arch/sparc64/kernel/time.c

   1 /* $Id: time.c,v 1.42 2002/01/23 14:33:55 davem Exp $
   2  * time.c: UltraSparc timer and TOD clock support.
   3  *
   4  * Copyright (C) 1997 David S. Miller (davem@caip.rutgers.edu)
   5  * Copyright (C) 1998 Eddie C. Dost   (ecd@skynet.be)
   6  *
   7  * Based largely on code which is:
   8  *
   9  * Copyright (C) 1996 Thomas K. Dyas (tdyas@eden.rutgers.edu)
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/errno.h>
  14 #include <linux/module.h>
  15 #include <linux/sched.h>
  16 #include <linux/kernel.h>
  17 #include <linux/param.h>
  18 #include <linux/string.h>
  19 #include <linux/mm.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/time.h>
  22 #include <linux/timex.h>
  23 #include <linux/init.h>
  24 #include <linux/ioport.h>
  25 #include <linux/mc146818rtc.h>
  26 #include <linux/delay.h>
  27 #include <linux/profile.h>
  28 #include <linux/bcd.h>
  29 #include <linux/jiffies.h>
  30 #include <linux/cpufreq.h>
  31 #include <linux/percpu.h>
  32 #include <linux/profile.h>
  33 #include <linux/miscdevice.h>
  34 #include <linux/rtc.h>
  35
  36 #include <asm/oplib.h>
  37 #include <asm/mostek.h>
  38 #include <asm/timer.h>
  39 #include <asm/irq.h>
  40 #include <asm/io.h>
  41 #include <asm/sbus.h>
  42 #include <asm/fhc.h>
  43 #include <asm/pbm.h>
  44 #include <asm/ebus.h>
  45 #include <asm/isa.h>
  46 #include <asm/starfire.h>
  47 #include <asm/smp.h>
  48 #include <asm/sections.h>
  49 #include <asm/cpudata.h>
  50 #include <asm/uaccess.h>
  51 #include <asm/prom.h>
  52
  53 DEFINE_SPINLOCK(mostek_lock);
  54 DEFINE_SPINLOCK(rtc_lock);
  55 void __iomem *mstk48t02_regs = NULL;
  56 #ifdef CONFIG_PCI
  57 unsigned long ds1287_regs = 0UL;
  58 #endif
  59
  60 extern unsigned long wall_jiffies;
  61
  62 static void __iomem *mstk48t08_regs;
  63 static void __iomem *mstk48t59_regs;
  64
  65 static int set_rtc_mmss(unsigned long);
  66
  67 #define TICK_PRIV_BIT   (1UL << 63)
  68
  69 #ifdef CONFIG_SMP
  70 unsigned long profile_pc(struct pt_regs *regs)
  71 {
  72         unsigned long pc = instruction_pointer(regs);
  73
  74         if (in_lock_functions(pc))
  75                 return regs->u_regs[UREG_RETPC];
  76         return pc;
  77 }
  78 EXPORT_SYMBOL(profile_pc);
  79 #endif
  80
  81 static void tick_disable_protection(void)
  82 {
  83         /* Set things up so user can access tick register for profiling
  84          * purposes.  Also workaround BB_ERRATA_1 by doing a dummy
  85          * read back of %tick after writing it.
  86          */
  87         __asm__ __volatile__(
  88         "       ba,pt   %%xcc, 1f\n"
  89         "        nop\n"
  90         "       .align  64\n"
  91         "1:     rd      %%tick, %%g2\n"
  92         "       add     %%g2, 6, %%g2\n"
  93         "       andn    %%g2, %0, %%g2\n"
  94         "       wrpr    %%g2, 0, %%tick\n"
  95         "       rdpr    %%tick, %%g0"
  96         : /* no outputs */
  97         : "r" (TICK_PRIV_BIT)
  98         : "g2");
  99 }
 100
 101 static void tick_init_tick(unsigned long offset)
 102 {
 103         tick_disable_protection();
 104
 105         __asm__ __volatile__(
 106         "       rd      %%tick, %%g1\n"
 107         "       andn    %%g1, %1, %%g1\n"
 108         "       ba,pt   %%xcc, 1f\n"
 109         "        add    %%g1, %0, %%g1\n"
 110         "       .align  64\n"
 111         "1:     wr      %%g1, 0x0, %%tick_cmpr\n"
 112         "       rd      %%tick_cmpr, %%g0"
 113         : /* no outputs */
 114         : "r" (offset), "r" (TICK_PRIV_BIT)
 115         : "g1");
 116 }
 117
 118 static unsigned long tick_get_tick(void)
 119 {
 120         unsigned long ret;
 121
 122         __asm__ __volatile__("rd        %%tick, %0\n\t"
 123                              "mov       %0, %0"
 124                              : "=r" (ret));
 125
 126         return ret & ~TICK_PRIV_BIT;
 127 }
 128
 129 static unsigned long tick_get_compare(void)
 130 {
 131         unsigned long ret;
 132
 133         __asm__ __volatile__("rd        %%tick_cmpr, %0\n\t"
 134                              "mov       %0, %0"
 135                              : "=r" (ret));
 136
 137         return ret;
 138 }
 139
 140 static unsigned long tick_add_compare(unsigned long adj)
 141 {
 142         unsigned long new_compare;
 143
 144         /* Workaround for Spitfire Errata (#54 I think??), I discovered
 145          * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
 146          * number 103640.
 147          *
 148          * On Blackbird writes to %tick_cmpr can fail, the
 149          * workaround seems to be to execute the wr instruction
 150          * at the start of an I-cache line, and perform a dummy
 151          * read back from %tick_cmpr right after writing to it. -DaveM
 152          */
 153         __asm__ __volatile__("rd        %%tick_cmpr, %0\n\t"
 154                              "ba,pt     %%xcc, 1f\n\t"
 155                              " add      %0, %1, %0\n\t"
 156                              ".align    64\n"
 157                              "1:\n\t"
 158                              "wr        %0, 0, %%tick_cmpr\n\t"
 159                              "rd        %%tick_cmpr, %%g0"
 160                              : "=&r" (new_compare)
 161                              : "r" (adj));
 162
 163         return new_compare;
 164 }
 165
 166 static unsigned long tick_add_tick(unsigned long adj, unsigned long offset)
 167 {
 168         unsigned long new_tick, tmp;
 169
 170         /* Also need to handle Blackbird bug here too. */
 171         __asm__ __volatile__("rd        %%tick, %0\n\t"
 172                              "add       %0, %2, %0\n\t"
 173                              "wrpr      %0, 0, %%tick\n\t"
 174                              "andn      %0, %4, %1\n\t"
 175                              "ba,pt     %%xcc, 1f\n\t"
 176                              " add      %1, %3, %1\n\t"
 177                              ".align    64\n"
 178                              "1:\n\t"
 179                              "wr        %1, 0, %%tick_cmpr\n\t"
 180                              "rd        %%tick_cmpr, %%g0"
 181                              : "=&r" (new_tick), "=&r" (tmp)
 182                              : "r" (adj), "r" (offset), "r" (TICK_PRIV_BIT));
 183
 184         return new_tick;
 185 }
 186
 187 static struct sparc64_tick_ops tick_operations __read_mostly = {
 188         .init_tick      =       tick_init_tick,
 189         .get_tick       =       tick_get_tick,
 190         .get_compare    =       tick_get_compare,
 191         .add_tick       =       tick_add_tick,
 192         .add_compare    =       tick_add_compare,
 193         .softint_mask   =       1UL << 0,
 194 };
 195
 196 struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
 197
 198 static void stick_init_tick(unsigned long offset)
 199 {
 200         /* Writes to the %tick and %stick register are not
 201          * allowed on sun4v.  The Hypervisor controls that
 202          * bit, per-strand.
