linux/arch/powerpc/kernel/dt_cpu_ftrs.c
<<
>>
Prefs
   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/mmu.h>
  21#include <asm/oprofile_impl.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     lpcr_clear;
  72        u64     hfscr;
  73        u64     fscr;
  74        u64     pcr;
  75} system_registers;
  76
  77static void (*init_pmu_registers)(void);
  78
  79static void __restore_cpu_cpufeatures(void)
  80{
  81        u64 lpcr;
  82
  83        /*
  84         * LPCR is restored by the power on engine already. It can be changed
  85         * after early init e.g., by radix enable, and we have no unified API
  86         * for saving and restoring such SPRs.
  87         *
  88         * This ->restore hook should really be removed from idle and register
  89         * restore moved directly into the idle restore code, because this code
  90         * doesn't know how idle is implemented or what it needs restored here.
  91         *
  92         * The best we can do to accommodate secondary boot and idle restore
  93         * for now is "or" LPCR with existing.
  94         */
  95        lpcr = mfspr(SPRN_LPCR);
  96        lpcr |= system_registers.lpcr;
  97        lpcr &= ~system_registers.lpcr_clear;
  98        mtspr(SPRN_LPCR, lpcr);
  99        if (hv_mode) {
 100                mtspr(SPRN_LPID, 0);
 101                mtspr(SPRN_HFSCR, system_registers.hfscr);
 102                mtspr(SPRN_PCR, system_registers.pcr);
 103        }
 104        mtspr(SPRN_FSCR, system_registers.fscr);
 105
 106        if (init_pmu_registers)
 107                init_pmu_registers();
 108}
 109
 110static char dt_cpu_name[64];
 111
 112static struct cpu_spec __initdata base_cpu_spec = {
 113        .cpu_name               = NULL,
 114        .cpu_features           = CPU_FTRS_DT_CPU_BASE,
 115        .cpu_user_features      = COMMON_USER_BASE,
 116        .cpu_user_features2     = COMMON_USER2_BASE,
 117        .mmu_features           = 0,
 118        .icache_bsize           = 32, /* minimum block size, fixed by */
 119        .dcache_bsize           = 32, /* cache info init.             */
 120        .num_pmcs               = 0,
 121        .pmc_type               = PPC_PMC_DEFAULT,
 122        .oprofile_cpu_type      = NULL,
 123        .oprofile_type          = PPC_OPROFILE_INVALID,
 124        .cpu_setup              = NULL,
 125        .cpu_restore            = __restore_cpu_cpufeatures,
 126        .machine_check_early    = NULL,
 127        .platform               = NULL,
 128};
 129
 130static void __init cpufeatures_setup_cpu(void)
 131{
 132        set_cur_cpu_spec(&base_cpu_spec);
 133
 134        cur_cpu_spec->pvr_mask = -1;
 135        cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
 136
 137        /* Initialize the base environment -- clear FSCR/HFSCR.  */
 138        hv_mode = !!(mfmsr() & MSR_HV);
 139        if (hv_mode) {
 140                cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 141                mtspr(SPRN_HFSCR, 0);
 142        }
 143        mtspr(SPRN_FSCR, 0);
 144        mtspr(SPRN_PCR, PCR_MASK);
 145
 146        /*
 147         * LPCR does not get cleared, to match behaviour with secondaries
 148         * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
 149         * could clear LPCR too.
