linux/arch/powerpc/kernel/dt_cpu_ftrs.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright 2017, Nicholas Piggin, IBM Corporation
   4 */
   5
   6#define pr_fmt(fmt) "dt-cpu-ftrs: " fmt
   7
   8#include <linux/export.h>
   9#include <linux/init.h>
  10#include <linux/jump_label.h>
  11#include <linux/libfdt.h>
  12#include <linux/memblock.h>
  13#include <linux/printk.h>
  14#include <linux/sched.h>
  15#include <linux/string.h>
  16#include <linux/threads.h>
  17
  18#include <asm/cputable.h>
  19#include <asm/dt_cpu_ftrs.h>
  20#include <asm/mce.h>
  21#include <asm/mmu.h>
  22#include <asm/prom.h>
  23#include <asm/setup.h>
  24
  25
  26/* Device-tree visible constants follow */
  27#define ISA_V3_0B       3000
  28#define ISA_V3_1        3100
  29
  30#define USABLE_PR               (1U << 0)
  31#define USABLE_OS               (1U << 1)
  32#define USABLE_HV               (1U << 2)
  33
  34#define HV_SUPPORT_HFSCR        (1U << 0)
  35#define OS_SUPPORT_FSCR         (1U << 0)
  36
  37/* For parsing, we define all bits set as "NONE" case */
  38#define HV_SUPPORT_NONE         0xffffffffU
  39#define OS_SUPPORT_NONE         0xffffffffU
  40
  41struct dt_cpu_feature {
  42        const char *name;
  43        uint32_t isa;
  44        uint32_t usable_privilege;
  45        uint32_t hv_support;
  46        uint32_t os_support;
  47        uint32_t hfscr_bit_nr;
  48        uint32_t fscr_bit_nr;
  49        uint32_t hwcap_bit_nr;
  50        /* fdt parsing */
  51        unsigned long node;
  52        int enabled;
  53        int disabled;
  54};
  55
  56#define MMU_FTRS_HASH_BASE (MMU_FTRS_POWER8)
  57
  58#define COMMON_USER_BASE        (PPC_FEATURE_32 | PPC_FEATURE_64 | \
  59                                 PPC_FEATURE_ARCH_2_06 |\
  60                                 PPC_FEATURE_ICACHE_SNOOP)
  61#define COMMON_USER2_BASE       (PPC_FEATURE2_ARCH_2_07 | \
  62                                 PPC_FEATURE2_ISEL)
  63/*
  64 * Set up the base CPU
  65 */
  66
  67static int hv_mode;
  68
  69static struct {
  70        u64     lpcr;
  71        u64     hfscr;
  72        u64     fscr;
  73        u64     pcr;
  74} system_registers;
  75
  76static void (*init_pmu_registers)(void);
  77
  78static void __restore_cpu_cpufeatures(void)
  79{
  80        mtspr(SPRN_LPCR, system_registers.lpcr);
  81        if (hv_mode) {
  82                mtspr(SPRN_LPID, 0);
  83                mtspr(SPRN_HFSCR, system_registers.hfscr);
  84                mtspr(SPRN_PCR, system_registers.pcr);
  85        }
  86        mtspr(SPRN_FSCR, system_registers.fscr);
  87
  88        if (init_pmu_registers)
  89                init_pmu_registers();
  90}
  91
  92static char dt_cpu_name[64];
  93
  94static struct cpu_spec __initdata base_cpu_spec = {
  95        .cpu_name               = NULL,
  96        .cpu_features           = CPU_FTRS_DT_CPU_BASE,
  97        .cpu_user_features      = COMMON_USER_BASE,
  98        .cpu_user_features2     = COMMON_USER2_BASE,
  99        .mmu_features           = 0,
 100        .icache_bsize           = 32, /* minimum block size, fixed by */
 101        .dcache_bsize           = 32, /* cache info init.             */
 102        .num_pmcs               = 0,
 103        .pmc_type               = PPC_PMC_DEFAULT,
 104        .oprofile_cpu_type      = NULL,
 105        .cpu_setup              = NULL,
 106        .cpu_restore            = __restore_cpu_cpufeatures,
 107        .machine_check_early    = NULL,
 108        .platform               = NULL,
 109};
 110
 111static void __init cpufeatures_setup_cpu(void)
 112{
 113        set_cur_cpu_spec(&base_cpu_spec);
 114
 115        cur_cpu_spec->pvr_mask = -1;
 116        cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
 117
 118        /* Initialize the base environment -- clear FSCR/HFSCR.  */
 119        hv_mode = !!(mfmsr() & MSR_HV);
 120        if (hv_mode) {
 121                cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 122                mtspr(SPRN_HFSCR, 0);
 123        }
 124        mtspr(SPRN_FSCR, 0);
 125        mtspr(SPRN_PCR, PCR_MASK);
 126
 127        /*
 128         * LPCR does not get cleared, to match behaviour with secondaries
 129         * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
 130         * could clear LPCR too.
