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 time.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> 113 114 #include <asm/system.h> 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 */ 141 142 unsigned char __nvram_read_byte(int i) 143 { 144 return CMOS_READ(NVRAM_FIRST_BYTE + i); 145 } 146 EXPORT_SYMBOL(__nvram_read_byte); 147 148 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) */ 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); 166 167 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); 176 177 int __nvram_check_checksum(void) 178 { 179 return mach_check_checksum(); 180 } 181 EXPORT_SYMBOL(__nvram_check_checksum); 182 183 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); 194 195 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 */ 214 215 static loff_t nvram_llseek(struct file *file, loff_t offset, int origin) 216 { 217 switch (origin) { 218 case 0: 219 /* nothing to do */ 220 break; 221 case 1: 222 offset += file->f_pos; 223 break; 224 case 2: 225 offset += NVRAM_BYTES; 226 break; 227 } 228 229 return (offset >= 0) ? (file->f_pos = offset) : -EINVAL; 230 } 231 232 static ssize_t nvram_read(struct file *file, char __user *buf, 233 size_t count, loff_t *ppos) 234 { 235 unsigned char contents[NVRAM_BYTES]; 236 unsigned i = *ppos; 237 unsigned char *tmp; 238 239 spin_lock_irq(&rtc_lock); 240 241 if (!__nvram_check_checksum()) 242 goto checksum_err; 243 244 for (tmp = contents; count-- > 0 && i < NVRAM_BYTES; ++i, ++tmp) 245 *tmp = __nvram_read_byte(i); 246 247 spin_unlock_irq(&rtc_lock); 248 249 if (copy_to_user(buf, contents, tmp - contents)) 250 return -EFAULT; 251 252 *ppos = i; 253 254 return tmp - contents; 255 256 checksum_err: 257 spin_unlock_irq(&rtc_lock); 258 return -EIO; 259 } 260 261 static ssize_t nvram_write(struct file *file, const char __user *buf, 262 size_t count, loff_t *ppos) 263 { 264 unsigned char contents[NVRAM_BYTES]; 265 unsigned i = *ppos; 266 unsigned char *tmp; 267 268 if (i >= NVRAM_BYTES) 269 return 0; /* Past EOF */ 270 271 if (count > NVRAM_BYTES - i) 272 count = NVRAM_BYTES - i; 273 if (count > NVRAM_BYTES) 274 return -EFAULT; /* Can't happen, but prove it to gcc */ 275 276 if (copy_from_user(contents, buf, count)) 277 return -EFAULT; 278 279 spin_lock_irq(&rtc_lock); 280 281 if (!__nvram_check_checksum()) 282 goto checksum_err; 283 284 for (tmp = contents; count--; ++i, ++tmp) 285 __nvram_write_byte(*tmp, i); 286 287 __nvram_set_checksum(); 288 289 spin_unlock_irq(&rtc_lock); 290 291 *ppos = i; 292 293 return tmp - contents; 294 295 checksum_err: 296 spin_unlock_irq(&rtc_lock); 297 return -EIO; 298 } 299 300 static long nvram_ioctl(struct file *file, unsigned int cmd, 301 unsigned long arg) 302 { 303 int i; 304 305 switch (cmd) { 306 307 case NVRAM_INIT: 308 /* initialize NVRAM contents and checksum */ 309 if (!capable(CAP_SYS_ADMIN)) 310 return -EACCES; 311 312 mutex_lock(&nvram_mutex); 313 spin_lock_irq(&rtc_lock); 314 315 for (i = 0; i < NVRAM_BYTES; ++i) 316 __nvram_write_byte(0, i); 317 __nvram_set_checksum(); 318 319 spin_unlock_irq(&rtc_lock); 320 mutex_unlock(&nvram_mutex); 321 return 0; 322 323 case NVRAM_SETCKS: 324 /* just set checksum, contents unchanged (maybe useful after 325 * checksum garbaged somehow...) */ 326 if (!capable(CAP_SYS_ADMIN)) 327 return -EACCES; 328 329 mutex_lock(&nvram_mutex); 330 spin_lock_irq(&rtc_lock); 