 150         */
 151}
 152
 153static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
 154{
 155        if (f->hv_support == HV_SUPPORT_NONE) {
 156        } else if (f->hv_support & HV_SUPPORT_HFSCR) {
 157                u64 hfscr = mfspr(SPRN_HFSCR);
 158                hfscr |= 1UL << f->hfscr_bit_nr;
 159                mtspr(SPRN_HFSCR, hfscr);
 160        } else {
 161                /* Does not have a known recipe */
 162                return 0;
 163        }
 164
 165        if (f->os_support == OS_SUPPORT_NONE) {
 166        } else if (f->os_support & OS_SUPPORT_FSCR) {
 167                u64 fscr = mfspr(SPRN_FSCR);
 168                fscr |= 1UL << f->fscr_bit_nr;
 169                mtspr(SPRN_FSCR, fscr);
 170        } else {
 171                /* Does not have a known recipe */
 172                return 0;
 173        }
 174
 175        if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 176                uint32_t word = f->hwcap_bit_nr / 32;
 177                uint32_t bit = f->hwcap_bit_nr % 32;
 178
 179                if (word == 0)
 180                        cur_cpu_spec->cpu_user_features |= 1U << bit;
 181                else if (word == 1)
 182                        cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 183                else
 184                        pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
 185        }
 186
 187        return 1;
 188}
 189
 190static int __init feat_enable(struct dt_cpu_feature *f)
 191{
 192        if (f->hv_support != HV_SUPPORT_NONE) {
 193                if (f->hfscr_bit_nr != -1) {
 194                        u64 hfscr = mfspr(SPRN_HFSCR);
 195                        hfscr |= 1UL << f->hfscr_bit_nr;
 196                        mtspr(SPRN_HFSCR, hfscr);
 197                }
 198        }
 199
 200        if (f->os_support != OS_SUPPORT_NONE) {
 201                if (f->fscr_bit_nr != -1) {
 202                        u64 fscr = mfspr(SPRN_FSCR);
 203                        fscr |= 1UL << f->fscr_bit_nr;
 204                        mtspr(SPRN_FSCR, fscr);
 205                }
 206        }
 207
 208        if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 209                uint32_t word = f->hwcap_bit_nr / 32;
 210                uint32_t bit = f->hwcap_bit_nr % 32;
 211
 212                if (word == 0)
 213                        cur_cpu_spec->cpu_user_features |= 1U << bit;
 214                else if (word == 1)
 215                        cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 216                else
 217                        pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
 218        }
 219
 220        return 1;
 221}
 222
 223static int __init feat_disable(struct dt_cpu_feature *f)
 224{
 225        return 0;
 226}
 227
 228static int __init feat_enable_hv(struct dt_cpu_feature *f)
 229{
 230        u64 lpcr;
 231
 232        if (!hv_mode) {
 233                pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
 234                return 0;
 235        }
 236
 237        mtspr(SPRN_LPID, 0);
 238
 239        lpcr = mfspr(SPRN_LPCR);
 240        lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
 241        mtspr(SPRN_LPCR, lpcr);
 242
 243        cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 244
 245        return 1;
 246}
 247
 248static int __init feat_enable_le(struct dt_cpu_feature *f)
 249{
 250        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
 251        return 1;
 252}
 253
 254static int __init feat_enable_smt(struct dt_cpu_feature *f)
 255{
 256        cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 257        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
 258        return 1;
 259}
 260
 261static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
 262{
 263        u64 lpcr;
 264
 265        /* Set PECE wakeup modes for ISA 207 */
 266        lpcr = mfspr(SPRN_LPCR);
 267        lpcr |=  LPCR_PECE0;
 268        lpcr |=  LPCR_PECE1;
 269        lpcr |=  LPCR_PECE2;
 270        mtspr(SPRN_LPCR, lpcr);
 271
 272        return 1;
 273}
 274
 275static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
 276{
 277        cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
 278
 279        return 1;
 280}
 281
 282static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
 283{
 284        u64 lpcr;
 285
 286        /* Set PECE wakeup modes for ISAv3.0B */
 287        lpcr = mfspr(SPRN_LPCR);
 288        lpcr |=  LPCR_PECE0;
 289        lpcr |=  LPCR_PECE1;
 290        lpcr |=  LPCR_PECE2;
 291        mtspr(SPRN_LPCR, lpcr);
 292
 293        return 1;
 294}
 295
 296static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
 297{
 298        u64 lpcr;
 299
 300        lpcr = mfspr(SPRN_LPCR);
 301        lpcr &= ~LPCR_ISL;
 302
 303        /* VRMASD */
 304        lpcr |= LPCR_VPM0;
 305        lpcr &= ~LPCR_VPM1;
 306        lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
 307        mtspr(SPRN_LPCR, lpcr);
 308
 309        cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 310        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 311
 312        return 1;
 313}
 314
 315static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
 316{
 317        u64 lpcr;
 318
 319        system_registers.lpcr_clear |= (LPCR_ISL | LPCR_UPRT | LPCR_HR);
 320        lpcr = mfspr(SPRN_LPCR);
 321        lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
 322        mtspr(SPRN_LPCR, lpcr);
 323
 324        cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 325        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 326
 327        return 1;
 328}
 329
 330
 331static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
 332{
 333#ifdef CONFIG_PPC_RADIX_MMU
 334        cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
 335        cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 336        cur_cpu_spec->mmu_features |= MMU_FTR_GTSE;
 337        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 338
 339        return 1;
 340#endif
 341        return 0;
 342}
 343
 344static int __init feat_enable_dscr(struct dt_cpu_feature *f)
 345{
 346        u64 lpcr;
 347
 348        /*
 349         * Linux relies on FSCR[DSCR] being clear, so that we can take the
 350         * facility unavailable interrupt and track the task's usage of DSCR.
 351         * See facility_unavailable_exception().