 131         */
 132}
 133
 134static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
 135{
 136        if (f->hv_support == HV_SUPPORT_NONE) {
 137        } else if (f->hv_support & HV_SUPPORT_HFSCR) {
 138                u64 hfscr = mfspr(SPRN_HFSCR);
 139                hfscr |= 1UL << f->hfscr_bit_nr;
 140                mtspr(SPRN_HFSCR, hfscr);
 141        } else {
 142                /* Does not have a known recipe */
 143                return 0;
 144        }
 145
 146        if (f->os_support == OS_SUPPORT_NONE) {
 147        } else if (f->os_support & OS_SUPPORT_FSCR) {
 148                u64 fscr = mfspr(SPRN_FSCR);
 149                fscr |= 1UL << f->fscr_bit_nr;
 150                mtspr(SPRN_FSCR, fscr);
 151        } else {
 152                /* Does not have a known recipe */
 153                return 0;
 154        }
 155
 156        if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 157                uint32_t word = f->hwcap_bit_nr / 32;
 158                uint32_t bit = f->hwcap_bit_nr % 32;
 159
 160                if (word == 0)
 161                        cur_cpu_spec->cpu_user_features |= 1U << bit;
 162                else if (word == 1)
 163                        cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 164                else
 165                        pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
 166        }
 167
 168        return 1;
 169}
 170
 171static int __init feat_enable(struct dt_cpu_feature *f)
 172{
 173        if (f->hv_support != HV_SUPPORT_NONE) {
 174                if (f->hfscr_bit_nr != -1) {
 175                        u64 hfscr = mfspr(SPRN_HFSCR);
 176                        hfscr |= 1UL << f->hfscr_bit_nr;
 177                        mtspr(SPRN_HFSCR, hfscr);
 178                }
 179        }
 180
 181        if (f->os_support != OS_SUPPORT_NONE) {
 182                if (f->fscr_bit_nr != -1) {
 183                        u64 fscr = mfspr(SPRN_FSCR);
 184                        fscr |= 1UL << f->fscr_bit_nr;
 185                        mtspr(SPRN_FSCR, fscr);
 186                }
 187        }
 188
 189        if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 190                uint32_t word = f->hwcap_bit_nr / 32;
 191                uint32_t bit = f->hwcap_bit_nr % 32;
 192
 193                if (word == 0)
 194                        cur_cpu_spec->cpu_user_features |= 1U << bit;
 195                else if (word == 1)
 196                        cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 197                else
 198                        pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
 199        }
 200
 201        return 1;
 202}
 203
 204static int __init feat_disable(struct dt_cpu_feature *f)
 205{
 206        return 0;
 207}
 208
 209static int __init feat_enable_hv(struct dt_cpu_feature *f)
 210{
 211        u64 lpcr;
 212
 213        if (!hv_mode) {
 214                pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
 215                return 0;
 216        }
 217
 218        mtspr(SPRN_LPID, 0);
 219
 220        lpcr = mfspr(SPRN_LPCR);
 221        lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
 222        mtspr(SPRN_LPCR, lpcr);
 223
 224        cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 225
 226        return 1;
 227}
 228
 229static int __init feat_enable_le(struct dt_cpu_feature *f)
 230{
 231        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
 232        return 1;
 233}
 234
 235static int __init feat_enable_smt(struct dt_cpu_feature *f)
 236{
 237        cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 238        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
 239        return 1;
 240}
 241
 242static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
 243{
 244        u64 lpcr;
 245
 246        /* Set PECE wakeup modes for ISA 207 */
 247        lpcr = mfspr(SPRN_LPCR);
 248        lpcr |=  LPCR_PECE0;
 249        lpcr |=  LPCR_PECE1;
 250        lpcr |=  LPCR_PECE2;
 251        mtspr(SPRN_LPCR, lpcr);
 252
 253        return 1;
 254}
 255
 256static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
 257{
 258        u64 lpcr;
 259
 260        /* Set PECE wakeup modes for ISAv3.0B */
 261        lpcr = mfspr(SPRN_LPCR);