 203          */
 204         if (tlb_type != hypervisor) {
 205                 tick_disable_protection();
 206
 207                 /* Let the user get at STICK too. */
 208                 __asm__ __volatile__(
 209                 "       rd      %%asr24, %%g2\n"
 210                 "       andn    %%g2, %0, %%g2\n"
 211                 "       wr      %%g2, 0, %%asr24"
 212                 : /* no outputs */
 213                 : "r" (TICK_PRIV_BIT)
 214                 : "g1", "g2");
 215         }
 216
 217         __asm__ __volatile__(
 218         "       rd      %%asr24, %%g1\n"
 219         "       andn    %%g1, %1, %%g1\n"
 220         "       add     %%g1, %0, %%g1\n"
 221         "       wr      %%g1, 0x0, %%asr25"
 222         : /* no outputs */
 223         : "r" (offset), "r" (TICK_PRIV_BIT)
 224         : "g1");
 225 }
 226
 227 static unsigned long stick_get_tick(void)
 228 {
 229         unsigned long ret;
 230
 231         __asm__ __volatile__("rd        %%asr24, %0"
 232                              : "=r" (ret));
 233
 234         return ret & ~TICK_PRIV_BIT;
 235 }
 236
 237 static unsigned long stick_get_compare(void)
 238 {
 239         unsigned long ret;
 240
 241         __asm__ __volatile__("rd        %%asr25, %0"
 242                              : "=r" (ret));
 243
 244         return ret;
 245 }
 246
 247 static unsigned long stick_add_tick(unsigned long adj, unsigned long offset)
 248 {
 249         unsigned long new_tick, tmp;
 250
 251         __asm__ __volatile__("rd        %%asr24, %0\n\t"
 252                              "add       %0, %2, %0\n\t"
 253                              "wr        %0, 0, %%asr24\n\t"
 254                              "andn      %0, %4, %1\n\t"
 255                              "add       %1, %3, %1\n\t"
 256                              "wr        %1, 0, %%asr25"
 257                              : "=&r" (new_tick), "=&r" (tmp)
 258                              : "r" (adj), "r" (offset), "r" (TICK_PRIV_BIT));
 259
 260         return new_tick;
 261 }
 262
 263 static unsigned long stick_add_compare(unsigned long adj)
 264 {
 265         unsigned long new_compare;
 266
 267         __asm__ __volatile__("rd        %%asr25, %0\n\t"
 268                              "add       %0, %1, %0\n\t"
 269                              "wr        %0, 0, %%asr25"
 270                              : "=&r" (new_compare)
 271                              : "r" (adj));
 272
 273         return new_compare;
 274 }
 275
 276 static struct sparc64_tick_ops stick_operations __read_mostly = {
 277         .init_tick      =       stick_init_tick,
 278         .get_tick       =       stick_get_tick,
 279         .get_compare    =       stick_get_compare,
 280         .add_tick       =       stick_add_tick,
 281         .add_compare    =       stick_add_compare,
 282         .softint_mask   =       1UL << 16,
 283 };
 284
 285 /* On Hummingbird the STICK/STICK_CMPR register is implemented
 286  * in I/O space.  There are two 64-bit registers each, the
 287  * first holds the low 32-bits of the value and the second holds
 288  * the high 32-bits.
 289  *
 290  * Since STICK is constantly updating, we have to access it carefully.
 291  *
 292  * The sequence we use to read is:
 293  * 1) read high
 294  * 2) read low
 295  * 3) read high again, if it rolled re-read both low and high again.
 296  *
 297  * Writing STICK safely is also tricky:
 298  * 1) write low to zero
 299  * 2) write high
 300  * 3) write low
 301  */
 302 #define HBIRD_STICKCMP_ADDR     0x1fe0000f060UL
 303 #define HBIRD_STICK_ADDR        0x1fe0000f070UL
 304
 305 static unsigned long __hbird_read_stick(void)
 306 {
 307         unsigned long ret, tmp1, tmp2, tmp3;
 308         unsigned long addr = HBIRD_STICK_ADDR+8;
 309
 310         __asm__ __volatile__("ldxa      [%1] %5, %2\n"
 311                              "1:\n\t"
 312                              "sub       %1, 0x8, %1\n\t"
 313                              "ldxa      [%1] %5, %3\n\t"
 314                              "add       %1, 0x8, %1\n\t"
 315                              "ldxa      [%1] %5, %4\n\t"
 316                              "cmp       %4, %2\n\t"
 317                              "bne,a,pn  %%xcc, 1b\n\t"
 318                              " mov      %4, %2\n\t"
 319                              "sllx      %4, 32, %4\n\t"
 320                              "or        %3, %4, %0\n\t"
 321                              : "=&r" (ret), "=&r" (addr),
 322                                "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
 323                              : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));
 324
 325         return ret;
 326 }
 327
 328 static unsigned long __hbird_read_compare(void)
 329 {
 330         unsigned long low, high;
 331         unsigned long addr = HBIRD_STICKCMP_ADDR;
 332
 333         __asm__ __volatile__("ldxa      [%2] %3, %0\n\t"
 334                              "add       %2, 0x8, %2\n\t"
 335                              "ldxa      [%2] %3, %1"
 336                              : "=&r" (low), "=&r" (high), "=&r" (addr)
 337                              : "i" (ASI_PHYS_BYPASS_EC_E), "2" (addr));
 338
 339         return (high << 32UL) | low;
 340 }
 341
 342 static void __hbird_write_stick(unsigned long val)
 343 {
 344         unsigned long low = (val & 0xffffffffUL);
 345         unsigned long high = (val >> 32UL);
 346         unsigned long addr = HBIRD_STICK_ADDR;
 347
 348         __asm__ __volatile__("stxa      %%g0, [%0] %4\n\t"
 349                              "add       %0, 0x8, %0\n\t"
 350                              "stxa      %3, [%0] %4\n\t"
 351                              "sub       %0, 0x8, %0\n\t"
 352                              "stxa      %2, [%0] %4"
 353                              : "=&r" (addr)
 354                              : "0" (addr), "r" (low), "r" (high),
 355                                "i" (ASI_PHYS_BYPASS_EC_E));
 356 }
 357
 358 static void __hbird_write_compare(unsigned long val)
 359 {
 360         unsigned long low = (val & 0xffffffffUL);
 361         unsigned long high = (val >> 32UL);
 362         unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;