331 __nvram_set_checksum(); 332 spin_unlock_irq(&rtc_lock); 333 mutex_unlock(&nvram_mutex); 334 return 0; 335 336 default: 337 return -ENOTTY; 338 } 339 } 340 341 static int nvram_open(struct inode *inode, struct file *file) 342 { 343 spin_lock(&nvram_state_lock); 344 345 if ((nvram_open_cnt && (file->f_flags & O_EXCL)) || 346 (nvram_open_mode & NVRAM_EXCL) || 347 ((file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE))) { 348 spin_unlock(&nvram_state_lock); 349 return -EBUSY; 350 } 351 352 if (file->f_flags & O_EXCL) 353 nvram_open_mode |= NVRAM_EXCL; 354 if (file->f_mode & FMODE_WRITE) 355 nvram_open_mode |= NVRAM_WRITE; 356 nvram_open_cnt++; 357 358 spin_unlock(&nvram_state_lock); 359 360 return 0; 361 } 362 363 static int nvram_release(struct inode *inode, struct file *file) 364 { 365 spin_lock(&nvram_state_lock); 366 367 nvram_open_cnt--; 368 369 /* if only one instance is open, clear the EXCL bit */ 370 if (nvram_open_mode & NVRAM_EXCL) 371 nvram_open_mode &= ~NVRAM_EXCL; 372 if (file->f_mode & FMODE_WRITE) 373 nvram_open_mode &= ~NVRAM_WRITE; 374 375 spin_unlock(&nvram_state_lock); 376 377 return 0; 378 } 379 380 #ifndef CONFIG_PROC_FS 381 static int nvram_add_proc_fs(void) 382 { 383 return 0; 384 } 385 386 #else 387 388 static int nvram_proc_read(struct seq_file *seq, void *offset) 389 { 390 unsigned char contents[NVRAM_BYTES]; 391 int i = 0; 392 393 spin_lock_irq(&rtc_lock); 394 for (i = 0; i < NVRAM_BYTES; ++i) 395 contents[i] = __nvram_read_byte(i); 396 spin_unlock_irq(&rtc_lock); 397 398 mach_proc_infos(contents, seq, offset); 399 400 return 0; 401 } 402 403 static int nvram_proc_open(struct inode *inode, struct file *file) 404 { 405 return single_open(file, nvram_proc_read, NULL); 406 } 407 408 static const struct file_operations nvram_proc_fops = { 409 .owner = THIS_MODULE, 410 .open = nvram_proc_open, 411 .read = seq_read, 412 .llseek = seq_lseek, 413 .release = single_release, 414 }; 415 416 static int nvram_add_proc_fs(void) 417 { 418 if (!proc_create("driver/nvram", 0, NULL, &nvram_proc_fops)) 419 return -ENOMEM; 420 return 0; 421 } 422 423 #endif /* CONFIG_PROC_FS */ 424 425 static const struct file_operations nvram_fops = { 426 .owner = THIS_MODULE, 427 .llseek = nvram_llseek, 428 .read = nvram_read, 429 .write = nvram_write, 430 .unlocked_ioctl = nvram_ioctl, 431 .open = nvram_open, 432 .release = nvram_release, 433 }; 434 435 static struct miscdevice nvram_dev = { 436 NVRAM_MINOR, 437 "nvram", 438 &nvram_fops 439 }; 440 441 static int __init nvram_init(void) 442 { 443 int ret; 444 445 /* First test whether the driver should init at all */ 446 if (!CHECK_DRIVER_INIT()) 447 return -ENODEV; 448 449 ret = misc_register(&nvram_dev); 450 if (ret) { 451 printk(KERN_ERR "nvram: can't misc_register on minor=%d\n", 452 NVRAM_MINOR); 453 goto out; 454 } 455 ret = nvram_add_proc_fs(); 456 if (ret) { 457 printk(KERN_ERR "nvram: can't create /proc/driver/nvram\n"); 458 goto outmisc; 459 } 460 ret = 0; 461 printk(KERN_INFO "Non-volatile memory driver v" NVRAM_VERSION "\n"); 462 out: 463 return ret; 464 outmisc: 465 misc_deregister(&nvram_dev); 466 goto out; 467 } 468 469 static void __exit nvram_cleanup_module(void) 470 { 471 remove_proc_entry("driver/nvram", NULL); 472 misc_deregister(&nvram_dev); 473 } 474 475 module_init(nvram_init); 476 module_exit(nvram_cleanup_module); 477 478 /* 479 * Machine