 262        lpcr |=  LPCR_PECE0;
 263        lpcr |=  LPCR_PECE1;
 264        lpcr |=  LPCR_PECE2;
 265        mtspr(SPRN_LPCR, lpcr);
 266
 267        return 1;
 268}
 269
 270static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
 271{
 272        u64 lpcr;
 273
 274        lpcr = mfspr(SPRN_LPCR);
 275        lpcr &= ~LPCR_ISL;
 276
 277        /* VRMASD */
 278        lpcr |= LPCR_VPM0;
 279        lpcr &= ~LPCR_VPM1;
 280        lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
 281        mtspr(SPRN_LPCR, lpcr);
 282
 283        cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 284        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 285
 286        return 1;
 287}
 288
 289static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
 290{
 291        u64 lpcr;
 292
 293        lpcr = mfspr(SPRN_LPCR);
 294        lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
 295        mtspr(SPRN_LPCR, lpcr);
 296
 297        cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 298        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 299
 300        return 1;
 301}
 302
 303
 304static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
 305{
 306#ifdef CONFIG_PPC_RADIX_MMU
 307        cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
 308        cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 309        cur_cpu_spec->mmu_features |= MMU_FTR_GTSE;
 310        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 311
 312        return 1;
 313#endif
 314        return 0;
 315}
 316
 317static int __init feat_enable_dscr(struct dt_cpu_feature *f)
 318{
 319        u64 lpcr;
 320
 321        /*
 322         * Linux relies on FSCR[DSCR] being clear, so that we can take the
 323         * facility unavailable interrupt and track the task's usage of DSCR.
 324         * See facility_unavailable_exception().
 325         * Clear the bit here so that feat_enable() doesn't set it.
 326         */
 327        f->fscr_bit_nr = -1;
 328
 329        feat_enable(f);
 330
 331        lpcr = mfspr(SPRN_LPCR);
 332        lpcr &= ~LPCR_DPFD;
 333        lpcr |=  (4UL << LPCR_DPFD_SH);
 334        mtspr(SPRN_LPCR, lpcr);
 335
 336        return 1;
 337}
 338
 339static void hfscr_pmu_enable(void)
 340{
 341        u64 hfscr = mfspr(SPRN_HFSCR);
 342        hfscr |= PPC_BIT(60);
 343        mtspr(SPRN_HFSCR, hfscr);
 344}
 345
 346static void init_pmu_power8(void)
 347{
 348        if (hv_mode) {
 349                mtspr(SPRN_MMCRC, 0);
 350                mtspr(SPRN_MMCRH, 0);
 351        }
 352
 353        mtspr(SPRN_MMCRA, 0);
 354        mtspr(SPRN_MMCR0, 0);
 355        mtspr(SPRN_MMCR1, 0);
 356        mtspr(SPRN_MMCR2, 0);
 357        mtspr(SPRN_MMCRS, 0);
 358}
 359
 360static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
 361{
 362        cur_cpu_spec->platform = "power8";
 363        cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
 364
 365        return 1;
 366}
 367
 368static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
 369{
 370        hfscr_pmu_enable();
 371
 372        init_pmu_power8();
 373        init_pmu_registers = init_pmu_power8;
 374
 375        cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 376        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 377        if (pvr_version_is(PVR_POWER8E))
 378                cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
 379
 380        cur_cpu_spec->num_pmcs          = 6;
 381        cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 382        cur_cpu_spec->oprofile_cpu_type = "ppc64/power8";
 383
 384        return 1;
 385}
 386
 387static void init_pmu_power9(void)
 388{
 389        if (hv_mode)
 390                mtspr(SPRN_MMCRC, 0);
 391
 392        mtspr(SPRN_MMCRA, 0);
 393        mtspr(SPRN_MMCR0, 0);
 394        mtspr(SPRN_MMCR1, 0);
 395        mtspr(SPRN_MMCR2, 0);
 396}
 397
 398static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
 399{
 400        cur_cpu_spec->platform = "power9";
 401        cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
 402
 403        return 1;
 404}
 405
 406static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
 407{
 408        hfscr_pmu_enable();
 409
 410        init_pmu_power9();
 411        init_pmu_registers = init_pmu_power9;
 412