 363
 364         __asm__ __volatile__("stxa      %3, [%0] %4\n\t"
 365                              "sub       %0, 0x8, %0\n\t"
 366                              "stxa      %2, [%0] %4"
 367                              : "=&r" (addr)
 368                              : "0" (addr), "r" (low), "r" (high),
 369                                "i" (ASI_PHYS_BYPASS_EC_E));
 370 }
 371
 372 static void hbtick_init_tick(unsigned long offset)
 373 {
 374         unsigned long val;
 375
 376         tick_disable_protection();
 377
 378         /* XXX This seems to be necessary to 'jumpstart' Hummingbird
 379          * XXX into actually sending STICK interrupts.  I think because
 380          * XXX of how we store %tick_cmpr in head.S this somehow resets the
 381          * XXX {TICK + STICK} interrupt mux.  -DaveM
 382          */
 383         __hbird_write_stick(__hbird_read_stick());
 384
 385         val = __hbird_read_stick() & ~TICK_PRIV_BIT;
 386         __hbird_write_compare(val + offset);
 387 }
 388
 389 static unsigned long hbtick_get_tick(void)
 390 {
 391         return __hbird_read_stick() & ~TICK_PRIV_BIT;
 392 }
 393
 394 static unsigned long hbtick_get_compare(void)
 395 {
 396         return __hbird_read_compare();
 397 }
 398
 399 static unsigned long hbtick_add_tick(unsigned long adj, unsigned long offset)
 400 {
 401         unsigned long val;
 402
 403         val = __hbird_read_stick() + adj;
 404         __hbird_write_stick(val);
 405
 406         val &= ~TICK_PRIV_BIT;
 407         __hbird_write_compare(val + offset);
 408
 409         return val;
 410 }
 411
 412 static unsigned long hbtick_add_compare(unsigned long adj)
 413 {
 414         unsigned long val = __hbird_read_compare() + adj;
 415
 416         val &= ~TICK_PRIV_BIT;
 417         __hbird_write_compare(val);
 418
 419         return val;
 420 }
 421
 422 static struct sparc64_tick_ops hbtick_operations __read_mostly = {
 423         .init_tick      =       hbtick_init_tick,
 424         .get_tick       =       hbtick_get_tick,
 425         .get_compare    =       hbtick_get_compare,
 426         .add_tick       =       hbtick_add_tick,
 427         .add_compare    =       hbtick_add_compare,
 428         .softint_mask   =       1UL << 0,
 429 };
 430
 431 /* timer_interrupt() needs to keep up the real-time clock,
 432  * as well as call the "do_timer()" routine every clocktick
 433  *
 434  * NOTE: On SUN5 systems the ticker interrupt comes in using 2
 435  *       interrupts, one at level14 and one with softint bit 0.
 436  */
 437 unsigned long timer_tick_offset __read_mostly;
 438
 439 static unsigned long timer_ticks_per_nsec_quotient __read_mostly;
 440
 441 #define TICK_SIZE (tick_nsec / 1000)
 442
 443 static inline void timer_check_rtc(void)
 444 {
 445         /* last time the cmos clock got updated */
 446         static long last_rtc_update;
 447
 448         /* Determine when to update the Mostek clock. */
 449         if (ntp_synced() &&
 450             xtime.tv_sec > last_rtc_update + 660 &&
 451             (xtime.tv_nsec / 1000) >= 500000 - ((unsigned) TICK_SIZE) / 2 &&
 452             (xtime.tv_nsec / 1000) <= 500000 + ((unsigned) TICK_SIZE) / 2) {
 453                 if (set_rtc_mmss(xtime.tv_sec) == 0)
 454                         last_rtc_update = xtime.tv_sec;
 455                 else
 456                         last_rtc_update = xtime.tv_sec - 600;
 457                         /* do it again in 60 s */
 458         }
 459 }
 460
 461 irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs * regs)
 462 {
 463         unsigned long ticks, compare, pstate;
 464
 465         write_seqlock(&xtime_lock);
 466
 467         do {
 468 #ifndef CONFIG_SMP
 469                 profile_tick(CPU_PROFILING, regs);
 470                 update_process_times(user_mode(regs));
 471 #endif
 472                 do_timer(regs);
 473
 474                 /* Guarantee that the following sequences execute
 475                  * uninterrupted.
 476                  */
 477                 __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 478                                      "wrpr      %0, %1, %%pstate"
 479                                      : "=r" (pstate)
 480                                      : "i" (PSTATE_IE));
 481
 482                 compare = tick_ops->add_compare(timer_tick_offset);
 483                 ticks = tick_ops->get_tick();
 484
 485                 /* Restore PSTATE_IE. */
 486                 __asm__ __volatile__("wrpr      %0, 0x0, %%pstate"
 487                                      : /* no outputs */
 488                                      : "r" (pstate));
 489         } while (time_after_eq(ticks, compare));
 490
 491         timer_check_rtc();
 492
 493         write_sequnlock(&xtime_lock);
 494
 495         return IRQ_HANDLED;
 496 }
 497
 498 #ifdef CONFIG_SMP
 499 void timer_tick_interrupt(struct pt_regs *regs)
 500 {
 501         write_seqlock(&xtime_lock);
 502
 503         do_timer(regs);
 504
 505         timer_check_rtc();
 506
 507         write_sequnlock(&xtime_lock);
 508 }
 509 #endif
 510
 511 /* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
 512 static void __init kick_start_clock(void)
 513 {
 514         void __iomem *regs = mstk48t02_regs;
 515         u8 sec, tmp;
 516         int i, count;
 517
 518         prom_printf("CLOCK: Clock was stopped. Kick start ");
 519
 520         spin_lock_irq(&mostek_lock);
 521
 522         /* Turn on the kick start bit to start the oscillator. */
 523         tmp = mostek_read(regs + MOSTEK_CREG);
 524         tmp |= MSTK_CREG_WRITE;
 525         mostek_write(regs + MOSTEK_CREG, tmp);
 526         tmp = mostek_read(regs + MOSTEK_SEC);
 527         tmp &= ~MSTK_STOP;
 528         mostek_write(regs + MOSTEK_SEC, tmp);
 529         tmp = mostek_read(regs + MOSTEK_HOUR);
 530         tmp |= MSTK_KICK_START;
 531         mostek_write(regs + MOSTEK_HOUR, tmp);
 532         tmp = mostek_read(regs + MOSTEK_CREG);
 533         tmp &= ~MSTK_CREG_WRITE;
 534         mostek_write(regs + MOSTEK_CREG, tmp);
 535
 536         spin_unlock_irq(&mostek_lock);
 537
 538         /* Delay to allow the clock oscillator to start. */
 539         sec = MSTK_REG_SEC(regs);
