arch/sparc/kernel/time_64.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* time.c: UltraSparc timer and TOD clock support.
   3  *
   4  * Copyright (C) 1997, 2008 David S. Miller (davem@davemloft.net)
   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/errno.h>
  13 #include <linux/export.h>
  14 #include <linux/sched.h>
  15 #include <linux/kernel.h>
  16 #include <linux/param.h>
  17 #include <linux/string.h>
  18 #include <linux/mm.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/time.h>
  21 #include <linux/timex.h>
  22 #include <linux/init.h>
  23 #include <linux/ioport.h>
  24 #include <linux/mc146818rtc.h>
  25 #include <linux/delay.h>
  26 #include <linux/profile.h>
  27 #include <linux/bcd.h>
  28 #include <linux/jiffies.h>
  29 #include <linux/cpufreq.h>
  30 #include <linux/percpu.h>
  31 #include <linux/rtc/m48t59.h>
  32 #include <linux/kernel_stat.h>
  33 #include <linux/clockchips.h>
  34 #include <linux/clocksource.h>
  35 #include <linux/platform_device.h>
  36 #include <linux/ftrace.h>
  37
  38 #include <asm/oplib.h>
  39 #include <asm/timer.h>
  40 #include <asm/irq.h>
  41 #include <asm/io.h>
  42 #include <asm/prom.h>
  43 #include <asm/starfire.h>
  44 #include <asm/smp.h>
  45 #include <asm/sections.h>
  46 #include <asm/cpudata.h>
  47 #include <linux/uaccess.h>
  48 #include <asm/irq_regs.h>
  49 #include <asm/cacheflush.h>
  50
  51 #include "entry.h"
  52 #include "kernel.h"
  53
  54 DEFINE_SPINLOCK(rtc_lock);
  55
  56 unsigned int __read_mostly vdso_fix_stick;
  57
  58 #ifdef CONFIG_SMP
  59 unsigned long profile_pc(struct pt_regs *regs)
  60 {
  61         unsigned long pc = instruction_pointer(regs);
  62
  63         if (in_lock_functions(pc))
  64                 return regs->u_regs[UREG_RETPC];
  65         return pc;
  66 }
  67 EXPORT_SYMBOL(profile_pc);
  68 #endif
  69
  70 static void tick_disable_protection(void)
  71 {
  72         /* Set things up so user can access tick register for profiling
  73          * purposes.  Also workaround BB_ERRATA_1 by doing a dummy
  74          * read back of %tick after writing it.
  75          */
  76         __asm__ __volatile__(
  77         "       ba,pt   %%xcc, 1f\n"
  78         "        nop\n"
  79         "       .align  64\n"
  80         "1:     rd      %%tick, %%g2\n"
  81         "       add     %%g2, 6, %%g2\n"
  82         "       andn    %%g2, %0, %%g2\n"
  83         "       wrpr    %%g2, 0, %%tick\n"
  84         "       rdpr    %%tick, %%g0"
  85         : /* no outputs */
  86         : "r" (TICK_PRIV_BIT)
  87         : "g2");
  88 }
  89
  90 static void tick_disable_irq(void)
  91 {
  92         __asm__ __volatile__(
  93         "       ba,pt   %%xcc, 1f\n"
  94         "        nop\n"
  95         "       .align  64\n"
  96         "1:     wr      %0, 0x0, %%tick_cmpr\n"
  97         "       rd      %%tick_cmpr, %%g0"
  98         : /* no outputs */
  99         : "r" (TICKCMP_IRQ_BIT));
 100 }
 101
 102 static void tick_init_tick(void)
 103 {
 104         tick_disable_protection();
 105         tick_disable_irq();
 106 }
 107
 108 static unsigned long long tick_get_tick(void)
 109 {
 110         unsigned long ret;
 111
 112         __asm__ __volatile__("rd        %%tick, %0\n\t"
 113                              "mov       %0, %0"
 114                              : "=r" (ret));
 115
 116         return ret & ~TICK_PRIV_BIT;
 117 }
 118
 119 static int tick_add_compare(unsigned long adj)
 120 {
 121         unsigned long orig_tick, new_tick, new_compare;
 122
 123         __asm__ __volatile__("rd        %%tick, %0"
 124                              : "=r" (orig_tick));
 125
 126         orig_tick &= ~TICKCMP_IRQ_BIT;
 127
 128         /* Workaround for Spitfire Errata (#54 I think??), I discovered
 129          * this via Sun BugID 4008234, mentioned in Solaris-2.5.1 patch
 130          * number 103640.