 413        cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 414        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 415
 416        cur_cpu_spec->num_pmcs          = 6;
 417        cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 418        cur_cpu_spec->oprofile_cpu_type = "ppc64/power9";
 419
 420        return 1;
 421}
 422
 423static void init_pmu_power10(void)
 424{
 425        init_pmu_power9();
 426
 427        mtspr(SPRN_MMCR3, 0);
 428        mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
 429        mtspr(SPRN_MMCR0, MMCR0_PMCCEXT);
 430}
 431
 432static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
 433{
 434        hfscr_pmu_enable();
 435
 436        init_pmu_power10();
 437        init_pmu_registers = init_pmu_power10;
 438
 439        cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 440        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 441
 442        cur_cpu_spec->num_pmcs          = 6;
 443        cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 444        cur_cpu_spec->oprofile_cpu_type = "ppc64/power10";
 445
 446        return 1;
 447}
 448
 449static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
 450{
 451        cur_cpu_spec->platform = "power10";
 452        cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
 453
 454        return 1;
 455}
 456
 457static int __init feat_enable_tm(struct dt_cpu_feature *f)
 458{
 459#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 460        feat_enable(f);
 461        cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
 462        return 1;
 463#endif
 464        return 0;
 465}
 466
 467static int __init feat_enable_fp(struct dt_cpu_feature *f)
 468{
 469        feat_enable(f);
 470        cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
 471
 472        return 1;
 473}
 474
 475static int __init feat_enable_vector(struct dt_cpu_feature *f)
 476{
 477#ifdef CONFIG_ALTIVEC
 478        feat_enable(f);
 479        cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
 480        cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
 481        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
 482
 483        return 1;
 484#endif
 485        return 0;
 486}
 487
 488static int __init feat_enable_vsx(struct dt_cpu_feature *f)
 489{
 490#ifdef CONFIG_VSX
 491        feat_enable(f);
 492        cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
 493        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
 494
 495        return 1;
 496#endif
 497        return 0;
 498}
 499
 500static int __init feat_enable_purr(struct dt_cpu_feature *f)
 501{
 502        cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
 503
 504        return 1;
 505}
 506
 507static int __init feat_enable_ebb(struct dt_cpu_feature *f)
 508{
 509        /*
 510         * PPC_FEATURE2_EBB is enabled in PMU init code because it has
 511         * historically been related to the PMU facility. This may have
 512         * to be decoupled if EBB becomes more generic. For now, follow
 513         * existing convention.
 514         */
 515        f->hwcap_bit_nr = -1;
 516        feat_enable(f);
 517
 518        return 1;
 519}
 520
 521static int __init feat_enable_dbell(struct dt_cpu_feature *f)
 522{
 523        u64 lpcr;
 524
 525        /* P9 has an HFSCR for privileged state */
 526        feat_enable(f);
 527
 528        cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
 529
 530        lpcr = mfspr(SPRN_LPCR);
 531        lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
 532        mtspr(SPRN_LPCR, lpcr);
 533
 534        return 1;
 535}
 536
 537static int __init feat_enable_hvi(struct dt_cpu_feature *f)
 538{
 539        u64 lpcr;
 540
 541        /*
 542         * POWER9 XIVE interrupts including in OPAL XICS compatibility
 543         * are always delivered as hypervisor virtualization interrupts (HVI)
 544         * rather than EE.
 545         *
 546         * However LPES0 is not set here, in the chance that an EE does get
 547         * delivered to the host somehow, the EE handler would not expect it
 548         * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
 549         * happen if there is a bug in interrupt controller code, or IC is
 550         * misconfigured in systemsim.
