diff options
-rw-r--r-- | drivers/watchdog/Kconfig | 4 | ||||
-rw-r--r-- | drivers/watchdog/mpc83xx_wdt.c | 80 |
2 files changed, 74 insertions, 10 deletions
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 48399e134c0d..93329620f447 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig | |||
@@ -696,8 +696,8 @@ config 8xx_WDT | |||
696 | depends on 8xx | 696 | depends on 8xx |
697 | 697 | ||
698 | config 83xx_WDT | 698 | config 83xx_WDT |
699 | tristate "MPC83xx Watchdog Timer" | 699 | tristate "MPC83xx/MPC86xx Watchdog Timer" |
700 | depends on PPC_83xx | 700 | depends on PPC_83xx || PPC_86xx |
701 | 701 | ||
702 | config MV64X60_WDT | 702 | config MV64X60_WDT |
703 | tristate "MV64X60 (Marvell Discovery) Watchdog Timer" | 703 | tristate "MV64X60 (Marvell Discovery) Watchdog Timer" |
diff --git a/drivers/watchdog/mpc83xx_wdt.c b/drivers/watchdog/mpc83xx_wdt.c index 5f1b7bff8f12..fa82ec99ba81 100644 --- a/drivers/watchdog/mpc83xx_wdt.c +++ b/drivers/watchdog/mpc83xx_wdt.c | |||
@@ -1,10 +1,12 @@ | |||
1 | /* | 1 | /* |
2 | * mpc83xx_wdt.c - MPC83xx watchdog userspace interface | 2 | * mpc83xx_wdt.c - MPC83xx/MPC86xx watchdog userspace interface |
3 | * | 3 | * |
4 | * Authors: Dave Updegraff <dave@cray.org> | 4 | * Authors: Dave Updegraff <dave@cray.org> |
5 | * Kumar Gala <galak@kernel.crashing.org> | 5 | * Kumar Gala <galak@kernel.crashing.org> |
6 | * Attribution: from 83xx_wst: Florian Schirmer <jolt@tuxbox.org> | 6 | * Attribution: from 83xx_wst: Florian Schirmer <jolt@tuxbox.org> |
7 | * ..and from sc520_wdt | 7 | * ..and from sc520_wdt |
8 | * Copyright (c) 2008 MontaVista Software, Inc. | ||
9 | * Anton Vorontsov <avorontsov@ru.mvista.com> | ||
8 | * | 10 | * |
9 | * Note: it appears that you can only actually ENABLE or DISABLE the thing | 11 | * Note: it appears that you can only actually ENABLE or DISABLE the thing |
10 | * once after POR. Once enabled, you cannot disable, and vice versa. | 12 | * once after POR. Once enabled, you cannot disable, and vice versa. |
@@ -18,6 +20,7 @@ | |||
18 | #include <linux/fs.h> | 20 | #include <linux/fs.h> |
19 | #include <linux/init.h> | 21 | #include <linux/init.h> |
20 | #include <linux/kernel.h> | 22 | #include <linux/kernel.h> |
23 | #include <linux/timer.h> | ||
21 | #include <linux/miscdevice.h> | 24 | #include <linux/miscdevice.h> |
22 | #include <linux/of_platform.h> | 25 | #include <linux/of_platform.h> |
23 | #include <linux/module.h> | 26 | #include <linux/module.h> |
@@ -39,6 +42,11 @@ struct mpc83xx_wdt { | |||
39 | u8 res2[0xF0]; | 42 | u8 res2[0xF0]; |
40 | }; | 43 | }; |
41 | 44 | ||
45 | struct mpc83xx_wdt_type { | ||
46 | int prescaler; | ||
47 | bool hw_enabled; | ||
48 | }; | ||
49 | |||
42 | static struct mpc83xx_wdt __iomem *wd_base; | 50 | static struct mpc83xx_wdt __iomem *wd_base; |
43 | 51 | ||
44 | static u16 timeout = 0xffff; | 52 | static u16 timeout = 0xffff; |
@@ -51,6 +59,11 @@ module_param(reset, bool, 0); | |||
51 | MODULE_PARM_DESC(reset, | 59 | MODULE_PARM_DESC(reset, |
52 | "Watchdog Interrupt/Reset Mode. 0 = interrupt, 1 = reset"); | 60 | "Watchdog Interrupt/Reset Mode. 0 = interrupt, 1 = reset"); |
53 | 61 | ||
62 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
63 | module_param(nowayout, int, 0); | ||
64 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started " | ||
65 | "(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
66 | |||
54 | /* | 67 | /* |
55 | * We always prescale, but if someone really doesn't want to they can set this | 68 | * We always prescale, but if someone really doesn't want to they can set this |
