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Commit | Line | Data |
---|---|---|
7768a13c | 1 | /* |
2817142f | 2 | * omap_wdt.c |
7768a13c | 3 | * |
2817142f | 4 | * Watchdog driver for the TI OMAP 16xx & 24xx/34xx 32KHz (non-secure) watchdog |
7768a13c KS |
5 | * |
6 | * Author: MontaVista Software, Inc. | |
7 | * <gdavis@mvista.com> or <source@mvista.com> | |
8 | * | |
9 | * 2003 (c) MontaVista Software, Inc. This file is licensed under the | |
10 | * terms of the GNU General Public License version 2. This program is | |
11 | * licensed "as is" without any warranty of any kind, whether express | |
12 | * or implied. | |
13 | * | |
14 | * History: | |
15 | * | |
16 | * 20030527: George G. Davis <gdavis@mvista.com> | |
17 | * Initially based on linux-2.4.19-rmk7-pxa1/drivers/char/sa1100_wdt.c | |
18 | * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> | |
19 | * Based on SoftDog driver by Alan Cox <alan@redhat.com> | |
20 | * | |
21 | * Copyright (c) 2004 Texas Instruments. | |
22 | * 1. Modified to support OMAP1610 32-KHz watchdog timer | |
23 | * 2. Ported to 2.6 kernel | |
24 | * | |
25 | * Copyright (c) 2005 David Brownell | |
26 | * Use the driver model and standard identifiers; handle bigger timeouts. | |
27 | */ | |
28 | ||
29 | #include <linux/module.h> | |
7768a13c KS |
30 | #include <linux/types.h> |
31 | #include <linux/kernel.h> | |
32 | #include <linux/fs.h> | |
33 | #include <linux/mm.h> | |
34 | #include <linux/miscdevice.h> | |
35 | #include <linux/watchdog.h> | |
36 | #include <linux/reboot.h> | |
7768a13c KS |
37 | #include <linux/init.h> |
38 | #include <linux/err.h> | |
39 | #include <linux/platform_device.h> | |
40 | #include <linux/moduleparam.h> | |
41 | #include <linux/clk.h> | |
1977f032 | 42 | #include <linux/bitops.h> |
089ab079 | 43 | #include <linux/io.h> |
12b9df7d | 44 | #include <linux/uaccess.h> |
a09e64fb | 45 | #include <mach/hardware.h> |
a09e64fb | 46 | #include <mach/prcm.h> |
7768a13c KS |
47 | |
48 | #include "omap_wdt.h" | |
49 | ||
2817142f FB |
50 | static struct platform_device *omap_wdt_dev; |
51 | ||
7768a13c KS |
52 | static unsigned timer_margin; |
53 | module_param(timer_margin, uint, 0); | |
54 | MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)"); | |
55 | ||
7768a13c | 56 | static unsigned int wdt_trgr_pattern = 0x1234; |
12b9df7d | 57 | static spinlock_t wdt_lock; |
7768a13c | 58 | |
2817142f FB |
59 | struct omap_wdt_dev { |
60 | void __iomem *base; /* physical */ | |
61 | struct device *dev; | |
62 | int omap_wdt_users; | |
63 | struct clk *armwdt_ck; | |
64 | struct clk *mpu_wdt_ick; | |
65 | struct clk *mpu_wdt_fck; | |
66 | struct resource *mem; | |
67 | struct miscdevice omap_wdt_miscdev; | |
68 | }; | |
69 | ||
70 | static void omap_wdt_ping(struct omap_wdt_dev *wdev) | |
7768a13c | 71 | { |
2817142f | 72 | void __iomem *base = wdev->base; |
7768a13c | 73 | /* wait for posted write to complete */ |
9f69e3b0 | 74 | while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08) |
