[MIPS] Add MTD device support for Cobalt
[linux-2.6] / drivers / char / watchdog / ibmasr.c
1 /*
2  * IBM Automatic Server Restart driver.
3  *
4  * Copyright (c) 2005 Andrey Panin <pazke@donpac.ru>
5  *
6  * Based on driver written by Pete Reynolds.
7  * Copyright (c) IBM Corporation, 1998-2004.
8  *
9  * This software may be used and distributed according to the terms
10  * of the GNU Public License, incorporated herein by reference.
11  */
12
13 #include <linux/fs.h>
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/pci.h>
18 #include <linux/timer.h>
19 #include <linux/miscdevice.h>
20 #include <linux/watchdog.h>
21 #include <linux/dmi.h>
22
23 #include <asm/io.h>
24 #include <asm/uaccess.h>
25
26
27 enum {
28         ASMTYPE_UNKNOWN,
29         ASMTYPE_TOPAZ,
30         ASMTYPE_JASPER,
31         ASMTYPE_PEARL,
32         ASMTYPE_JUNIPER,
33         ASMTYPE_SPRUCE,
34 };
35
36 #define PFX "ibmasr: "
37
38 #define TOPAZ_ASR_REG_OFFSET    4
39 #define TOPAZ_ASR_TOGGLE        0x40
40 #define TOPAZ_ASR_DISABLE       0x80
41
42 /* PEARL ASR S/W REGISTER SUPERIO PORT ADDRESSES */
43 #define PEARL_BASE      0xe04
44 #define PEARL_WRITE     0xe06
45 #define PEARL_READ      0xe07
46
47 #define PEARL_ASR_DISABLE_MASK  0x80    /* bit 7: disable = 1, enable = 0 */
48 #define PEARL_ASR_TOGGLE_MASK   0x40    /* bit 6: 0, then 1, then 0 */
49
50 /* JASPER OFFSET FROM SIO BASE ADDR TO ASR S/W REGISTERS. */
51 #define JASPER_ASR_REG_OFFSET   0x38
52
53 #define JASPER_ASR_DISABLE_MASK 0x01    /* bit 0: disable = 1, enable = 0 */
54 #define JASPER_ASR_TOGGLE_MASK  0x02    /* bit 1: 0, then 1, then 0 */
55
56 #define JUNIPER_BASE_ADDRESS    0x54b   /* Base address of Juniper ASR */
57 #define JUNIPER_ASR_DISABLE_MASK 0x01   /* bit 0: disable = 1 enable = 0 */
58 #define JUNIPER_ASR_TOGGLE_MASK 0x02    /* bit 1: 0, then 1, then 0 */
59
60 #define SPRUCE_BASE_ADDRESS     0x118e  /* Base address of Spruce ASR */
61 #define SPRUCE_ASR_DISABLE_MASK 0x01    /* bit 1: disable = 1 enable = 0 */
62 #define SPRUCE_ASR_TOGGLE_MASK  0x02    /* bit 0: 0, then 1, then 0 */
63
64
65 static int nowayout = WATCHDOG_NOWAYOUT;
66
67 static unsigned long asr_is_open;
68 static char asr_expect_close;
69
70 static unsigned int asr_type, asr_base, asr_length;
71 static unsigned int asr_read_addr, asr_write_addr;
72 static unsigned char asr_toggle_mask, asr_disable_mask;
73
74 static void asr_toggle(void)
75 {
76         unsigned char reg = inb(asr_read_addr);
77
78         outb(reg & ~asr_toggle_mask, asr_write_addr);
79         reg = inb(asr_read_addr);
80
81         outb(reg | asr_toggle_mask, asr_write_addr);
82         reg = inb(asr_read_addr);
83
84         outb(reg & ~asr_toggle_mask, asr_write_addr);
85         reg = inb(asr_read_addr);
86 }
87
88 static void asr_enable(void)
89 {
90         unsigned char reg;
91
92         if (asr_type == ASMTYPE_TOPAZ) {
93                 /* asr_write_addr == asr_read_addr */
94                 reg = inb(asr_read_addr);
95                 outb(reg & ~(TOPAZ_ASR_TOGGLE | TOPAZ_ASR_DISABLE),
96                      asr_read_addr);
97         } else {
98                 /*
99                  * First make sure the hardware timer is reset by toggling
100                  * ASR hardware timer line.
