linux/drivers/char/nvram.c
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   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
 114
 115static DEFINE_MUTEX(nvram_mutex);
 116static DEFINE_SPINLOCK(nvram_state_lock);
 117static int nvram_open_cnt;      /* #times opened */
 118static int nvram_open_mode;     /* special open modes */
 119#define NVRAM_WRITE             1 /* opened for writing (exclusive) */
 120#define NVRAM_EXCL              2 /* opened with O_EXCL */
 121
 122static int mach_check_checksum(void);
 123static void mach_set_checksum(void);
 124
 125#ifdef CONFIG_PROC_FS
 126static void mach_proc_infos(unsigned char *contents, struct seq_file *seq,
 127                                                                void *offset);
 128#endif
 129
 130/*
 131 * These functions are provided to be called internally or by other parts of
 132 * the kernel. It's up to the caller to ensure correct checksum before reading
 133 * or after writing (needs to be done only once).
 134 *
 135 * It is worth noting that these functions all access bytes of general
 136 * purpose memory in the NVRAM - that is to say, they all add the
 137 * NVRAM_FIRST_BYTE offset.  Pass them offsets into NVRAM as if you did not
 138 * know about the RTC cruft.
 139 */
 140
 141unsigned char __nvram_read_byte(int i)
 142{
 143        return CMOS_READ(NVRAM_FIRST_BYTE + i);
 144}
 145EXPORT_SYMBOL(__nvram_read_byte);
 146
 147unsigned char nvram_read_byte(int i)
 148{
 149        unsigned long flags;
 150        unsigned char c;
 151
 152        spin_lock_irqsave(&rtc_lock, flags);
 153        c = __nvram_read_byte(i);
 154        spin_unlock_irqrestore(&rtc_lock, flags);
 155        return c;
 156}
 157EXPORT_SYMBOL(nvram_read_byte);
 158
 159/* This races nicely with trying to read with checksum checking (nvram_read) */
 160void __nvram_write_byte(unsigned char c, int i)
 161{
 162        CMOS_WRITE(c, NVRAM_FIRST_BYTE + i);
 163}
 164EXPORT_SYMBOL(__nvram_write_byte);
 165
 166void nvram_write_byte(unsigned char c, int i)
 167{
 168        unsigned long flags;
 169
 170        spin_lock_irqsave(&rtc_lock, flags);
 171        __nvram_write_byte(c, i);
 172        spin_unlock_irqrestore(&rtc_lock, flags);
 173}
 174EXPORT_SYMBOL(nvram_write_byte);
 175
 176int __nvram_check_checksum(void)
 177{
 178        return mach_check_checksum();
 179}
 180EXPORT_SYMBOL(__nvram_check_checksum);
 181
 182int nvram_check_checksum(void)
 183{
 184        unsigned long flags;
 185        int rv;
 186
 187        spin_lock_irqsave(&rtc_lock, flags);
 188        rv = __nvram_check_checksum();
 189        spin_unlock_irqrestore(&rtc_lock, flags);
 190        return rv;
 191}
 192EXPORT_SYMBOL(nvram_check_checksum);
 193
 194static void __nvram_set_checksum(void)
 195{
 196        mach_set_checksum();
 197}
 198
 199#if 0
 200void nvram_set_checksum(void)
 201{
 202        unsigned long flags;
 203
 204        spin_lock_irqsave(&rtc_lock, flags);
 205        __nvram_set_checksum();
 206        spin_unlock_irqrestore(&rtc_lock, flags);
 207}
 208#endif  /*  0  */
 209
 210/*
 211 * The are the file operation function for user access to /dev/nvram
 212 */
 213
 214static loff_t nvram_llseek(struct file *file, loff_t offset, int origin)
 215{
 216        switch (origin) {
 217        case 0:
 218                /* nothing to do */
 219                break;
 220        case 1:
 221                offset += file->f_pos;
 222                break;
 223        case 2:
 224                offset += NVRAM_BYTES;
 225                break;
 226        default:
 227                return -EINVAL;
 228        }
 229
 230        return (offset >= 0) ? (file->f_pos = offset) : -EINVAL;
 231}
 232
 233static ssize_t nvram_read(struct file *file, char __user *buf,
 234                                                size_t count, loff_t *ppos)
 235{
 236        unsigned char contents[NVRAM_BYTES];
 237        unsigned i = *ppos;
 238        unsigned char *tmp;
 239
 240        spin_lock_irq(&rtc_lock);
 241
 242        if (!__nvram_check_checksum())
 243                goto checksum_err;
 244
 245        for (tmp = contents; count-- > 0 && i < NVRAM_BYTES; ++i, ++tmp)