7768a13c KS |
75 | cpu_relax(); |
76 | wdt_trgr_pattern = ~wdt_trgr_pattern; | |
9f69e3b0 | 77 | __raw_writel(wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR)); |
7768a13c | 78 | /* wait for posted write to complete */ |
9f69e3b0 | 79 | while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08) |
7768a13c KS |
80 | cpu_relax(); |
81 | /* reloaded WCRR from WLDR */ | |
82 | } | |
83 | ||
2817142f | 84 | static void omap_wdt_enable(struct omap_wdt_dev *wdev) |
7768a13c | 85 | { |
2817142f FB |
86 | void __iomem *base; |
87 | base = wdev->base; | |
7768a13c | 88 | /* Sequence to enable the watchdog */ |
9f69e3b0 FB |
89 | __raw_writel(0xBBBB, base + OMAP_WATCHDOG_SPR); |
90 | while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x10) | |
7768a13c | 91 | cpu_relax(); |
9f69e3b0 FB |
92 | __raw_writel(0x4444, base + OMAP_WATCHDOG_SPR); |
93 | while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x10) | |
7768a13c KS |
94 | cpu_relax(); |
95 | } | |
96 | ||
2817142f | 97 | static void omap_wdt_disable(struct omap_wdt_dev *wdev) |
7768a13c | 98 | { |
2817142f FB |
99 | void __iomem *base; |
100 | base = wdev->base; | |
7768a13c | 101 | /* sequence required to disable watchdog */ |
9f69e3b0 FB |
102 | __raw_writel(0xAAAA, base + OMAP_WATCHDOG_SPR); /* TIMER_MODE */ |
103 | while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x10) | |
7768a13c | 104 | cpu_relax(); |
9f69e3b0 FB |
105 | __raw_writel(0x5555, base + OMAP_WATCHDOG_SPR); /* TIMER_MODE */ |
106 | while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x10) | |
7768a13c KS |
107 | cpu_relax(); |
108 | } | |
109 | ||
110 | static void omap_wdt_adjust_timeout(unsigned new_timeout) | |
111 | { | |
112 | if (new_timeout < TIMER_MARGIN_MIN) | |
113 | new_timeout = TIMER_MARGIN_DEFAULT; | |
114 | if (new_timeout > TIMER_MARGIN_MAX) | |
115 | new_timeout = TIMER_MARGIN_MAX; | |
116 | timer_margin = new_timeout; | |
117 | } | |
118 | ||
2817142f | 119 | static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev) |
7768a13c KS |
120 | { |
121 | u32 pre_margin = GET_WLDR_VAL(timer_margin); | |
2817142f FB |
122 | void __iomem *base; |
123 | base = wdev->base; | |
7768a13c KS |
124 | |
125 | /* just count up at 32 KHz */ | |
9f69e3b0 | 126 | while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04) |
7768a13c | 127 | cpu_relax(); |
9f69e3b0 FB |
128 | __raw_writel(pre_margin, base + OMAP_WATCHDOG_LDR); |
129 | while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04) | |
7768a13c KS |
130 | cpu_relax(); |
131 | } | |
132 | ||
133 | /* | |
134 | * Allow only one task to hold it open | |
135 | */ | |
136 | ||
137 | static int omap_wdt_open(struct inode *inode, struct file *file) | |
138 | { | |
2817142f FB |
139 | struct omap_wdt_dev *wdev; |
140 | void __iomem *base; | |
141 | wdev = platform_get_drvdata(omap_wdt_dev); | |
142 | base = wdev->base; | |
143 | if (test_and_set_bit(1, (unsigned long *)&(wdev->omap_wdt_users))) | |
