diff options
author | Len Brown <len.brown@intel.com> | 2005-09-08 01:45:47 -0400 |
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committer | Len Brown <len.brown@intel.com> | 2005-09-08 01:45:47 -0400 |
commit | 64e47488c913ac704d465a6af86a26786d1412a5 (patch) | |
tree | d3b0148592963dcde26e4bb35ddfec8b1eaf8e23 /drivers/char/watchdog/booke_wdt.c | |
parent | 4a35a46bf1cda4737c428380d1db5d15e2590d18 (diff) | |
parent | caf39e87cc1182f7dae84eefc43ca14d54c78ef9 (diff) |
Merge linux-2.6 with linux-acpi-2.6
Diffstat (limited to 'drivers/char/watchdog/booke_wdt.c')
-rw-r--r-- | drivers/char/watchdog/booke_wdt.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/char/watchdog/booke_wdt.c b/drivers/char/watchdog/booke_wdt.c new file mode 100644 index 000000000000..abc30cca6645 --- /dev/null +++ b/drivers/char/watchdog/booke_wdt.c | |||
@@ -0,0 +1,192 @@ | |||
1 | /* | ||
2 | * drivers/char/watchdog/booke_wdt.c | ||
3 | * | ||
4 | * Watchdog timer for PowerPC Book-E systems | ||
5 | * | ||
6 | * Author: Matthew McClintock | ||
7 | * Maintainer: Kumar Gala <kumar.gala@freescale.com> | ||
8 | * | ||
9 | * Copyright 2005 Freescale Semiconductor Inc. | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or modify it | ||
12 | * under the terms of the GNU General Public License as published by the | ||
13 | * Free Software Foundation; either version 2 of the License, or (at your | ||
14 | * option) any later version. | ||
15 | */ | ||
16 | |||
17 | #include <linux/config.h> | ||
18 | #include <linux/module.h> | ||
19 | #include <linux/fs.h> | ||
20 | #include <linux/miscdevice.h> | ||
21 | #include <linux/notifier.h> | ||
22 | #include <linux/watchdog.h> | ||
23 | |||
24 | #include <asm/reg_booke.h> | ||
25 | #include <asm/uaccess.h> | ||
26 | #include <asm/system.h> | ||
27 | |||
28 | /* If the kernel parameter wdt_enable=1, the watchdog will be enabled at boot. | ||
29 | * Also, the wdt_period sets the watchdog timer period timeout. | ||
30 | * For E500 cpus the wdt_period sets which bit changing from 0->1 will | ||
31 | * trigger a watchog timeout. This watchdog timeout will occur 3 times, the | ||
32 | * first time nothing will happen, the second time a watchdog exception will | ||
33 | * occur, and the final time the board will reset. | ||
34 | */ | ||
35 | |||
36 | #ifdef CONFIG_FSL_BOOKE | ||
37 | #define WDT_PERIOD_DEFAULT 63 /* Ex. wdt_period=28 bus=333Mhz , reset=~40sec */ | ||
38 | #else | ||
39 | #define WDT_PERIOD_DEFAULT 4 /* Refer to the PPC40x and PPC4xx manuals */ | ||
40 | #endif /* for timing information */ | ||
41 | |||
42 | u32 booke_wdt_enabled = 0; | ||
43 | u32 booke_wdt_period = WDT_PERIOD_DEFAULT; | ||
44 | |||
45 | #ifdef CONFIG_FSL_BOOKE | ||
46 | #define WDTP(x) ((((63-x)&0x3)<<30)|(((63-x)&0x3c)<<15)) | ||
47 | #else | ||
48 | #define WDTP(x) (TCR_WP(x)) | ||
49 | #endif | ||
50 | |||
51 | /* | ||
52 | * booke_wdt_enable: | ||
53 | */ | ||
54 | static __inline__ void booke_wdt_enable(void) | ||
55 | { | ||
56 | u32 val; | ||
57 | |||
58 | val = mfspr(SPRN_TCR); | ||
59 | val |= (TCR_WIE|TCR_WRC(WRC_CHIP)|WDTP(booke_wdt_period)); | ||
60 | |||
61 | mtspr(SPRN_TCR, val); | ||
62 | } | ||
63 | |||
64 | /* | ||
65 | * booke_wdt_ping: | ||
66 | */ | ||
67 | static __inline__ void booke_wdt_ping(void) | ||
68 | { | ||
69 | mtspr(SPRN_TSR, TSR_ENW|TSR_WIS); | ||
70 | } | ||
71 | |||
72 | /* | ||
73 | * booke_wdt_write: | ||
74 | */ | ||
75 | static ssize_t booke_wdt_write (struct file *file, const char *buf, | ||
76 | size_t count, loff_t *ppos) | ||
77 | { | ||
78 | booke_wdt_ping(); | ||
