Merge tag 's390-4.20-2' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
[linux-2.6-block.git] / drivers / watchdog / i6300esb.c
CommitLineData
cc90ef0f 1/*
abda5c8b 2 * i6300esb: Watchdog timer driver for Intel 6300ESB chipset
cc90ef0f
DH
3 *
4 * (c) Copyright 2004 Google Inc.
96de0e25 5 * (c) Copyright 2005 David Härdeman <david@2gen.com>
cc90ef0f
DH
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
7944d3a5 12 * based on i810-tco.c which is in turn based on softdog.c
cc90ef0f 13 *
7944d3a5
WVS
14 * The timer is implemented in the following I/O controller hubs:
15 * (See the intel documentation on http://developer.intel.com.)
0426fd0d 16 * 6300ESB chip : document number 300641-004
cc90ef0f
DH
17 *
18 * 2004YYZZ Ross Biro
19 * Initial version 0.01
20 * 2004YYZZ Ross Biro
7944d3a5 21 * Version 0.02
96de0e25 22 * 20050210 David Härdeman <david@2gen.com>
7944d3a5 23 * Ported driver to kernel 2.6
7af4ac87
RR
24 * 20171016 Radu Rendec <rrendec@arista.com>
25 * Change driver to use the watchdog subsystem
cf73120b 26 * Add support for multiple 6300ESB devices
cc90ef0f
DH
27 */
28
29/*
30 * Includes, defines, variables, module parameters, ...
31 */
32
33#include <linux/module.h>
34#include <linux/types.h>
35#include <linux/kernel.h>
36#include <linux/fs.h>
37#include <linux/mm.h>
38#include <linux/miscdevice.h>
39#include <linux/watchdog.h>
cc90ef0f
DH
40#include <linux/pci.h>
41#include <linux/ioport.h>
0829291e
AC
42#include <linux/uaccess.h>
43#include <linux/io.h>
cc90ef0f 44
cc90ef0f 45/* Module and version information */
cc90ef0f 46#define ESB_MODULE_NAME "i6300ESB timer"
cc90ef0f 47
abda5c8b
DH
48/* PCI configuration registers */
49#define ESB_CONFIG_REG 0x60 /* Config register */
50#define ESB_LOCK_REG 0x68 /* WDT lock register */
51
52/* Memory mapped registers */
cf73120b
RR
53#define ESB_TIMER1_REG(w) ((w)->base + 0x00)/* Timer1 value after each reset */
54#define ESB_TIMER2_REG(w) ((w)->base + 0x04)/* Timer2 value after each reset */
55#define ESB_GINTSR_REG(w) ((w)->base + 0x08)/* General Interrupt Status Reg */
56#define ESB_RELOAD_REG(w) ((w)->base + 0x0c)/* Reload register */
abda5c8b
DH
57
58/* Lock register bits */
0829291e
AC
59#define ESB_WDT_FUNC (0x01 << 2) /* Watchdog functionality */
60#define ESB_WDT_ENABLE (0x01 << 1) /* Enable WDT */
61#define ESB_WDT_LOCK (0x01 << 0) /* Lock (nowayout) */
abda5c8b
DH
62
63/* Config register bits */
0829291e
AC
64#define ESB_WDT_REBOOT (0x01 << 5) /* Enable reboot on timeout */
65#define ESB_WDT_FREQ (0x01 << 2) /* Decrement frequency */
39f3be72 66#define ESB_WDT_INTTYPE (0x03 << 0) /* Interrupt type on timer1 timeout */
abda5c8b
DH
67
68/* Reload register bits */
31838d9d 69#define ESB_WDT_TIMEOUT (0x01 << 9) /* Watchdog timed out */
0829291e 70#define ESB_WDT_RELOAD (0x01 << 8) /* prevent timeout */
abda5c8b
DH
71
72/* Magic constants */
73#define ESB_UNLOCK1 0x80 /* Step 1 to unlock reset registers */
74#define ESB_UNLOCK2 0x86 /* Step 2 to unlock reset registers */
75
cc90ef0f 76/* module parameters */
0829291e 77/* 30 sec default heartbeat (1 < heartbeat < 2*1023) */
568d6015
RR
78#define ESB_HEARTBEAT_MIN 1
79#define ESB_HEARTBEAT_MAX 2046
80#define ESB_HEARTBEAT_DEFAULT 30
81#define ESB_HEARTBEAT_RANGE __MODULE_STRING(ESB_HEARTBEAT_MIN) \
82 "<heartbeat<" __MODULE_STRING(ESB_HEARTBEAT_MAX)
7af4ac87 83static int heartbeat; /* in seconds */
cc90ef0f 84module_param(heartbeat, int, 0);
0829291e 85MODULE_PARM_DESC(heartbeat,
568d6015
RR
86 "Watchdog heartbeat in seconds. (" ESB_HEARTBEAT_RANGE
87 ", default=" __MODULE_STRING(ESB_HEARTBEAT_DEFAULT) ")");
cc90ef0f 88
86a1e189
WVS
89static bool nowayout = WATCHDOG_NOWAYOUT;
90module_param(nowayout, bool, 0);
0829291e
AC
91MODULE_PARM_DESC(nowayout,
92 "Watchdog cannot be stopped once started (default="
93 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
cc90ef0f 94
cf73120b
RR
95/* internal variables */
96struct esb_dev {
97 struct watchdog_device wdd;
98 void __iomem *base;
99 struct pci_dev *pdev;
100};
101
102#define to_esb_dev(wptr) container_of(wptr, struct esb_dev, wdd)
103
cc90ef0f
DH
104/*
105 * Some i6300ESB specific functions
106 */
107
108/*
109 * Prepare for reloading the timer by unlocking the proper registers.