7768a13c KS |
144 | return -EBUSY; |
145 | ||
146 | if (cpu_is_omap16xx()) | |
2817142f | 147 | clk_enable(wdev->armwdt_ck); /* Enable the clock */ |
7768a13c | 148 | |
2817142f FB |
149 | if (cpu_is_omap24xx() || cpu_is_omap34xx()) { |
150 | clk_enable(wdev->mpu_wdt_ick); /* Enable the interface clock */ | |
151 | clk_enable(wdev->mpu_wdt_fck); /* Enable the functional clock */ | |
7768a13c KS |
152 | } |
153 | ||
154 | /* initialize prescaler */ | |
9f69e3b0 | 155 | while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01) |
7768a13c | 156 | cpu_relax(); |
9f69e3b0 FB |
157 | __raw_writel((1 << 5) | (PTV << 2), base + OMAP_WATCHDOG_CNTRL); |
158 | while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01) | |
7768a13c KS |
159 | cpu_relax(); |
160 | ||
2817142f FB |
161 | file->private_data = (void *) wdev; |
162 | ||
163 | omap_wdt_set_timeout(wdev); | |
164 | omap_wdt_enable(wdev); | |
ec9505a7 | 165 | return nonseekable_open(inode, file); |
7768a13c KS |
166 | } |
167 | ||
168 | static int omap_wdt_release(struct inode *inode, struct file *file) | |
169 | { | |
2817142f FB |
170 | struct omap_wdt_dev *wdev; |
171 | wdev = file->private_data; | |
7768a13c KS |
172 | /* |
173 | * Shut off the timer unless NOWAYOUT is defined. | |
174 | */ | |
175 | #ifndef CONFIG_WATCHDOG_NOWAYOUT | |
7768a13c | 176 | |
2817142f | 177 | omap_wdt_disable(wdev); |
7768a13c | 178 | |
2817142f FB |
179 | if (cpu_is_omap16xx()) |
180 | clk_disable(wdev->armwdt_ck); /* Disable the clock */ | |
181 | ||
182 | if (cpu_is_omap24xx() || cpu_is_omap34xx()) { | |
183 | clk_disable(wdev->mpu_wdt_ick); /* Disable the clock */ | |
184 | clk_disable(wdev->mpu_wdt_fck); /* Disable the clock */ | |
7768a13c KS |
185 | } |
186 | #else | |
187 | printk(KERN_CRIT "omap_wdt: Unexpected close, not stopping!\n"); | |
188 | #endif | |
2817142f | 189 | wdev->omap_wdt_users = 0; |
7768a13c KS |
190 | return 0; |
191 | } | |
192 | ||
12b9df7d | 193 | static ssize_t omap_wdt_write(struct file *file, const char __user *data, |
7768a13c KS |
194 | size_t len, loff_t *ppos) |
195 | { | |
2817142f FB |
196 | struct omap_wdt_dev *wdev; |
197 | wdev = file->private_data; | |
7768a13c | 198 | /* Refresh LOAD_TIME. */ |
12b9df7d AC |
199 | if (len) { |
200 | spin_lock(&wdt_lock); | |
2817142f | 201 | omap_wdt_ping(wdev); |
12b9df7d AC |
202 | spin_unlock(&wdt_lock); |
203 | } | |
7768a13c KS |
204 | return len; |
205 | } | |
206 | ||
12b9df7d AC |
207 | static long omap_wdt_ioctl(struct file *file, unsigned int cmd, |
208 | unsigned long arg) | |
7768a13c | 209 | { |
2817142f | 210 | struct omap_wdt_dev *wdev; |
7768a13c | 211 | int new_margin; |
12b9df7d | 212 | static const struct watchdog_info ident = { |
7768a13c KS |
213 | .identity = "OMAP Watchdog", |
214 | .options = WDIOF_SETTIMEOUT, | |
215 | .firmware_version = 0, | |
216 | }; | |
2817142f | 217 | wdev = file->private_data; |
7768a13c KS |
218 | |
219 | switch (cmd) { | |
7768a13c KS |
220 | case WDIOC_GETSUPPORT: |
