1 /* linux/drivers/watchdog/rk29_wdt.c
\r
3 * Copyright (C) 2011 ROCKCHIP, Inc.
\r
6 * This program is free software; you can redistribute it and/or modify
\r
7 * it under the terms of the GNU General Public License as published by
\r
8 * the Free Software Foundation; either version 2 of the License, or
\r
9 * (at your option) any later version.
\r
11 * This program is distributed in the hope that it will be useful,
\r
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
\r
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
\r
14 * GNU General Public License for more details.
\r
16 * You should have received a copy of the GNU General Public License
\r
17 * along with this program; if not, write to the Free Software
\r
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
\r
22 #include <linux/module.h>
\r
23 #include <linux/moduleparam.h>
\r
24 #include <linux/types.h>
\r
25 #include <linux/timer.h>
\r
26 #include <linux/miscdevice.h>
\r
27 #include <linux/watchdog.h>
\r
28 #include <linux/fs.h>
\r
29 #include <linux/init.h>
\r
30 #include <linux/platform_device.h>
\r
31 #include <linux/interrupt.h>
\r
32 #include <linux/clk.h>
\r
33 #include <linux/uaccess.h>
\r
34 #include <linux/io.h>
\r
35 #include <asm/mach/map.h>
\r
38 /* RK29 registers define */
\r
39 #define RK29_WDT_CR 0X00
\r
40 #define RK29_WDT_TORR 0X04
\r
41 #define RK29_WDT_CCVR 0X08
\r
42 #define RK29_WDT_CRR 0X0C
\r
43 #define RK29_WDT_STAT 0X10
\r
44 #define RK29_WDT_EOI 0X14
\r
46 #define RK29_WDT_EN 1
\r
47 #define RK29_RESPONSE_MODE 1
\r
48 #define RK29_RESET_PULSE 4
\r
50 //THAT wdt's clock is 24MHZ
\r
51 #define RK29_WDT_2730US 0
\r
52 #define RK29_WDT_5460US 1
\r
53 #define RK29_WDT_10920US 2
\r
54 #define RK29_WDT_21840US 3
\r
55 #define RK29_WDT_43680US 4
\r
56 #define RK29_WDT_87360US 5
\r
57 #define RK29_WDT_174720US 6
\r
58 #define RK29_WDT_349440US 7
\r
59 #define RK29_WDT_698880US 8
\r
60 #define RK29_WDT_1397760US 9
\r
61 #define RK29_WDT_2795520US 10
\r
62 #define RK29_WDT_5591040US 11
\r
63 #define RK29_WDT_11182080US 12
\r
64 #define RK29_WDT_22364160US 13
\r
65 #define RK29_WDT_44728320US 14
\r
66 #define RK29_WDT_89456640US 15
\r
69 #define CONFIG_RK29_WATCHDOG_ATBOOT (1)
\r
70 #define CONFIG_RK29_WATCHDOG_DEFAULT_TIME 10 //unit second
\r
71 #define CONFIG_RK29_WATCHDOG_DEBUG 1
\r
74 static int nowayout = WATCHDOG_NOWAYOUT;
\r
75 static int tmr_margin = CONFIG_RK29_WATCHDOG_DEFAULT_TIME;
\r
76 #ifdef CONFIG_RK29_WATCHDOG_ATBOOT
\r
77 static int tmr_atboot = 1;
\r
79 static int tmr_atboot = 0;
\r
82 static int soft_noboot;
\r
84 #ifdef CONFIG_RK29_WATCHDOG_DEBUG
\r
85 static int debug = 1;
\r
87 static int debug = 0;
\r
90 module_param(tmr_margin, int, 0);
\r
91 module_param(tmr_atboot, int, 0);
\r
92 module_param(nowayout, int, 0);
\r
93 module_param(soft_noboot, int, 0);
\r
94 module_param(debug, int, 0);
\r
96 MODULE_PARM_DESC(tmr_margin, "Watchdog tmr_margin in seconds. default="
\r
97 __MODULE_STRING(CONFIG_RK29_WATCHDOG_DEFAULT_TIME) ")");
\r
98 MODULE_PARM_DESC(tmr_atboot,
\r
99 "Watchdog is started at boot time if set to 1, default="
\r
100 __MODULE_STRING(CONFIG_RK29_WATCHDOG_ATBOOT));
\r
101 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
\r
102 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
\r
103 MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
\r
104 "0 to reboot (default depends on ONLY_TESTING)");
\r
105 MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug, (default 0)");
\r
108 static unsigned long open_lock;
\r
109 static struct device *wdt_dev; /* platform device attached to */
\r
110 static struct resource *wdt_mem;
\r
111 static struct resource *wdt_irq;
