2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
16 * Copyright (C) 2006 infineon
17 * Copyright (C) 2007 John Crispin <blogic@openwrt.org>
21 #include <asm/uaccess.h>
22 #include <linux/errno.h>
23 #include <linux/proc_fs.h>
24 #include <linux/ioctl.h>
25 #include <linux/module.h>
26 #include <asm-mips/ifxmips/ifxmips_wdt.h>
27 #include <asm-mips/ifxmips/ifxmips.h>
28 #include <linux/platform_device.h>
30 #define DRVNAME "ifxmips_wdt"
32 // TODO remove magic numbers and weirdo macros
33 extern unsigned int ifxmips_get_fpi_hz (void);
35 static int ifxmips_wdt_inuse
= 0;
36 static int ifxmips_wdt_major
= 0;
39 ifxmips_wdt_enable (unsigned int timeout
)
41 unsigned int wdt_cr
= 0;
42 unsigned int wdt_reload
= 0;
43 unsigned int wdt_clkdiv
, wdt_pwl
, ffpi
;
46 /* clock divider & prewarning limit */
47 wdt_clkdiv
= 1 << (7 * IFXMIPS_BIU_WDT_CR_CLKDIV_GET(readl(IFXMIPS_BIU_WDT_CR
)));
48 wdt_pwl
= 0x8000 >> IFXMIPS_BIU_WDT_CR_PWL_GET(readl(IFXMIPS_BIU_WDT_CR
));
51 printk("WARNING FUNCTION CALL MISSING!!!");
52 //ffpi = cgu_get_io_region_clock();
53 printk("cpu clock = %d\n", ffpi
);
55 /* caculate reload value */
56 wdt_reload
= (timeout
* (ffpi
/ wdt_clkdiv
)) + wdt_pwl
;
58 printk(KERN_WARNING DRVNAME
": wdt_pwl=0x%x, wdt_clkdiv=%d, ffpi=%d, wdt_reload = 0x%x\n",
59 wdt_pwl
, wdt_clkdiv
, ffpi
, wdt_reload
);
61 if (wdt_reload
> 0xFFFF)
63 printk(KERN_WARNING DRVNAME
": timeout too large %d\n", timeout
);
68 /* Write first part of password access */
69 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1
), IFXMIPS_BIU_WDT_CR
);
71 wdt_cr
= readl(IFXMIPS_BIU_WDT_CR
);
72 wdt_cr
&= (!IFXMIPS_BIU_WDT_CR_PW_SET(0xff) &
73 !IFXMIPS_BIU_WDT_CR_PWL_SET(0x3) &
74 !IFXMIPS_BIU_WDT_CR_CLKDIV_SET(0x3) &
75 !IFXMIPS_BIU_WDT_CR_RELOAD_SET(0xffff));
77 wdt_cr
|= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2
) |
78 IFXMIPS_BIU_WDT_CR_PWL_SET(IFXMIPS_BIU_WDT_CR_PWL_GET(readl(IFXMIPS_BIU_WDT_CR
))) |
79 IFXMIPS_BIU_WDT_CR_CLKDIV_SET(IFXMIPS_BIU_WDT_CR_CLKDIV_GET(readl(IFXMIPS_BIU_WDT_CR
))) |
80 IFXMIPS_BIU_WDT_CR_RELOAD_SET(wdt_reload
) |
81 IFXMIPS_BIU_WDT_CR_GEN
);
83 writel(wdt_cr
, IFXMIPS_BIU_WDT_CR
);
85 printk("watchdog enabled\n");
92 ifxmips_wdt_disable (void)
94 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1
), IFXMIPS_BIU_WDT_CR
);
95 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2
), IFXMIPS_BIU_WDT_CR
);
97 printk("watchdog disabled\n");
100 /* passed LPEN or DSEN */
102 ifxmips_wdt_enable_feature (int en
, int type
)
104 unsigned int wdt_cr
= 0;
106 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1
), IFXMIPS_BIU_WDT_CR
);
108 wdt_cr
= readl(IFXMIPS_BIU_WDT_CR
);
112 wdt_cr
&= (~IFXMIPS_BIU_WDT_CR_PW_SET(0xff));
113 wdt_cr
|= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2
) | type
);
115 wdt_cr
&= (~IFXMIPS_BIU_WDT_CR_PW_SET(0xff) & ~type
);
116 wdt_cr
|= IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2
);
119 writel(wdt_cr
, IFXMIPS_BIU_WDT_CR
);
123 ifxmips_wdt_prewarning_limit (int pwl
)
125 unsigned int wdt_cr
= 0;
127 wdt_cr
= readl(IFXMIPS_BIU_WDT_CR
);
128 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1
), IFXMIPS_BIU_WDT_CR
);
130 wdt_cr
&= 0xf300ffff;
131 wdt_cr
|= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2
) | IFXMIPS_BIU_WDT_CR_PWL_SET(pwl
));
133 /* Set reload value in second password access */
134 writel(wdt_cr
, IFXMIPS_BIU_WDT_CR
);
138 ifxmips_wdt_set_clkdiv (int clkdiv