221 | return copy_to_user((struct watchdog_info __user *)arg, &ident, | |
222 | sizeof(ident)); | |
223 | case WDIOC_GETSTATUS: | |
224 | return put_user(0, (int __user *)arg); | |
225 | case WDIOC_GETBOOTSTATUS: | |
226 | if (cpu_is_omap16xx()) | |
9f69e3b0 | 227 | return put_user(__raw_readw(ARM_SYSST), |
7768a13c KS |
228 | (int __user *)arg); |
229 | if (cpu_is_omap24xx()) | |
230 | return put_user(omap_prcm_get_reset_sources(), | |
231 | (int __user *)arg); | |
232 | case WDIOC_KEEPALIVE: | |
12b9df7d | 233 | spin_lock(&wdt_lock); |
2817142f | 234 | omap_wdt_ping(wdev); |
12b9df7d | 235 | spin_unlock(&wdt_lock); |
7768a13c KS |
236 | return 0; |
237 | case WDIOC_SETTIMEOUT: | |
238 | if (get_user(new_margin, (int __user *)arg)) | |
239 | return -EFAULT; | |
240 | omap_wdt_adjust_timeout(new_margin); | |
241 | ||
12b9df7d | 242 | spin_lock(&wdt_lock); |
2817142f FB |
243 | omap_wdt_disable(wdev); |
244 | omap_wdt_set_timeout(wdev); | |
245 | omap_wdt_enable(wdev); | |
7768a13c | 246 | |
2817142f | 247 | omap_wdt_ping(wdev); |
12b9df7d | 248 | spin_unlock(&wdt_lock); |
7768a13c KS |
249 | /* Fall */ |
250 | case WDIOC_GETTIMEOUT: | |
251 | return put_user(timer_margin, (int __user *)arg); | |
0c06090c WVS |
252 | default: |
253 | return -ENOTTY; | |
7768a13c KS |
254 | } |
255 | } | |
256 | ||
2b8693c0 | 257 | static const struct file_operations omap_wdt_fops = { |
7768a13c KS |
258 | .owner = THIS_MODULE, |
259 | .write = omap_wdt_write, | |
12b9df7d | 260 | .unlocked_ioctl = omap_wdt_ioctl, |
7768a13c KS |
261 | .open = omap_wdt_open, |
262 | .release = omap_wdt_release, | |
263 | }; | |
264 | ||
7768a13c KS |
265 | |
266 | static int __init omap_wdt_probe(struct platform_device *pdev) | |
267 | { | |
268 | struct resource *res, *mem; | |
269 | int ret; | |
2817142f | 270 | struct omap_wdt_dev *wdev; |
7768a13c KS |
271 | |
272 | /* reserve static register mappings */ | |
273 | res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
274 | if (!res) | |
275 | return -ENOENT; | |
276 | ||
2817142f FB |
277 | if (omap_wdt_dev) |
278 | return -EBUSY; | |
279 | ||
7768a13c KS |
280 | mem = request_mem_region(res->start, res->end - res->start + 1, |
281 | pdev->name); | |
282 | if (mem == NULL) | |
283 | return -EBUSY; | |
284 | ||
2817142f FB |
285 | wdev = kzalloc(sizeof(struct omap_wdt_dev), GFP_KERNEL); |
286 | if (!wdev) { | |
287 | ret = -ENOMEM; | |
288 | goto fail; | |
289 | } | |
290 | wdev->omap_wdt_users = 0; | |
291 | wdev->mem = mem; | |
7768a13c KS |
292 | |
293 | if (cpu_is_omap16xx()) { | |
2817142f FB |
294 | wdev->armwdt_ck = clk_get(&pdev->dev, "armwdt_ck"); |
295 | if (IS_ERR(wdev->armwdt_ck)) { | |
296 | ret = PTR_ERR(wdev->armwdt_ck); | |
297 | wdev->armwdt_ck = NULL; | |
7768a13c KS |
298 | goto fail; |
299 | } | |
300 | } | |
301 | ||
302 | if (cpu_is_omap24xx()) { | |
2817142f FB |
303 | wdev->mpu_wdt_ick = clk_get(&pdev->dev, "mpu_wdt_ick"); |
304 | if (IS_ERR(wdev->mpu_wdt_ick)) { | |