\r
112 static struct clk *wdt_clock;
\r
113 static void __iomem *wdt_base;
\r
114 static char expect_close;
\r
117 /* watchdog control routines */
\r
119 #define DBG(msg...) do { \
\r
121 printk(KERN_INFO msg); \
\r
124 #define wdt_writel(v, offset) do { writel_relaxed(v, wdt_base + offset); dsb(); } while (0)
\r
127 void rk29_wdt_keepalive(void)
\r
130 wdt_writel(0x76, RK29_WDT_CRR);
\r
133 static void __rk29_wdt_stop(void)
\r
135 rk29_wdt_keepalive(); //feed dog
\r
136 wdt_writel(0x0a, RK29_WDT_CR);
\r
139 void rk29_wdt_stop(void)
\r
142 clk_disable(wdt_clock);
\r
145 /* timeout unit second */
\r
146 int rk29_wdt_set_heartbeat(int timeout)
\r
148 unsigned int count = 0;
\r
149 unsigned int torr = 0, acc = 1, maxtime = 0;
\r
150 unsigned int freq = clk_get_rate(wdt_clock);
\r
154 //0x80000000 is the max count of watch dog
\r
155 maxtime = 0x80000000 / freq + 1;
\r
156 if(timeout > maxtime)
\r
159 count = timeout * freq;
\r
162 while(acc < count){
\r
169 DBG("%s:torr:%d, count:%d, maxtime:%d s\n", __func__, torr, count, maxtime);
\r
170 wdt_writel(torr, RK29_WDT_TORR);
\r
174 void rk29_wdt_start(void)
\r
176 unsigned long wtcon;
\r
177 clk_enable(wdt_clock);
\r
178 rk29_wdt_set_heartbeat(tmr_margin);
\r
179 wtcon = (RK29_WDT_EN << 0) | (RK29_RESPONSE_MODE << 1) | (RK29_RESET_PULSE << 2);
\r
180 wdt_writel(wtcon, RK29_WDT_CR);
\r
184 * /dev/watchdog handling
\r
187 static int rk29_wdt_open(struct inode *inode, struct file *file)
\r
189 DBG("%s\n", __func__);
\r
190 if (test_and_set_bit(0, &open_lock))
\r
194 __module_get(THIS_MODULE);
\r
198 /* start the timer */
\r
200 return nonseekable_open(inode, file);
\r
203 static int rk29_wdt_release(struct inode *inode, struct file *file)
\r
206 * Shut off the timer.
\r
207 * Lock it in if it's a module and we set nowayout
\r
209 DBG("%s\n", __func__);
\r
210 if (expect_close == 42)
\r
213 dev_err(wdt_dev, "Unexpected close, not stopping watchdog\n");
\r
214 rk29_wdt_keepalive();
\r
217 clear_bit(0, &open_lock);
\r
221 static ssize_t rk29_wdt_write(struct file *file, const char __user *data,
\r
222 size_t len, loff_t *ppos)
\r
225 * Refresh the timer.
\r
227 DBG("%s\n", __func__);
\r
232 /* In case it was set long ago */
\r
235 for (i = 0; i != len; i++) {
\r
238 if (get_user(c, data + i))
\r
244 rk29_wdt_keepalive();
\r
249 #define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
\r
251 static const struct watchdog_info rk29_wdt_ident = {
\r
252 .options = OPTIONS,
\r
253 .firmware_version = 0,
\r
254 .identity = "rk29 Watchdog",
\r
258 static long rk29_wdt_ioctl(struct file *file, unsigned int cmd,
\r
261 void __user *argp = (void __user *)arg;
\r
262 int __user *p = argp;
\r
264 DBG("%s\n", __func__);
\r
266 case WDIOC_GETSUPPORT:
\r
267 return copy_to_user(argp, &rk29_wdt_ident,
\r
268 sizeof(rk29_wdt_ident)) ? -EFAULT : 0;
\r
269 case WDIOC_GETSTATUS:
\r
270 case WDIOC_GETBOOTSTATUS:
\r
271 return put_user(0, p);
\r
272 case WDIOC_KEEPALIVE:
\r
273 DBG("%s:rk29_wdt_keepalive\n", __func__);
\r
274 rk29_wdt_keepalive();
\r
276 case WDIOC_SETTIMEOUT:
\r
277 if (get_user(new_margin, p))
\r
279 if (rk29_wdt_set_heartbeat(new_margin))
\r
281 rk29_wdt_keepalive();
\r
282 return put_user(tmr_margin, p);
\r
283 case WDIOC_GETTIMEOUT:
\r
284 return put_user(tmr_margin, p);
\r
292 /* kernel interface */
\r
294 static const struct file_operations rk29_wdt_fops = {
\r
295 .owner = THIS_MODULE,
\r
296 .llseek = no_llseek,
\r
297 .write = rk29_wdt_write,
\r
298 .unlocked_ioctl = rk29_wdt_ioctl,
\r
299 .open = rk29_wdt_open,
\r
300 .release = rk29_wdt_release,
\r
303 static struct miscdevice rk29_wdt_miscdev = {
\r
304 .minor = WATCHDOG_MINOR,