110 * This is performed by first writing 0x80 followed by 0x86 to the
111 * reload register. After this the appropriate registers can be written
112 * to once before they need to be unlocked again.
113 */
cf73120b 114static inline void esb_unlock_registers(struct esb_dev *edev)
7944d3a5 115{
cf73120b
RR
116 writew(ESB_UNLOCK1, ESB_RELOAD_REG(edev));
117 writew(ESB_UNLOCK2, ESB_RELOAD_REG(edev));
cc90ef0f
DH
118}
119
7af4ac87 120static int esb_timer_start(struct watchdog_device *wdd)
cc90ef0f 121{
cf73120b 122 struct esb_dev *edev = to_esb_dev(wdd);
7af4ac87 123 int _wdd_nowayout = test_bit(WDOG_NO_WAY_OUT, &wdd->status);
cc90ef0f
DH
124 u8 val;
125
cf73120b
RR
126 esb_unlock_registers(edev);
127 writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
cc90ef0f 128 /* Enable or Enable + Lock? */
7af4ac87 129 val = ESB_WDT_ENABLE | (_wdd_nowayout ? ESB_WDT_LOCK : 0x00);
cf73120b 130 pci_write_config_byte(edev->pdev, ESB_LOCK_REG, val);
3b9d49ee 131 return 0;
cc90ef0f
DH
132}
133
7af4ac87 134static int esb_timer_stop(struct watchdog_device *wdd)
cc90ef0f 135{
cf73120b 136 struct esb_dev *edev = to_esb_dev(wdd);
cc90ef0f
DH
137 u8 val;
138
cc90ef0f 139 /* First, reset timers as suggested by the docs */
cf73120b
RR
140 esb_unlock_registers(edev);
141 writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
cc90ef0f 142 /* Then disable the WDT */
cf73120b
RR
143 pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x0);
144 pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val);
cc90ef0f
DH
145
146 /* Returns 0 if the timer was disabled, non-zero otherwise */
fc8a9d83 147 return val & ESB_WDT_ENABLE;
cc90ef0f
DH
148}
149
7af4ac87 150static int esb_timer_keepalive(struct watchdog_device *wdd)
cc90ef0f 151{
cf73120b
RR
152 struct esb_dev *edev = to_esb_dev(wdd);
153
154 esb_unlock_registers(edev);
155 writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
0829291e 156 /* FIXME: Do we need to flush anything here? */
7af4ac87 157 return 0;
cc90ef0f
DH
158}
159
7af4ac87
RR
160static int esb_timer_set_heartbeat(struct watchdog_device *wdd,
161 unsigned int time)
cc90ef0f 162{
cf73120b 163 struct esb_dev *edev = to_esb_dev(wdd);
cc90ef0f
DH
164 u32 val;
165
cc90ef0f
DH
166 /* We shift by 9, so if we are passed a value of 1 sec,
167 * val will be 1 << 9 = 512, then write that to two
168 * timers => 2 * 512 = 1024 (which is decremented at 1KHz)
169 */
170 val = time << 9;
171
172 /* Write timer 1 */
cf73120b
RR
173 esb_unlock_registers(edev);
174 writel(val, ESB_TIMER1_REG(edev));
cc90ef0f
DH
175
176 /* Write timer 2 */
cf73120b
RR
177 esb_unlock_registers(edev);
178 writel(val, ESB_TIMER2_REG(edev));
cc90ef0f 179
0829291e 180 /* Reload */
cf73120b
RR