 131          *
 132          * On Blackbird writes to %tick_cmpr can fail, the
 133          * workaround seems to be to execute the wr instruction
 134          * at the start of an I-cache line, and perform a dummy
 135          * read back from %tick_cmpr right after writing to it. -DaveM
 136          */
 137         __asm__ __volatile__("ba,pt     %%xcc, 1f\n\t"
 138                              " add      %1, %2, %0\n\t"
 139                              ".align    64\n"
 140                              "1:\n\t"
 141                              "wr        %0, 0, %%tick_cmpr\n\t"
 142                              "rd        %%tick_cmpr, %%g0\n\t"
 143                              : "=r" (new_compare)
 144                              : "r" (orig_tick), "r" (adj));
 145
 146         __asm__ __volatile__("rd        %%tick, %0"
 147                              : "=r" (new_tick));
 148         new_tick &= ~TICKCMP_IRQ_BIT;
 149
 150         return ((long)(new_tick - (orig_tick+adj))) > 0L;
 151 }
 152
 153 static unsigned long tick_add_tick(unsigned long adj)
 154 {
 155         unsigned long new_tick;
 156
 157         /* Also need to handle Blackbird bug here too. */
 158         __asm__ __volatile__("rd        %%tick, %0\n\t"
 159                              "add       %0, %1, %0\n\t"
 160                              "wrpr      %0, 0, %%tick\n\t"
 161                              : "=&r" (new_tick)
 162                              : "r" (adj));
 163
 164         return new_tick;
 165 }
 166
 167 /* Searches for cpu clock frequency with given cpuid in OpenBoot tree */
 168 static unsigned long cpuid_to_freq(phandle node, int cpuid)
 169 {
 170         bool is_cpu_node = false;
 171         unsigned long freq = 0;
 172         char type[128];
 173
 174         if (!node)
 175                 return freq;
 176
 177         if (prom_getproperty(node, "device_type", type, sizeof(type)) != -1)
 178                 is_cpu_node = (strcmp(type, "cpu") == 0);
 179
 180         /* try upa-portid then cpuid to get cpuid, see prom_64.c */
 181         if (is_cpu_node && (prom_getint(node, "upa-portid") == cpuid ||
 182                             prom_getint(node, "cpuid") == cpuid))
 183                 freq = prom_getintdefault(node, "clock-frequency", 0);
 184         if (!freq)
 185                 freq = cpuid_to_freq(prom_getchild(node), cpuid);
 186         if (!freq)
 187                 freq = cpuid_to_freq(prom_getsibling(node), cpuid);
 188
 189         return freq;
 190 }
 191
 192 static unsigned long tick_get_frequency(void)
 193 {
 194         return cpuid_to_freq(prom_root_node, hard_smp_processor_id());
 195 }
 196
 197 static struct sparc64_tick_ops tick_operations __cacheline_aligned = {
 198         .name           =       "tick",
 199         .init_tick      =       tick_init_tick,
 200         .disable_irq    =       tick_disable_irq,
 201         .get_tick       =       tick_get_tick,
 202         .add_tick       =       tick_add_tick,
 203         .add_compare    =       tick_add_compare,
 204         .get_frequency  =       tick_get_frequency,
 205         .softint_mask   =       1UL << 0,
 206 };
 207
 208 struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
 209 EXPORT_SYMBOL(tick_ops);
 210
 211 static void stick_disable_irq(void)
 212 {
 213         __asm__ __volatile__(
 214         "wr     %0, 0x0, %%asr25"
 215         : /* no outputs */
 216         : "r" (TICKCMP_IRQ_BIT));
 217 }
 218
 219 static void stick_init_tick(void)
 220 {
 221         /* Writes to the %tick and %stick register are not
 222          * allowed on sun4v.  The Hypervisor controls that
 223          * bit, per-strand.