 551         */
 552
 553        lpcr = mfspr(SPRN_LPCR);
 554        lpcr |= LPCR_HVICE;     /* enable hvi interrupts */
 555        lpcr |= LPCR_HEIC;      /* disable ee interrupts when MSR_HV */
 556        lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
 557        mtspr(SPRN_LPCR, lpcr);
 558
 559        return 1;
 560}
 561
 562static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
 563{
 564        cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
 565
 566        return 1;
 567}
 568
 569static int __init feat_enable_mma(struct dt_cpu_feature *f)
 570{
 571        u64 pcr;
 572
 573        feat_enable(f);
 574        pcr = mfspr(SPRN_PCR);
 575        pcr &= ~PCR_MMA_DIS;
 576        mtspr(SPRN_PCR, pcr);
 577
 578        return 1;
 579}
 580
 581struct dt_cpu_feature_match {
 582        const char *name;
 583        int (*enable)(struct dt_cpu_feature *f);
 584        u64 cpu_ftr_bit_mask;
 585};
 586
 587static struct dt_cpu_feature_match __initdata
 588                dt_cpu_feature_match_table[] = {
 589        {"hypervisor", feat_enable_hv, 0},
 590        {"big-endian", feat_enable, 0},
 591        {"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
 592        {"smt", feat_enable_smt, 0},
 593        {"interrupt-facilities", feat_enable, 0},
 594        {"system-call-vectored", feat_enable, 0},
 595        {"timer-facilities", feat_enable, 0},
 596        {"timer-facilities-v3", feat_enable, 0},
 597        {"debug-facilities", feat_enable, 0},
 598        {"come-from-address-register", feat_enable, CPU_FTR_CFAR},
 599        {"branch-tracing", feat_enable, 0},
 600        {"floating-point", feat_enable_fp, 0},
 601        {"vector", feat_enable_vector, 0},
 602        {"vector-scalar", feat_enable_vsx, 0},
 603        {"vector-scalar-v3", feat_enable, 0},
 604        {"decimal-floating-point", feat_enable, 0},
 605        {"decimal-integer", feat_enable, 0},
 606        {"quadword-load-store", feat_enable, 0},
 607        {"vector-crypto", feat_enable, 0},
 608        {"mmu-hash", feat_enable_mmu_hash, 0},
 609        {"mmu-radix", feat_enable_mmu_radix, 0},
 610        {"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
 611        {"virtual-page-class-key-protection", feat_enable, 0},
 612        {"transactional-memory", feat_enable_tm, CPU_FTR_TM},
 613        {"transactional-memory-v3", feat_enable_tm, 0},
 614        {"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
 615        {"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
 616        {"idle-nap", feat_enable_idle_nap, 0},
 617        /* alignment-interrupt-dsisr ignored */
 618        {"idle-stop", feat_enable_idle_stop, 0},
 619        {"machine-check-power8", feat_enable_mce_power8, 0},
 620        {"performance-monitor-power8", feat_enable_pmu_power8, 0},
 621        {"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
 622        {"event-based-branch", feat_enable_ebb, 0},
 623        {"target-address-register", feat_enable, 0},
 624        {"branch-history-rolling-buffer", feat_enable, 0},
 625        {"control-register", feat_enable, CPU_FTR_CTRL},
 626        {"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
 627        {"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
 628        {"processor-utilization-of-resources-register", feat_enable_purr, 0},
 629        {"no-execute", feat_enable, 0},
 630        {"strong-access-ordering", feat_enable, CPU_FTR_SAO},
 631        {"cache-inhibited-large-page", feat_enable_large_ci, 0},
 632        {"coprocessor-icswx", feat_enable, 0},
 633        {"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
 634        {"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
 635        {"wait", feat_enable, 0},
 636        {"atomic-memory-operations", feat_enable, 0},
 637        {"branch-v3", feat_enable, 0},
 638        {"copy-paste", feat_enable, 0},
 639        {"decimal-floating-point-v3", feat_enable, 0},
 640        {"decimal-integer-v3", feat_enable, 0},
 641        {"fixed-point-v3", feat_enable, 0},
 642        {"floating-point-v3", feat_enable, 0},
 643        {"group-start-register", feat_enable, 0},
 644        {"pc-relative-addressing", feat_enable, 0},
 645        {"machine-check-power9", feat_enable_mce_power9, 0},
 646        {"machine-check-power10", feat_enable_mce_power10, 0},
 647        {"performance-monitor-power9", feat_enable_pmu_power9, 0},