79 | return count; | ||
80 | } | ||
81 | |||
82 | static struct watchdog_info ident = { | ||
83 | .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, | ||
84 | .firmware_version = 0, | ||
85 | .identity = "PowerPC Book-E Watchdog", | ||
86 | }; | ||
87 | |||
88 | /* | ||
89 | * booke_wdt_ioctl: | ||
90 | */ | ||
91 | static int booke_wdt_ioctl (struct inode *inode, struct file *file, | ||
92 | unsigned int cmd, unsigned long arg) | ||
93 | { | ||
94 | u32 tmp = 0; | ||
95 | |||
96 | switch (cmd) { | ||
97 | case WDIOC_GETSUPPORT: | ||
98 | if (copy_to_user ((struct watchdog_info *) arg, &ident, | ||
99 | sizeof(struct watchdog_info))) | ||
100 | return -EFAULT; | ||
101 | case WDIOC_GETSTATUS: | ||
102 | return put_user(ident.options, (u32 *) arg); | ||
103 | case WDIOC_GETBOOTSTATUS: | ||
104 | /* XXX: something is clearing TSR */ | ||
105 | tmp = mfspr(SPRN_TSR) & TSR_WRS(3); | ||
106 | /* returns 1 if last reset was caused by the WDT */ | ||
107 | return (tmp ? 1 : 0); | ||
108 | case WDIOC_KEEPALIVE: | ||
109 | booke_wdt_ping(); | ||
110 | return 0; | ||
111 | case WDIOC_SETTIMEOUT: | ||
112 | if (get_user(booke_wdt_period, (u32 *) arg)) | ||
113 | return -EFAULT; | ||
114 | mtspr(SPRN_TCR, (mfspr(SPRN_TCR)&~WDTP(0))|WDTP(booke_wdt_period)); | ||
115 | return 0; | ||
116 | case WDIOC_GETTIMEOUT: | ||
117 | return put_user(booke_wdt_period, (u32 *) arg); | ||
118 | case WDIOC_SETOPTIONS: | ||
119 | if (get_user(tmp, (u32 *) arg)) | ||
120 | return -EINVAL; | ||
121 | if (tmp == WDIOS_ENABLECARD) { | ||
122 | booke_wdt_ping(); | ||
123 | break; | ||
124 | } else | ||
125 | return -EINVAL; | ||
126 | return 0; | ||
127 | default: | ||
128 | return -ENOIOCTLCMD; | ||
129 | } | ||
130 | |||
131 | return 0; | ||
132 | } | ||
133 | /* | ||
134 | * booke_wdt_open: | ||
135 | */ | ||
136 | static int booke_wdt_open (struct inode *inode, struct file *file) | ||
137 | { | ||
138 | if (booke_wdt_enabled == 0) { | ||
139 | booke_wdt_enabled = 1; | ||
140 | booke_wdt_enable(); | ||
141 | printk (KERN_INFO "PowerPC Book-E Watchdog Timer Enabled (wdt_period=%d)\n", | ||
142 | booke_wdt_period); | ||
143 | } | ||
144 | |||
145 | return 0; | ||
146 | } | ||
147 | |||
148 | static struct file_operations booke_wdt_fops = { | ||
149 | .owner = THIS_MODULE, | ||
150 | .llseek = no_llseek, | ||
151 | .write = booke_wdt_write, | ||
152 | .ioctl = booke_wdt_ioctl, | ||
153 | .open = booke_wdt_open, | ||
154 | }; | ||
155 | |||
156 | static struct miscdevice booke_wdt_miscdev = { | ||
157 | .minor = WATCHDOG_MINOR, | ||
158 | .name = "watchdog", | ||
159 | .fops = &booke_wdt_fops, | ||
160 | }; | ||
161 | |||
162 | static void __exit booke_wdt_exit(void) | ||
163 | { | ||
164 | misc_deregister(&booke_wdt_miscdev); | ||
165 | } | ||
166 | |||
167 | /* | ||
168 | * booke_wdt_init: | ||
169 | */ | ||
170 | static int __init booke_wdt_init(void) | ||
171 | { | ||
172 | int ret = 0; | ||
173 | |||
174 | printk (KERN_INFO "PowerPC Book-E Watchdog Timer Loaded\n"); | ||
175 | ident.firmware_version = cpu_specs[0].pvr_value; | ||
176 | |||
177 | ret = misc_register(&booke_wdt_miscdev); | ||
178 | if (ret) { | ||
179 | printk (KERN_CRIT "Cannot register miscdev on minor=%d (err=%d)\n", | ||
180 | WATCHDOG_MINOR, ret); | ||
181 | return ret; | ||
182 | } | ||
183 | |||
184 | if (booke_wdt_enabled == 1) { | ||
185 | printk (KERN_INFO "PowerPC Book-E Watchdog Timer Enabled (wdt_period=%d)\n", | ||
186 | booke_wdt_period); | ||
187 | booke_wdt_enable(); | ||
188 | } | ||
189 | |||
190 | return ret; | ||
191 | } | ||
192 | device_initcall(booke_wdt_init); | ||