 224          */
 225         if (tlb_type != hypervisor) {
 226                 tick_disable_protection();
 227                 tick_disable_irq();
 228
 229                 /* Let the user get at STICK too. */
 230                 __asm__ __volatile__(
 231                 "       rd      %%asr24, %%g2\n"
 232                 "       andn    %%g2, %0, %%g2\n"
 233                 "       wr      %%g2, 0, %%asr24"
 234                 : /* no outputs */
 235                 : "r" (TICK_PRIV_BIT)
 236                 : "g1", "g2");
 237         }
 238
 239         stick_disable_irq();
 240 }
 241
 242 static unsigned long long stick_get_tick(void)
 243 {
 244         unsigned long ret;
 245
 246         __asm__ __volatile__("rd        %%asr24, %0"
 247                              : "=r" (ret));
 248
 249         return ret & ~TICK_PRIV_BIT;
 250 }
 251
 252 static unsigned long stick_add_tick(unsigned long adj)
 253 {
 254         unsigned long new_tick;
 255
 256         __asm__ __volatile__("rd        %%asr24, %0\n\t"
 257                              "add       %0, %1, %0\n\t"
 258                              "wr        %0, 0, %%asr24\n\t"
 259                              : "=&r" (new_tick)
 260                              : "r" (adj));
 261
 262         return new_tick;
 263 }
 264
 265 static int stick_add_compare(unsigned long adj)
 266 {
 267         unsigned long orig_tick, new_tick;
 268
 269         __asm__ __volatile__("rd        %%asr24, %0"
 270                              : "=r" (orig_tick));
 271         orig_tick &= ~TICKCMP_IRQ_BIT;
 272
 273         __asm__ __volatile__("wr        %0, 0, %%asr25"
 274                              : /* no outputs */
 275                              : "r" (orig_tick + adj));
 276
 277         __asm__ __volatile__("rd        %%asr24, %0"
 278                              : "=r" (new_tick));
 279         new_tick &= ~TICKCMP_IRQ_BIT;
 280
 281         return ((long)(new_tick - (orig_tick+adj))) > 0L;
 282 }
 283
 284 static unsigned long stick_get_frequency(void)
 285 {
 286         return prom_getintdefault(prom_root_node, "stick-frequency", 0);
 287 }
 288
 289 static struct sparc64_tick_ops stick_operations __read_mostly = {
 290         .name           =       "stick",
 291         .init_tick      =       stick_init_tick,
 292         .disable_irq    =       stick_disable_irq,
 293         .get_tick       =       stick_get_tick,
 294         .add_tick       =       stick_add_tick,
 295         .add_compare    =       stick_add_compare,
 296         .get_frequency  =       stick_get_frequency,
 297         .softint_mask   =       1UL << 16,
 298 };
 299
 300 /* On Hummingbird the STICK/STICK_CMPR register is implemented
 301  * in I/O space.  There are two 64-bit registers each, the
 302  * first holds the low 32-bits of the value and the second holds
 303  * the high 32-bits.
 304  *
 305  * Since STICK is constantly updating, we have to access it carefully.
 306  *
 307  * The sequence we use to read is:
 308  * 1) read high
 309  * 2) read low
 310  * 3) read high again, if it rolled re-read both low and high again.