 540         for (i = 0; i < 3; i++) {
 541                 while (sec == MSTK_REG_SEC(regs))
 542                         for (count = 0; count < 100000; count++)
 543                                 /* nothing */ ;
 544                 prom_printf(".");
 545                 sec = MSTK_REG_SEC(regs);
 546         }
 547         prom_printf("\n");
 548
 549         spin_lock_irq(&mostek_lock);
 550
 551         /* Turn off kick start and set a "valid" time and date. */
 552         tmp = mostek_read(regs + MOSTEK_CREG);
 553         tmp |= MSTK_CREG_WRITE;
 554         mostek_write(regs + MOSTEK_CREG, tmp);
 555         tmp = mostek_read(regs + MOSTEK_HOUR);
 556         tmp &= ~MSTK_KICK_START;
 557         mostek_write(regs + MOSTEK_HOUR, tmp);
 558         MSTK_SET_REG_SEC(regs,0);
 559         MSTK_SET_REG_MIN(regs,0);
 560         MSTK_SET_REG_HOUR(regs,0);
 561         MSTK_SET_REG_DOW(regs,5);
 562         MSTK_SET_REG_DOM(regs,1);
 563         MSTK_SET_REG_MONTH(regs,8);
 564         MSTK_SET_REG_YEAR(regs,1996 - MSTK_YEAR_ZERO);
 565         tmp = mostek_read(regs + MOSTEK_CREG);
 566         tmp &= ~MSTK_CREG_WRITE;
 567         mostek_write(regs + MOSTEK_CREG, tmp);
 568
 569         spin_unlock_irq(&mostek_lock);
 570
 571         /* Ensure the kick start bit is off. If it isn't, turn it off. */
 572         while (mostek_read(regs + MOSTEK_HOUR) & MSTK_KICK_START) {
 573                 prom_printf("CLOCK: Kick start still on!\n");
 574
 575                 spin_lock_irq(&mostek_lock);
 576
 577                 tmp = mostek_read(regs + MOSTEK_CREG);
 578                 tmp |= MSTK_CREG_WRITE;
 579                 mostek_write(regs + MOSTEK_CREG, tmp);
 580
 581                 tmp = mostek_read(regs + MOSTEK_HOUR);
 582                 tmp &= ~MSTK_KICK_START;
 583                 mostek_write(regs + MOSTEK_HOUR, tmp);
 584
 585                 tmp = mostek_read(regs + MOSTEK_CREG);
 586                 tmp &= ~MSTK_CREG_WRITE;
 587                 mostek_write(regs + MOSTEK_CREG, tmp);
 588
 589                 spin_unlock_irq(&mostek_lock);
 590         }
 591
 592         prom_printf("CLOCK: Kick start procedure successful.\n");
 593 }
 594
 595 /* Return nonzero if the clock chip battery is low. */
 596 static int __init has_low_battery(void)
 597 {
 598         void __iomem *regs = mstk48t02_regs;
 599         u8 data1, data2;
 600
 601         spin_lock_irq(&mostek_lock);
 602
 603         data1 = mostek_read(regs + MOSTEK_EEPROM);      /* Read some data. */
 604         mostek_write(regs + MOSTEK_EEPROM, ~data1);     /* Write back the complement. */
 605         data2 = mostek_read(regs + MOSTEK_EEPROM);      /* Read back the complement. */
 606         mostek_write(regs + MOSTEK_EEPROM, data1);      /* Restore original value. */
 607
 608         spin_unlock_irq(&mostek_lock);
 609
 610         return (data1 == data2);        /* Was the write blocked? */
 611 }
 612
 613 /* Probe for the real time clock chip. */
 614 static void __init set_system_time(void)
 615 {
 616         unsigned int year, mon, day, hour, min, sec;
 617         void __iomem *mregs = mstk48t02_regs;
 618 #ifdef CONFIG_PCI
 619         unsigned long dregs = ds1287_regs;
 620 #else
 621         unsigned long dregs = 0UL;
 622 #endif
 623         u8 tmp;
 624
 625         if (!mregs && !dregs) {
 626                 prom_printf("Something wrong, clock regs not mapped yet.\n");
 627                 prom_halt();
 628         }
 629
 630         if (mregs) {
 631                 spin_lock_irq(&mostek_lock);
 632
 633                 /* Traditional Mostek chip. */
 634                 tmp = mostek_read(mregs + MOSTEK_CREG);
 635                 tmp |= MSTK_CREG_READ;
 636                 mostek_write(mregs + MOSTEK_CREG, tmp);
 637
 638                 sec = MSTK_REG_SEC(mregs);
 639                 min = MSTK_REG_MIN(mregs);
 640                 hour = MSTK_REG_HOUR(mregs);
 641                 day = MSTK_REG_DOM(mregs);
 642                 mon = MSTK_REG_MONTH(mregs);
 643                 year = MSTK_CVT_YEAR( MSTK_REG_YEAR(mregs) );
 644         } else {
 645                 /* Dallas 12887 RTC chip. */
 646
 647                 do {
 648                         sec  = CMOS_READ(RTC_SECONDS);
 649                         min  = CMOS_READ(RTC_MINUTES);
 650                         hour = CMOS_READ(RTC_HOURS);
 651                         day  = CMOS_READ(RTC_DAY_OF_MONTH);
 652                         mon  = CMOS_READ(RTC_MONTH);
 653                         year = CMOS_READ(RTC_YEAR);
 654                 } while (sec != CMOS_READ(RTC_SECONDS));
 655
 656                 if (!(CMOS_READ(RTC_CONTROL) & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
 657                         BCD_TO_BIN(sec);
 658                         BCD_TO_BIN(min);
 659                         BCD_TO_BIN(hour);
 660                         BCD_TO_BIN(day);
 661                         BCD_TO_BIN(mon);
 662                         BCD_TO_BIN(year);
 663                 }
 664                 if ((year += 1900) < 1970)
 665                         year += 100;
 666         }
 667
 668         xtime.tv_sec = mktime(year, mon, day, hour, min, sec);
 669         xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
 670         set_normalized_timespec(&wall_to_monotonic,
 671                                 -xtime.tv_sec, -xtime.tv_nsec);
 672
 673         if (mregs) {
 674                 tmp = mostek_read(mregs + MOSTEK_CREG);
 675                 tmp &= ~MSTK_CREG_READ;
 676                 mostek_write(mregs + MOSTEK_CREG, tmp);
 677
 678                 spin_unlock_irq(&mostek_lock);
 679         }
 680 }
 681
 682 /* davem suggests we keep this within the 4M locked kernel image */
 683 static u32 starfire_get_time(void)
 684 {
 685         static char obp_gettod[32];
 686         static u32 unix_tod;
 687
 688         sprintf(obp_gettod, "h# %08x unix-gettod",
 689                 (unsigned int) (long) &unix_tod);
 690         prom_feval(obp_gettod);
 691
 692         return unix_tod;
 693 }
 694
 695 static int starfire_set_time(u32 val)
 696 {
 697         /* Do nothing, time is set using the service processor
 698          * console on this platform.