specific functions 480 */ 481 482 #if MACH == PC 483 484 static int pc_check_checksum(void) 485 { 486 int i; 487 unsigned short sum = 0; 488 unsigned short expect; 489 490 for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i) 491 sum += __nvram_read_byte(i); 492 expect = __nvram_read_byte(PC_CKS_LOC)<<8 | 493 __nvram_read_byte(PC_CKS_LOC+1); 494 return (sum & 0xffff) == expect; 495 } 496 497 static void pc_set_checksum(void) 498 { 499 int i; 500 unsigned short sum = 0; 501 502 for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i) 503 sum += __nvram_read_byte(i); 504 __nvram_write_byte(sum >> 8, PC_CKS_LOC); 505 __nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1); 506 } 507 508 #ifdef CONFIG_PROC_FS 509 510 static char *floppy_types[] = { 511 "none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M", 512 "3.5'' 2.88M", "3.5'' 2.88M" 513 }; 514 515 static char *gfx_types[] = { 516 "EGA, VGA, ... (with BIOS)", 517 "CGA (40 cols)", 518 "CGA (80 cols)", 519 "monochrome", 520 }; 521 522 static void pc_proc_infos(unsigned char *nvram, struct seq_file *seq, 523 void *offset) 524 { 525 int checksum; 526 int type; 527 528 spin_lock_irq(&rtc_lock); 529 checksum = __nvram_check_checksum(); 530 spin_unlock_irq(&rtc_lock); 531 532 seq_printf(seq, "Checksum status: %svalid\n", checksum ? "" : "not "); 533 534 seq_printf(seq, "# floppies : %d\n", 535 (nvram[6] & 1) ? (nvram[6] >> 6) + 1 : 0); 536 seq_printf(seq, "Floppy 0 type : "); 537 type = nvram[2] >> 4; 538 if (type < ARRAY_SIZE(floppy_types)) 539 seq_printf(seq, "%s\n", floppy_types[type]); 540 else 541 seq_printf(seq, "%d (unknown)\n", type); 542 seq_printf(seq, "Floppy 1 type : "); 543 type = nvram[2] & 0x0f; 544 if (type < ARRAY_SIZE(floppy_types)) 545 seq_printf(seq, "%s\n", floppy_types[type]); 546 else 547 seq_printf(seq, "%d (unknown)\n", type); 548 549 seq_printf(seq, "HD 0 type : "); 550 type = nvram[4] >> 4; 551 if (type) 552 seq_printf(seq, "%02x\n", type == 0x0f ? nvram[11] : type); 553 else 554 seq_printf(seq, "none\n"); 555 556 seq_printf(seq, "HD 1 type : "); 557 type = nvram[4] & 0x0f; 558 if (type) 559 seq_printf(seq, "%02x\n", type == 0x0f ? nvram[12] : type); 560 else 561 seq_printf(seq, "none\n"); 562 563 seq_printf(seq, "HD type 48 data: %d/%d/%d C/H/S, precomp %d, lz %d\n", 564 nvram[18] | (nvram[19] << 8), 565 nvram[20], nvram[25], 566 nvram[21] | (nvram[22] << 8), nvram[23] | (nvram[24] << 8)); 567 seq_printf(seq, "HD type 49 data: %d/%d/%d C/H/S, precomp %d, lz %d\n", 568 nvram[39] | (nvram[40] << 8), 569 nvram[41], nvram[46], 570 nvram[42] | (nvram[43] << 8), nvram[44] | (nvram[45] << 8)); 571 572 seq_printf(seq, "DOS base memory: %d kB\n", nvram[7] | (nvram[8] << 8)); 573 seq_printf(seq, "Extended memory: %d kB (configured), %d kB (tested)\n", 574 nvram[9] | (nvram[10] << 8), nvram[34] | (nvram[35] << 8)); 575 576 seq_printf(seq, "Gfx adapter : %s\n", 577 gfx_types[(nvram[6] >> 4) & 3]); 578 579 seq_printf(seq, "FPU : %sinstalled\n", 580 (nvram[6] & 2) ? "" : "not "); 581 582 return; 583 } 584 #endif 585 586 #endif /* MACH == PC */ 587 588 #if MACH == ATARI 589 590 static int atari_check_checksum(void) 591 { 592 int i; 593 unsigned char sum = 0; 594 595 for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i) 596 sum += __nvram_read_byte(i); 597 return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) && 598 (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff)); 599 } 600 601 static void atari_set_checksum(void) 602 { 603 int i; 604 unsigned char sum = 0; 605 606 for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i) 607 sum += __nvram_read_byte(i); 608 __nvram_write_byte(~sum, ATARI_CKS_LOC); 609 __nvram_write_byte(sum, ATARI_CKS_LOC + 1); 610 } 611 612 #ifdef CONFIG_PROC_FS 613 614 static struct { 615 unsigned char val; 616 char *name; 617 } boot_prefs[] = { 618 { 0x80, "TOS" }, 619 { 0x40, "ASV" }, 620 { 0x20, "NetBSD (?)" }, 621 { 0x10, "Linux" }, 622 { 0x00, "unspecified" } 623 }; 624 625 static char *languages[] = { 626 "English (US)", 627 "German", 628 "French", 629 "English (UK)", 630 "Spanish", 631 "Italian", 632 "6 (undefined)", 633 "Swiss (French)", 634 "Swiss (German)" 635 }; 636 637 static char *dateformat[] = { 638 "MM%cDD%cYY", 639 "DD%cMM%cYY", 640 "YY%cMM%cDD", 641 "YY%cDD%cMM", 642 "4 (undefined)", 643 "5 (undefined)", 644 "6 (undefined)", 645 "7 (undefined)" 646 }; 647 648 static char *colors[] = { 649 "2", "4", "16", "256", "65536", "??", "??", "??" 650 }; 651 652 static void atari_proc_infos(unsigned char *nvram, struct seq_file *seq, 653 void *offset) 654 { 655 int checksum = nvram_check_checksum(); 656 int i; 657 unsigned vmode; 658 659 seq_printf(seq, "Checksum status : %svalid\n", checksum ? "" : "not "); 660 661 seq_printf(seq, "Boot preference : "); 662 for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i) { 663 if (nvram[1] == boot_prefs[i].val) { 664 seq_printf(seq, "%s\n", boot_prefs[i].name); 665 break; 666 } 667 } 668 if (i < 0) 669 seq_printf(seq, "0x%02x (undefined)\n", nvram[1]); 670 671 seq_printf(seq, "SCSI arbitration : %s\n", 672 (nvram[16] & 0x80) ? "on" : "off"); 673 seq_printf(seq, "SCSI host ID : "); 674 if (nvram[16] & 0x80) 675 seq_printf(seq, "%d\n", nvram[16] & 7); 676 else 677 seq_printf(seq, "n/a\n"); 678 679 /* the following entries are defined only for the Falcon */ 680 if ((atari_mch_cookie >> 16) != ATARI_MCH_FALCON) 681 return; 682 683 seq_printf(seq, "OS language : "); 684 if (nvram[6] < ARRAY_SIZE(languages)) 685 seq_printf(seq, "%s\n", languages[nvram[6]]); 686 else 687 seq_printf(seq, "%u (undefined)\n", nvram[6]); 688 seq_printf(seq, "Keyboard language: "); 689 if (nvram[7] < ARRAY_SIZE(languages)) 690 seq_printf(seq, "%s\n", languages[nvram[7]]); 691 else 692 seq_printf(seq, "%u (undefined)\n", nvram[7]); 693 seq_printf(seq, "Date format : "); 694 seq_printf(seq, dateformat[nvram[8] & 7], 695 nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/'); 696 seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12); 697 seq_printf(seq, "Boot delay : "); 698 if (nvram[10] == 0) 699 seq_printf(seq, "default"); 700 else 701 seq_printf(seq, "%ds%s\n", nvram[10], 702 nvram[10] < 8 ? ", no memory test" : ""); 703 704 vmode = (nvram[14] << 8) || nvram[15]; 705 seq_printf(seq, 706 "Video mode : %s colors, %d columns, %s %s monitor\n", 707 colors[vmode & 7], 708 vmode & 8 ? 80 : 40, 709 vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC"); 710 seq_printf(seq, " %soverscan, compat. mode %s%s\n", 711 vmode & 64 ? "" : "no ", 712 vmode & 128 ? "on" : "off", 713 vmode & 256 ? 714 (vmode & 16 ? ", line doubling" : ", half screen") : ""); 715 716 return; 717 } 718 #endif 719 720 #endif /* MACH == ATARI */ 721 722 MODULE_LICENSE("GPL"); 723 MODULE_ALIAS_MISCDEV(NVRAM_MINOR); 724