305 | ret = PTR_ERR(wdev->mpu_wdt_ick); | |
306 | wdev->mpu_wdt_ick = NULL; | |
307 | goto fail; | |
308 | } | |
309 | wdev->mpu_wdt_fck = clk_get(&pdev->dev, "mpu_wdt_fck"); | |
310 | if (IS_ERR(wdev->mpu_wdt_fck)) { | |
311 | ret = PTR_ERR(wdev->mpu_wdt_fck); | |
312 | wdev->mpu_wdt_fck = NULL; | |
313 | goto fail; | |
314 | } | |
315 | } | |
316 | ||
317 | if (cpu_is_omap34xx()) { | |
318 | wdev->mpu_wdt_ick = clk_get(&pdev->dev, "wdt2_ick"); | |
319 | if (IS_ERR(wdev->mpu_wdt_ick)) { | |
320 | ret = PTR_ERR(wdev->mpu_wdt_ick); | |
321 | wdev->mpu_wdt_ick = NULL; | |
7768a13c KS |
322 | goto fail; |
323 | } | |
2817142f FB |
324 | wdev->mpu_wdt_fck = clk_get(&pdev->dev, "wdt2_fck"); |
325 | if (IS_ERR(wdev->mpu_wdt_fck)) { | |
326 | ret = PTR_ERR(wdev->mpu_wdt_fck); | |
327 | wdev->mpu_wdt_fck = NULL; | |
7768a13c KS |
328 | goto fail; |
329 | } | |
330 | } | |
9f69e3b0 FB |
331 | wdev->base = ioremap(res->start, res->end - res->start + 1); |
332 | if (!wdev->base) { | |
333 | ret = -ENOMEM; | |
334 | goto fail; | |
335 | } | |
336 | ||
2817142f | 337 | platform_set_drvdata(pdev, wdev); |
7768a13c | 338 | |
2817142f | 339 | omap_wdt_disable(wdev); |
7768a13c KS |
340 | omap_wdt_adjust_timeout(timer_margin); |
341 | ||
2817142f FB |
342 | wdev->omap_wdt_miscdev.parent = &pdev->dev; |
343 | wdev->omap_wdt_miscdev.minor = WATCHDOG_MINOR; | |
344 | wdev->omap_wdt_miscdev.name = "watchdog"; | |
345 | wdev->omap_wdt_miscdev.fops = &omap_wdt_fops; | |
346 | ||
347 | ret = misc_register(&(wdev->omap_wdt_miscdev)); | |
7768a13c KS |
348 | if (ret) |
349 | goto fail; | |
350 | ||
2817142f | 351 | pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec\n", |
9f69e3b0 | 352 | __raw_readl(wdev->base + OMAP_WATCHDOG_REV) & 0xFF, |
2817142f | 353 | timer_margin); |
7768a13c KS |
354 | |
355 | /* autogate OCP interface clock */ | |
9f69e3b0 | 356 | __raw_writel(0x01, wdev->base + OMAP_WATCHDOG_SYS_CONFIG); |
2817142f FB |
357 | |
358 | omap_wdt_dev = pdev; | |
359 | ||
7768a13c KS |
360 | return 0; |
361 | ||
362 | fail: | |
2817142f FB |
363 | if (wdev) { |
364 | platform_set_drvdata(pdev, NULL); | |
365 | if (wdev->armwdt_ck) | |
366 | clk_put(wdev->armwdt_ck); | |
367 | if (wdev->mpu_wdt_ick) | |
368 | clk_put(wdev->mpu_wdt_ick); | |
369 | if (wdev->mpu_wdt_fck) | |
370 | clk_put(wdev->mpu_wdt_fck); | |
9f69e3b0 | 371 | iounmap(wdev->base); |
2817142f FB |
372 | kfree(wdev); |
373 | } | |
374 | if (mem) { | |
375 | release_mem_region(res->start, res->end - res->start + 1); | |
376 | } | |
7768a13c KS |
377 | return ret; |
378 | } | |
379 | ||
380 | static void omap_wdt_shutdown(struct platform_device *pdev) | |
381 | { | |
2817142f FB |
382 | struct omap_wdt_dev *wdev; |
383 | wdev = platform_get_drvdata(pdev); | |
384 | ||
385 | if (wdev->omap_wdt_users) | |
386 | omap_wdt_disable(wdev); | |
7768a13c KS |
387 | } |
388 | ||
389 | static int omap_wdt_remove(struct platform_device *pdev) | |
390 | { | |
2817142f FB |
391 | struct omap_wdt_dev *wdev; |