 311  *
 312  * Writing STICK safely is also tricky:
 313  * 1) write low to zero
 314  * 2) write high
 315  * 3) write low
 316  */
 317 static unsigned long __hbird_read_stick(void)
 318 {
 319         unsigned long ret, tmp1, tmp2, tmp3;
 320         unsigned long addr = HBIRD_STICK_ADDR+8;
 321
 322         __asm__ __volatile__("ldxa      [%1] %5, %2\n"
 323                              "1:\n\t"
 324                              "sub       %1, 0x8, %1\n\t"
 325                              "ldxa      [%1] %5, %3\n\t"
 326                              "add       %1, 0x8, %1\n\t"
 327                              "ldxa      [%1] %5, %4\n\t"
 328                              "cmp       %4, %2\n\t"
 329                              "bne,a,pn  %%xcc, 1b\n\t"
 330                              " mov      %4, %2\n\t"
 331                              "sllx      %4, 32, %4\n\t"
 332                              "or        %3, %4, %0\n\t"
 333                              : "=&r" (ret), "=&r" (addr),
 334                                "=&r" (tmp1), "=&r" (tmp2), "=&r" (tmp3)
 335                              : "i" (ASI_PHYS_BYPASS_EC_E), "1" (addr));
 336
 337         return ret;
 338 }
 339
 340 static void __hbird_write_stick(unsigned long val)
 341 {
 342         unsigned long low = (val & 0xffffffffUL);
 343         unsigned long high = (val >> 32UL);
 344         unsigned long addr = HBIRD_STICK_ADDR;
 345
 346         __asm__ __volatile__("stxa      %%g0, [%0] %4\n\t"
 347                              "add       %0, 0x8, %0\n\t"
 348                              "stxa      %3, [%0] %4\n\t"
 349                              "sub       %0, 0x8, %0\n\t"
 350                              "stxa      %2, [%0] %4"
 351                              : "=&r" (addr)
 352                              : "0" (addr), "r" (low), "r" (high),
 353                                "i" (ASI_PHYS_BYPASS_EC_E));
 354 }
 355
 356 static void __hbird_write_compare(unsigned long val)
 357 {
 358         unsigned long low = (val & 0xffffffffUL);
 359         unsigned long high = (val >> 32UL);
 360         unsigned long addr = HBIRD_STICKCMP_ADDR + 0x8UL;
 361
 362         __asm__ __volatile__("stxa      %3, [%0] %4\n\t"
 363                              "sub       %0, 0x8, %0\n\t"
 364                              "stxa      %2, [%0] %4"
 365                              : "=&r" (addr)
 366                              : "0" (addr), "r" (low), "r" (high),
 367                                "i" (ASI_PHYS_BYPASS_EC_E));
 368 }
 369
 370 static void hbtick_disable_irq(void)
 371 {
 372         __hbird_write_compare(TICKCMP_IRQ_BIT);
 373 }
 374
 375 static void hbtick_init_tick(void)
 376 {
 377         tick_disable_protection();
 378
 379         /* XXX This seems to be necessary to 'jumpstart' Hummingbird
 380          * XXX into actually sending STICK interrupts.  I think because
 381          * XXX of how we store %tick_cmpr in head.S this somehow resets the
 382          * XXX {TICK + STICK} interrupt mux.  -DaveM
 383          */
 384         __hbird_write_stick(__hbird_read_stick());
 385
 386         hbtick_disable_irq();
 387 }
 388
 389 static unsigned long long hbtick_get_tick(void)
 390 {
 391         return __hbird_read_stick() & ~TICK_PRIV_BIT;
 392 }
 393
 394 static unsigned long hbtick_add_tick(unsigned long adj)
 395 {
 396         unsigned long val;
 397
 398         val = __hbird_read_stick() + adj;
 399         __hbird_write_stick(val);
 400
 401         return val;
 402 }
 403
 404 static int hbtick_add_compare(unsigned long adj)
 405 {
 406         unsigned long val = __hbird_read_stick();
 407         unsigned long val2;
 408
 409         val &= ~TICKCMP_IRQ_BIT;
 410         val += adj;
 411         __hbird_write_compare(val);
 412
 413         val2 = __hbird_read_stick() & ~TICKCMP_IRQ_BIT;
 414
 415         return ((long)(val2 - val)) > 0L;
 416 }
 417
 418 static unsigned long hbtick_get_frequency(void)
 419 {
 420         return prom_getintdefault(prom_root_node, "stick-frequency", 0);
 421 }
 422
 423 static struct sparc64_tick_ops hbtick_operations __read_mostly = {
 424         .name           =       "hbtick",
 425         .init_tick      =       hbtick_init_tick,
 426         .disable_irq    =       hbtick_disable_irq,
 427         .get_tick       =       hbtick_get_tick,
 428         .add_tick       =       hbtick_add_tick,
 429         .add_compare    =       hbtick_add_compare,
 430         .get_frequency  =       hbtick_get_frequency,
 431         .softint_mask   =       1UL << 0,
 432 };
 433
 434 unsigned long cmos_regs;
 435 EXPORT_SYMBOL(cmos_regs);
 436
 437 static struct resource rtc_cmos_resource;
 438
 439 static struct platform_device rtc_cmos_device = {
 440         .name           = "rtc_cmos",
 441         .id             = -1,
 442         .resource       = &rtc_cmos_resource,
 443         .num_resources  = 1,
 444 };
 445
 446 static int rtc_probe(struct platform_device *op)
 447 {
 448         struct resource *r;
 449
 450         printk(KERN_INFO "%s: RTC regs at 0x%llx\n",
 451                op->dev.of_node->full_name, op->resource[0].start);
 452
 453         /* The CMOS RTC driver only accepts IORESOURCE_IO, so cons
 454          * up a fake resource so that the probe works for all cases.