 246                *tmp = __nvram_read_byte(i);
 247
 248        spin_unlock_irq(&rtc_lock);
 249
 250        if (copy_to_user(buf, contents, tmp - contents))
 251                return -EFAULT;
 252
 253        *ppos = i;
 254
 255        return tmp - contents;
 256
 257checksum_err:
 258        spin_unlock_irq(&rtc_lock);
 259        return -EIO;
 260}
 261
 262static ssize_t nvram_write(struct file *file, const char __user *buf,
 263                                                size_t count, loff_t *ppos)
 264{
 265        unsigned char contents[NVRAM_BYTES];
 266        unsigned i = *ppos;
 267        unsigned char *tmp;
 268
 269        if (i >= NVRAM_BYTES)
 270                return 0;       /* Past EOF */
 271
 272        if (count > NVRAM_BYTES - i)
 273                count = NVRAM_BYTES - i;
 274        if (count > NVRAM_BYTES)
 275                return -EFAULT; /* Can't happen, but prove it to gcc */
 276
 277        if (copy_from_user(contents, buf, count))
 278                return -EFAULT;
 279
 280        spin_lock_irq(&rtc_lock);
 281
 282        if (!__nvram_check_checksum())
 283                goto checksum_err;
 284
 285        for (tmp = contents; count--; ++i, ++tmp)
 286                __nvram_write_byte(*tmp, i);
 287
 288        __nvram_set_checksum();
 289
 290        spin_unlock_irq(&rtc_lock);
 291
 292        *ppos = i;
 293
 294        return tmp - contents;
 295
 296checksum_err:
 297        spin_unlock_irq(&rtc_lock);
 298        return -EIO;
 299}
 300
 301static long nvram_ioctl(struct file *file, unsigned int cmd,
 302                        unsigned long arg)
 303{
 304        int i;
 305
 306        switch (cmd) {
 307
 308        case NVRAM_INIT:
 309                /* initialize NVRAM contents and checksum */
 310                if (!capable(CAP_SYS_ADMIN))
 311                        return -EACCES;
 312
 313                mutex_lock(&nvram_mutex);
 314                spin_lock_irq(&rtc_lock);
 315
 316                for (i = 0; i < NVRAM_BYTES; ++i)
 317                        __nvram_write_byte(0, i);
 318                __nvram_set_checksum();
 319
 320                spin_unlock_irq(&rtc_lock);
 321                mutex_unlock(&nvram_mutex);
 322                return 0;
 323
 324        case NVRAM_SETCKS:
 325                /* just set checksum, contents unchanged (maybe useful after
 326                 * checksum garbaged somehow...) */
 327                if (!capable(CAP_SYS_ADMIN))
 328                        return -EACCES;
 329
 330                mutex_lock(&nvram_mutex);
 331                spin_lock_irq(&rtc_lock);
 332                __nvram_set_checksum();
 333                spin_unlock_irq(&rtc_lock);
 334                mutex_unlock(&nvram_mutex);
 335                return 0;
 336
 337        default:
 338                return -ENOTTY;
 339        }
 340}
 341
 342static int nvram_open(struct inode *inode, struct file *file)
 343{
 344        spin_lock(&nvram_state_lock);
 345
 346        if ((nvram_open_cnt && (file->f_flags & O_EXCL)) ||
 347            (nvram_open_mode & NVRAM_EXCL) ||
 348            ((file->f_mode & FMODE_WRITE) && (nvram_open_mode & NVRAM_WRITE))) {
 349                spin_unlock(&nvram_state_lock);
 350                return -EBUSY;
 351        }
 352
 353        if (file->f_flags & O_EXCL)
 354                nvram_open_mode |= NVRAM_EXCL;
 355        if (file->f_mode & FMODE_WRITE)
 356                nvram_open_mode |= NVRAM_WRITE;
 357        nvram_open_cnt++;
 358
 359        spin_unlock(&nvram_state_lock);
 360
 361        return 0;
 362}
 363
 364static int nvram_release(struct inode *inode, struct file *file)
 365{
 366        spin_lock(&nvram_state_lock);
 367
 368        nvram_open_cnt--;
 369
 370        /* if only one instance is open, clear the EXCL bit */
 371        if (nvram_open_mode & NVRAM_EXCL)
 372                nvram_open_mode &= ~NVRAM_EXCL;
 373        if (file->f_mode & FMODE_WRITE)
 374                nvram_open_mode &= ~NVRAM_WRITE;
 375
 376        spin_unlock(&nvram_state_lock);
 377
 378        return 0;
 379}
 380
 381#ifndef CONFIG_PROC_FS