181 esb_unlock_registers(edev);
182 writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
cc90ef0f
DH
183
184 /* FIXME: Do we need to flush everything out? */
185
186 /* Done */
7af4ac87 187 wdd->timeout = time;
cc90ef0f
DH
188 return 0;
189}
190
cc90ef0f 191/*
7af4ac87 192 * Watchdog Subsystem Interfaces
cc90ef0f
DH
193 */
194
7af4ac87
RR
195static struct watchdog_info esb_info = {
196 .identity = ESB_MODULE_NAME,
197 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
198};
cc90ef0f 199
7af4ac87 200static const struct watchdog_ops esb_ops = {
0829291e 201 .owner = THIS_MODULE,
7af4ac87
RR
202 .start = esb_timer_start,
203 .stop = esb_timer_stop,
204 .set_timeout = esb_timer_set_heartbeat,
205 .ping = esb_timer_keepalive,
cc90ef0f
DH
206};
207
cc90ef0f
DH
208/*
209 * Data for PCI driver interface
cc90ef0f 210 */
bc17f9dc 211static const struct pci_device_id esb_pci_tbl[] = {
0829291e
AC
212 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_9), },
213 { 0, }, /* End of list */
cc90ef0f 214};
0829291e 215MODULE_DEVICE_TABLE(pci, esb_pci_tbl);
cc90ef0f
DH
216
217/*
218 * Init & exit routines
219 */
220
cf73120b 221static unsigned char esb_getdevice(struct esb_dev *edev)
cc90ef0f 222{
cf73120b
RR
223 if (pci_enable_device(edev->pdev)) {
224 dev_err(&edev->pdev->dev, "failed to enable device\n");
fc8a9d83
WVS
225 goto err_devput;
226 }
cc90ef0f 227
cf73120b
RR
228 if (pci_request_region(edev->pdev, 0, ESB_MODULE_NAME)) {
229 dev_err(&edev->pdev->dev, "failed to request region\n");
fc8a9d83
WVS
230 goto err_disable;
231 }
cc90ef0f 232
cf73120b
RR
233 edev->base = pci_ioremap_bar(edev->pdev, 0);
234 if (edev->base == NULL) {
fc8a9d83 235 /* Something's wrong here, BASEADDR has to be set */
cf73120b 236 dev_err(&edev->pdev->dev, "failed to get BASEADDR\n");
fc8a9d83
WVS
237 goto err_release;
238 }
239
240 /* Done */
cf73120b 241 dev_set_drvdata(&edev->pdev->dev, edev);
fc8a9d83 242 return 1;
cc90ef0f
DH
243
244err_release:
cf73120b 245 pci_release_region(edev->pdev, 0);
cc90ef0f 246err_disable:
cf73120b 247 pci_disable_device(edev->pdev);
811f9991 248err_devput:
cc90ef0f
DH
249 return 0;
250}
251
cf73120b 252static void esb_initdevice(struct esb_dev *edev)
fc8a9d83
WVS
253{
254 u8 val1;
255 u16 val2;
256
257 /*
258 * Config register:
259 * Bit 5 : 0 = Enable WDT_OUTPUT
260 * Bit 2 : 0 = set the timer frequency to the PCI clock
261 * divided by 2^15 (approx 1KHz).
262 * Bits 1:0 : 11 = WDT_INT_TYPE Disabled.
263 * The watchdog has two timers, it can be setup so that the
264 * expiry of timer1 results in an interrupt and the expiry of
265 * timer2 results in a reboot. We set it to not generate
266 * any interrupts as there is not much we can do with it
267 * right now.