 455          * When the RTC is behind an ISA bus it will have IORESOURCE_IO
 456          * already, whereas when it's behind EBUS is will be IORESOURCE_MEM.
 457          */
 458
 459         r = &rtc_cmos_resource;
 460         r->flags = IORESOURCE_IO;
 461         r->name = op->resource[0].name;
 462         r->start = op->resource[0].start;
 463         r->end = op->resource[0].end;
 464
 465         cmos_regs = op->resource[0].start;
 466         return platform_device_register(&rtc_cmos_device);
 467 }
 468
 469 static const struct of_device_id rtc_match[] = {
 470         {
 471                 .name = "rtc",
 472                 .compatible = "m5819",
 473         },
 474         {
 475                 .name = "rtc",
 476                 .compatible = "isa-m5819p",
 477         },
 478         {
 479                 .name = "rtc",
 480                 .compatible = "isa-m5823p",
 481         },
 482         {
 483                 .name = "rtc",
 484                 .compatible = "ds1287",
 485         },
 486         {},
 487 };
 488
 489 static struct platform_driver rtc_driver = {
 490         .probe          = rtc_probe,
 491         .driver = {
 492                 .name = "rtc",
 493                 .of_match_table = rtc_match,
 494         },
 495 };
 496
 497 static struct platform_device rtc_bq4802_device = {
 498         .name           = "rtc-bq4802",
 499         .id             = -1,
 500         .num_resources  = 1,
 501 };
 502
 503 static int bq4802_probe(struct platform_device *op)
 504 {
 505
 506         printk(KERN_INFO "%s: BQ4802 regs at 0x%llx\n",
 507                op->dev.of_node->full_name, op->resource[0].start);
 508
 509         rtc_bq4802_device.resource = &op->resource[0];
 510         return platform_device_register(&rtc_bq4802_device);
 511 }
 512
 513 static const struct of_device_id bq4802_match[] = {
 514         {
 515                 .name = "rtc",
 516                 .compatible = "bq4802",
 517         },
 518         {},
 519 };
 520
 521 static struct platform_driver bq4802_driver = {
 522         .probe          = bq4802_probe,
 523         .driver = {
 524                 .name = "bq4802",
 525                 .of_match_table = bq4802_match,
 526         },
 527 };
 528
 529 static unsigned char mostek_read_byte(struct device *dev, u32 ofs)
 530 {
 531         struct platform_device *pdev = to_platform_device(dev);
 532         void __iomem *regs = (void __iomem *) pdev->resource[0].start;
 533
 534         return readb(regs + ofs);
 535 }
 536
 537 static void mostek_write_byte(struct device *dev, u32 ofs, u8 val)
 538 {
 539         struct platform_device *pdev = to_platform_device(dev);
 540         void __iomem *regs = (void __iomem *) pdev->resource[0].start;
 541
 542         writeb(val, regs + ofs);
 543 }
 544
 545 static struct m48t59_plat_data m48t59_data = {
 546         .read_byte      = mostek_read_byte,
 547         .write_byte     = mostek_write_byte,
 548 };
 549
 550 static struct platform_device m48t59_rtc = {
 551         .name           = "rtc-m48t59",
 552         .id             = 0,
 553         .num_resources  = 1,
 554         .dev    = {
 555                 .platform_data = &m48t59_data,
 556         },
 557 };
 558
 559 static int mostek_probe(struct platform_device *op)
 560 {
 561         struct device_node *dp = op->dev.of_node;
 562
 563         /* On an Enterprise system there can be multiple mostek clocks.
