1 /*
2 * CMOS/NV-RAM driver for Linux
3 *
4 * Copyright (C) 1997 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
5 * idea by and with help from Richard Jelinek <rj@suse.de>
6 * Portions copyright (c) 2001,2002 Sun Microsystems (thockin@sun.com)
7 *
8 * This driver allows you to access the contents of the non-volatile memory in
9 * the mc146818rtc.h real-time clock. This chip is built into all PCs and into
10 * many Atari machines. In the former it's called "CMOS-RAM", in the latter
11 * "NVRAM" (NV stands for non-volatile).
12 *
13 * The data are supplied as a (seekable) character device, /dev/nvram. The
14 * size of this file is dependent on the controller. The usual size is 114,
15 * the number of freely available bytes in the memory (i.e., not used by the
16 * RTC itself).
17 *
18 * Checksums over the NVRAM contents are managed by this driver. In case of a
19 * bad checksum, reads and writes return -EIO. The checksum can be initialized
20 * to a sane state either by ioctl(NVRAM_INIT) (clear whole NVRAM) or
21 * ioctl(NVRAM_SETCKS) (doesn't change contents, just makes checksum valid
22 * again; use with care!)
23 *
24 * This file also provides some functions for other parts of the kernel that
25 * want to access the NVRAM: nvram_{read,write,check_checksum,set_checksum}.
26 * Obviously this can be used only if this driver is always configured into
27 * the kernel and is not a module. Since the functions are used by some Atari
28 * drivers, this is the case on the Atari.
29 *
30 *
31 * 1.1 Cesar Barros: SMP locking fixes
32 * added changelog
33 * 1.2 Erik Gilling: Cobalt Networks support
34 * Tim Hockin: general cleanup, Cobalt support
35 * 1.3 Wim Van Sebroeck: convert PRINT_PROC to seq_file
36 */
37
38 #define NVRAM_VERSION "1.3"
39
40 #include <linux/module.h>
41 #include <linux/nvram.h>
42
43 #define PC 1
44 #define ATARI 2
45
46 /* select machine configuration */
47 #if defined(CONFIG_ATARI)
48 # define MACH ATARI
49 #elif defined(__i386__) || defined(__x86_64__) || defined(__arm__) /* and ?? */
50 # define MACH PC
51 #else
52 # error Cannot build nvram driver for this machine configuration.
53 #endif
54
55 #if MACH == PC
56
57 /* RTC in a PC */
58 #define CHECK_DRIVER_INIT() 1
59
60 /* On PCs, the checksum is built only over bytes 2..31 */
61 #define PC_CKS_RANGE_START 2
62 #define PC_CKS_RANGE_END 31
63 #define PC_CKS_LOC 32
64 #define NVRAM_BYTES (128-NVRAM_FIRST_BYTE)
65
66 #define mach_check_checksum pc_check_checksum
67 #define mach_set_checksum pc_set_checksum
68 #define mach_proc_infos pc_proc_infos
69
70 #endif
71
72 #if MACH == ATARI
73
74 /* Special parameters for RTC in Atari machines */
75 #include <asm/atarihw.h>
76 #include <asm/atariints.h>
77 #define RTC_PORT(x) (TT_RTC_BAS + 2*(x))
78 #define CHECK_DRIVER_INIT() (MACH_IS_ATARI && ATARIHW_PRESENT(TT_CLK))
79
80 #define NVRAM_BYTES 50
81
82 /* On Ataris, the checksum is over all bytes except the checksum bytes
83 * themselves; these are at the very end */
84 #define ATARI_CKS_RANGE_START 0
85 #define ATARI_CKS_RANGE_END 47
86 #define ATARI_CKS_LOC 48
87
88 #define mach_check_checksum atari_check_checksum
89 #define mach_set_checksum atari_set_checksum
90 #define mach_proc_infos atari_proc_infos
91
92 #endif
93
94 /* Note that *all* calls to CMOS_READ and CMOS_WRITE must be done with
95 * rtc_lock held. Due to the index-port/data-port design of the RTC, we
96 * don't want two different things trying to get to it at once. (e.g. the
97 * periodic 11 min sync from kernel/time/ntp.c vs. this driver.)