268 */
cf73120b 269 pci_write_config_word(edev->pdev, ESB_CONFIG_REG, 0x0003);
fc8a9d83
WVS
270
271 /* Check that the WDT isn't already locked */
cf73120b 272 pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val1);
fc8a9d83 273 if (val1 & ESB_WDT_LOCK)
cf73120b 274 dev_warn(&edev->pdev->dev, "nowayout already set\n");
fc8a9d83
WVS
275
276 /* Set the timer to watchdog mode and disable it for now */
cf73120b 277 pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x00);
fc8a9d83
WVS
278
279 /* Check if the watchdog was previously triggered */
cf73120b
RR
280 esb_unlock_registers(edev);
281 val2 = readw(ESB_RELOAD_REG(edev));
fc8a9d83 282 if (val2 & ESB_WDT_TIMEOUT)
cf73120b 283 edev->wdd.bootstatus = WDIOF_CARDRESET;
fc8a9d83
WVS
284
285 /* Reset WDT_TIMEOUT flag and timers */
cf73120b
RR
286 esb_unlock_registers(edev);
287 writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG(edev));
fc8a9d83
WVS
288
289 /* And set the correct timeout value */
cf73120b 290 esb_timer_set_heartbeat(&edev->wdd, edev->wdd.timeout);
fc8a9d83
WVS
291}
292
2d991a16 293static int esb_probe(struct pci_dev *pdev,
2786095a 294 const struct pci_device_id *ent)
cc90ef0f 295{
cf73120b 296 struct esb_dev *edev;
0829291e
AC
297 int ret;
298
cf73120b
RR
299 edev = devm_kzalloc(&pdev->dev, sizeof(*edev), GFP_KERNEL);
300 if (!edev)
301 return -ENOMEM;
2786095a 302
0829291e 303 /* Check whether or not the hardware watchdog is there */
cf73120b
RR
304 edev->pdev = pdev;
305 if (!esb_getdevice(edev))
0829291e
AC
306 return -ENODEV;
307
fc8a9d83 308 /* Initialize the watchdog and make sure it does not run */
cf73120b
RR
309 edev->wdd.info = &esb_info;
310 edev->wdd.ops = &esb_ops;
568d6015
RR
311 edev->wdd.min_timeout = ESB_HEARTBEAT_MIN;
312 edev->wdd.max_timeout = ESB_HEARTBEAT_MAX;
313 edev->wdd.timeout = ESB_HEARTBEAT_DEFAULT;
cf73120b
RR
314 if (watchdog_init_timeout(&edev->wdd, heartbeat, NULL))
315 dev_info(&pdev->dev,
568d6015
RR
316 "heartbeat value must be " ESB_HEARTBEAT_RANGE
317 ", using %u\n", edev->wdd.timeout);
cf73120b
RR
318 watchdog_set_nowayout(&edev->wdd, nowayout);
319 watchdog_stop_on_reboot(&edev->wdd);
320 watchdog_stop_on_unregister(&edev->wdd);
321 esb_initdevice(edev);
fc8a9d83
WVS
322
323 /* Register the watchdog so that userspace has access to it */
cf73120b 324 ret = watchdog_register_device(&edev->wdd);
0829291e 325 if (ret != 0) {
7af4ac87
RR
326 dev_err(&pdev->dev,
327 "cannot register watchdog device (err=%d)\n", ret);
0426fd0d 328 goto err_unmap;
0829291e 329 }
7af4ac87
RR
330 dev_info(&pdev->dev,
331 "initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
cf73120b 332 edev->base, edev->wdd.timeout, nowayout);
0829291e 333 return 0;
cc90ef0f 334
cc90ef0f 335err_unmap:
cf73120b
RR
336 iounmap(edev->base);
337 pci_release_region(edev->pdev, 0);
338 pci_disable_device(edev->pdev);
0829291e 339 return ret;
cc90ef0f
DH
340}
341
4b12b896 342static void esb_remove(struct pci_dev *pdev)
cc90ef0f 343{
cf73120b
RR
344 struct esb_dev *edev = dev_get_drvdata(&pdev->dev);
345
346 watchdog_unregister_device(&edev->wdd);
347 iounmap(edev->base);
348 pci_release_region(edev->pdev, 0);
349 pci_disable_device(edev->pdev);
0426fd0d
WVS
350}
351
2786095a
WVS
352static struct pci_driver esb_driver = {
353 .name = ESB_MODULE_NAME,
354 .id_table = esb_pci_tbl,
0426fd0d 355 .probe = esb_probe,
82268714 356 .remove = esb_remove,
0426fd0d
WVS
357};
358
5ce9c371 359module_pci_driver(esb_driver);
cc90ef0f 360
96de0e25 361MODULE_AUTHOR("Ross Biro and David Härdeman");
cc90ef0f
DH
362MODULE_DESCRIPTION("Watchdog driver for Intel 6300ESB chipsets");
363MODULE_LICENSE("GPL");