linux/arch/sparc/kernel/time_64.c
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   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
  54DEFINE_SPINLOCK(rtc_lock);
  55
  56unsigned int __read_mostly vdso_fix_stick;
  57
  58#ifdef CONFIG_SMP
  59unsigned 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}
  67EXPORT_SYMBOL(profile_pc);
  68#endif
  69
  70static 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
  90static 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
 102static void tick_init_tick(void)
 103{
 104        tick_disable_protection();
 105        tick_disable_irq();
 106}
 107
 108static 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
 119static 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
 153static 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 */
 168static 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
 192static unsigned long tick_get_frequency(void)
 193{
 194        return cpuid_to_freq(prom_root_node, hard_smp_processor_id());
 195}
 196
 197static 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
 208struct sparc64_tick_ops *tick_ops __read_mostly = &tick_operations;
 209EXPORT_SYMBOL(tick_ops);
 210
 211static void stick_disable_irq(void)
 212{
 213        __asm__ __volatile__(
 214        "wr     %0, 0x0, %%asr25"
 215        : /* no outputs */
 216        : "r" (TICKCMP_IRQ_BIT));
 217}
 218
 219static 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
 242static 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
 252static 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
 265static 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
 284static unsigned long stick_get_frequency(void)
 285{
 286        return prom_getintdefault(prom_root_node, "stick-frequency", 0);
 287}
 288
 289static 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 */
 317static 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
 340static 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
 356static 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
 370static void hbtick_disable_irq(void)
 371{
 372        __hbird_write_compare(TICKCMP_IRQ_BIT);
 373}
 374
 375static 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
 389static unsigned long long hbtick_get_tick(void)
 390{
 391        return __hbird_read_stick() & ~TICK_PRIV_BIT;
 392}
 393
 394static 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
 404static 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
 418static unsigned long hbtick_get_frequency(void)
 419{
 420        return prom_getintdefault(prom_root_node, "stick-frequency", 0);
 421}
 422
 423static 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
 434unsigned long cmos_regs;
 435EXPORT_SYMBOL(cmos_regs);
 436
 437static struct resource rtc_cmos_resource;
 438
 439static struct platform_device rtc_cmos_device = {
 440        .name           = "rtc_cmos",
 441        .id             = -1,
 442        .resource       = &rtc_cmos_resource,
 443        .num_resources  = 1,
 444};
 445
 446static 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
 469static 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
 489static struct platform_driver rtc_driver = {
 490        .probe          = rtc_probe,
 491        .driver = {
 492                .name = "rtc",
 493                .of_match_table = rtc_match,
 494        },
 495};
 496
 497static struct platform_device rtc_bq4802_device = {
 498        .name           = "rtc-bq4802",
 499        .id             = -1,
 500        .num_resources  = 1,
 501};
 502
 503static 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
 513static const struct of_device_id bq4802_match[] = {
 514        {
 515                .name = "rtc",
 516                .compatible = "bq4802",
 517        },
 518        {},
 519};
 520
 521static struct platform_driver bq4802_driver = {
 522        .probe          = bq4802_probe,
 523        .driver = {
 524                .name = "bq4802",
 525                .of_match_table = bq4802_match,
 526        },
 527};
 528
 529static 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
 537static 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
 545static struct m48t59_plat_data m48t59_data = {
 546        .read_byte      = mostek_read_byte,
 547        .write_byte     = mostek_write_byte,
 548};
 549
 550static 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
 559static 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
 577static const struct of_device_id mostek_match[] = {
 578        {
 579                .name = "eeprom",
 580        },
 581        {},
 582};
 583
 584static struct platform_driver mostek_driver = {
 585        .probe          = mostek_probe,
 586        .driver = {
 587                .name = "mostek",
 588                .of_match_table = mostek_match,
 589        },
 590};
 591
 592static struct platform_device rtc_sun4v_device = {
 593        .name           = "rtc-sun4v",
 594        .id             = -1,
 595};
 596
 597static struct platform_device rtc_starfire_device = {
 598        .name           = "rtc-starfire",
 599        .id             = -1,
 600};
 601
 602static 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 */
 621fs_initcall(clock_init);
 622
 623/* Return true if this is Hummingbird, aka Ultra-IIe */
 624static 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
 636struct freq_table {
 637        unsigned long clock_tick_ref;
 638        unsigned int ref_freq;
 639};
 640static DEFINE_PER_CPU(struct freq_table, sparc64_freq_table) = { 0, 0 };
 641
 642unsigned 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}
 650EXPORT_SYMBOL(sparc64_get_clock_tick);
 651
 652#ifdef CONFIG_CPU_FREQ
 653
 654static 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
 676static struct notifier_block sparc64_cpufreq_notifier_block = {
 677        .notifier_call  = sparc64_cpufreq_notifier
 678};
 679
 680static 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
 688core_initcall(register_sparc64_cpufreq_notifier);
 689
 690#endif /* CONFIG_CPU_FREQ */
 691
 692static 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
 698static int sparc64_timer_shutdown(struct clock_event_device *evt)
 699{
 700        tick_operations.disable_irq();
 701        return 0;
 702}
 703
 704static 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};
 712static DEFINE_PER_CPU(struct clock_event_device, sparc64_events);
 713
 714void __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
 739void 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
 769static struct clocksource clocksource_tick = {
 770        .rating         = 100,
 771        .mask           = CLOCKSOURCE_MASK(64),
 772        .flags          = CLOCK_SOURCE_IS_CONTINUOUS,
 773};
 774
 775static unsigned long tb_ticks_per_usec __read_mostly;
 776
 777void __delay(unsigned long loops)
 778{
 779        unsigned long bclock = get_tick();
 780
 781        while ((get_tick() - bclock) < loops)
 782                ;
 783}
 784EXPORT_SYMBOL(__delay);
 785
 786void udelay(unsigned long usecs)
 787{
 788        __delay(tb_ticks_per_usec * usecs);
 789}
 790EXPORT_SYMBOL(udelay);
 791
 792static u64 clocksource_tick_read(struct clocksource *cs)
 793{
 794        return get_tick();
 795}
 796
 797static 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
 817static 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
 832void __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
 849void __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
 879unsigned 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
 894int read_current_timer(unsigned long *timer_val)
 895{
 896        *timer_val = get_tick();
 897        return 0;
 898}
 899