 382static int nvram_add_proc_fs(void)
 383{
 384        return 0;
 385}
 386
 387#else
 388
 389static int nvram_proc_read(struct seq_file *seq, void *offset)
 390{
 391        unsigned char contents[NVRAM_BYTES];
 392        int i = 0;
 393
 394        spin_lock_irq(&rtc_lock);
 395        for (i = 0; i < NVRAM_BYTES; ++i)
 396                contents[i] = __nvram_read_byte(i);
 397        spin_unlock_irq(&rtc_lock);
 398
 399        mach_proc_infos(contents, seq, offset);
 400
 401        return 0;
 402}
 403
 404static int nvram_proc_open(struct inode *inode, struct file *file)
 405{
 406        return single_open(file, nvram_proc_read, NULL);
 407}
 408
 409static const struct file_operations nvram_proc_fops = {
 410        .owner          = THIS_MODULE,
 411        .open           = nvram_proc_open,
 412        .read           = seq_read,
 413        .llseek         = seq_lseek,
 414        .release        = single_release,
 415};
 416
 417static int nvram_add_proc_fs(void)
 418{
 419        if (!proc_create("driver/nvram", 0, NULL, &nvram_proc_fops))
 420                return -ENOMEM;
 421        return 0;
 422}
 423
 424#endif /* CONFIG_PROC_FS */
 425
 426static const struct file_operations nvram_fops = {
 427        .owner          = THIS_MODULE,
 428        .llseek         = nvram_llseek,
 429        .read           = nvram_read,
 430        .write          = nvram_write,
 431        .unlocked_ioctl = nvram_ioctl,
 432        .open           = nvram_open,
 433        .release        = nvram_release,
 434};
 435
 436static struct miscdevice nvram_dev = {
 437        NVRAM_MINOR,
 438        "nvram",
 439        &nvram_fops
 440};
 441
 442static int __init nvram_init(void)
 443{
 444        int ret;
 445
 446        /* First test whether the driver should init at all */
 447        if (!CHECK_DRIVER_INIT())
 448                return -ENODEV;
 449
 450        ret = misc_register(&nvram_dev);
 451        if (ret) {
 452                printk(KERN_ERR "nvram: can't misc_register on minor=%d\n",
 453                    NVRAM_MINOR);
 454                goto out;
 455        }
 456        ret = nvram_add_proc_fs();
 457        if (ret) {
 458                printk(KERN_ERR "nvram: can't create /proc/driver/nvram\n");
 459                goto outmisc;
 460        }
 461        ret = 0;
 462        printk(KERN_INFO "Non-volatile memory driver v" NVRAM_VERSION "\n");
 463out:
 464        return ret;
 465outmisc:
 466        misc_deregister(&nvram_dev);
 467        goto out;
 468}
 469
 470static void __exit nvram_cleanup_module(void)
 471{
 472        remove_proc_entry("driver/nvram", NULL);
 473        misc_deregister(&nvram_dev);
 474}
 475
 476module_init(nvram_init);
 477module_exit(nvram_cleanup_module);
 478
 479/*
 480 * Machine specific functions
 481 */
 482
 483#if MACH == PC
 484
 485static int pc_check_checksum(void)
 486{
 487        int i;
 488        unsigned short sum = 0;
 489        unsigned short expect;
 490
 491        for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
 492                sum += __nvram_read_byte(i);
 493        expect = __nvram_read_byte(PC_CKS_LOC)<<8 |
 494            __nvram_read_byte(PC_CKS_LOC+1);
 495        return (sum & 0xffff) == expect;
 496}
 497
 498static void pc_set_checksum(void)
 499{
 500        int i;
 501        unsigned short sum = 0;
 502
 503        for (i = PC_CKS_RANGE_START; i <= PC_CKS_RANGE_END; ++i)
 504                sum += __nvram_read_byte(i);
 505        __nvram_write_byte(sum >> 8, PC_CKS_LOC);
 506        __nvram_write_byte(sum & 0xff, PC_CKS_LOC + 1);
 507}
 508
 509#ifdef CONFIG_PROC_FS
 510
 511static char *floppy_types[] = {
 512        "none", "5.25'' 360k", "5.25'' 1.2M", "3.5'' 720k", "3.5'' 1.44M",
 513        "3.5'' 2.88M", "3.5'' 2.88M"
 514};
 515
 516static char *gfx_types[] = {
 517        "EGA, VGA, ... (with BIOS)",
 518        "CGA (40 cols)",
 519        "CGA (80 cols)",
 520        "monochrome",
 521};
 522
 523static void pc_proc_infos(unsigned char *nvram, struct seq_file *seq,
 524                                                                void *offset)
 525{
 526        int checksum;
