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 "2.0.1" 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 54 /* 55 * Watchdog operations 56 */ 57 static int hpwdt_start(struct watchdog_device *wdd) 58 { 59 int control = 0x81 | (pretimeout ? 0x4 : 0); 60 int reload = SECS_TO_TICKS(wdd->timeout); 61 62 dev_dbg(wdd->parent, "start watchdog 0x%08x:0x%02x\n", reload, control); 63 iowrite16(reload, hpwdt_timer_reg); 64 iowrite8(control, hpwdt_timer_con); 65 66 return 0; 67 } 68 69 static void hpwdt_stop(void) 70 { 71 unsigned long data; 72 73 pr_debug("stop watchdog\n"); 74 75 data = ioread8(hpwdt_timer_con); 76 data &= 0xFE; 77 iowrite8(data, hpwdt_timer_con); 78 } 79 80 static int hpwdt_stop_core(struct watchdog_device *wdd) 81 { 82 hpwdt_stop(); 83 84 return 0; 85 } 86 87 static int hpwdt_ping(struct watchdog_device *wdd) 88 { 89 int reload = SECS_TO_TICKS(wdd->timeout); 90 91 dev_dbg(wdd->parent, "ping watchdog 0x%08x\n", reload); 92 iowrite16(reload, hpwdt_timer_reg); 93 94 return 0; 95 } 96 97 static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd) 98 { 99 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg)); 100 } 101 102 static int hpwdt_settimeout(struct watchdog_device *wdd, unsigned int val) 103 { 104 dev_dbg(wdd->parent, "set_timeout = %d\n", val); 105 106 wdd->timeout = val; 107 if (val <= wdd->pretimeout) { 108 dev_dbg(wdd->parent, "pretimeout < timeout. Setting to zero\n"); 109 wdd->pretimeout = 0; 110 pretimeout = 0; 111 if (watchdog_active(wdd)) 112 hpwdt_start(wdd); 113 } 114 hpwdt_ping(wdd); 115 116 return 0; 117 } 118 119 #ifdef CONFIG_HPWDT_NMI_DECODING 120 static int hpwdt_set_pretimeout(struct watchdog_device *wdd, unsigned int req) 121 { 122 unsigned int val = 0; 123 124 dev_dbg(wdd->parent, "set_pretimeout = %d\n", req); 125 if (req) { 126 val = PRETIMEOUT_SEC; 127 if (val >= wdd->timeout) 128 return -EINVAL; 129 } 130 131 if (val != req) 132 dev_dbg(wdd->parent, "Rounding pretimeout to: %d\n", val); 133 134 wdd->pretimeout = val; 135 pretimeout = !!val; 136 137 if (watchdog_active(wdd)) 138 hpwdt_start(wdd); 139 140 return 0; 141 } 142 143 static int hpwdt_my_nmi(void) 144 { 145 return ioread8(hpwdt_nmistat) & 0x6; 146 } 147 148 /* 149 * NMI Handler 150 */ 151 static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs) 152 { 153 unsigned int mynmi = hpwdt_my_nmi(); 154 static char panic_msg[] = 155 "00: An NMI occurred. Depending on your system the reason " 156 "for the NMI is logged in any one of the following resources:\n" 157 "1. Integrated Management Log (IML)\n" 158 "2. OA Syslog\n" 159 "3. OA Forward Progress Log\n" 160 "4. iLO Event Log"; 161 162 if (ilo5 && ulReason == NMI_UNKNOWN && !mynmi) 163 return NMI_DONE; 164 165 if (ilo5 && !pretimeout && !mynmi) 166 return NMI_DONE; 167 168 hpwdt_stop(); 169 170 hex_byte_pack(panic_msg, mynmi); 171 nmi_panic(regs, panic_msg); 172 173 return NMI_HANDLED; 174 } 175 #endif /* CONFIG_HPWDT_NMI_DECODING */ 176 177 178 static const struct watchdog_info ident = { 179 .options = WDIOF_PRETIMEOUT | 180 WDIOF_SETTIMEOUT | 181 WDIOF_KEEPALIVEPING | 182 WDIOF_MAGICCLOSE, 183 .identity = "HPE iLO2+ HW Watchdog Timer", 184 }; 185 186 /* 187 * Kernel interfaces 188 */ 189 190 static const struct watchdog_ops hpwdt_ops = { 191 .owner = THIS_MODULE, 192 .start = hpwdt_start, 193 .stop = hpwdt_stop_core, 194 .ping = hpwdt_ping, 195 .set_timeout = hpwdt_settimeout, 196 .get_timeleft = hpwdt_gettimeleft, 197 #ifdef CONFIG_HPWDT_NMI_DECODING 198 .set_pretimeout = hpwdt_set_pretimeout, 199 #endif 200 }; 201 202 static struct watchdog_device hpwdt_dev = { 203 .info = &ident, 204 .ops = &hpwdt_ops, 205 .min_timeout = 1, 206 .max_timeout = HPWDT_MAX_TIMER, 207 .timeout = DEFAULT_MARGIN, 208 .pretimeout = PRETIMEOUT_SEC, 209 }; 210 211 212 /* 213 * Init & Exit 214 */ 215 216 static int hpwdt_init_nmi_decoding(struct pci_dev *dev) 217 { 218 #ifdef CONFIG_HPWDT_NMI_DECODING 219 int retval; 220 /* 221 * Only one function can register for NMI_UNKNOWN 222 */ 223 retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt"); 224 if (retval) 225 goto error; 226 retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt"); 227 if (retval) 228 goto error1; 229 retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt"); 230 if (retval) 231 goto error2; 232 233 dev_info(&dev->dev, 234 "HPE Watchdog Timer Driver: NMI decoding initialized\n"); 235 236 return 0; 237 238 error2: 239 unregister_nmi_handler(NMI_SERR, "hpwdt"); 240 error1: 241 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 242 error: 243 dev_warn(&dev->dev, 244 "Unable to register a die notifier (err=%d).