 648        {"performance-monitor-power10", feat_enable_pmu_power10, 0},
 649        {"event-based-branch-v3", feat_enable, 0},
 650        {"random-number-generator", feat_enable, 0},
 651        {"system-call-vectored", feat_disable, 0},
 652        {"trace-interrupt-v3", feat_enable, 0},
 653        {"vector-v3", feat_enable, 0},
 654        {"vector-binary128", feat_enable, 0},
 655        {"vector-binary16", feat_enable, 0},
 656        {"wait-v3", feat_enable, 0},
 657        {"prefix-instructions", feat_enable, 0},
 658        {"matrix-multiply-assist", feat_enable_mma, 0},
 659        {"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
 660};
 661
 662static bool __initdata using_dt_cpu_ftrs;
 663static bool __initdata enable_unknown = true;
 664
 665static int __init dt_cpu_ftrs_parse(char *str)
 666{
 667        if (!str)
 668                return 0;
 669
 670        if (!strcmp(str, "off"))
 671                using_dt_cpu_ftrs = false;
 672        else if (!strcmp(str, "known"))
 673                enable_unknown = false;
 674        else
 675                return 1;
 676
 677        return 0;
 678}
 679early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
 680
 681static void __init cpufeatures_setup_start(u32 isa)
 682{
 683        pr_info("setup for ISA %d\n", isa);
 684
 685        if (isa >= ISA_V3_0B) {
 686                cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
 687                cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
 688        }
 689
 690        if (isa >= ISA_V3_1) {
 691                cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
 692                cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
 693        }
 694}
 695
 696static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
 697{
 698        const struct dt_cpu_feature_match *m;
 699        bool known = false;
 700        int i;
 701
 702        for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
 703                m = &dt_cpu_feature_match_table[i];
 704                if (!strcmp(f->name, m->name)) {
 705                        known = true;
 706                        if (m->enable(f)) {
 707                                cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
 708                                break;
 709                        }
 710
 711                        pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
 712                                f->name);
 713                        return false;
 714                }
 715        }
 716
 717        if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
 718                pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
 719                        f->name);
 720                return false;
 721        }
 722
 723        if (known)
 724                pr_debug("enabling: %s\n", f->name);
 725        else
 726                pr_debug("enabling: %s (unknown)\n", f->name);
 727
 728        return true;
 729}
 730
 731/*
 732 * Handle POWER9 broadcast tlbie invalidation issue using
 733 * cpu feature flag.
 734 */
 735static __init void update_tlbie_feature_flag(unsigned long pvr)
 736{
 737        if (PVR_VER(pvr) == PVR_POWER9) {
 738                /*
 739                 * Set the tlbie feature flag for anything below
 740                 * Nimbus DD 2.3 and Cumulus DD 1.3
 741                 */
 742                if ((pvr & 0xe000) == 0) {
 743                        /* Nimbus */
 744                        if ((pvr & 0xfff) < 0x203)
 745                                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 746                } else if ((pvr & 0xc000) == 0) {
 747                        /* Cumulus */
 748                        if ((pvr & 0xfff) < 0x103)
 749                                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 750                } else {
 751                        WARN_ONCE(1, "Unknown PVR");
 752                        cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 753                }
 754
 755                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
 756        }
 757}
 758
 759static __init void cpufeatures_cpu_quirks(void)
 760{
 761        unsigned long version = mfspr(SPRN_PVR);
 762
 763        /*
 764         * Not all quirks can be derived from the cpufeatures device tree.
