Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * RDC321x watchdog driver
4 *
5 * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
6 *
7 * This driver is highly inspired from the cpu5_wdt driver
8 */
9
10#include <linux/module.h>
11#include <linux/moduleparam.h>
12#include <linux/types.h>
13#include <linux/errno.h>
14#include <linux/miscdevice.h>
15#include <linux/fs.h>
16#include <linux/ioport.h>
17#include <linux/timer.h>
18#include <linux/completion.h>
19#include <linux/jiffies.h>
20#include <linux/platform_device.h>
21#include <linux/watchdog.h>
22#include <linux/io.h>
23#include <linux/uaccess.h>
24#include <linux/mfd/rdc321x.h>
25
26#define RDC_WDT_MASK 0x80000000 /* Mask */
27#define RDC_WDT_EN 0x00800000 /* Enable bit */
28#define RDC_WDT_WTI 0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
29#define RDC_WDT_RST 0x00100000 /* Reset bit */
30#define RDC_WDT_WIF 0x00040000 /* WDT IRQ Flag */
31#define RDC_WDT_IRT 0x00000100 /* IRQ Routing table */
32#define RDC_WDT_CNT 0x00000001 /* WDT count */
33
34#define RDC_CLS_TMR 0x80003844 /* Clear timer */
35
36#define RDC_WDT_INTERVAL (HZ/10+1)
37
38static int ticks = 1000;
39
40/* some device data */
41
42static struct {
43 struct completion stop;
44 int running;
45 struct timer_list timer;
46 int queue;
47 int default_ticks;
48 unsigned long inuse;
49 spinlock_t lock;
50 struct pci_dev *sb_pdev;
51 int base_reg;
52} rdc321x_wdt_device;
53
54/* generic helper functions */
55
56static void rdc321x_wdt_trigger(struct timer_list *unused)
57{
58 unsigned long flags;
59 u32 val;
60
61 if (rdc321x_wdt_device.running)
62 ticks--;
63
64 /* keep watchdog alive */
65 spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
66 pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
67 rdc321x_wdt_device.base_reg, &val);
68 val |= RDC_WDT_EN;
69 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
70 rdc321x_wdt_device.base_reg, val);
71 spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
72
73 /* requeue?? */
74 if (rdc321x_wdt_device.queue && ticks)
75 mod_timer(&rdc321x_wdt_device.timer,
76 jiffies + RDC_WDT_INTERVAL);
77 else {
78 /* ticks doesn't matter anyway */
79 complete(&rdc321x_wdt_device.stop);
80 }
81
82}
83
84static void rdc321x_wdt_reset(void)
85{
86 ticks = rdc321x_wdt_device.default_ticks;
87}
88
89static void rdc321x_wdt_start(void)
90{
91 unsigned long flags;
92
93 if (!rdc321x_wdt_device.queue) {
94 rdc321x_wdt_device.queue = 1;
95
96 /* Clear the timer */
97 spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
98 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
99 rdc321x_wdt_device.base_reg, RDC_CLS_TMR);
100
101 /* Enable watchdog and set the timeout to 81.92 us */
102 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
103 rdc321x_wdt_device.base_reg,
104 RDC_WDT_EN | RDC_WDT_CNT);
105 spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
106
107 mod_timer(&rdc321x_wdt_device.timer,
108 jiffies + RDC_WDT_INTERVAL);
109 }
110
111 /* if process dies, counter is not decremented */
112 rdc321x_wdt_device.running++;
113}
114
115static int rdc321x_wdt_stop(void)
116{
117 if (rdc321x_wdt_device.running)
118 rdc321x_wdt_device.running = 0;
119
120 ticks = rdc321x_wdt_device.default_ticks;
121
122 return -EIO;
123}
124
125/* filesystem operations */
126static int rdc321x_wdt_open(struct inode *inode, struct file *file)
127{
128 if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
129 return -EBUSY;
130
131 return stream_open(inode, file);
132}
133
134static int rdc321x_wdt_release(struct inode *inode, struct file *file)
135{
136 clear_bit(0, &rdc321x_wdt_device.inuse);
137 return 0;
138}
139
140static long rdc321x_wdt_ioctl(struct file *file, unsigned int cmd,