98 */
99
100 #include <linux/types.h>
101 #include <linux/errno.h>
102 #include <linux/miscdevice.h>
103 #include <linux/ioport.h>
104 #include <linux/fcntl.h>
105 #include <linux/mc146818rtc.h>
106 #include <linux/init.h>
107 #include <linux/proc_fs.h>
108 #include <linux/seq_file.h>
109 #include <linux/spinlock.h>
110 #include <linux/io.h>
111 #include <linux/uaccess.h>
112 #include <linux/mutex.h>
113 #include <linux/pagemap.h>
114
115
116 static DEFINE_MUTEX(nvram_mutex);
117 static DEFINE_SPINLOCK(nvram_state_lock);
118 static int nvram_open_cnt; /* #times opened */
119 static int nvram_open_mode; /* special open modes */
120 #define NVRAM_WRITE 1 /* opened for writing (exclusive) */
121 #define NVRAM_EXCL 2 /* opened with O_EXCL */
122
123 static int mach_check_checksum(void);
124 static void mach_set_checksum(void);
125
126 #ifdef CONFIG_PROC_FS
127 static void mach_proc_infos(unsigned char *contents, struct seq_file *seq,
128 void *offset);
129 #endif
130
131 /*
132 * These functions are provided to be called internally or by other parts of
133 * the kernel. It's up to the caller to ensure correct checksum before reading
134 * or after writing (needs to be done only once).
135 *
136 * It is worth noting that these functions all access bytes of general
137 * purpose memory in the NVRAM - that is to say, they all add the
138 * NVRAM_FIRST_BYTE offset. Pass them offsets into NVRAM as if you did not
139 * know about the RTC cruft.
140 */
141
__nvram_read_byte(int i)142 unsigned char __nvram_read_byte(int i)
143 {
144 return CMOS_READ(NVRAM_FIRST_BYTE + i);
145 }
146 EXPORT_SYMBOL(__nvram_read_byte);
147
nvram_read_byte(int i)148 unsigned char nvram_read_byte(int i)
149 {
150 unsigned long flags;
151 unsigned char c;
152
153 spin_lock_irqsave(&rtc_lock, flags);
154 c = __nvram_read_byte(i);
155 spin_unlock_irqrestore(&rtc_lock, flags);
156 return c;
157 }
158 EXPORT_SYMBOL(nvram_read_byte);
159
160 /* This races nicely with trying to read with checksum checking (nvram_read) */
__nvram_write_byte(unsigned char c,int i)161 void __nvram_write_byte(unsigned char c, int i)
162 {
163 CMOS_WRITE(c, NVRAM_FIRST_BYTE + i);
164 }
165 EXPORT_SYMBOL(__nvram_write_byte);
166
nvram_write_byte(unsigned char c,int i)167 void nvram_write_byte(unsigned char c, int i)
168 {
169 unsigned long flags;
170
171 spin_lock_irqsave(&rtc_lock, flags);
172 __nvram_write_byte(c, i);
173 spin_unlock_irqrestore(&rtc_lock, flags);
174 }
175 EXPORT_SYMBOL(nvram_write_byte);
176
__nvram_check_checksum(void)177 int __nvram_check_checksum(void)
178 {
179 return mach_check_checksum();
180 }
181 EXPORT_SYMBOL(__nvram_check_checksum);
182
nvram_check_checksum(void)183 int nvram_check_checksum(void)
184 {
185 unsigned long flags;
186 int rv;
187
188 spin_lock_irqsave(&rtc_lock, flags);
189 rv = __nvram_check_checksum();
190 spin_unlock_irqrestore(&rtc_lock, flags);
191 return rv;
192 }
193 EXPORT_SYMBOL(nvram_check_checksum);
194
__nvram_set_checksum(void)195 static void __nvram_set_checksum(void)
196 {
197 mach_set_checksum();
198 }
199
200 #if 0
201 void nvram_set_checksum(void)
202 {
203 unsigned long flags;
204
205 spin_lock_irqsave(&rtc_lock, flags);
206 __nvram_set_checksum();
207 spin_unlock_irqrestore(&rtc_lock, flags);
208 }
209 #endif /* 0 */
210
211 /*
212 * The are the file operation function for user access to /dev/nvram
213 */
214
nvram_llseek(struct file * file,loff_t offset,int origin)215 static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)
216 {