 765         */
 766        if ((version & 0xffffefff) == 0x004e0200) {
 767                /* DD2.0 has no feature flag */
 768                cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
 769        } else if ((version & 0xffffefff) == 0x004e0201) {
 770                cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 771                cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
 772        } else if ((version & 0xffffefff) == 0x004e0202) {
 773                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
 774                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
 775                cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 776        } else if ((version & 0xffff0000) == 0x004e0000) {
 777                /* DD2.1 and up have DD2_1 */
 778                cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 779        }
 780
 781        if ((version & 0xffff0000) == 0x004e0000) {
 782                cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
 783                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
 784        }
 785
 786        update_tlbie_feature_flag(version);
 787}
 788
 789static void __init cpufeatures_setup_finished(void)
 790{
 791        cpufeatures_cpu_quirks();
 792
 793        if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
 794                pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
 795                cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 796        }
 797
 798        /* Make sure powerpc_base_platform is non-NULL */
 799        powerpc_base_platform = cur_cpu_spec->platform;
 800
 801        system_registers.lpcr = mfspr(SPRN_LPCR);
 802        system_registers.hfscr = mfspr(SPRN_HFSCR);
 803        system_registers.fscr = mfspr(SPRN_FSCR);
 804        system_registers.pcr = mfspr(SPRN_PCR);
 805
 806        pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
 807                cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
 808}
 809
 810static int __init disabled_on_cmdline(void)
 811{
 812        unsigned long root, chosen;
 813        const char *p;
 814
 815        root = of_get_flat_dt_root();
 816        chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
 817        if (chosen == -FDT_ERR_NOTFOUND)
 818                return false;
 819
 820        p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
 821        if (!p)
 822                return false;
 823
 824        if (strstr(p, "dt_cpu_ftrs=off"))
 825                return true;
 826
 827        return false;
 828}
 829
 830static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
 831                                        int depth, void *data)
 832{
 833        if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
 834            && of_get_flat_dt_prop(node, "isa", NULL))
 835                return 1;
 836
 837        return 0;
 838}
 839
 840bool __init dt_cpu_ftrs_in_use(void)
 841{
 842        return using_dt_cpu_ftrs;
 843}
 844
 845bool __init dt_cpu_ftrs_init(void *fdt)
 846{
 847        using_dt_cpu_ftrs = false;
 848
 849        /* Setup and verify the FDT, if it fails we just bail */
 850        if (!early_init_dt_verify(fdt))
 851                return false;
 852
 853        if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
 854                return false;
 855
 856        if (disabled_on_cmdline())
 857                return false;
 858
 859        cpufeatures_setup_cpu();
 860
 861        using_dt_cpu_ftrs = true;
 862        return true;
 863}
 864
 865static int nr_dt_cpu_features;
 866static struct dt_cpu_feature *dt_cpu_features;
 867
 868static int __init process_cpufeatures_node(unsigned long node,
 869                                          const char *uname, int i)
 870{
 871        const __be32 *prop;
 872        struct dt_cpu_feature *f;
 873        int len;
 874
 875        f = &dt_cpu_features[i];
 876
 877        f->node = node;
 878
 879        f->name = uname;
 880
 881        prop = of_get_flat_dt_prop(node, "isa", &len);
 882        if (!prop) {
 883                pr_warn("%s: missing isa property\n", uname);
 884                return 0;
 885        }
 886        f->isa = be32_to_cpup(prop);
 887
 888        prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
 889        if (!prop) {
 890                pr_warn("%s: missing usable-privilege property", uname);
 891                return 0;
 892        }
 893        f->usable_privilege = be32_to_cpup(prop);
 894
 895        prop = of_get_flat_dt_prop(node, "hv-support", &len);
 896        if (prop)
 897                f->hv_support = be32_to_cpup(prop);
 898        else
 899                f->hv_support = HV_SUPPORT_NONE;
 900
 901        prop = of_get_flat_dt_prop(node, "os-support", &len);
 902        if (prop)
 903                f->os_support = be32_to_cpup(prop);
 904        else
 905                f->os_support = OS_SUPPORT_NONE;
 906
 907        prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
 908        if (prop)
 909                f->hfscr_bit_nr = be32_to_cpup(prop);
 910        else
 911                f->hfscr_bit_nr = -1;
 912        prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
 913        if (prop)
 914                f->fscr_bit_nr = be32_to_cpup(prop);
 915        else
 916                f->fscr_bit_nr = -1;
 917        prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
 918        if (prop)
 919                f->hwcap_bit_nr = be32_to_cpup(prop);
 920        else
 921                f->hwcap_bit_nr = -1;
 922
 923        if (f->usable_privilege & USABLE_HV) {
 924                if (!(mfmsr() & MSR_HV)) {
 925                        pr_warn("%s: HV feature passed to guest\n", uname);
 926                        return 0;
 927                }
 928
 929                if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
 930                        pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
 931                        return 0;
 932                }
 933
 934                if (f->hv_support == HV_SUPPORT_HFSCR) {
 935                        if (f->hfscr_bit_nr == -1) {