141 unsigned long arg)
142{
143 void __user *argp = (void __user *)arg;
144 u32 value;
145 static const struct watchdog_info ident = {
146 .options = WDIOF_CARDRESET,
147 .identity = "RDC321x WDT",
148 };
149 unsigned long flags;
150
151 switch (cmd) {
152 case WDIOC_KEEPALIVE:
153 rdc321x_wdt_reset();
154 break;
155 case WDIOC_GETSTATUS:
156 /* Read the value from the DATA register */
157 spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
158 pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
159 rdc321x_wdt_device.base_reg, &value);
160 spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
161 if (copy_to_user(argp, &value, sizeof(u32)))
162 return -EFAULT;
163 break;
164 case WDIOC_GETSUPPORT:
165 if (copy_to_user(argp, &ident, sizeof(ident)))
166 return -EFAULT;
167 break;
168 case WDIOC_SETOPTIONS:
169 if (copy_from_user(&value, argp, sizeof(int)))
170 return -EFAULT;
171 switch (value) {
172 case WDIOS_ENABLECARD:
173 rdc321x_wdt_start();
174 break;
175 case WDIOS_DISABLECARD:
176 return rdc321x_wdt_stop();
177 default:
178 return -EINVAL;
179 }
180 break;
181 default:
182 return -ENOTTY;
183 }
184 return 0;
185}
186
187static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf,
188 size_t count, loff_t *ppos)
189{
190 if (!count)
191 return -EIO;
192
193 rdc321x_wdt_reset();
194
195 return count;
196}
197
198static const struct file_operations rdc321x_wdt_fops = {
199 .owner = THIS_MODULE,
200 .llseek = no_llseek,
201 .unlocked_ioctl = rdc321x_wdt_ioctl,
202 .compat_ioctl = compat_ptr_ioctl,
203 .open = rdc321x_wdt_open,
204 .write = rdc321x_wdt_write,
205 .release = rdc321x_wdt_release,
206};
207
208static struct miscdevice rdc321x_wdt_misc = {
209 .minor = WATCHDOG_MINOR,
210 .name = "watchdog",
211 .fops = &rdc321x_wdt_fops,
212};
213
214static int rdc321x_wdt_probe(struct platform_device *pdev)
215{
216 int err;
217 struct resource *r;
218 struct rdc321x_wdt_pdata *pdata;
219
220 pdata = dev_get_platdata(&pdev->dev);
221 if (!pdata) {
222 dev_err(&pdev->dev, "no platform data supplied\n");
223 return -ENODEV;
224 }
225
226 r = platform_get_resource_byname(pdev, IORESOURCE_IO, "wdt-reg");
227 if (!r) {
228 dev_err(&pdev->dev, "failed to get wdt-reg resource\n");
229 return -ENODEV;
230 }
231
232 rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
233 rdc321x_wdt_device.base_reg = r->start;
234 rdc321x_wdt_device.queue = 0;
235 rdc321x_wdt_device.default_ticks = ticks;
236
237 err = misc_register(&rdc321x_wdt_misc);
238 if (err < 0) {
239 dev_err(&pdev->dev, "misc_register failed\n");
240 return err;
241 }
242
243 spin_lock_init(&rdc321x_wdt_device.lock);
244
245 /* Reset the watchdog */
246 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
247 rdc321x_wdt_device.base_reg, RDC_WDT_RST);
248
249 init_completion(&rdc321x_wdt_device.stop);
250
251 clear_bit(0, &rdc321x_wdt_device.inuse);
252
253 timer_setup(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
254
255 dev_info(&pdev->dev, "watchdog init success\n");
256
257 return 0;
258}
259
260static int rdc321x_wdt_remove(struct platform_device *pdev)
261{
262 if (rdc321x_wdt_device.queue) {
263 rdc321x_wdt_device.queue = 0;
264 wait_for_completion(&rdc321x_wdt_device.stop);
265 }
266
267 misc_deregister(&rdc321x_wdt_misc);
268
269 return 0;
270}
271
272static struct platform_driver rdc321x_wdt_driver = {
273 .probe = rdc321x_wdt_probe,
274 .remove = rdc321x_wdt_remove,
275 .driver = {
276 .name = "rdc321x-wdt",
277 },
278};
279
280module_platform_driver(rdc321x_wdt_driver);
281
282MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
283MODULE_DESCRIPTION("RDC321x watchdog driver");
284MODULE_LICENSE("GPL");