 564          * We should only match the one that is on the central FHC bus.
 565          */
 566         if (!strcmp(dp->parent->name, "fhc") &&
 567             strcmp(dp->parent->parent->name, "central") != 0)
 568                 return -ENODEV;
 569
 570         printk(KERN_INFO "%s: Mostek regs at 0x%llx\n",
 571                dp->full_name, op->resource[0].start);
 572
 573         m48t59_rtc.resource = &op->resource[0];
 574         return platform_device_register(&m48t59_rtc);
 575 }
 576
 577 static const struct of_device_id mostek_match[] = {
 578         {
 579                 .name = "eeprom",
 580         },
 581         {},
 582 };
 583
 584 static struct platform_driver mostek_driver = {
 585         .probe          = mostek_probe,
 586         .driver = {
 587                 .name = "mostek",
 588                 .of_match_table = mostek_match,
 589         },
 590 };
 591
 592 static struct platform_device rtc_sun4v_device = {
 593         .name           = "rtc-sun4v",
 594         .id             = -1,
 595 };
 596
 597 static struct platform_device rtc_starfire_device = {
 598         .name           = "rtc-starfire",
 599         .id             = -1,
 600 };
 601
 602 static int __init clock_init(void)
 603 {
 604         if (this_is_starfire)
 605                 return platform_device_register(&rtc_starfire_device);
 606
 607         if (tlb_type == hypervisor)
 608                 return platform_device_register(&rtc_sun4v_device);
 609
 610         (void) platform_driver_register(&rtc_driver);
 611         (void) platform_driver_register(&mostek_driver);
 612         (void) platform_driver_register(&bq4802_driver);
 613
 614         return 0;
 615 }
 616
 617 /* Must be after subsys_initcall() so that busses are probed.  Must
 618  * be before device_initcall() because things like the RTC driver
 619  * need to see the clock registers.
 620  */
 621 fs_initcall(clock_init);
 622
 623 /* Return true if this is Hummingbird, aka Ultra-IIe */
 624 static bool is_hummingbird(void)
 625 {
 626         unsigned long ver, manuf, impl;
 627
 628         __asm__ __volatile__ ("rdpr %%ver, %0"
 629                               : "=&r" (ver));
 630         manuf = ((ver >> 48) & 0xffff);
 631         impl = ((ver >> 32) & 0xffff);
 632
 633         return (manuf == 0x17 && impl == 0x13);
 634 }
 635
 636 struct freq_table {
 637         unsigned long clock_tick_ref;
 638         unsigned int ref_freq;
 639 };
 640 static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
 641
 642 unsigned long sparc64_get_clock_tick(unsigned int cpu)
 643 {
 644         struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
 645
 646         if (ft->clock_tick_ref)
 647                 return ft->clock_tick_ref;
 648         return cpu_data(cpu).clock_tick;
 649 }
 650 EXPORT_SYMBOL(sparc64_get_clock_tick);
 651
 652 #ifdef CONFIG_CPU_FREQ
 653
 654 static int sparc64_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
 655                                     void *data)
 656 {
 657         struct cpufreq_freqs *freq = data;
 658         unsigned int cpu = freq->cpu;
 659         struct freq_table *ft = &per_cpu(sparc64_freq_table, cpu);
 660
 661         if (!ft->ref_freq) {
 662                 ft->ref_freq = freq->old;
 663                 ft->clock_tick_ref = cpu_data(cpu).clock_tick;
 664         }
 665         if ((val == CPUFREQ_PRECHANGE  && freq->old < freq->new) ||
 666             (val == CPUFREQ_POSTCHANGE && freq->old > freq->new)) {
 667                 cpu_data(cpu).clock_tick =
 668                         cpufreq_scale(ft->clock_tick_ref,
 669                                       ft->ref_freq,
 670                                       freq->new);
 671         }
 672
 673         return 0;
 674 }
 675
 676 static struct notifier_block sparc64_cpufreq_notifier_block = {