 936                                pr_warn("%s: missing hfscr_bit_nr\n", uname);
 937                                return 0;
 938                        }
 939                }
 940        } else {
 941                if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
 942                        pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
 943                        return 0;
 944                }
 945        }
 946
 947        if (f->usable_privilege & USABLE_OS) {
 948                if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
 949                        pr_warn("%s: unwanted fscr_bit_nr\n", uname);
 950                        return 0;
 951                }
 952
 953                if (f->os_support == OS_SUPPORT_FSCR) {
 954                        if (f->fscr_bit_nr == -1) {
 955                                pr_warn("%s: missing fscr_bit_nr\n", uname);
 956                                return 0;
 957                        }
 958                }
 959        } else {
 960                if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
 961                        pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
 962                        return 0;
 963                }
 964        }
 965
 966        if (!(f->usable_privilege & USABLE_PR)) {
 967                if (f->hwcap_bit_nr != -1) {
 968                        pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
 969                        return 0;
 970                }
 971        }
 972
 973        /* Do all the independent features in the first pass */
 974        if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
 975                if (cpufeatures_process_feature(f))
 976                        f->enabled = 1;
 977                else
 978                        f->disabled = 1;
 979        }
 980
 981        return 0;
 982}
 983
 984static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
 985{
 986        const __be32 *prop;
 987        int len;
 988        int nr_deps;
 989        int i;
 990
 991        if (f->enabled || f->disabled)
 992                return;
 993
 994        prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
 995        if (!prop) {
 996                pr_warn("%s: missing dependencies property", f->name);
 997                return;
 998        }
 999
1000        nr_deps = len / sizeof(int);
1001
1002        for (i = 0; i < nr_deps; i++) {
1003                unsigned long phandle = be32_to_cpu(prop[i]);
1004                int j;
1005
1006                for (j = 0; j < nr_dt_cpu_features; j++) {
1007                        struct dt_cpu_feature *d = &dt_cpu_features[j];
1008
1009                        if (of_get_flat_dt_phandle(d->node) == phandle) {
1010                                cpufeatures_deps_enable(d);
1011                                if (d->disabled) {
1012                                        f->disabled = 1;
1013                                        return;
1014                                }
1015                        }
1016                }
1017        }
1018
1019        if (cpufeatures_process_feature(f))
1020                f->enabled = 1;
1021        else
1022                f->disabled = 1;
1023}
1024
1025static int __init scan_cpufeatures_subnodes(unsigned long node,
1026                                          const char *uname,
1027                                          void *data)
1028{
1029        int *count = data;
1030
1031        process_cpufeatures_node(node, uname, *count);
1032
1033        (*count)++;
1034
1035        return 0;
1036}
1037
1038static int __init count_cpufeatures_subnodes(unsigned long node,
1039                                          const char *uname,
1040                                          void *data)
1041{
1042        int *count = data;
1043
1044        (*count)++;
1045
1046        return 0;
1047}
1048
1049static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1050                                            *uname, int depth, void *data)
1051{
1052        const __be32 *prop;
1053        int count, i;
1054        u32 isa;
1055
1056        /* We are scanning "ibm,powerpc-cpu-features" nodes only */
1057        if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1058                return 0;
1059
1060        prop = of_get_flat_dt_prop(node, "isa", NULL);
1061        if (!prop)
1062                /* We checked before, "can't happen" */
1063                return 0;
1064
1065        isa = be32_to_cpup(prop);
1066
1067        /* Count and allocate space for cpu features */
1068        of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1069                                                &nr_dt_cpu_features);
1070        dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1071        if (!dt_cpu_features)
1072                panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1073                      __func__,
1074                      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1075                      PAGE_SIZE);
1076
1077        cpufeatures_setup_start(isa);
1078
1079        /* Scan nodes into dt_cpu_features and enable those without deps  */
1080        count = 0;
1081        of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1082
1083        /* Recursive enable remaining features with dependencies */
1084        for (i = 0; i < nr_dt_cpu_features; i++) {
1085                struct dt_cpu_feature *f = &dt_cpu_features[i];
1086
1087                cpufeatures_deps_enable(f);
1088        }
1089
1090        prop = of_get_flat_dt_prop(node, "display-name", NULL);
1091        if (prop && strlen((char *)prop) != 0) {
1092                strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1093                cur_cpu_spec->cpu_name = dt_cpu_name;
1094        }
1095
1096        cpufeatures_setup_finished();
1097
1098        memblock_free(__pa(dt_cpu_features),
1099                        sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1100
1101        return 0;
1102}
1103
1104void __init dt_cpu_ftrs_scan(void)
1105{
1106        if (!using_dt_cpu_ftrs)
1107                return;
1108
1109        of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1110}
1111