 699          */
 700         return 0;
 701 }
 702
 703 static u32 hypervisor_get_time(void)
 704 {
 705         register unsigned long func asm("%o5");
 706         register unsigned long arg0 asm("%o0");
 707         register unsigned long arg1 asm("%o1");
 708         int retries = 10000;
 709
 710 retry:
 711         func = HV_FAST_TOD_GET;
 712         arg0 = 0;
 713         arg1 = 0;
 714         __asm__ __volatile__("ta        %6"
 715                              : "=&r" (func), "=&r" (arg0), "=&r" (arg1)
 716                              : "0" (func), "1" (arg0), "2" (arg1),
 717                                "i" (HV_FAST_TRAP));
 718         if (arg0 == HV_EOK)
 719                 return arg1;
 720         if (arg0 == HV_EWOULDBLOCK) {
 721                 if (--retries > 0) {
 722                         udelay(100);
 723                         goto retry;
 724                 }
 725                 printk(KERN_WARNING "SUN4V: tod_get() timed out.\n");
 726                 return 0;
 727         }
 728         printk(KERN_WARNING "SUN4V: tod_get() not supported.\n");
 729         return 0;
 730 }
 731
 732 static int hypervisor_set_time(u32 secs)
 733 {
 734         register unsigned long func asm("%o5");
 735         register unsigned long arg0 asm("%o0");
 736         int retries = 10000;
 737
 738 retry:
 739         func = HV_FAST_TOD_SET;
 740         arg0 = secs;
 741         __asm__ __volatile__("ta        %4"
 742                              : "=&r" (func), "=&r" (arg0)
 743                              : "0" (func), "1" (arg0),
 744                                "i" (HV_FAST_TRAP));
 745         if (arg0 == HV_EOK)
 746                 return 0;
 747         if (arg0 == HV_EWOULDBLOCK) {
 748                 if (--retries > 0) {
 749                         udelay(100);
 750                         goto retry;
 751                 }
 752                 printk(KERN_WARNING "SUN4V: tod_set() timed out.\n");
 753                 return -EAGAIN;
 754         }
 755         printk(KERN_WARNING "SUN4V: tod_set() not supported.\n");
 756         return -EOPNOTSUPP;
 757 }
 758
 759 void __init clock_probe(void)
 760 {
 761         struct linux_prom_registers clk_reg[2];
 762         char model[128];
 763         int node, busnd = -1, err;
 764         unsigned long flags;
 765         struct linux_central *cbus;
 766 #ifdef CONFIG_PCI
 767         struct linux_ebus *ebus = NULL;
 768         struct sparc_isa_bridge *isa_br = NULL;
 769 #endif
 770         static int invoked;
 771
 772         if (invoked)
 773                 return;
 774         invoked = 1;
 775
 776
 777         if (this_is_starfire) {
 778                 xtime.tv_sec = starfire_get_time();
 779                 xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
 780                 set_normalized_timespec(&wall_to_monotonic,
 781                                         -xtime.tv_sec, -xtime.tv_nsec);
 782                 return;
 783         }
 784         if (tlb_type == hypervisor) {
 785                 xtime.tv_sec = hypervisor_get_time();
 786                 xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
 787                 set_normalized_timespec(&wall_to_monotonic,
 788                                         -xtime.tv_sec, -xtime.tv_nsec);
 789                 return;
 790         }
 791
 792         local_irq_save(flags);
 793
 794         cbus = central_bus;
 795         if (cbus != NULL)
 796                 busnd = central_bus->child->prom_node;
 797
 798         /* Check FHC Central then EBUSs then ISA bridges then SBUSs.
 799          * That way we handle the presence of multiple properly.
 800          *
 801          * As a special case, machines with Central must provide the
 802          * timer chip there.
 803          */
 804 #ifdef CONFIG_PCI
 805         if (ebus_chain != NULL) {
 806                 ebus = ebus_chain;
 807                 if (busnd == -1)
 808                         busnd = ebus->prom_node;
 809         }
 810         if (isa_chain != NULL) {
 811                 isa_br = isa_chain;
 812                 if (busnd == -1)
 813                         busnd = isa_br->prom_node;
 814         }
 815 #endif
 816         if (sbus_root != NULL && busnd == -1)
 817                 busnd = sbus_root->prom_node;
 818
 819         if (busnd == -1) {
 820                 prom_printf("clock_probe: problem, cannot find bus to search.\n");
 821                 prom_halt();
 822         }
 823
 824         node = prom_getchild(busnd);
 825
 826         while (1) {
 827                 if (!node)
 828                         model[0] = 0;
 829                 else
 830                         prom_getstring(node, "model", model, sizeof(model));
 831                 if (strcmp(model, "mk48t02") &&
 832                     strcmp(model, "mk48t08") &&
 833                     strcmp(model, "mk48t59") &&
 834                     strcmp(model, "m5819") &&
 835                     strcmp(model, "m5819p") &&
 836                     strcmp(model, "m5823") &&
 837                     strcmp(model, "ds1287")) {
 838                         if (cbus != NULL) {
 839                                 prom_printf("clock_probe: Central bus lacks timer chip.\n");
 840                                 prom_halt();
 841                         }
 842
 843                         if (node != 0)
 844                                 node = prom_getsibling(node);
 845 #ifdef CONFIG_PCI
 846                         while ((node == 0) && ebus != NULL) {
 847                                 ebus = ebus->next;
 848                                 if (ebus != NULL) {
 849                                         busnd = ebus->prom_node;
 850                                         node = prom_getchild(busnd);
 851                                 }
 852                         }
 853                         while ((node == 0) && isa_br != NULL) {
 854                                 isa_br = isa_br->next;
 855                                 if (isa_br != NULL) {
 856                                         busnd = isa_br->prom_node;
 857                                         node = prom_getchild(busnd);
 858                                 }
 859                         }
 860 #endif
 861                         if (node == 0) {
 862                                 prom_printf("clock_probe: Cannot find timer chip\n");
 863                                 prom_halt();
 864                         }
 865                         continue;
 866                 }
 867
 868                 err = prom_getproperty(node, "reg", (char *)clk_reg,
 869                                        sizeof(clk_reg));
 870                 if(err == -1) {
 871                         prom_printf("clock_probe: Cannot get Mostek reg property\n");
 872                         prom_halt();
 873                 }
 874
 875                 if (cbus != NULL) {
 876                         apply_fhc_ranges(central_bus->child, clk_reg, 1);
 877                         apply_central_ranges(central_bus, clk_reg, 1);
 878                 }
 879 #ifdef CONFIG_PCI
 880                 else if (ebus != NULL) {
 881                         struct linux_ebus_device *edev;
 882
 883                         for_each_ebusdev(edev, ebus)
 884                                 if (edev->prom_node == node)
 885                                         break;
 886                         if (edev == NULL) {
 887                                 if (isa_chain != NULL)
 888                                         goto try_isa_clock;
 889                                 prom_printf("%s: Mostek not probed by EBUS\n",
 890                                             __FUNCTION__);
 891                                 prom_halt();
 892                         }
 893
 894                         if (!strcmp(model, "ds1287") ||
 895                             !strcmp(model, "m5819") ||
 896                             !strcmp(model, "m5819p") ||
 897                             !strcmp(model, "m5823")) {
 898                                 ds1287_regs = edev->resource[0].start;
 899                         } else {
 900                                 mstk48t59_regs = (void __iomem *)
 901                                         edev->resource[0].start;
 902                                 mstk48t02_regs = mstk48t59_regs + MOSTEK_48T59_48T02;
 903                         }
 904                         break;
 905                 }
 906                 else if (isa_br != NULL) {