392 | wdev = platform_get_drvdata(pdev); | |
393 | struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); | |
394 | ||
395 | if (!res) | |
396 | return -ENOENT; | |
397 | ||
398 | misc_deregister(&(wdev->omap_wdt_miscdev)); | |
399 | release_mem_region(res->start, res->end - res->start + 1); | |
400 | platform_set_drvdata(pdev, NULL); | |
401 | if (wdev->armwdt_ck) { | |
402 | clk_put(wdev->armwdt_ck); | |
403 | wdev->armwdt_ck = NULL; | |
404 | } | |
405 | if (wdev->mpu_wdt_ick) { | |
406 | clk_put(wdev->mpu_wdt_ick); | |
407 | wdev->mpu_wdt_ick = NULL; | |
408 | } | |
409 | if (wdev->mpu_wdt_fck) { | |
410 | clk_put(wdev->mpu_wdt_fck); | |
411 | wdev->mpu_wdt_fck = NULL; | |
412 | } | |
9f69e3b0 FB |
413 | iounmap(wdev->base); |
414 | ||
2817142f FB |
415 | kfree(wdev); |
416 | omap_wdt_dev = NULL; | |
7768a13c KS |
417 | return 0; |
418 | } | |
419 | ||
420 | #ifdef CONFIG_PM | |
421 | ||
422 | /* REVISIT ... not clear this is the best way to handle system suspend; and | |
423 | * it's very inappropriate for selective device suspend (e.g. suspending this | |
424 | * through sysfs rather than by stopping the watchdog daemon). Also, this | |
425 | * may not play well enough with NOWAYOUT... | |
426 | */ | |
427 | ||
428 | static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state) | |
429 | { | |
2817142f FB |
430 | struct omap_wdt_dev *wdev; |
431 | wdev = platform_get_drvdata(pdev); | |
432 | if (wdev->omap_wdt_users) | |
433 | omap_wdt_disable(wdev); | |
7768a13c KS |
434 | return 0; |
435 | } | |
436 | ||
437 | static int omap_wdt_resume(struct platform_device *pdev) | |
438 | { | |
2817142f FB |
439 | struct omap_wdt_dev *wdev; |
440 | wdev = platform_get_drvdata(pdev); | |
441 | if (wdev->omap_wdt_users) { | |
442 | omap_wdt_enable(wdev); | |
443 | omap_wdt_ping(wdev); | |
7768a13c KS |
444 | } |
445 | return 0; | |
446 | } | |
447 | ||
448 | #else | |
449 | #define omap_wdt_suspend NULL | |
450 | #define omap_wdt_resume NULL | |
451 | #endif | |
452 | ||
453 | static struct platform_driver omap_wdt_driver = { | |
454 | .probe = omap_wdt_probe, | |
455 | .remove = omap_wdt_remove, | |
456 | .shutdown = omap_wdt_shutdown, | |
457 | .suspend = omap_wdt_suspend, | |
458 | .resume = omap_wdt_resume, | |
459 | .driver = { | |
460 | .owner = THIS_MODULE, | |
461 | .name = "omap_wdt", | |
462 | }, | |
463 | }; | |
464 | ||
465 | static int __init omap_wdt_init(void) | |
466 | { | |
12b9df7d | 467 | spin_lock_init(&wdt_lock); |
7768a13c KS |
468 | return platform_driver_register(&omap_wdt_driver); |
469 | } | |
470 | ||
471 | static void __exit omap_wdt_exit(void) | |
472 | { | |
473 | platform_driver_unregister(&omap_wdt_driver); | |
474 | } | |
475 | ||
476 | module_init(omap_wdt_init); | |
477 | module_exit(omap_wdt_exit); | |
478 | ||
479 | MODULE_AUTHOR("George G. Davis"); | |
480 | MODULE_LICENSE("GPL"); | |
481 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | |
f37d193c | 482 | MODULE_ALIAS("platform:omap_wdt"); |