\n", 245 retval); 246 return retval; 247 #endif /* CONFIG_HPWDT_NMI_DECODING */ 248 return 0; 249 } 250 251 static void hpwdt_exit_nmi_decoding(void) 252 { 253 #ifdef CONFIG_HPWDT_NMI_DECODING 254 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 255 unregister_nmi_handler(NMI_SERR, "hpwdt"); 256 unregister_nmi_handler(NMI_IO_CHECK, "hpwdt"); 257 #endif 258 } 259 260 static int hpwdt_init_one(struct pci_dev *dev, 261 const struct pci_device_id *ent) 262 { 263 int retval; 264 265 /* 266 * First let's find out if we are on an iLO2+ server. We will 267 * not run on a legacy ASM box. 268 * So we only support the G5 ProLiant servers and higher. 269 */ 270 if (dev->subsystem_vendor != PCI_VENDOR_ID_HP && 271 dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) { 272 dev_warn(&dev->dev, 273 "This server does not have an iLO2+ ASIC.\n"); 274 return -ENODEV; 275 } 276 277 /* 278 * Ignore all auxilary iLO devices with the following PCI ID 279 */ 280 if (dev->subsystem_vendor == PCI_VENDOR_ID_HP && 281 dev->subsystem_device == 0x1979) 282 return -ENODEV; 283 284 if (pci_enable_device(dev)) { 285 dev_warn(&dev->dev, 286 "Not possible to enable PCI Device: 0x%x:0x%x.\n", 287 ent->vendor, ent->device); 288 return -ENODEV; 289 } 290 291 pci_mem_addr = pci_iomap(dev, 1, 0x80); 292 if (!pci_mem_addr) { 293 dev_warn(&dev->dev, 294 "Unable to detect the iLO2+ server memory.\n"); 295 retval = -ENOMEM; 296 goto error_pci_iomap; 297 } 298 hpwdt_nmistat = pci_mem_addr + 0x6e; 299 hpwdt_timer_reg = pci_mem_addr + 0x70; 300 hpwdt_timer_con = pci_mem_addr + 0x72; 301 302 /* Make sure that timer is disabled until /dev/watchdog is opened */ 303 hpwdt_stop(); 304 305 /* Initialize NMI Decoding functionality */ 306 retval = hpwdt_init_nmi_decoding(dev); 307 if (retval != 0) 308 goto error_init_nmi_decoding; 309 310 watchdog_set_nowayout(&hpwdt_dev, nowayout); 311 if (watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL)) 312 dev_warn(&dev->dev, "Invalid soft_margin: %d.\n", soft_margin); 313 314 if (pretimeout && hpwdt_dev.timeout <= PRETIMEOUT_SEC) { 315 dev_warn(&dev->dev, "timeout <= pretimeout. Setting pretimeout to zero\n"); 316 pretimeout = 0; 317 } 318 hpwdt_dev.pretimeout = pretimeout ? PRETIMEOUT_SEC : 0; 319 320 hpwdt_dev.parent = &dev->dev; 321 retval = watchdog_register_device(&hpwdt_dev); 322 if (retval < 0) { 323 dev_err(&dev->dev, "watchdog register failed: %d.\n", retval); 324 goto error_wd_register; 325 } 326 327 dev_info(&dev->dev, "HPE Watchdog Timer Driver: Version: %s\n", 328 HPWDT_VERSION); 329 dev_info(&dev->dev, "timeout: %d seconds (nowayout=%d)\n", 330 hpwdt_dev.timeout, nowayout); 331 dev_info(&dev->dev, "pretimeout: %s.\n", 332 pretimeout ? "on" : "off"); 333 334 if (dev->subsystem_vendor == PCI_VENDOR_ID_HP_3PAR) 335 ilo5 = true; 336 337 return 0; 338 339 error_wd_register: 340 hpwdt_exit_nmi_decoding(); 341 error_init_nmi_decoding: 342 pci_iounmap(dev, pci_mem_addr); 343 error_pci_iomap: 344 pci_disable_device(dev); 345 return retval; 346 } 347 348 static void hpwdt_exit(struct pci_dev *dev) 349 { 350 if (!nowayout) 351 hpwdt_stop(); 352 353 watchdog_unregister_device(&hpwdt_dev); 354 hpwdt_exit_nmi_decoding(); 355 pci_iounmap(dev, pci_mem_addr); 356 pci_disable_device(dev); 357 } 358 359 static struct pci_driver hpwdt_driver = { 360 .name = "hpwdt", 361 .id_table = hpwdt_devices, 362 .probe = hpwdt_init_one, 363 .remove = hpwdt_exit, 364 }; 365 366 MODULE_AUTHOR("Tom Mingarelli"); 367 MODULE_DESCRIPTION("hpe watchdog driver"); 368 MODULE_LICENSE("GPL"); 369 MODULE_VERSION(HPWDT_VERSION); 370 371 module_param(soft_margin, int, 0); 372 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); 373 374 module_param_named(timeout, soft_margin, int, 0); 375 MODULE_PARM_DESC(timeout, "Alias of soft_margin"); 376 377 module_param(nowayout, bool, 0); 378 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 379 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 380 381 #ifdef CONFIG_HPWDT_NMI_DECODING 382 module_param(pretimeout, bool, 0); 383 MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled"); 384 #endif 385 386 module_pci_driver(hpwdt_driver); 387