 677         .notifier_call  = sparc64_cpufreq_notifier
 678 };
 679
 680 static int __init register_sparc64_cpufreq_notifier(void)
 681 {
 682
 683         cpufreq_register_notifier(&sparc64_cpufreq_notifier_block,
 684                                   CPUFREQ_TRANSITION_NOTIFIER);
 685         return 0;
 686 }
 687
 688 core_initcall(register_sparc64_cpufreq_notifier);
 689
 690 #endif /* CONFIG_CPU_FREQ */
 691
 692 static int sparc64_next_event(unsigned long delta,
 693                               struct clock_event_device *evt)
 694 {
 695         return tick_operations.add_compare(delta) ? -ETIME : 0;
 696 }
 697
 698 static int sparc64_timer_shutdown(struct clock_event_device *evt)
 699 {
 700         tick_operations.disable_irq();
 701         return 0;
 702 }
 703
 704 static struct clock_event_device sparc64_clockevent = {
 705         .features               = CLOCK_EVT_FEAT_ONESHOT,
 706         .set_state_shutdown     = sparc64_timer_shutdown,
 707         .set_next_event         = sparc64_next_event,
 708         .rating                 = 100,
 709         .shift                  = 30,
 710         .irq                    = -1,
 711 };
 712 static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);
 713
 714 void __irq_entry timer_interrupt(int irq, struct pt_regs *regs)
 715 {
 716         struct pt_regs *old_regs = set_irq_regs(regs);
 717         unsigned long tick_mask = tick_operations.softint_mask;
 718         int cpu = smp_processor_id();
 719         struct clock_event_device *evt = &per_cpu(sparc64_events, cpu);
 720
 721         clear_softint(tick_mask);
 722
 723         irq_enter();
 724
 725         local_cpu_data().irq0_irqs++;
 726         kstat_incr_irq_this_cpu(0);
 727
 728         if (unlikely(!evt->event_handler)) {
 729                 printk(KERN_WARNING
 730                        "Spurious SPARC64 timer interrupt on cpu %d\n", cpu);
 731         } else
 732                 evt->event_handler(evt);
 733
 734         irq_exit();
 735
 736         set_irq_regs(old_regs);
 737 }
 738
 739 void setup_sparc64_timer(void)
 740 {
 741         struct clock_event_device *sevt;
 742         unsigned long pstate;
 743
 744         /* Guarantee that the following sequences execute
 745          * uninterrupted.
 746          */
 747         __asm__ __volatile__("rdpr      %%pstate, %0\n\t"
 748                              "wrpr      %0, %1, %%pstate"
 749                              : "=r" (pstate)
 750                              : "i" (PSTATE_IE));
 751
 752         tick_operations.init_tick();
 753
 754         /* Restore PSTATE_IE. */
 755         __asm__ __volatile__("wrpr      %0, 0x0, %%pstate"
 756                              : /* no outputs */
 757                              : "r" (pstate));
 758
 759         sevt = this_cpu_ptr(&sparc64_events);
 760
 761         memcpy(sevt, &sparc64_clockevent, sizeof(*sevt));
 762         sevt->cpumask = cpumask_of(smp_processor_id());
 763
 764         clockevents_register_device(sevt);
 765 }
 766
 767 #define SPARC64_NSEC_PER_CYC_SHIFT      10UL
 768
 769 static struct clocksource clocksource_tick = {
 770         .rating         = 100,
 771         .mask           = CLOCKSOURCE_MASK(64),
 772         .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
 773 };
 774
 775 static unsigned long tb_ticks_per_usec __read_mostly;
 776
 777 void __delay(unsigned long loops)
 778 {
 779         unsigned long bclock = get_tick();
 780
 781         while ((get_tick() - bclock) < loops)
 782                 ;
 783 }
 784 EXPORT_SYMBOL(__delay);
 785
 786 void udelay(unsigned long usecs)
 787 {
 788         __delay(tb_ticks_per_usec * usecs);
 789 }
 790 EXPORT_SYMBOL(udelay);
 791
 792 static u64 clocksource_tick_read(struct clocksource *cs)
 793 {
 794         return get_tick();
 795 }
 796
 797 static void __init get_tick_patch(void)
 798 {
 799         unsigned int *addr, *instr, i;