1/*
2 * RDC321x watchdog driver
3 *
4 * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
5 *
6 * This driver is highly inspired from the cpu5_wdt driver
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 *
22 */
23
24#include <linux/module.h>
25#include <linux/moduleparam.h>
26#include <linux/types.h>
27#include <linux/errno.h>
28#include <linux/miscdevice.h>
29#include <linux/fs.h>
30#include <linux/ioport.h>
31#include <linux/timer.h>
32#include <linux/completion.h>
33#include <linux/jiffies.h>
34#include <linux/platform_device.h>
35#include <linux/watchdog.h>
36#include <linux/io.h>
37#include <linux/uaccess.h>
38#include <linux/mfd/rdc321x.h>
39
40#define RDC_WDT_MASK 0x80000000 /* Mask */
41#define RDC_WDT_EN 0x00800000 /* Enable bit */
42#define RDC_WDT_WTI 0x00200000 /* Generate CPU reset/NMI/WDT on timeout */
43#define RDC_WDT_RST 0x00100000 /* Reset bit */
44#define RDC_WDT_WIF 0x00040000 /* WDT IRQ Flag */
45#define RDC_WDT_IRT 0x00000100 /* IRQ Routing table */
46#define RDC_WDT_CNT 0x00000001 /* WDT count */
47
48#define RDC_CLS_TMR 0x80003844 /* Clear timer */
49
50#define RDC_WDT_INTERVAL (HZ/10+1)
51
52static int ticks = 1000;
53
54/* some device data */
55
56static struct {
57 struct completion stop;
58 int running;
59 struct timer_list timer;
60 int queue;
61 int default_ticks;
62 unsigned long inuse;
63 spinlock_t lock;
64 struct pci_dev *sb_pdev;
65 int base_reg;
66} rdc321x_wdt_device;
67
68/* generic helper functions */
69
70static void rdc321x_wdt_trigger(unsigned long unused)
71{
72 unsigned long flags;
73 u32 val;
74
75 if (rdc321x_wdt_device.running)
76 ticks--;
77
78 /* keep watchdog alive */
79 spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
80 pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
81 rdc321x_wdt_device.base_reg, &val);
82 val |= RDC_WDT_EN;
83 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
84 rdc321x_wdt_device.base_reg, val);
85 spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
86
87 /* requeue?? */
88 if (rdc321x_wdt_device.queue && ticks)
89 mod_timer(&rdc321x_wdt_device.timer,
90 jiffies + RDC_WDT_INTERVAL);
91 else {
92 /* ticks doesn't matter anyway */
93 complete(&rdc321x_wdt_device.stop);
94 }
95
96}
97
98static void rdc321x_wdt_reset(void)
99{
100 ticks = rdc321x_wdt_device.default_ticks;
101}
102
103static void rdc321x_wdt_start(void)
104{
105 unsigned long flags;
106
107 if (!rdc321x_wdt_device.queue) {
108 rdc321x_wdt_device.queue = 1;
109
110 /* Clear the timer */
111 spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
112 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
113 rdc321x_wdt_device.base_reg, RDC_CLS_TMR);
114
115 /* Enable watchdog and set the timeout to 81.92 us */
116 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
117 rdc321x_wdt_device.base_reg,
118 RDC_WDT_EN | RDC_WDT_CNT);
119 spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
120
121 mod_timer(&rdc321x_wdt_device.timer,
122 jiffies + RDC_WDT_INTERVAL);
123 }
124
125 /* if process dies, counter is not decremented */
126 rdc321x_wdt_device.running++;
127}
128
129static int rdc321x_wdt_stop(void)
130{
131 if (rdc321x_wdt_device.running)
132 rdc321x_wdt_device.running = 0;
133
134 ticks = rdc321x_wdt_device.default_ticks;
135
136 return -EIO;
137}
138
139/* filesystem operations */
140static int rdc321x_wdt_open(struct inode *inode, struct file *file)
141{
142 if (test_and_set_bit(0, &rdc321x_wdt_device.inuse))
143 return -EBUSY;
144
145 return nonseekable_open(inode, file);
146}
147
148static int rdc321x_wdt_release(struct inode *inode, struct file *file)
149{
150 clear_bit(0, &rdc321x_wdt_device.inuse);
151 return 0;
152}
153