217 return generic_file_llseek_size(file, offset, origin, MAX_LFS_FILESIZE,
218 NVRAM_BYTES);
219 }
220
nvram_read(struct file * file,char __user * buf,size_t count,loff_t * ppos)221 static ssize_t nvram_read(struct file *file, char __user *buf,
222 size_t count, loff_t *ppos)
223 {
224 unsigned char contents[NVRAM_BYTES];
225 unsigned i = *ppos;
226 unsigned char *tmp;
227
228 spin_lock_irq(&rtc_lock);
229
230 if (!__nvram_check_checksum())
231 goto checksum_err;
232
233 for (tmp = contents; count-- > 0 && i < NVRAM_BYTES; ++i, ++tmp)
234 *tmp = __nvram_read_byte(i);
235
236 spin_unlock_irq(&rtc_lock);
237
238 if (copy_to_user(buf, contents, tmp - contents))
239 return -EFAULT;
240
241 *ppos = i;
242
243 return tmp - contents;
244
245 checksum_err:
246 spin_unlock_irq(&rtc_lock);
247 return -EIO;
248 }
249
nvram_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)250 static ssize_t nvram_write(struct file *file, const char __user *buf,
251 size_t count, loff_t *ppos)
252 {
253 unsigned char contents[NVRAM_BYTES];
254 unsigned i = *ppos;
255 unsigned char *tmp;
256
257 if (i >= NVRAM_BYTES)
258 return 0; /* Past EOF */
259
260 if (count > NVRAM_BYTES - i)
261 count = NVRAM_BYTES - i;
262 if (count > NVRAM_BYTES)
263 return -EFAULT; /* Can't happen, but prove it to gcc */
264
265 if (copy_from_user(contents, buf, count))
266 return -EFAULT;
267
268 spin_lock_irq(&rtc_lock);
269
270 if (!__nvram_check_checksum())
271 goto checksum_err;
272
273 for (tmp = contents; count--; ++i, ++tmp)
274 __nvram_write_byte(*tmp, i);
275
276 __nvram_set_checksum();
277
278 spin_unlock_irq(&rtc_lock);
279
280 *ppos = i;
281
282 return tmp - contents;
283
284 checksum_err:
285 spin_unlock_irq(&rtc_lock);
286 return -EIO;
287 }
288
nvram_ioctl(struct file * file,unsigned int cmd,unsigned long arg)289 static long nvram_ioctl(struct file *file, unsigned int cmd,
290 unsigned long arg)
291 {
292 int i;
293
294 switch (cmd) {
295
296 case NVRAM_INIT:
297 /* initialize NVRAM contents and checksum */
298 if (!capable(CAP_SYS_ADMIN))
299 return -EACCES;
300
301 mutex_lock(&nvram_mutex);
302 spin_lock_irq(&rtc_lock);
303
304 for (i = 0; i < NVRAM_BYTES; ++i)
305 __nvram_write_byte(0, i);
306 __nvram_set_checksum();
307
308 spin_unlock_irq(&rtc_lock);
309 mutex_unlock(&nvram_mutex);
310 return 0;
311
312 case NVRAM_SETCKS:
313 /* just set checksum, contents unchanged (maybe useful after
314 * checksum garbaged somehow...) */
315 if (!capable(CAP_SYS_ADMIN))
316 return -EACCES;
317
318 mutex_lock(&nvram_mutex);
319 spin_lock_irq(&rtc_lock);
320 __nvram_set_checksum();
321 spin_unlock_irq(&rtc_lock);
322 mutex_unlock(&nvram_mutex);
323 return 0;
324
325 default:
326 return -ENOTTY;
327 }
328 }
329
nvram_open(struct inode * inode,struct file * file)330 static int nvram_open(struct inode *inode, struct file *file)
331 {
332 spin_lock(&nvram_state_lock);
333
334 if ((nvram_open_cnt && (file->f_flags & O_EXCL)) ||
335 (nvram_open_mode & NVRAM_EXCL) ||
336 ((file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE))) {
337 spin_unlock(&nvram_state_lock);
338 return -EBUSY;
339 }
340
341 if (file->f_flags & O_EXCL)
342 nvram_open_mode |= NVRAM_EXCL;
343 if (file->f_mode & FMODE_WRITE)
344 nvram_open_mode |= NVRAM_WRITE;
345 nvram_open_cnt++;
346
347 spin_unlock(&nvram_state_lock);
348
349 return 0;
350 }
351
nvram_release(struct inode * inode,struct file * file)352 static int nvram_release(struct inode *inode, struct file *file)
353 {
354 spin_lock(&nvram_state_lock);
355
356 nvram_open_cnt--;