\r
305 .name = "watchdog",
\r
306 .fops = &rk29_wdt_fops,
\r
310 /* interrupt handler code */
\r
312 static irqreturn_t rk29_wdt_irq_handler(int irqno, void *param)
\r
314 DBG("RK29_wdt:watchdog timer expired (irq)\n");
\r
315 rk29_wdt_keepalive();
\r
316 return IRQ_HANDLED;
\r
320 /* device interface */
\r
322 static int __devinit rk29_wdt_probe(struct platform_device *pdev)
\r
324 struct resource *res;
\r
325 struct device *dev;
\r
331 wdt_dev = &pdev->dev;
\r
333 /* get the memory region for the watchdog timer */
\r
335 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
\r
337 dev_err(dev, "no memory resource specified\n");
\r
341 size = (res->end - res->start) + 1;
\r
342 wdt_mem = request_mem_region(res->start, size, pdev->name);
\r
343 if (wdt_mem == NULL) {
\r
344 dev_err(dev, "failed to get memory region\n");
\r
349 wdt_base = ioremap(res->start, size);
\r
350 if (wdt_base == NULL) {
\r
351 dev_err(dev, "failed to ioremap() region\n");
\r
356 DBG("probe: mapped wdt_base=%p\n", wdt_base);
\r
359 #ifdef CONFIG_RK29_FEED_DOG_BY_INTE
\r
361 wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
\r
362 if (wdt_irq == NULL) {
\r
363 dev_err(dev, "no irq resource specified\n");
\r
368 ret = request_irq(wdt_irq->start, rk29_wdt_irq_handler, 0, pdev->name, pdev);
\r
371 dev_err(dev, "failed to install irq (%d)\n", ret);
\r
377 wdt_clock = clk_get(&pdev->dev, "wdt");
\r
378 if (IS_ERR(wdt_clock)) {
\r
379 wdt_clock = clk_get(&pdev->dev, "pclk_wdt");
\r
381 if (IS_ERR(wdt_clock)) {
\r
382 dev_err(dev, "failed to find watchdog clock source\n");
\r
383 ret = PTR_ERR(wdt_clock);
\r
387 ret = misc_register(&rk29_wdt_miscdev);
\r
389 dev_err(dev, "cannot register miscdev on minor=%d (%d)\n",
\r
390 WATCHDOG_MINOR, ret);
\r
393 if (tmr_atboot && started == 0) {
\r
394 dev_info(dev, "starting watchdog timer\n");
\r
396 } else if (!tmr_atboot) {
\r
397 /* if we're not enabling the watchdog, then ensure it is
\r
398 * disabled if it has been left running from the bootloader
\r
399 * or other source */
\r
407 clk_disable(wdt_clock);
\r
408 clk_put(wdt_clock);
\r
411 free_irq(wdt_irq->start, pdev);
\r
417 release_resource(wdt_mem);
\r
423 static int __devexit rk29_wdt_remove(struct platform_device *dev)
\r
425 release_resource(wdt_mem);
\r
429 free_irq(wdt_irq->start, dev);
\r
432 clk_disable(wdt_clock);
\r
433 clk_put(wdt_clock);
\r
437 misc_deregister(&rk29_wdt_miscdev);
\r
442 static void rk29_wdt_shutdown(struct platform_device *dev)
\r
449 static int rk29_wdt_suspend(struct platform_device *dev, pm_message_t state)
\r
455 static int rk29_wdt_resume(struct platform_device *dev)
\r
462 #define rk29_wdt_suspend NULL
\r
463 #define rk29_wdt_resume NULL
\r
464 #endif /* CONFIG_PM */
\r
467 static struct platform_driver rk29_wdt_driver = {
\r
468 .probe = rk29_wdt_probe,
\r
469 .remove = __devexit_p(rk29_wdt_remove),
\r
470 .shutdown = rk29_wdt_shutdown,
\r
471 .suspend = rk29_wdt_suspend,
\r
472 .resume = rk29_wdt_resume,
\r
474 .owner = THIS_MODULE,
\r
475 .name = "rk29-wdt",
\r
480 static char banner[] __initdata =
\r
481 KERN_INFO "RK29 Watchdog Timer, (c) 2011 Rockchip Electronics\n";
\r
483 static int __init watchdog_init(void)
\r
486 return platform_driver_register(&rk29_wdt_driver);
\r
489 static void __exit watchdog_exit(void)
\r
491 platform_driver_unregister(&rk29_wdt_driver);
\r
494 subsys_initcall(watchdog_init);
\r
495 module_exit(watchdog_exit);
\r
497 MODULE_AUTHOR("hhb@rock-chips.com");
\r
498 MODULE_DESCRIPTION("RK29 Watchdog Device Driver");
\r
499 MODULE_LICENSE("GPL");
\r
500 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
\r
501 MODULE_ALIAS("platform:rk29-wdt");
\r