)
140 unsigned int wdt_cr
= 0;
142 wdt_cr
= readl(IFXMIPS_BIU_WDT_CR
);
143 writel(IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW1
), IFXMIPS_BIU_WDT_CR
);
145 wdt_cr
&= 0xfc00ffff;
146 wdt_cr
|= (IFXMIPS_BIU_WDT_CR_PW_SET(IFXMIPS_WDT_PW2
) | IFXMIPS_BIU_WDT_CR_CLKDIV_SET(clkdiv
));
148 /* Set reload value in second password access */
149 writel(wdt_cr
, IFXMIPS_BIU_WDT_CR
);
153 ifxmips_wdt_ioctl (struct inode
*inode
, struct file
*file
, unsigned int cmd
,
157 static int timeout
= -1;
158 unsigned int user_arg
;
160 if ((cmd
!= IFXMIPS_WDT_IOC_STOP
) && (cmd
!= IFXMIPS_WDT_IOC_PING
) && (cmd
!= IFXMIPS_WDT_IOC_GET_STATUS
))
162 if (copy_from_user((void *) &user_arg
, (void *) arg
, sizeof (int))){
170 case IFXMIPS_WDT_IOC_START
:
171 if ((result
= ifxmips_wdt_enable(user_arg
)) < 0)
177 case IFXMIPS_WDT_IOC_STOP
:
178 printk(KERN_INFO DRVNAME
": disable watch dog timer\n");
179 ifxmips_wdt_disable();
182 case IFXMIPS_WDT_IOC_PING
:
186 result
= ifxmips_wdt_enable(timeout
);
189 case IFXMIPS_WDT_IOC_GET_STATUS
:
190 user_arg
= readl(IFXMIPS_BIU_WDT_SR
);
191 copy_to_user((int*)arg
, (int*)&user_arg
, sizeof(int));
194 case IFXMIPS_WDT_IOC_SET_PWL
:
195 ifxmips_wdt_prewarning_limit(user_arg
);
198 case IFXMIPS_WDT_IOC_SET_DSEN
:
199 ifxmips_wdt_enable_feature(user_arg
, IFXMIPS_BIU_WDT_CR_DSEN
);
202 case IFXMIPS_WDT_IOC_SET_LPEN
:
203 ifxmips_wdt_enable_feature(user_arg
, IFXMIPS_BIU_WDT_CR_LPEN
);
206 case IFXMIPS_WDT_IOC_SET_CLKDIV
:
207 ifxmips_wdt_set_clkdiv(user_arg
);
211 printk(KERN_WARNING DRVNAME
": unknown watchdog iotcl\n");
219 ifxmips_wdt_open (struct inode
*inode
, struct file
*file
)
221 if (ifxmips_wdt_inuse
)
224 ifxmips_wdt_inuse
= 1;
230 ifxmips_wdt_release (struct inode
*inode
, struct file
*file
)
232 ifxmips_wdt_inuse
= 0;
238 ifxmips_wdt_register_proc_read (char *buf
, char **start
, off_t offset
, int count
,
239 int *eof
, void *data
)
243 len
+= sprintf (buf
+ len
, "IFXMIPS_BIU_WDT_PROC_READ\n");
244 len
+= sprintf (buf
+ len
, "IFXMIPS_BIU_WDT_CR(0x%08x) : 0x%08x\n",
245 (unsigned int)IFXMIPS_BIU_WDT_CR
, readl(IFXMIPS_BIU_WDT_CR
));
246 len
+= sprintf (buf
+ len
, "IFXMIPS_BIU_WDT_SR(0x%08x) : 0x%08x\n",
247 (unsigned int)IFXMIPS_BIU_WDT_SR
, readl(IFXMIPS_BIU_WDT_SR
));
254 static struct file_operations wdt_fops
= {
255 .owner
= THIS_MODULE
,
256 .ioctl
= ifxmips_wdt_ioctl
,
257 .open
= ifxmips_wdt_open
,
258 .release
= ifxmips_wdt_release
,
262 ifxmips_wdt_probe (struct platform_device
*pdev
)
264 ifxmips_wdt_major
= register_chrdev(0, "wdt", &wdt_fops
);
266 if (ifxmips_wdt_major
< 0)
268 printk("cannot register watchdog device\n");
273 create_proc_read_entry("ifxmips_wdt", 0, NULL
, ifxmips_wdt_register_proc_read
, NULL
);
275 printk("ifxmips watchdog loaded\n");
281 ifxmips_wdt_remove (struct platform_device
*pdev
)
283 unregister_chrdev(ifxmips_wdt_major
, "wdt");
284 remove_proc_entry(DRVNAME
, NULL
);
289 platform_driver ifxmips_wdt_driver
= {
290 .probe
= ifxmips_wdt_probe
,
291 .remove
= ifxmips_wdt_remove
,
294 .owner
= THIS_MODULE
,
299 ifxmips_wdt_init_module (void)
301 int ret
= platform_driver_register(&ifxmips_wdt_driver
);
303 printk(KERN_INFO DRVNAME
": Error registering platfom driver!");
308 ifxmips_wdt_cleanup_module (void)
310 platform_driver_unregister(&ifxmips_wdt_driver
);
313 module_init(ifxmips_wdt_init_module
);
314 module_exit(ifxmips_wdt_cleanup_module
);