154static long rdc321x_wdt_ioctl(struct file *file, unsigned int cmd,
155 unsigned long arg)
156{
157 void __user *argp = (void __user *)arg;
158 u32 value;
159 static const struct watchdog_info ident = {
160 .options = WDIOF_CARDRESET,
161 .identity = "RDC321x WDT",
162 };
163 unsigned long flags;
164
165 switch (cmd) {
166 case WDIOC_KEEPALIVE:
167 rdc321x_wdt_reset();
168 break;
169 case WDIOC_GETSTATUS:
170 /* Read the value from the DATA register */
171 spin_lock_irqsave(&rdc321x_wdt_device.lock, flags);
172 pci_read_config_dword(rdc321x_wdt_device.sb_pdev,
173 rdc321x_wdt_device.base_reg, &value);
174 spin_unlock_irqrestore(&rdc321x_wdt_device.lock, flags);
175 if (copy_to_user(argp, &value, sizeof(u32)))
176 return -EFAULT;
177 break;
178 case WDIOC_GETSUPPORT:
179 if (copy_to_user(argp, &ident, sizeof(ident)))
180 return -EFAULT;
181 break;
182 case WDIOC_SETOPTIONS:
183 if (copy_from_user(&value, argp, sizeof(int)))
184 return -EFAULT;
185 switch (value) {
186 case WDIOS_ENABLECARD:
187 rdc321x_wdt_start();
188 break;
189 case WDIOS_DISABLECARD:
190 return rdc321x_wdt_stop();
191 default:
192 return -EINVAL;
193 }
194 break;
195 default:
196 return -ENOTTY;
197 }
198 return 0;
199}
200
201static ssize_t rdc321x_wdt_write(struct file *file, const char __user *buf,
202 size_t count, loff_t *ppos)
203{
204 if (!count)
205 return -EIO;
206
207 rdc321x_wdt_reset();
208
209 return count;
210}
211
212static const struct file_operations rdc321x_wdt_fops = {
213 .owner = THIS_MODULE,
214 .llseek = no_llseek,
215 .unlocked_ioctl = rdc321x_wdt_ioctl,
216 .open = rdc321x_wdt_open,
217 .write = rdc321x_wdt_write,
218 .release = rdc321x_wdt_release,
219};
220
221static struct miscdevice rdc321x_wdt_misc = {
222 .minor = WATCHDOG_MINOR,
223 .name = "watchdog",
224 .fops = &rdc321x_wdt_fops,
225};
226
227static int rdc321x_wdt_probe(struct platform_device *pdev)
228{
229 int err;
230 struct resource *r;
231 struct rdc321x_wdt_pdata *pdata;
232
233 pdata = dev_get_platdata(&pdev->dev);
234 if (!pdata) {
235 dev_err(&pdev->dev, "no platform data supplied\n");
236 return -ENODEV;
237 }
238
239 r = platform_get_resource_byname(pdev, IORESOURCE_IO, "wdt-reg");
240 if (!r) {
241 dev_err(&pdev->dev, "failed to get wdt-reg resource\n");
242 return -ENODEV;
243 }
244
245 rdc321x_wdt_device.sb_pdev = pdata->sb_pdev;
246 rdc321x_wdt_device.base_reg = r->start;
247
248 err = misc_register(&rdc321x_wdt_misc);
249 if (err < 0) {
250 dev_err(&pdev->dev, "misc_register failed\n");
251 return err;
252 }
253
254 spin_lock_init(&rdc321x_wdt_device.lock);
255
256 /* Reset the watchdog */
257 pci_write_config_dword(rdc321x_wdt_device.sb_pdev,
258 rdc321x_wdt_device.base_reg, RDC_WDT_RST);
259
260 init_completion(&rdc321x_wdt_device.stop);
261 rdc321x_wdt_device.queue = 0;
262
263 clear_bit(0, &rdc321x_wdt_device.inuse);
264
265 setup_timer(&rdc321x_wdt_device.timer, rdc321x_wdt_trigger, 0);
266
267 rdc321x_wdt_device.default_ticks = ticks;
268
269 dev_info(&pdev->dev, "watchdog init success\n");
270
271 return 0;
272}
273
274static int rdc321x_wdt_remove(struct platform_device *pdev)
275{
276 if (rdc321x_wdt_device.queue) {
277 rdc321x_wdt_device.queue = 0;
278 wait_for_completion(&rdc321x_wdt_device.stop);
279 }
280
281 misc_deregister(&rdc321x_wdt_misc);
282
283 return 0;
284}
285
286static struct platform_driver rdc321x_wdt_driver = {
287 .probe = rdc321x_wdt_probe,
288 .remove = rdc321x_wdt_remove,
289 .driver = {
290 .name = "rdc321x-wdt",
291 },
292};
293
294module_platform_driver(rdc321x_wdt_driver);
295
296MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
297MODULE_DESCRIPTION("RDC321x watchdog driver");
298MODULE_LICENSE("GPL");