 907                         struct sparc_isa_device *isadev;
 908
 909 try_isa_clock:
 910                         for_each_isadev(isadev, isa_br)
 911                                 if (isadev->prom_node == node)
 912                                         break;
 913                         if (isadev == NULL) {
 914                                 prom_printf("%s: Mostek not probed by ISA\n");
 915                                 prom_halt();
 916                         }
 917                         if (!strcmp(model, "ds1287") ||
 918                             !strcmp(model, "m5819") ||
 919                             !strcmp(model, "m5819p") ||
 920                             !strcmp(model, "m5823")) {
 921                                 ds1287_regs = isadev->resource.start;
 922                         } else {
 923                                 mstk48t59_regs = (void __iomem *)
 924                                         isadev->resource.start;
 925                                 mstk48t02_regs = mstk48t59_regs + MOSTEK_48T59_48T02;
 926                         }
 927                         break;
 928                 }
 929 #endif
 930                 else {
 931                         if (sbus_root->num_sbus_ranges) {
 932                                 int nranges = sbus_root->num_sbus_ranges;
 933                                 int rngc;
 934
 935                                 for (rngc = 0; rngc < nranges; rngc++)
 936                                         if (clk_reg[0].which_io ==
 937                                             sbus_root->sbus_ranges[rngc].ot_child_space)
 938                                                 break;
 939                                 if (rngc == nranges) {
 940                                         prom_printf("clock_probe: Cannot find ranges for "
 941                                                     "clock regs.\n");
 942                                         prom_halt();
 943                                 }
 944                                 clk_reg[0].which_io =
 945                                         sbus_root->sbus_ranges[rngc].ot_parent_space;
 946                                 clk_reg[0].phys_addr +=
 947                                         sbus_root->sbus_ranges[rngc].ot_parent_base;
 948                         }
 949                 }
 950
 951                 if(model[5] == '0' && model[6] == '2') {
 952                         mstk48t02_regs = (void __iomem *)
 953                                 (((u64)clk_reg[0].phys_addr) |
 954                                  (((u64)clk_reg[0].which_io)<<32UL));
 955                 } else if(model[5] == '0' && model[6] == '8') {
 956                         mstk48t08_regs = (void __iomem *)
 957                                 (((u64)clk_reg[0].phys_addr) |
 958                                  (((u64)clk_reg[0].which_io)<<32UL));
 959                         mstk48t02_regs = mstk48t08_regs + MOSTEK_48T08_48T02;
 960                 } else {
 961                         mstk48t59_regs = (void __iomem *)
 962                                 (((u64)clk_reg[0].phys_addr) |
 963                                  (((u64)clk_reg[0].which_io)<<32UL));
 964                         mstk48t02_regs = mstk48t59_regs + MOSTEK_48T59_48T02;
 965                 }
 966                 break;
 967         }
 968
 969         if (mstk48t02_regs != NULL) {
 970                 /* Report a low battery voltage condition. */
 971                 if (has_low_battery())
 972                         prom_printf("NVRAM: Low battery voltage!\n");
 973
 974                 /* Kick start the clock if it is completely stopped. */
 975                 if (mostek_read(mstk48t02_regs + MOSTEK_SEC) & MSTK_STOP)
 976                         kick_start_clock();
 977         }
 978
 979         set_system_time();
 980
 981         local_irq_restore(flags);
 982 }
 983
 984 /* This is gets the master TICK_INT timer going. */
 985 static unsigned long sparc64_init_timers(void)
 986 {
 987         struct device_node *dp;
 988         struct property *prop;
 989         unsigned long clock;
 990 #ifdef CONFIG_SMP
 991         extern void smp_tick_init(void);
 992 #endif
 993
 994         dp = of_find_node_by_path("/");
 995         if (tlb_type == spitfire) {
 996                 unsigned long ver, manuf, impl;
 997
 998                 __asm__ __volatile__ ("rdpr %%ver, %0"
 999                                       : "=&r" (ver));
1000                 manuf = ((ver >> 48) & 0xffff);
1001                 impl = ((ver >> 32) & 0xffff);
1002                 if (manuf == 0x17 && impl == 0x13) {
1003                         /* Hummingbird, aka Ultra-IIe */
1004                         tick_ops = &hbtick_operations;
1005                         prop = of_find_property(dp, "stick-frequency", NULL);
1006                 } else {
1007                         tick_ops = &tick_operations;
1008                         cpu_find_by_instance(0, &dp, NULL);
1009                         prop = of_find_property(dp, "clock-frequency", NULL);
1010                 }
1011         } else {
1012                 tick_ops = &stick_operations;
1013                 prop = of_find_property(dp, "stick-frequency", NULL);
1014         }
1015         clock = *(unsigned int *) prop->value;
1016         timer_tick_offset = clock / HZ;
1017
1018 #ifdef CONFIG_SMP
1019         smp_tick_init();
1020 #endif
1021
1022         return clock;
1023 }
1024
1025 static void sparc64_start_timers(void)
1026 {
1027         unsigned long pstate;
1028
1029         /* Guarantee that the following sequences execute
1030          * uninterrupted.
1031          */
1032         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
1033                              "wrpr      %0, %1, %%pstate"
1034                              : "=r" (pstate)
1035                              : "i" (PSTATE_IE));
1036
1037         tick_ops->init_tick(timer_tick_offset);
1038
1039         /* Restore PSTATE_IE. */
1040         __asm__ __volatile__("wrpr      %0, 0x0, %%pstate"
1041                              : /* no outputs */
1042                              : "r" (pstate));
1043
1044         local_irq_enable();
1045 }
1046
1047 struct freq_table {
1048         unsigned long clock_tick_ref;
1049         unsigned int ref_freq;
1050 };
1051 static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
1052
1053 unsigned long sparc64_get_clock_tick(unsigned int cpu)
1054 {
1055         struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
1056
1057         if (ft->clock_tick_ref)
1058                 return ft->clock_tick_ref;
1059         return cpu_data(cpu).clock_tick;
1060 }
1061
1062 #ifdef CONFIG_CPU_FREQ
1063
1064 static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
1065                                     void *data)
1066 {
1067         struct cpufreq_freqs *freq = data;
1068         unsigned int cpu = freq->cpu;
1069         struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
1070
1071         if (!ft->ref_freq) {
1072                 ft->ref_freq = freq->old;
1073                 ft->clock_tick_ref = cpu_data(cpu).clock_tick;
1074         }
1075         if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
1076             (val == CPUFREQ_POSTCHANGE && freq->old > freq->new) ||
1077             (val == CPUFREQ_RESUMECHANGE)) {
1078                 cpu_data(cpu).clock_tick =
1079                         cpufreq_scale(ft->clock_tick_ref,
1080                                       ft->ref_freq,
1081                                       freq->new);
1082         }
1083
1084         return 0;
1085 }
1086
1087 static struct notifier_block sparc64_cpufreq_notifier_block = {
1088         .notifier_call  = sparc64_cpufreq_notifier
1089 };
1090
1091 #endif /* CONFIG_CPU_FREQ */
1092
1093 static struct time_interpolator sparc64_cpu_interpolator = {
1094         .source         =       TIME_SOURCE_CPU,
1095         .shift          =       16,
1096         .mask           =       0xffffffffffffffffLL
1097 };
1098
1099 /* The quotient formula is taken from the IA64 port. */
1100 #define SPARC64_NSEC_PER_CYC_SHIFT      30UL
1101 void __init time_init(void)
1102 {
1103         unsigned long clock = sparc64_init_timers();
1104
1105         sparc64_cpu_interpolator.frequency = clock;
1106         register_time_interpolator(&sparc64_cpu_interpolator);
1107
1108         /* Now that the interpolator is registered, it is
1109          * safe to start the timer ticking.