 800         struct get_tick_patch *p;
 801
 802         if (tlb_type == spitfire && is_hummingbird())
 803                 return;
 804
 805         for (p = &__get_tick_patch; p < &__get_tick_patch_end; p++) {
 806                 instr = (tlb_type == spitfire) ? p->tick : p->stick;
 807                 addr = (unsigned int *)(unsigned long)p->addr;
 808                 for (i = 0; i < GET_TICK_NINSTR; i++) {
 809                         addr[i] = instr[i];
 810                         /* ensure that address is modified before flush */
 811                         wmb();
 812                         flushi(&addr[i]);
 813                 }
 814         }
 815 }
 816
 817 static void init_tick_ops(struct sparc64_tick_ops *ops)
 818 {
 819         unsigned long freq, quotient, tick;
 820
 821         freq = ops->get_frequency();
 822         quotient = clocksource_hz2mult(freq, SPARC64_NSEC_PER_CYC_SHIFT);
 823         tick = ops->get_tick();
 824
 825         ops->offset = (tick * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT;
 826         ops->ticks_per_nsec_quotient = quotient;
 827         ops->frequency = freq;
 828         tick_operations = *ops;
 829         get_tick_patch();
 830 }
 831
 832 void __init time_init_early(void)
 833 {
 834         if (tlb_type == spitfire) {
 835                 if (is_hummingbird()) {
 836                         init_tick_ops(&hbtick_operations);
 837                         clocksource_tick.archdata.vclock_mode = VCLOCK_NONE;
 838                 } else {
 839                         init_tick_ops(&tick_operations);
 840                         clocksource_tick.archdata.vclock_mode = VCLOCK_TICK;
 841                         vdso_fix_stick = 1;
 842                 }
 843         } else {
 844                 init_tick_ops(&stick_operations);
 845                 clocksource_tick.archdata.vclock_mode = VCLOCK_STICK;
 846         }
 847 }
 848
 849 void __init time_init(void)
 850 {
 851         unsigned long freq;
 852
 853         freq = tick_operations.frequency;
 854         tb_ticks_per_usec = freq / USEC_PER_SEC;
 855
 856         clocksource_tick.name = tick_operations.name;
 857         clocksource_tick.read = clocksource_tick_read;
 858
 859         clocksource_register_hz(&clocksource_tick, freq);
 860         printk("clocksource: mult[%x] shift[%d]\n",
 861                clocksource_tick.mult, clocksource_tick.shift);
 862
 863         sparc64_clockevent.name = tick_operations.name;
 864         clockevents_calc_mult_shift(&sparc64_clockevent, freq, 4);
 865
 866         sparc64_clockevent.max_delta_ns =
 867                 clockevent_delta2ns(0x7fffffffffffffffUL, &sparc64_clockevent);
 868         sparc64_clockevent.max_delta_ticks = 0x7fffffffffffffffUL;
 869         sparc64_clockevent.min_delta_ns =
 870                 clockevent_delta2ns(0xF, &sparc64_clockevent);
 871         sparc64_clockevent.min_delta_ticks = 0xF;
 872
 873         printk("clockevent: mult[%x] shift[%d]\n",
 874                sparc64_clockevent.mult, sparc64_clockevent.shift);
 875
 876         setup_sparc64_timer();
 877 }
 878
 879 unsigned long long sched_clock(void)
 880 {
 881         unsigned long quotient = tick_operations.ticks_per_nsec_quotient;
 882         unsigned long offset = tick_operations.offset;
 883
 884         /* Use barrier so the compiler emits the loads first and overlaps load
 885          * latency with reading tick, because reading %tick/%stick is a
 886          * post-sync instruction that will flush and restart subsequent
 887          * instructions after it commits.
 888          */
 889         barrier();
 890
 891         return ((get_tick() * quotient) >> SPARC64_NSEC_PER_CYC_SHIFT) - offset;
 892 }
 893
 894 int read_current_timer(unsigned long *timer_val)
 895 {
 896         *timer_val = get_tick();
 897         return 0;
 898 }