101                  */
102                 asr_toggle();
103
104                 reg = inb(asr_read_addr);
105                 outb(reg & ~asr_disable_mask, asr_write_addr);
106         }
107         reg = inb(asr_read_addr);
108 }
109
110 static void asr_disable(void)
111 {
112         unsigned char reg = inb(asr_read_addr);
113
114         if (asr_type == ASMTYPE_TOPAZ)
115                 /* asr_write_addr == asr_read_addr */
116                 outb(reg | TOPAZ_ASR_TOGGLE | TOPAZ_ASR_DISABLE,
117                      asr_read_addr);
118         else {
119                 outb(reg | asr_toggle_mask, asr_write_addr);
120                 reg = inb(asr_read_addr);
121
122                 outb(reg | asr_disable_mask, asr_write_addr);
123         }
124         reg = inb(asr_read_addr);
125 }
126
127 static int __init asr_get_base_address(void)
128 {
129         unsigned char low, high;
130         const char *type = "";
131
132         asr_length = 1;
133
134         switch (asr_type) {
135         case ASMTYPE_TOPAZ:
136                 /* SELECT SuperIO CHIP FOR QUERYING (WRITE 0x07 TO BOTH 0x2E and 0x2F) */
137                 outb(0x07, 0x2e);
138                 outb(0x07, 0x2f);
139
140                 /* SELECT AND READ THE HIGH-NIBBLE OF THE GPIO BASE ADDRESS */
141                 outb(0x60, 0x2e);
142                 high = inb(0x2f);
143
144                 /* SELECT AND READ THE LOW-NIBBLE OF THE GPIO BASE ADDRESS */
145                 outb(0x61, 0x2e);
146                 low = inb(0x2f);
147
148                 asr_base = (high << 16) | low;
149                 asr_read_addr = asr_write_addr =
150                         asr_base + TOPAZ_ASR_REG_OFFSET;
151                 asr_length = 5;
152
153                 break;
154
155         case ASMTYPE_JASPER:
156                 type = "Jaspers ";
157
158                 /* FIXME: need to use pci_config_lock here, but it's not exported */
159
160 /*              spin_lock_irqsave(&pci_config_lock, flags);*/
161
162                 /* Select the SuperIO chip in the PCI I/O port register */
163                 outl(0x8000f858, 0xcf8);
164
165                 /*
166                  * Read the base address for the SuperIO chip.
167                  * Only the lower 16 bits are valid, but the address is word
168                  * aligned so the last bit must be masked off.
169                  */
170                 asr_base = inl(0xcfc) & 0xfffe;
171
172 /*              spin_unlock_irqrestore(&pci_config_lock, flags);*/
173
174                 asr_read_addr = asr_write_addr =
175                         asr_base + JASPER_ASR_REG_OFFSET;
176                 asr_toggle_mask = JASPER_ASR_TOGGLE_MASK;
177                 asr_disable_mask = JASPER_ASR_DISABLE_MASK;
178                 asr_length = JASPER_ASR_REG_OFFSET + 1;
179
180                 break;
181
182         case ASMTYPE_PEARL:
183                 type = "Pearls ";
184                 asr_base = PEARL_BASE;
185                 asr_read_addr = PEARL_READ;
186                 asr_write_addr = PEARL_WRITE;
187                 asr_toggle_mask = PEARL_ASR_TOGGLE_MASK;
188                 asr_disable_mask = PEARL_ASR_DISABLE_MASK;
189                 asr_length = 4;
190                 break;
191
192         case ASMTYPE_JUNIPER:
193                 type = "Junipers ";
194                 asr_base = JUNIPER_BASE_ADDRESS;
195                 asr_read_addr = asr_write_addr = asr_base;
196                 asr_toggle_mask = JUNIPER_ASR_TOGGLE_MASK;
197                 asr_disable_mask = JUNIPER_ASR_DISABLE_MASK;
198                 break;
199
200         case ASMTYPE_SPRUCE:
201                 type = "Spruce's ";
202                 asr_base = SPRUCE_BASE_ADDRESS;
203                 asr_read_addr = asr_write_addr = asr_base;
204                 asr_toggle_mask = SPRUCE_ASR_TOGGLE_MASK;
205                 asr_disable_mask = SPRUCE_ASR_DISABLE_MASK;
206                 break;
207         }
208
209         if (!request_region(asr_base, asr_length, "ibmasr")) {
210                 printk(KERN_ERR PFX "address %#x already in use\n",
211                         asr_base);
212                 return -EBUSY;
213         }
214
215         printk(KERN_INFO PFX "found %sASR @ addr %#x\n", type, asr_base);
216
217         return 0;
218 }
219
220
221 static ssize_t asr_write(struct file *file, const char __user *buf,
222                          size_t count, loff_t *ppos)
223 {
224         if (count) {
225                 if (!nowayout) {
226                         size_t i;
227
228                         /* In case it was set long ago */
229                         asr_expect_close = 0;
230
231                         for (i = 0; i != count; i++) {
232                                 char c;
233                                 if (get_user(c, buf + i))
234                                         return -EFAULT;
235                                 if (c == 'V')
236                                         asr_expect_close = 42;
237                         }
238                 }
239                 asr_toggle();
240         }
241         return count;
242 }
243
244 static int asr_ioctl(struct inode *inode, struct file *file,
245                      unsigned int cmd, unsigned long arg)
246 {
247         static const struct watchdog_info ident = {
248                 .options =      WDIOF_KEEPALIVEPING | 
249                                 WDIOF_MAGICCLOSE,
250                 .identity =     "IBM ASR"
251         };
252         void __user *argp = (void __user *)arg;
253         int __user *p = argp;
254         int heartbeat;
255
256         switch (cmd) {
257                 case WDIOC_GETSUPPORT:
258                         return copy_to_user(argp, &ident, sizeof(ident)) ?