357
358 /* if only one instance is open, clear the EXCL bit */
359 if (nvram_open_mode & NVRAM_EXCL)
360 nvram_open_mode &= ~NVRAM_EXCL;
361 if (file->f_mode & FMODE_WRITE)
362 nvram_open_mode &= ~NVRAM_WRITE;
363
364 spin_unlock(&nvram_state_lock);
365
366 return 0;
367 }
368
369 #ifndef CONFIG_PROC_FS
nvram_add_proc_fs(void)370 static int nvram_add_proc_fs(void)
371 {
372 return 0;
373 }
374
375 #else
376
nvram_proc_read(struct seq_file * seq,void * offset)377 static int nvram_proc_read(struct seq_file *seq, void *offset)
378 {
379 unsigned char contents[NVRAM_BYTES];
380 int i = 0;
381
382 spin_lock_irq(&rtc_lock);
383 for (i = 0; i < NVRAM_BYTES; ++i)
384 contents[i] = __nvram_read_byte(i);
385 spin_unlock_irq(&rtc_lock);
386
387 mach_proc_infos(contents, seq, offset);
388
389 return 0;
390 }
391
nvram_add_proc_fs(void)392 static int nvram_add_proc_fs(void)
393 {
394 if (!proc_create_single("driver/nvram", 0, NULL, nvram_proc_read))
395 return -ENOMEM;
396 return 0;
397 }
398
399 #endif /* CONFIG_PROC_FS */
400
401 static const struct file_operations nvram_fops = {
402 .owner = THIS_MODULE,
403 .llseek = nvram_llseek,
404 .read = nvram_read,
405 .write = nvram_write,
406 .unlocked_ioctl = nvram_ioctl,
407 .open = nvram_open,
408 .release = nvram_release,
409 };
410
411 static struct miscdevice nvram_dev = {
412 NVRAM_MINOR,
413 "nvram",
414 &nvram_fops
415 };
416
nvram_init(void)417 static int __init nvram_init(void)
418 {
419 int ret;
420
421 /* First test whether the driver should init at all */
422 if (!CHECK_DRIVER_INIT())
423 return -ENODEV;
424
425 ret = misc_register(&nvram_dev);
426 if (ret) {
427 printk(KERN_ERR "nvram: can't misc_register on minor=%d\n",
428 NVRAM_MINOR);
429 goto out;
430 }
431 ret = nvram_add_proc_fs();
432 if (ret) {
433 printk(KERN_ERR "nvram: can't create /proc/driver/nvram\n");
434 goto outmisc;
435 }
436 ret = 0;
437 printk(KERN_INFO "Non-volatile memory driver v" NVRAM_VERSION "\n");
438 out:
439 return ret;
440 outmisc:
441 misc_deregister(&nvram_dev);
442 goto out;
443 }
444
nvram_cleanup_module(void)445 static void __exit nvram_cleanup_module(void)
446 {
447 remove_proc_entry("driver/nvram", NULL);
448 misc_deregister(&nvram_dev);
449 }
450
451 module_init(nvram_init);
452 module_exit(nvram_cleanup_module);
453
454 /*
455 * Machine specific functions
456 */
457
458 #if MACH == PC
459
pc_check_checksum(void)460 static int pc_check_checksum(void)
461 {
462 int i;
463 unsigned short sum = 0;
464 unsigned short expect;
465
466 for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
467 sum += __nvram_read_byte(i);
468 expect = __nvram_read_byte(PC_CKS_LOC)<<8 |
469 __nvram_read_byte(PC_CKS_LOC+1);
470 return (sum & 0xffff) == expect;
471 }
472
pc_set_checksum(void)473 static void pc_set_checksum(void)
474 {
475 int i;
476 unsigned short sum = 0;
477
478 for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
479 sum += __nvram_read_byte(i);
480 __nvram_write_byte(sum >> 8, PC_CKS_LOC);
481 __nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1);
482 }
483
484 #ifdef CONFIG_PROC_FS
485
486 static const char * const floppy_types[] = {
487 "none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M",
488 "3.5'' 2.88M", "3.5'' 2.88M"
489 };
490
491 static const char * const gfx_types[] = {
492 "EGA, VGA, ... (with BIOS)",
493 "CGA (40 cols)",
494 "CGA (80 cols)",
495 "monochrome",
496 };
497
pc_proc_infos(unsigned char * nvram,struct seq_file * seq,void * offset)498 static void pc_proc_infos(unsigned char *nvram, struct seq_file *seq,