1110          */
1111         sparc64_start_timers();
1112
1113         timer_ticks_per_nsec_quotient =
1114                 (((NSEC_PER_SEC << SPARC64_NSEC_PER_CYC_SHIFT) +
1115                   (clock / 2)) / clock);
1116
1117 #ifdef CONFIG_CPU_FREQ
1118         cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
1119                                   CPUFREQ_TRANSITION_NOTIFIER);
1120 #endif
1121 }
1122
1123 unsigned long long sched_clock(void)
1124 {
1125         unsigned long ticks = tick_ops->get_tick();
1126
1127         return (ticks * timer_ticks_per_nsec_quotient)
1128                 >> SPARC64_NSEC_PER_CYC_SHIFT;
1129 }
1130
1131 static int set_rtc_mmss(unsigned long nowtime)
1132 {
1133         int real_seconds, real_minutes, chip_minutes;
1134         void __iomem *mregs = mstk48t02_regs;
1135 #ifdef CONFIG_PCI
1136         unsigned long dregs = ds1287_regs;
1137 #else
1138         unsigned long dregs = 0UL;
1139 #endif
1140         unsigned long flags;
1141         u8 tmp;
1142
1143         /*
1144          * Not having a register set can lead to trouble.
1145          * Also starfire doesn't have a tod clock.
1146          */
1147         if (!mregs && !dregs)
1148                 return -1;
1149
1150         if (mregs) {
1151                 spin_lock_irqsave(&mostek_lock, flags);
1152
1153                 /* Read the current RTC minutes. */
1154                 tmp = mostek_read(mregs + MOSTEK_CREG);
1155                 tmp |= MSTK_CREG_READ;
1156                 mostek_write(mregs + MOSTEK_CREG, tmp);
1157
1158                 chip_minutes = MSTK_REG_MIN(mregs);
1159
1160                 tmp = mostek_read(mregs + MOSTEK_CREG);
1161                 tmp &= ~MSTK_CREG_READ;
1162                 mostek_write(mregs + MOSTEK_CREG, tmp);
1163
1164                 /*
1165                  * since we're only adjusting minutes and seconds,
1166                  * don't interfere with hour overflow. This avoids
1167                  * messing with unknown time zones but requires your
1168                  * RTC not to be off by more than 15 minutes
1169                  */
1170                 real_seconds = nowtime % 60;
1171                 real_minutes = nowtime / 60;
1172                 if (((abs(real_minutes - chip_minutes) + 15)/30) & 1)
1173                         real_minutes += 30;     /* correct for half hour time zone */
1174                 real_minutes %= 60;
1175
1176                 if (abs(real_minutes - chip_minutes) < 30) {
1177                         tmp = mostek_read(mregs + MOSTEK_CREG);
1178                         tmp |= MSTK_CREG_WRITE;
1179                         mostek_write(mregs + MOSTEK_CREG, tmp);
1180
1181                         MSTK_SET_REG_SEC(mregs,real_seconds);
1182                         MSTK_SET_REG_MIN(mregs,real_minutes);
1183
1184                         tmp = mostek_read(mregs + MOSTEK_CREG);
1185                         tmp &= ~MSTK_CREG_WRITE;
1186                         mostek_write(mregs + MOSTEK_CREG, tmp);
1187
1188                         spin_unlock_irqrestore(&mostek_lock, flags);
1189
1190                         return 0;
1191                 } else {
1192                         spin_unlock_irqrestore(&mostek_lock, flags);
1193
1194                         return -1;
1195                 }
1196         } else {
1197                 int retval = 0;
1198                 unsigned char save_control, save_freq_select;
1199
1200                 /* Stolen from arch/i386/kernel/time.c, see there for
1201                  * credits and descriptive comments.
1202                  */
1203                 spin_lock_irqsave(&rtc_lock, flags);
1204                 save_control = CMOS_READ(RTC_CONTROL); /* tell the clock it's being set */
1205                 CMOS_WRITE((save_control|RTC_SET), RTC_CONTROL);
1206
1207                 save_freq_select = CMOS_READ(RTC_FREQ_SELECT); /* stop and reset prescaler */
1208                 CMOS_WRITE((save_freq_select|RTC_DIV_RESET2), RTC_FREQ_SELECT);
1209
1210                 chip_minutes = CMOS_READ(RTC_MINUTES);
1211                 if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD)
1212                         BCD_TO_BIN(chip_minutes);
1213                 real_seconds = nowtime % 60;
1214                 real_minutes = nowtime / 60;
1215                 if (((abs(real_minutes - chip_minutes) + 15)/30) & 1)
1216                         real_minutes += 30;
1217                 real_minutes %= 60;
1218
1219                 if (abs(real_minutes - chip_minutes) < 30) {
1220                         if (!(save_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
1221                                 BIN_TO_BCD(real_seconds);
1222                                 BIN_TO_BCD(real_minutes);
1223                         }
1224                         CMOS_WRITE(real_seconds,RTC_SECONDS);
1225                         CMOS_WRITE(real_minutes,RTC_MINUTES);
1226                 } else {
1227                         printk(KERN_WARNING
1228                                "set_rtc_mmss: can't update from %d to %d\n",
1229                                chip_minutes, real_minutes);
1230                         retval = -1;
1231                 }
1232
1233                 CMOS_WRITE(save_control, RTC_CONTROL);
1234                 CMOS_WRITE(save_freq_select, RTC_FREQ_SELECT);
1235                 spin_unlock_irqrestore(&rtc_lock, flags);
1236
1237                 return retval;
1238         }
1239 }
1240
1241 #define RTC_IS_OPEN             0x01    /* means /dev/rtc is in use     */
1242 static unsigned char mini_rtc_status;   /* bitmapped status byte.       */
1243
1244 /* months start at 0 now */
1245 static unsigned char days_in_mo[] =
1246 {31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31};
1247
1248 #define FEBRUARY        2
1249 #define STARTOFTIME     1970
1250 #define SECDAY          86400L
1251 #define SECYR           (SECDAY * 365)
1252 #define leapyear(year)          ((year) % 4 == 0 && \
1253                                  ((year) % 100 != 0 || (year) % 400 == 0))
1254 #define days_in_year(a)         (leapyear(a) ? 366 : 365)
1255 #define days_in_month(a)        (month_days[(a) - 1])
1256
1257 static int month_days[12] = {
1258         31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
1259 };
1260
1261 /*
1262  * This only works for the Gregorian calendar - i.e. after 1752 (in the UK)
1263  */
1264 static void GregorianDay(struct rtc_time * tm)
1265 {
1266         int leapsToDate;
1267         int lastYear;
1268         int day;
1269         int MonthOffset[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 };
1270
1271         lastYear = tm->tm_year - 1;
1272
1273         /*
1274          * Number of leap corrections to apply up to end of last year
1275          */
1276         leapsToDate = lastYear / 4 - lastYear / 100 + lastYear / 400;
1277
1278         /*
1279          * This year is a leap year if it is divisible by 4 except when it is
1280          * divisible by 100 unless it is divisible by 400
1281          *
1282          * e.g. 1904 was a leap year, 1900 was not, 1996 is, and 2000 was
1283          */
1284         day = tm->tm_mon > 2 && leapyear(tm->tm_year);
1285
1286         day += lastYear*365 + leapsToDate + MonthOffset[tm->tm_mon-1] +
1287                    tm->tm_mday;
1288
1289         tm->tm_wday = day % 7;
1290 }
1291
1292 static void to_tm(int tim, struct rtc_time *tm)
1293 {
1294         register int    i;
1295         register long   hms, day;
1296
1297         day = tim / SECDAY;
1298         hms = tim % SECDAY;
1299
1300         /* Hours, minutes, seconds are easy */
1301         tm->tm_hour = hms / 3600;
1302         tm->tm_min = (hms % 3600) / 60;
1303         tm->tm_sec = (hms % 3600) % 60;
1304
1305         /* Number of years in days */
1306         for (i = STARTOFTIME; day >= days_in_year(i); i++)
1307                 day -= days_in_year(i);
1308         tm->tm_year = i;
1309
1310         /* Number of months in days left */
1311         if (leapyear(tm->tm_year))
1312                 days_in_month(FEBRUARY) = 29;
1313         for (i = 1; day >= days_in_month(i); i++)
1314                 day -= days_in_month(i);
1315         days_in_month(FEBRUARY) = 28;
1316         tm->tm_mon = i;
1317
1318         /* Days are what is left over (+1) from all that. */
1319         tm->tm_mday = day + 1;
1320
1321         /*
1322          * Determine the day of week
1323          */
1324         GregorianDay(tm);
1325 }
1326
1327 /* Both Starfire and SUN4V give us seconds since Jan 1st, 1970,
1328  * aka Unix time.  So we have to convert to/from rtc_time.