56 | * to 0 | 69 | * to 0 |
@@ -70,6 +83,22 @@ static void mpc83xx_wdt_keepalive(void) | |||
70 | spin_unlock(&wdt_spinlock); | 83 | spin_unlock(&wdt_spinlock); |
71 | } | 84 | } |
72 | 85 | ||
86 | static void mpc83xx_wdt_timer_ping(unsigned long arg); | ||
87 | static DEFINE_TIMER(wdt_timer, mpc83xx_wdt_timer_ping, 0, 0); | ||
88 | |||
89 | static void mpc83xx_wdt_timer_ping(unsigned long arg) | ||
90 | { | ||
91 | mpc83xx_wdt_keepalive(); | ||
92 | /* We're pinging it twice faster than needed, just to be sure. */ | ||
93 | mod_timer(&wdt_timer, jiffies + HZ * timeout_sec / 2); | ||
94 | } | ||
95 | |||
96 | static void mpc83xx_wdt_pr_warn(const char *msg) | ||
97 | { | ||
98 | pr_crit("mpc83xx_wdt: %s, expect the %s soon!\n", msg, | ||
99 | reset ? "reset" : "machine check exception"); | ||
100 | } | ||
101 | |||
73 | static ssize_t mpc83xx_wdt_write(struct file *file, const char __user *buf, | 102 | static ssize_t mpc83xx_wdt_write(struct file *file, const char __user *buf, |
74 | size_t count, loff_t *ppos) | 103 | size_t count, loff_t *ppos) |
75 | { | 104 | { |
@@ -85,7 +114,8 @@ static int mpc83xx_wdt_open(struct inode *inode, struct file *file) | |||
85 | return -EBUSY; | 114 | return -EBUSY; |
86 | 115 | ||
87 | /* Once we start the watchdog we can't stop it */ | 116 | /* Once we start the watchdog we can't stop it */ |
88 | __module_get(THIS_MODULE); | 117 | if (nowayout) |
118 | __module_get(THIS_MODULE); | ||
89 | 119 | ||
90 | /* Good, fire up the show */ | 120 | /* Good, fire up the show */ |
91 | if (prescale) | 121 | if (prescale) |
@@ -97,13 +127,17 @@ static int mpc83xx_wdt_open(struct inode *inode, struct file *file) | |||
97 | 127 | ||
98 | out_be32(&wd_base->swcrr, tmp); | 128 | out_be32(&wd_base->swcrr, tmp); |
99 | 129 | ||
130 | del_timer_sync(&wdt_timer); | ||
131 | |||
100 | return nonseekable_open(inode, file); | 132 | return nonseekable_open(inode, file); |
101 | } | 133 | } |
102 | 134 | ||
103 | static int mpc83xx_wdt_release(struct inode *inode, struct file *file) | 135 | static int mpc83xx_wdt_release(struct inode *inode, struct file *file) |
104 | { | 136 | { |
105 | printk(KERN_CRIT "Unexpected close, not stopping watchdog!\n"); | 137 | if (!nowayout) |
106 | mpc83xx_wdt_keepalive(); | 138 | mpc83xx_wdt_timer_ping(0); |
139 | else | ||
140 | mpc83xx_wdt_pr_warn("watchdog closed"); | ||
107 | clear_bit(0, &wdt_is_open); | 141 | clear_bit(0, &wdt_is_open); |
108 | return 0; | 142 | return 0; |
109 | } | 143 | } |
@@ -154,15 +188,25 @@ static int __devinit mpc83xx_wdt_probe(struct of_device *ofdev, | |||
154 | const struct of_device_id *match) | 188 | const struct of_device_id *match) |
155 | { | 189 | { |
156 | int ret; | 190 | int ret; |
191 | struct device_node *np = ofdev->node; | ||
192 | struct mpc83xx_wdt_type *wdt_type = match->data; | ||
157 | u32 freq = fsl_get_sys_freq(); | 193 | u32 freq = fsl_get_sys_freq(); |
194 | bool enabled; | ||
158 | 195 | ||
159 | if (!freq || freq == -1) | 196 | if (!freq || freq == -1) |
160 | return -EINVAL; | 197 | return -EINVAL; |
161 | 198 | ||
162 | wd_base = of_iomap(ofdev->node, 0); | 199 | wd_base = of_iomap(np, 0); |
163 | if (!wd_base) | 200 | if (!wd_base) |
164 | return -ENOMEM; | 201 | return -ENOMEM; |
165 | 202 | ||
203 | enabled = in_be32(&wd_base->swcrr) & SWCRR_SWEN; | ||
204 | if (!enabled && wdt_type->hw_enabled) { | ||
205 | pr_info("mpc83xx_wdt: could not be enabled in software\n"); | ||
206 | ret = -ENOSYS; | ||