499 void *offset)
500 {
501 int checksum;
502 int type;
503
504 spin_lock_irq(&rtc_lock);
505 checksum = __nvram_check_checksum();
506 spin_unlock_irq(&rtc_lock);
507
508 seq_printf(seq, "Checksum status: %svalid\n", checksum ? "" : "not ");
509
510 seq_printf(seq, "# floppies : %d\n",
511 (nvram[6] & 1) ? (nvram[6] >> 6) + 1 : 0);
512 seq_printf(seq, "Floppy 0 type : ");
513 type = nvram[2] >> 4;
514 if (type < ARRAY_SIZE(floppy_types))
515 seq_printf(seq, "%s\n", floppy_types[type]);
516 else
517 seq_printf(seq, "%d (unknown)\n", type);
518 seq_printf(seq, "Floppy 1 type : ");
519 type = nvram[2] & 0x0f;
520 if (type < ARRAY_SIZE(floppy_types))
521 seq_printf(seq, "%s\n", floppy_types[type]);
522 else
523 seq_printf(seq, "%d (unknown)\n", type);
524
525 seq_printf(seq, "HD 0 type : ");
526 type = nvram[4] >> 4;
527 if (type)
528 seq_printf(seq, "%02x\n", type == 0x0f ? nvram[11] : type);
529 else
530 seq_printf(seq, "none\n");
531
532 seq_printf(seq, "HD 1 type : ");
533 type = nvram[4] & 0x0f;
534 if (type)
535 seq_printf(seq, "%02x\n", type == 0x0f ? nvram[12] : type);
536 else
537 seq_printf(seq, "none\n");
538
539 seq_printf(seq, "HD type 48 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
540 nvram[18] | (nvram[19] << 8),
541 nvram[20], nvram[25],
542 nvram[21] | (nvram[22] << 8), nvram[23] | (nvram[24] << 8));
543 seq_printf(seq, "HD type 49 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
544 nvram[39] | (nvram[40] << 8),
545 nvram[41], nvram[46],
546 nvram[42] | (nvram[43] << 8), nvram[44] | (nvram[45] << 8));
547
548 seq_printf(seq, "DOS base memory: %d kB\n", nvram[7] | (nvram[8] << 8));
549 seq_printf(seq, "Extended memory: %d kB (configured), %d kB (tested)\n",
550 nvram[9] | (nvram[10] << 8), nvram[34] | (nvram[35] << 8));
551
552 seq_printf(seq, "Gfx adapter : %s\n",
553 gfx_types[(nvram[6] >> 4) & 3]);
554
555 seq_printf(seq, "FPU : %sinstalled\n",
556 (nvram[6] & 2) ? "" : "not ");
557
558 return;
559 }
560 #endif
561
562 #endif /* MACH == PC */
563
564 #if MACH == ATARI
565
atari_check_checksum(void)566 static int atari_check_checksum(void)
567 {
568 int i;
569 unsigned char sum = 0;
570
571 for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
572 sum += __nvram_read_byte(i);
573 return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) &&
574 (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
575 }
576
atari_set_checksum(void)577 static void atari_set_checksum(void)
578 {
579 int i;
580 unsigned char sum = 0;
581
582 for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
583 sum += __nvram_read_byte(i);
584 __nvram_write_byte(~sum, ATARI_CKS_LOC);
585 __nvram_write_byte(sum, ATARI_CKS_LOC + 1);
586 }
587
588 #ifdef CONFIG_PROC_FS
589
590 static struct {
591 unsigned char val;
592 const char *name;
593 } boot_prefs[] = {
594 { 0x80, "TOS" },
595 { 0x40, "ASV" },
596 { 0x20, "NetBSD (?)" },
597 { 0x10, "Linux" },
598 { 0x00, "unspecified" }
599 };
600
601 static const char * const languages[] = {
602 "English (US)",
603 "German",
604 "French",
605 "English (UK)",
606 "Spanish",
607 "Italian",
608 "6 (undefined)",
609 "Swiss (French)",
610 "Swiss (German)"
611 };
612
613 static const char * const dateformat[] = {
614 "MM%cDD%cYY",
615 "DD%cMM%cYY",
616 "YY%cMM%cDD",
617 "YY%cDD%cMM",
618 "4 (undefined)",
619 "5 (undefined)",
620 "6 (undefined)",
621 "7 (undefined)"
622 };
623
624 static const char * const colors[] = {
625 "2", "4", "16", "256", "65536", "??", "??", "??"