259                                 -EFAULT : 0;
260
261                 case WDIOC_GETSTATUS:
262                 case WDIOC_GETBOOTSTATUS:
263                         return put_user(0, p);
264
265                 case WDIOC_KEEPALIVE:
266                         asr_toggle();
267                         return 0;
268
269                 /*
270                  * The hardware has a fixed timeout value, so no WDIOC_SETTIMEOUT
271                  * and WDIOC_GETTIMEOUT always returns 256.
272                  */
273                 case WDIOC_GETTIMEOUT:
274                         heartbeat = 256;
275                         return put_user(heartbeat, p);
276
277                 case WDIOC_SETOPTIONS: {
278                         int new_options, retval = -EINVAL;
279
280                         if (get_user(new_options, p))
281                                 return -EFAULT;
282
283                         if (new_options & WDIOS_DISABLECARD) {
284                                 asr_disable();
285                                 retval = 0;
286                         }
287
288                         if (new_options & WDIOS_ENABLECARD) {
289                                 asr_enable();
290                                 asr_toggle();
291                                 retval = 0;
292                         }
293
294                         return retval;
295                 }
296         }
297
298         return -ENOTTY;
299 }
300
301 static int asr_open(struct inode *inode, struct file *file)
302 {
303         if(test_and_set_bit(0, &asr_is_open))
304                 return -EBUSY;
305
306         asr_toggle();
307         asr_enable();
308
309         return nonseekable_open(inode, file);
310 }
311
312 static int asr_release(struct inode *inode, struct file *file)
313 {
314         if (asr_expect_close == 42)
315                 asr_disable();
316         else {
317                 printk(KERN_CRIT PFX "unexpected close, not stopping watchdog!\n");
318                 asr_toggle();
319         }
320         clear_bit(0, &asr_is_open);
321         asr_expect_close = 0;
322         return 0;
323 }
324
325 static const struct file_operations asr_fops = {
326         .owner =        THIS_MODULE,
327         .llseek =       no_llseek,
328         .write =        asr_write,
329         .ioctl =        asr_ioctl,
330         .open =         asr_open,
331         .release =      asr_release,
332 };
333
334 static struct miscdevice asr_miscdev = {
335         .minor =        WATCHDOG_MINOR,
336         .name =         "watchdog",
337         .fops =         &asr_fops,
338 };
339
340
341 struct ibmasr_id {
342         const char *desc;
343         int type;
344 };
345
346 static struct ibmasr_id __initdata ibmasr_id_table[] = {
347         { "IBM Automatic Server Restart - eserver xSeries 220", ASMTYPE_TOPAZ },
348         { "IBM Automatic Server Restart - Machine Type 8673", ASMTYPE_PEARL },
349         { "IBM Automatic Server Restart - Machine Type 8480", ASMTYPE_JASPER },
350         { "IBM Automatic Server Restart - Machine Type 8482", ASMTYPE_JUNIPER },
351         { "IBM Automatic Server Restart - Machine Type 8648", ASMTYPE_SPRUCE },
352         { NULL }
353 };
354
355 static int __init ibmasr_init(void)
356 {
357         struct ibmasr_id *id;
358         int rc;
359
360         for (id = ibmasr_id_table; id->desc; id++) {
361                 if (dmi_find_device(DMI_DEV_TYPE_OTHER, id->desc, NULL)) {
362                         asr_type = id->type;
363                         break;
364                 }
365         }
366
367         if (!asr_type)
368                 return -ENODEV;
369
370         rc = misc_register(&asr_miscdev);
371         if (rc < 0) {
372                 printk(KERN_ERR PFX "failed to register misc device\n");
373                 return rc;
374         }
375
376         rc = asr_get_base_address();
377         if (rc) {
378                 misc_deregister(&asr_miscdev);
379                 return rc;
380         }
381
382         return 0;
383 }
384
385 static void __exit ibmasr_exit(void)
386 {
387         if (!nowayout)
388                 asr_disable();
389
390         misc_deregister(&asr_miscdev);
391
392         release_region(asr_base, asr_length);
393 }
394
395 module_init(ibmasr_init);
396 module_exit(ibmasr_exit);
397
398 module_param(nowayout, int, 0);
399 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
400
401 MODULE_DESCRIPTION("IBM Automatic Server Restart driver");
402 MODULE_AUTHOR("Andrey Panin");
403 MODULE_LICENSE("GPL");
404 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);