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
36static unsigned int soft_margin = DEFAULT_MARGIN; /* in seconds */
37static bool nowayout = WATCHDOG_NOWAYOUT;
38static bool pretimeout = IS_ENABLED(CONFIG_HPWDT_NMI_DECODING);
39static int kdumptimeout = -1;
40
41static void __iomem *pci_mem_addr; /* the PCI-memory address */
42static unsigned long __iomem *hpwdt_nmistat;
43static unsigned long __iomem *hpwdt_timer_reg;
44static unsigned long __iomem *hpwdt_timer_con;
45
46static 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};
52MODULE_DEVICE_TABLE(pci, hpwdt_devices);
53
54static 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
60static struct watchdog_device hpwdt_dev;
61/*
62 * Watchdog operations
63 */
64static int hpwdt_hw_is_running(void)
65{
66 return ioread8(hpwdt_timer_con) & 0x01;
67}
68
69static 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
81static 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
92static int hpwdt_stop_core(struct watchdog_device *wdd)
93{
94 hpwdt_stop();
95
96 return 0;
97}
98
99static void hpwdt_ping_ticks(int val)
100{
101 val = min(val, HPWDT_MAX_TICKS);
102 iowrite16(val, hpwdt_timer_reg);
103}
104
105static 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(val: reload);
111
112 return 0;
113}
114
115static unsigned int hpwdt_gettimeleft(struct watchdog_device *wdd)
116{
117 return TICKS_TO_SECS(ioread16(hpwdt_timer_reg));
118}
119
120static 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
138static 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
161static int hpwdt_my_nmi(void)
162{
163 return ioread8(hpwdt_nmistat) & 0x6;
164}
165
166/*
167 * NMI Handler
168 */
169static 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(buf: panic_msg, byte: mynmi);
193 nmi_panic(regs, msg: panic_msg);
194
195 return NMI_HANDLED;
196}
197#endif /* CONFIG_HPWDT_NMI_DECODING */
198
199
200static 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
212static 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
224static 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
238static 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
260error2:
261 unregister_nmi_handler(type: NMI_SERR, name: "hpwdt");
262error1:
263 unregister_nmi_handler(type: NMI_UNKNOWN, name: "hpwdt");
264error:
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
273static void hpwdt_exit_nmi_decoding(void)
274{
275#ifdef CONFIG_HPWDT_NMI_DECODING
276 unregister_nmi_handler(type: NMI_UNKNOWN, name: "hpwdt");
277 unregister_nmi_handler(type: NMI_SERR, name: "hpwdt");
278 unregister_nmi_handler(type: NMI_IO_CHECK, name: "hpwdt");
279#endif
280}
281
282static 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(ids: 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, bar: 1, max: 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, addr: &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(wdd: &hpwdt_dev);
334 watchdog_set_nowayout(wdd: &hpwdt_dev, nowayout);
335 watchdog_init_timeout(wdd: &hpwdt_dev, timeout_parm: 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
364error_wd_register:
365 hpwdt_exit_nmi_decoding();
366error_init_nmi_decoding:
367 pci_iounmap(dev, pci_mem_addr);
368error_pci_iomap:
369 pci_disable_device(dev);
370 return retval;
371}
372
373static 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
381static int hpwdt_suspend(struct device *dev)
382{
383 if (watchdog_active(wdd: &hpwdt_dev))
384 hpwdt_stop();
385
386 return 0;
387}
388
389static int hpwdt_resume(struct device *dev)
390{
391 if (watchdog_active(wdd: &hpwdt_dev))
392 hpwdt_start(wdd: &hpwdt_dev);
393
394 return 0;
395}
396
397static const struct dev_pm_ops hpwdt_pm_ops = {
398 LATE_SYSTEM_SLEEP_PM_OPS(hpwdt_suspend, hpwdt_resume)
399};
400
401static struct pci_driver hpwdt_driver = {
402 .name = "hpwdt",
403 .id_table = hpwdt_devices,
404 .probe = hpwdt_init_one,
405 .remove = hpwdt_exit,
406
407 .driver = {
408 .name = "hpwdt",
409 .pm = &hpwdt_pm_ops,
410 }
411};
412
413MODULE_AUTHOR("Tom Mingarelli");
414MODULE_DESCRIPTION("hpe watchdog driver");
415MODULE_LICENSE("GPL");
416MODULE_VERSION(HPWDT_VERSION);
417
418module_param(soft_margin, int, 0);
419MODULE_PARM_DESC(soft_margin, "Watchdog timeout in seconds");
420
421module_param_named(timeout, soft_margin, int, 0);
422MODULE_PARM_DESC(timeout, "Alias of soft_margin");
423
424module_param(nowayout, bool, 0);
425MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
426 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
427
428module_param(kdumptimeout, int, 0444);
429MODULE_PARM_DESC(kdumptimeout, "Timeout applied for crash kernel transition in seconds");
430
431#ifdef CONFIG_HPWDT_NMI_DECODING
432module_param(pretimeout, bool, 0);
433MODULE_PARM_DESC(pretimeout, "Watchdog pretimeout enabled");
434#endif
435
436module_pci_driver(hpwdt_driver);
437

source code of linux/drivers/watchdog/hpwdt.c