626 };
627
atari_proc_infos(unsigned char * nvram,struct seq_file * seq,void * offset)628 static void atari_proc_infos(unsigned char *nvram, struct seq_file *seq,
629 void *offset)
630 {
631 int checksum = nvram_check_checksum();
632 int i;
633 unsigned vmode;
634
635 seq_printf(seq, "Checksum status : %svalid\n", checksum ? "" : "not ");
636
637 seq_printf(seq, "Boot preference : ");
638 for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i) {
639 if (nvram[1] == boot_prefs[i].val) {
640 seq_printf(seq, "%s\n", boot_prefs[i].name);
641 break;
642 }
643 }
644 if (i < 0)
645 seq_printf(seq, "0x%02x (undefined)\n", nvram[1]);
646
647 seq_printf(seq, "SCSI arbitration : %s\n",
648 (nvram[16] & 0x80) ? "on" : "off");
649 seq_printf(seq, "SCSI host ID : ");
650 if (nvram[16] & 0x80)
651 seq_printf(seq, "%d\n", nvram[16] & 7);
652 else
653 seq_printf(seq, "n/a\n");
654
655 /* the following entries are defined only for the Falcon */
656 if ((atari_mch_cookie >> 16) != ATARI_MCH_FALCON)
657 return;
658
659 seq_printf(seq, "OS language : ");
660 if (nvram[6] < ARRAY_SIZE(languages))
661 seq_printf(seq, "%s\n", languages[nvram[6]]);
662 else
663 seq_printf(seq, "%u (undefined)\n", nvram[6]);
664 seq_printf(seq, "Keyboard language: ");
665 if (nvram[7] < ARRAY_SIZE(languages))
666 seq_printf(seq, "%s\n", languages[nvram[7]]);
667 else
668 seq_printf(seq, "%u (undefined)\n", nvram[7]);
669 seq_printf(seq, "Date format : ");
670 seq_printf(seq, dateformat[nvram[8] & 7],
671 nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/');
672 seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12);
673 seq_printf(seq, "Boot delay : ");
674 if (nvram[10] == 0)
675 seq_printf(seq, "default");
676 else
677 seq_printf(seq, "%ds%s\n", nvram[10],
678 nvram[10] < 8 ? ", no memory test" : "");
679
680 vmode = (nvram[14] << 8) | nvram[15];
681 seq_printf(seq,
682 "Video mode : %s colors, %d columns, %s %s monitor\n",
683 colors[vmode & 7],
684 vmode & 8 ? 80 : 40,
685 vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC");
686 seq_printf(seq, " %soverscan, compat. mode %s%s\n",
687 vmode & 64 ? "" : "no ",
688 vmode & 128 ? "on" : "off",
689 vmode & 256 ?
690 (vmode & 16 ? ", line doubling" : ", half screen") : "");
691
692 return;
693 }
694 #endif
695
696 #endif /* MACH == ATARI */
697
698 MODULE_LICENSE("GPL");
699 MODULE_ALIAS_MISCDEV(NVRAM_MINOR);
700