 527        int type;
 528
 529        spin_lock_irq(&rtc_lock);
 530        checksum = __nvram_check_checksum();
 531        spin_unlock_irq(&rtc_lock);
 532
 533        seq_printf(seq, "Checksum status: %svalid\n", checksum ? "" : "not ");
 534
 535        seq_printf(seq, "# floppies     : %d\n",
 536            (nvram[6] & 1) ? (nvram[6] >> 6) + 1 : 0);
 537        seq_printf(seq, "Floppy 0 type  : ");
 538        type = nvram[2] >> 4;
 539        if (type < ARRAY_SIZE(floppy_types))
 540                seq_printf(seq, "%s\n", floppy_types[type]);
 541        else
 542                seq_printf(seq, "%d (unknown)\n", type);
 543        seq_printf(seq, "Floppy 1 type  : ");
 544        type = nvram[2] & 0x0f;
 545        if (type < ARRAY_SIZE(floppy_types))
 546                seq_printf(seq, "%s\n", floppy_types[type]);
 547        else
 548                seq_printf(seq, "%d (unknown)\n", type);
 549
 550        seq_printf(seq, "HD 0 type      : ");
 551        type = nvram[4] >> 4;
 552        if (type)
 553                seq_printf(seq, "%02x\n", type == 0x0f ? nvram[11] : type);
 554        else
 555                seq_printf(seq, "none\n");
 556
 557        seq_printf(seq, "HD 1 type      : ");
 558        type = nvram[4] & 0x0f;
 559        if (type)
 560                seq_printf(seq, "%02x\n", type == 0x0f ? nvram[12] : type);
 561        else
 562                seq_printf(seq, "none\n");
 563
 564        seq_printf(seq, "HD type 48 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
 565            nvram[18] | (nvram[19] << 8),
 566            nvram[20], nvram[25],
 567            nvram[21] | (nvram[22] << 8), nvram[23] | (nvram[24] << 8));
 568        seq_printf(seq, "HD type 49 data: %d/%d/%d C/H/S, precomp %d, lz %d\n",
 569            nvram[39] | (nvram[40] << 8),
 570            nvram[41], nvram[46],
 571            nvram[42] | (nvram[43] << 8), nvram[44] | (nvram[45] << 8));
 572
 573        seq_printf(seq, "DOS base memory: %d kB\n", nvram[7] | (nvram[8] << 8));
 574        seq_printf(seq, "Extended memory: %d kB (configured), %d kB (tested)\n",
 575            nvram[9] | (nvram[10] << 8), nvram[34] | (nvram[35] << 8));
 576
 577        seq_printf(seq, "Gfx adapter    : %s\n",
 578            gfx_types[(nvram[6] >> 4) & 3]);
 579
 580        seq_printf(seq, "FPU            : %sinstalled\n",
 581            (nvram[6] & 2) ? "" : "not ");
 582
 583        return;
 584}
 585#endif
 586
 587#endif /* MACH == PC */
 588
 589#if MACH == ATARI
 590
 591static int atari_check_checksum(void)
 592{
 593        int i;
 594        unsigned char sum = 0;
 595
 596        for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
 597                sum += __nvram_read_byte(i);
 598        return (__nvram_read_byte(ATARI_CKS_LOC) == (~sum & 0xff)) &&
 599            (__nvram_read_byte(ATARI_CKS_LOC + 1) == (sum & 0xff));
 600}
 601
 602static void atari_set_checksum(void)
 603{
 604        int i;
 605        unsigned char sum = 0;
 606
 607        for (i = ATARI_CKS_RANGE_START; i <= ATARI_CKS_RANGE_END; ++i)
 608                sum += __nvram_read_byte(i);
 609        __nvram_write_byte(~sum, ATARI_CKS_LOC);
 610        __nvram_write_byte(sum, ATARI_CKS_LOC + 1);
 611}
 612
 613#ifdef CONFIG_PROC_FS
 614
 615static struct {
 616        unsigned char val;
 617        char *name;
 618} boot_prefs[] = {
 619        { 0x80, "TOS" },
 620        { 0x40, "ASV" },
 621        { 0x20, "NetBSD (?)" },
 622        { 0x10, "Linux" },
 623        { 0x00, "unspecified" }
 624};
 625
 626static char *languages[] = {
 627        "English (US)",
 628        "German",
 629        "French",
 630        "English (UK)",
 631        "Spanish",
 632        "Italian",
 633        "6 (undefined)",
 634        "Swiss (French)",
 635        "Swiss (German)"
 636};
 637
 638static char *dateformat[] = {
 639        "MM%cDD%cYY",
 640        "DD%cMM%cYY",
 641        "YY%cMM%cDD",
 642        "YY%cDD%cMM",
 643        "4 (undefined)",
 644        "5 (undefined)",
 645        "6 (undefined)",
 646        "7 (undefined)"
 647};
 648
 649static char *colors[] = {
 650        "2", "4", "16", "256", "65536", "??", "??", "??"