207 | goto err_unmap; | ||
208 | } | ||
209 | |||
166 | ret = misc_register(&mpc83xx_wdt_miscdev); | 210 | ret = misc_register(&mpc83xx_wdt_miscdev); |
167 | if (ret) { | 211 | if (ret) { |
168 | pr_err("cannot register miscdev on minor=%d (err=%d)\n", | 212 | pr_err("cannot register miscdev on minor=%d (err=%d)\n", |
@@ -172,13 +216,21 @@ static int __devinit mpc83xx_wdt_probe(struct of_device *ofdev, | |||
172 | 216 | ||
173 | /* Calculate the timeout in seconds */ | 217 | /* Calculate the timeout in seconds */ |
174 | if (prescale) | 218 | if (prescale) |
175 | timeout_sec = (timeout * 0x10000) / freq; | 219 | timeout_sec = (timeout * wdt_type->prescaler) / freq; |
176 | else | 220 | else |
177 | timeout_sec = timeout / freq; | 221 | timeout_sec = timeout / freq; |
178 | 222 | ||
179 | pr_info("WDT driver for MPC83xx initialized. mode:%s timeout=%d " | 223 | pr_info("WDT driver for MPC83xx initialized. mode:%s timeout=%d " |
180 | "(%d seconds)\n", reset ? "reset" : "interrupt", timeout, | 224 | "(%d seconds)\n", reset ? "reset" : "interrupt", timeout, |
181 | timeout_sec); | 225 | timeout_sec); |
226 | |||
227 | /* | ||
228 | * If the watchdog was previously enabled or we're running on | ||
229 | * MPC86xx, we should ping the wdt from the kernel until the | ||
230 | * userspace handles it. | ||
231 | */ | ||
232 | if (enabled) | ||
233 | mpc83xx_wdt_timer_ping(0); | ||
182 | return 0; | 234 | return 0; |
183 | err_unmap: | 235 | err_unmap: |
184 | iounmap(wd_base); | 236 | iounmap(wd_base); |
@@ -187,6 +239,8 @@ err_unmap: | |||
187 | 239 | ||
188 | static int __devexit mpc83xx_wdt_remove(struct of_device *ofdev) | 240 | static int __devexit mpc83xx_wdt_remove(struct of_device *ofdev) |
189 | { | 241 | { |
242 | mpc83xx_wdt_pr_warn("watchdog removed"); | ||
243 | del_timer_sync(&wdt_timer); | ||
190 | misc_deregister(&mpc83xx_wdt_miscdev); | 244 | misc_deregister(&mpc83xx_wdt_miscdev); |
191 | iounmap(wd_base); | 245 | iounmap(wd_base); |
192 | 246 | ||
@@ -196,6 +250,16 @@ static int __devexit mpc83xx_wdt_remove(struct of_device *ofdev) | |||
196 | static const struct of_device_id mpc83xx_wdt_match[] = { | 250 | static const struct of_device_id mpc83xx_wdt_match[] = { |
197 | { | 251 | { |
198 | .compatible = "mpc83xx_wdt", | 252 | .compatible = "mpc83xx_wdt", |
253 | .data = &(struct mpc83xx_wdt_type) { | ||
254 | .prescaler = 0x10000, | ||
255 | }, | ||
256 | }, | ||
257 | { | ||
258 | .compatible = "fsl,mpc8610-wdt", | ||
259 | .data = &(struct mpc83xx_wdt_type) { | ||
260 | .prescaler = 0x10000, | ||
261 | .hw_enabled = true, | ||
262 | }, | ||
199 | }, | 263 | }, |
200 | {}, | 264 | {}, |
201 | }; | 265 | }; |
@@ -221,10 +285,10 @@ static void __exit mpc83xx_wdt_exit(void) | |||
221 | of_unregister_platform_driver(&mpc83xx_wdt_driver); | 285 | of_unregister_platform_driver(&mpc83xx_wdt_driver); |
222 | } | 286 | } |
223 | 287 | ||
224 | module_init(mpc83xx_wdt_init); | 288 | subsys_initcall(mpc83xx_wdt_init); |
225 | module_exit(mpc83xx_wdt_exit); | 289 | module_exit(mpc83xx_wdt_exit); |
226 | 290 | ||
227 | MODULE_AUTHOR("Dave Updegraff, Kumar Gala"); | 291 | MODULE_AUTHOR("Dave Updegraff, Kumar Gala"); |
228 | MODULE_DESCRIPTION("Driver for watchdog timer in MPC83xx uProcessor"); | 292 | MODULE_DESCRIPTION("Driver for watchdog timer in MPC83xx/MPC86xx uProcessors"); |
229 | MODULE_LICENSE("GPL"); | 293 | MODULE_LICENSE("GPL"); |
230 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | 294 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |