error1; 234 retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt"); 235 if (retval) 236 goto error2; 237 238 dev_info(&dev->dev, 239 "HPE Watchdog Timer Driver: NMI decoding initialized\n"); 240 241 return 0; 242 243 error2: 244 unregister_nmi_handler(NMI_SERR, "hpwdt"); 245 error1: 246 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 247 error: 248 dev_warn(&dev->dev, 249 "Unable to register a die notifier (err=%d).\n", 250 retval); 251 return retval; 252 #endif /* CONFIG_HPWDT_NMI_DECODING */ 253 return 0; 254 } 255 256 static void hpwdt_exit_nmi_decoding(void) 257 { 258 #ifdef CONFIG_HPWDT_NMI_DECODING 259 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 260 unregister_nmi_handler(NMI_SERR, "hpwdt"); 261 unregister_nmi_handler(NMI_IO_CHECK, "hpwdt"); 262 #endif 263 } 264 265 static int hpwdt_init_one(struct pci_dev *dev, 266 const struct pci_device_id *ent) 267 { 268 int retval; 269 270 /* 271 * First let's find out if we are on an iLO2+ server. We will 272 * not run on a legacy ASM box. 273 * So we only support the G5 ProLiant servers and higher. 274 */ 275 if (dev->subsystem_vendor != PCI_VENDOR_ID_HP && 276 dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) { 277 dev_warn(&dev->dev, 278 "This server does not have an iLO2+ ASIC.\n"); 279 return -ENODEV; 280 } 281 282 if (pci_match_id(hpwdt_blacklist, dev)) { 283 dev_dbg(&dev->dev, "Not supported on this device\n"); 284 return -ENODEV; 285 } 286 287 if (pci_enable_device(dev)) { 288 dev_warn(&dev->dev, 289 "Not possible to enable PCI Device: 0x%x:0x%x.\n", 290 ent->vendor, ent->device); 291 return -ENODEV; 292 } 293 294 pci_mem_addr = pci_iomap(dev, 1, 0x80); 295 if (!pci_mem_addr) { 296 dev_warn(&dev->dev, 297 "Unable to detect the iLO2+ server memory.\n"); 298 retval = -ENOMEM; 299 goto error_pci_iomap; 300 } 301 hpwdt_nmistat = pci_mem_addr + 0x6e; 302 hpwdt_timer_reg = pci_mem_addr + 0x70; 303 hpwdt_timer_con = pci_mem_addr + 0x72; 304 305 /* Make sure that timer is disabled until /dev/watchdog is opened */ 306 hpwdt_stop(); 307 308 /* Initialize NMI Decoding functionality */ 309 retval = hpwdt_init_nmi_decoding(dev); 310 if (retval != 0) 311 goto error_init_nmi_decoding; 312 313 watchdog_set_nowayout(&hpwdt_dev, nowayout); 314 if (watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL)) 315 dev_warn(&dev->dev, "Invalid soft_margin: %d.\n", soft_margin); 316 317 if (pretimeout && hpwdt_dev.timeout <= PRETIMEOUT_SEC) { 318 dev_warn(&dev->dev, "timeout <= pretimeout. Setting pretimeout to zero\n"); 319 pretimeout = 0; 320 } 321 hpwdt_dev.pretimeout = pretimeout ? PRETIMEOUT_SEC : 0; 322 323 hpwdt_dev.parent = &dev->dev; 324 retval = watchdog_register_device(&hpwdt_dev); 325 if (retval < 0) { 326 dev_err(&dev->dev, "watchdog register failed: %d.\n", retval); 327 goto error_wd_register; 328 } 329 330 dev_info(&dev->dev, "HPE Watchdog Timer Driver: Version: %s\n", 331 HPWDT_VERSION); 332 dev_info(&dev->dev, "timeout: %d seconds (nowayout=%d)\n", 333 hpwdt_dev.timeout, nowayout); 334 dev_info(&dev->dev, "pretimeout: %s.\n", 335 pretimeout ? "on" : "off"); 336 337 if (dev->subsystem_vendor == PCI_VENDOR_ID_HP_3PAR) 338 ilo5 = true; 339 340 return 0; 341 342 error_wd_register: 343 hpwdt_exit_nmi_decoding(); 344 error_init_nmi_decoding: 345 pci_iounmap(dev, pci_mem_addr); 346 error_pci_iomap: 347 pci_disable_device(dev); 348 return retval; 349 } 350 351 static void hpwdt_exit(struct pci_dev *dev) 352 { 353 if (!nowayout) 354 hpwdt_stop(); 355 356 watchdog_unregister_device(&hpwdt_dev); 357 hpwdt_exit_nmi_decoding(); 358 pci_iounmap(dev, pci_mem_addr); 359 pci_disable_device(dev); 360 } 361 362 static struct pci_driver hpwdt_driver = { 363 .name = "hpwdt", 364 .id_table = hpwdt_devices, 365 .probe = hpwdt_init_one, 366 .remove = hpwdt_exit, 367 }; 368 369 MODULE_AUTHOR("Tom Mingarelli"); 370 MODULE_DESCRIPTION("hpe watchdog driver"); 371 MODULE_LICENSE("GPL"); 372 MODULE_VERSION(HPWDT_VERSION); 373 374 module_param(soft_margin, int, 0); 375 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); 376 377 module_param_named(timeout, soft_margin, int, 0); 378 MODULE_PARM_DESC(timeout, "Alias of soft_margin"); 379 380 module_param(nowayout, bool, 0); 381 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 382 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 383 384 #ifdef CONFIG_HPWDT_NMI_DECODING 385 module_param(pretimeout, bool, 0); 386 MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled"); 387 #endif 388 389 module_pci_driver(hpwdt_driver); 390