 651};
 652
 653static void atari_proc_infos(unsigned char *nvram, struct seq_file *seq,
 654                                                                void *offset)
 655{
 656        int checksum = nvram_check_checksum();
 657        int i;
 658        unsigned vmode;
 659
 660        seq_printf(seq, "Checksum status  : %svalid\n", checksum ? "" : "not ");
 661
 662        seq_printf(seq, "Boot preference  : ");
 663        for (i = ARRAY_SIZE(boot_prefs) - 1; i >= 0; --i) {
 664                if (nvram[1] == boot_prefs[i].val) {
 665                        seq_printf(seq, "%s\n", boot_prefs[i].name);
 666                        break;
 667                }
 668        }
 669        if (i < 0)
 670                seq_printf(seq, "0x%02x (undefined)\n", nvram[1]);
 671
 672        seq_printf(seq, "SCSI arbitration : %s\n",
 673            (nvram[16] & 0x80) ? "on" : "off");
 674        seq_printf(seq, "SCSI host ID     : ");
 675        if (nvram[16] & 0x80)
 676                seq_printf(seq, "%d\n", nvram[16] & 7);
 677        else
 678                seq_printf(seq, "n/a\n");
 679
 680        /* the following entries are defined only for the Falcon */
 681        if ((atari_mch_cookie >> 16) != ATARI_MCH_FALCON)
 682                return;
 683
 684        seq_printf(seq, "OS language      : ");
 685        if (nvram[6] < ARRAY_SIZE(languages))
 686                seq_printf(seq, "%s\n", languages[nvram[6]]);
 687        else
 688                seq_printf(seq, "%u (undefined)\n", nvram[6]);
 689        seq_printf(seq, "Keyboard language: ");
 690        if (nvram[7] < ARRAY_SIZE(languages))
 691                seq_printf(seq, "%s\n", languages[nvram[7]]);
 692        else
 693                seq_printf(seq, "%u (undefined)\n", nvram[7]);
 694        seq_printf(seq, "Date format      : ");
 695        seq_printf(seq, dateformat[nvram[8] & 7],
 696            nvram[9] ? nvram[9] : '/', nvram[9] ? nvram[9] : '/');
 697        seq_printf(seq, ", %dh clock\n", nvram[8] & 16 ? 24 : 12);
 698        seq_printf(seq, "Boot delay       : ");
 699        if (nvram[10] == 0)
 700                seq_printf(seq, "default");
 701        else
 702                seq_printf(seq, "%ds%s\n", nvram[10],
 703                    nvram[10] < 8 ? ", no memory test" : "");
 704
 705        vmode = (nvram[14] << 8) || nvram[15];
 706        seq_printf(seq,
 707            "Video mode       : %s colors, %d columns, %s %s monitor\n",
 708            colors[vmode & 7],
 709            vmode & 8 ? 80 : 40,
 710            vmode & 16 ? "VGA" : "TV", vmode & 32 ? "PAL" : "NTSC");
 711        seq_printf(seq, "                   %soverscan, compat. mode %s%s\n",
 712            vmode & 64 ? "" : "no ",
 713            vmode & 128 ? "on" : "off",
 714            vmode & 256 ?
 715            (vmode & 16 ? ", line doubling" : ", half screen") : "");
 716
 717        return;
 718}
 719#endif
 720
 721#endif /* MACH == ATARI */
 722
 723MODULE_LICENSE("GPL");
 724MODULE_ALIAS_MISCDEV(NVRAM_MINOR);
 725
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