1329  */
1330 static inline void mini_get_rtc_time(struct rtc_time *time)
1331 {
1332         unsigned long flags;
1333         u32 seconds;
1334
1335         spin_lock_irqsave(&rtc_lock, flags);
1336         seconds = 0;
1337         if (this_is_starfire)
1338                 seconds = starfire_get_time();
1339         else if (tlb_type == hypervisor)
1340                 seconds = hypervisor_get_time();
1341         spin_unlock_irqrestore(&rtc_lock, flags);
1342
1343         to_tm(seconds, time);
1344         time->tm_year -= 1900;
1345         time->tm_mon -= 1;
1346 }
1347
1348 static inline int mini_set_rtc_time(struct rtc_time *time)
1349 {
1350         u32 seconds = mktime(time->tm_year + 1900, time->tm_mon + 1,
1351                              time->tm_mday, time->tm_hour,
1352                              time->tm_min, time->tm_sec);
1353         unsigned long flags;
1354         int err;
1355
1356         spin_lock_irqsave(&rtc_lock, flags);
1357         err = -ENODEV;
1358         if (this_is_starfire)
1359                 err = starfire_set_time(seconds);
1360         else  if (tlb_type == hypervisor)
1361                 err = hypervisor_set_time(seconds);
1362         spin_unlock_irqrestore(&rtc_lock, flags);
1363
1364         return err;
1365 }
1366
1367 static int mini_rtc_ioctl(struct inode *inode, struct file *file,
1368                           unsigned int cmd, unsigned long arg)
1369 {
1370         struct rtc_time wtime;
1371         void __user *argp = (void __user *)arg;
1372
1373         switch (cmd) {
1374
1375         case RTC_PLL_GET:
1376                 return -EINVAL;
1377
1378         case RTC_PLL_SET:
1379                 return -EINVAL;
1380
1381         case RTC_UIE_OFF:       /* disable ints from RTC updates.       */
1382                 return 0;
1383
1384         case RTC_UIE_ON:        /* enable ints for RTC updates. */
1385                 return -EINVAL;
1386
1387         case RTC_RD_TIME:       /* Read the time/date from RTC  */
1388                 /* this doesn't get week-day, who cares */
1389                 memset(&wtime, 0, sizeof(wtime));
1390                 mini_get_rtc_time(&wtime);
1391
1392                 return copy_to_user(argp, &wtime, sizeof(wtime)) ? -EFAULT : 0;
1393
1394         case RTC_SET_TIME:      /* Set the RTC */
1395             {
1396                 int year;
1397                 unsigned char leap_yr;
1398
1399                 if (!capable(CAP_SYS_TIME))
1400                         return -EACCES;
1401
1402                 if (copy_from_user(&wtime, argp, sizeof(wtime)))
1403                         return -EFAULT;
1404
1405                 year = wtime.tm_year + 1900;
1406                 leap_yr = ((!(year % 4) && (year % 100)) ||
1407                            !(year % 400));
1408
1409                 if ((wtime.tm_mon < 0 || wtime.tm_mon > 11) || (wtime.tm_mday < 1))
1410                         return -EINVAL;
1411
1412                 if (wtime.tm_mday < 0 || wtime.tm_mday >
1413                     (days_in_mo[wtime.tm_mon] + ((wtime.tm_mon == 1) && leap_yr)))
1414                         return -EINVAL;
1415
1416                 if (wtime.tm_hour < 0 || wtime.tm_hour >= 24 ||
1417                     wtime.tm_min < 0 || wtime.tm_min >= 60 ||
1418                     wtime.tm_sec < 0 || wtime.tm_sec >= 60)
1419                         return -EINVAL;
1420
1421                 return mini_set_rtc_time(&wtime);
1422             }
1423         }
1424
1425         return -EINVAL;
1426 }
1427
1428 static int mini_rtc_open(struct inode *inode, struct file *file)
1429 {
1430         if (mini_rtc_status & RTC_IS_OPEN)
1431                 return -EBUSY;
1432
1433         mini_rtc_status |= RTC_IS_OPEN;
1434
1435         return 0;
1436 }
1437
1438 static int mini_rtc_release(struct inode *inode, struct file *file)
1439 {
1440         mini_rtc_status &= ~RTC_IS_OPEN;
1441         return 0;
1442 }
1443
1444
1445 static struct file_operations mini_rtc_fops = {
1446         .owner          = THIS_MODULE,
1447         .ioctl          = mini_rtc_ioctl,
1448         .open           = mini_rtc_open,
1449         .release        = mini_rtc_release,
1450 };
1451
1452 static struct miscdevice rtc_mini_dev =
1453 {
1454         .minor          = RTC_MINOR,
1455         .name           = "rtc",
1456         .fops           = &mini_rtc_fops,
1457 };
1458
1459 static int __init rtc_mini_init(void)
1460 {
1461         int retval;
1462
1463         if (tlb_type != hypervisor && !this_is_starfire)
1464                 return -ENODEV;
1465
1466         printk(KERN_INFO "Mini RTC Driver\n");
1467
1468         retval = misc_register(&rtc_mini_dev);
1469         if (retval < 0)
1470                 return retval;
1471
1472         return 0;
1473 }
1474
1475 static void __exit rtc_mini_exit(void)
1476 {
1477         misc_deregister(&rtc_mini_dev);
1478 }
1479
1480
1481 module_init(rtc_mini_init);
1482 module_exit(rtc_mini_exit);