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 */
hpwdt_start(struct watchdog_device * wdd)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
hpwdt_stop(void)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
hpwdt_stop_core(struct watchdog_device * wdd)80 static int hpwdt_stop_core(struct watchdog_device *wdd)
81 {
82 hpwdt_stop();
83
84 return 0;
85 }
86
hpwdt_ping(struct watchdog_device * wdd)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
hpwdt_gettimeleft(struct watchdog_device * wdd)97 static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd)
98 {
99 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
100 }
101
hpwdt_settimeout(struct watchdog_device * wdd,unsigned int val)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
hpwdt_set_pretimeout(struct watchdog_device * wdd,unsigned int req)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
hpwdt_my_nmi(void)143 static int hpwdt_my_nmi(void)
144 {
145 return ioread8(hpwdt_nmistat) & 0x6;
146 }
147
148 /*
149 * NMI Handler
150 */
hpwdt_pretimeout(unsigned int ulReason,struct pt_regs * regs)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
hpwdt_init_nmi_decoding(struct pci_dev * dev)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
hpwdt_exit_nmi_decoding(void)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
hpwdt_init_one(struct pci_dev * dev,const struct pci_device_id * ent)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
hpwdt_exit(struct pci_dev * dev)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
