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 "2.0.0" 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) 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 #ifdef CONFIG_HPWDT_NMI_DECODING 209 .pretimeout = PRETIMEOUT_SEC, 210 #endif 211 }; 212 213 214 /* 215 * Init & Exit 216 */ 217 218 static int hpwdt_init_nmi_decoding(struct pci_dev *dev) 219 { 220 #ifdef CONFIG_HPWDT_NMI_DECODING 221 int retval; 222 /* 223 * Only one function can register for NMI_UNKNOWN 224 */ 225 retval = register_nmi_handler(NMI_UNKNOWN, hpwdt_pretimeout, 0, "hpwdt"); 226 if (retval) 227 goto error; 228 retval = register_nmi_handler(NMI_SERR, hpwdt_pretimeout, 0, "hpwdt"); 229 if (retval) 230 goto error1; 231 retval = register_nmi_handler(NMI_IO_CHECK, hpwdt_pretimeout, 0, "hpwdt"); 232 if (retval) 233 goto error2; 234 235 dev_info(&dev->dev, 236 "HPE Watchdog Timer Driver: NMI decoding initialized\n"); 237 238 return 0; 239 240 error2: 241 unregister_nmi_handler(NMI_SERR, "hpwdt"); 242 error1: 243 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 244 error: 245 dev_warn(&dev->dev, 246 "Unable to register a die notifier (err=%d).\n", 247 retval); 248 return retval; 249 #endif /* CONFIG_HPWDT_NMI_DECODING */ 250 return 0; 251 } 252 253 static void hpwdt_exit_nmi_decoding(void) 254 { 255 #ifdef CONFIG_HPWDT_NMI_DECODING 256 unregister_nmi_handler(NMI_UNKNOWN, "hpwdt"); 257 unregister_nmi_handler(NMI_SERR, "hpwdt"); 258 unregister_nmi_handler(NMI_IO_CHECK, "hpwdt"); 259 #endif 260 } 261 262 static int hpwdt_init_one(struct pci_dev *dev, 263 const struct pci_device_id *ent) 264 { 265 int retval; 266 267 /* 268 * First let's find out if we are on an iLO2+ server. We will 269 * not run on a legacy ASM box. 270 * So we only support the G5 ProLiant servers and higher. 271 */ 272 if (dev->subsystem_vendor != PCI_VENDOR_ID_HP && 273 dev->subsystem_vendor != PCI_VENDOR_ID_HP_3PAR) { 274 dev_warn(&dev->dev, 275 "This server does not have an iLO2+ ASIC.\n"); 276 return -ENODEV; 277 } 278 279 /* 280 * Ignore all auxilary iLO devices with the following PCI ID 281 */ 282 if (dev->subsystem_vendor == PCI_VENDOR_ID_HP && 283 dev->subsystem_device == 0x1979) 284 return -ENODEV; 285 286 if (pci_enable_device(dev)) { 287 dev_warn(&dev->dev, 288 "Not possible to enable PCI Device: 0x%x:0x%x.\n", 289 ent->vendor, ent->device); 290 return -ENODEV; 291 } 292 293 pci_mem_addr = pci_iomap(dev, 1, 0x80); 294 if (!pci_mem_addr) { 295 dev_warn(&dev->dev, 296 "Unable to detect the iLO2+ server memory.\n"); 297 retval = -ENOMEM; 298 goto error_pci_iomap; 299 } 300 hpwdt_nmistat = pci_mem_addr + 0x6e; 301 hpwdt_timer_reg = pci_mem_addr + 0x70; 302 hpwdt_timer_con = pci_mem_addr + 0x72; 303 304 /* Make sure that timer is disabled until /dev/watchdog is opened */ 305 hpwdt_stop(); 306 307 /* Initialize NMI Decoding functionality */ 308 retval = hpwdt_init_nmi_decoding(dev); 309 if (retval != 0) 310 goto error_init_nmi_decoding; 311 312 watchdog_set_nowayout(&hpwdt_dev, nowayout); 313 if (watchdog_init_timeout(&hpwdt_dev, soft_margin, NULL)) 314 dev_warn(&dev->dev, "Invalid soft_margin: %d.\n", soft_margin); 315 316 hpwdt_dev.parent = &dev->dev; 317 retval = watchdog_register_device(&hpwdt_dev); 318 if (retval < 0) { 319 dev_err(&dev->dev, "watchdog register failed: %d.\n", retval); 320 goto error_wd_register; 321 } 322 323 dev_info(&dev->dev, "HPE Watchdog Timer Driver: %s" 324 ", timer margin: %d seconds (nowayout=%d).\n", 325 HPWDT_VERSION, hpwdt_dev.timeout, nowayout); 326 327 if (dev->subsystem_vendor == PCI_VENDOR_ID_HP_3PAR) 328 ilo5 = true; 329 330 return 0; 331 332 error_wd_register: 333 hpwdt_exit_nmi_decoding(); 334 error_init_nmi_decoding: 335 pci_iounmap(dev, pci_mem_addr); 336 error_pci_iomap: 337 pci_disable_device(dev); 338 return retval; 339 } 340 341 static void hpwdt_exit(struct pci_dev *dev) 342 { 343 if (!nowayout) 344 hpwdt_stop(); 345 346 watchdog_unregister_device(&hpwdt_dev); 347 hpwdt_exit_nmi_decoding(); 348 pci_iounmap(dev, pci_mem_addr); 349 pci_disable_device(dev); 350 } 351 352 static struct pci_driver hpwdt_driver = { 353 .name = "hpwdt", 354 .id_table = hpwdt_devices, 355 .probe = hpwdt_init_one, 356 .remove = hpwdt_exit, 357 }; 358 359 MODULE_AUTHOR("Tom Mingarelli"); 360 MODULE_DESCRIPTION("hpe watchdog driver"); 361 MODULE_LICENSE("GPL"); 362 MODULE_VERSION(HPWDT_VERSION); 363 364 module_param(soft_margin, int, 0); 365 MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds"); 366 367 module_param(nowayout, bool, 0); 368 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" 369 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 370 371 #ifdef CONFIG_HPWDT_NMI_DECODING 372 module_param(pretimeout, bool, 0); 373 MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled"); 374 #endif 375 376 module_pci_driver(hpwdt_driver); 377