 352         * Clear the bit here so that feat_enable() doesn't set it.
 353         */
 354        f->fscr_bit_nr = -1;
 355
 356        feat_enable(f);
 357
 358        lpcr = mfspr(SPRN_LPCR);
 359        lpcr &= ~LPCR_DPFD;
 360        lpcr |=  (4UL << LPCR_DPFD_SH);
 361        mtspr(SPRN_LPCR, lpcr);
 362
 363        return 1;
 364}
 365
 366static void hfscr_pmu_enable(void)
 367{
 368        u64 hfscr = mfspr(SPRN_HFSCR);
 369        hfscr |= PPC_BIT(60);
 370        mtspr(SPRN_HFSCR, hfscr);
 371}
 372
 373static void init_pmu_power8(void)
 374{
 375        if (hv_mode) {
 376                mtspr(SPRN_MMCRC, 0);
 377                mtspr(SPRN_MMCRH, 0);
 378        }
 379
 380        mtspr(SPRN_MMCRA, 0);
 381        mtspr(SPRN_MMCR0, 0);
 382        mtspr(SPRN_MMCR1, 0);
 383        mtspr(SPRN_MMCR2, 0);
 384        mtspr(SPRN_MMCRS, 0);
 385}
 386
 387static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
 388{
 389        cur_cpu_spec->platform = "power8";
 390        cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
 391
 392        return 1;
 393}
 394
 395static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
 396{
 397        hfscr_pmu_enable();
 398
 399        init_pmu_power8();
 400        init_pmu_registers = init_pmu_power8;
 401
 402        cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 403        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 404        if (pvr_version_is(PVR_POWER8E))
 405                cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
 406
 407        cur_cpu_spec->num_pmcs          = 6;
 408        cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 409        cur_cpu_spec->oprofile_cpu_type = "ppc64/power8";
 410
 411        return 1;
 412}
 413
 414static void init_pmu_power9(void)
 415{
 416        if (hv_mode)
 417                mtspr(SPRN_MMCRC, 0);
 418
 419        mtspr(SPRN_MMCRA, 0);
 420        mtspr(SPRN_MMCR0, 0);
 421        mtspr(SPRN_MMCR1, 0);
 422        mtspr(SPRN_MMCR2, 0);
 423}
 424
 425static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
 426{
 427        cur_cpu_spec->platform = "power9";
 428        cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
 429
 430        return 1;
 431}
 432
 433static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
 434{
 435        hfscr_pmu_enable();
 436
 437        init_pmu_power9();
 438        init_pmu_registers = init_pmu_power9;
 439
 440        cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 441        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 442
 443        cur_cpu_spec->num_pmcs          = 6;
 444        cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 445        cur_cpu_spec->oprofile_cpu_type = "ppc64/power9";
 446
 447        return 1;
 448}
 449
 450static void init_pmu_power10(void)
 451{
 452        init_pmu_power9();
 453
 454        mtspr(SPRN_MMCR3, 0);
 455        mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
 456}
 457
 458static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
 459{
 460        hfscr_pmu_enable();
 461
 462        init_pmu_power10();
 463        init_pmu_registers = init_pmu_power10;
 464
 465        cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 466        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 467
 468        cur_cpu_spec->num_pmcs          = 6;
 469        cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 470        cur_cpu_spec->oprofile_cpu_type = "ppc64/power10";
 471
 472        return 1;
 473}
 474
 475static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
 476{
 477        cur_cpu_spec->platform = "power10";
 478        cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
 479
 480        return 1;
 481}
 482
 483static int __init feat_enable_tm(struct dt_cpu_feature *f)
 484{
 485#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 486        feat_enable(f);
 487        cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
 488        return 1;
 489#endif
 490        return 0;
 491}
 492
 493static int __init feat_enable_fp(struct dt_cpu_feature *f)
 494{
 495        feat_enable(f);
 496        cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
 497
 498        return 1;
 499}
 500
 501static int __init feat_enable_vector(struct dt_cpu_feature *f)
 502{
 503#ifdef CONFIG_ALTIVEC
 504        feat_enable(f);
 505        cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
 506        cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
 507        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
 508
 509        return 1;
 510#endif
 511        return 0;
 512}
 513
 514static int __init feat_enable_vsx(struct dt_cpu_feature *f)
 515{
 516#ifdef CONFIG_VSX
 517        feat_enable(f);
 518        cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
 519        cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
 520
 521        return 1;
 522#endif
 523        return 0;
 524}
 525
 526static int __init feat_enable_purr(struct dt_cpu_feature *f)
 527{
 528        cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
 529
 530        return 1;
 531}
 532
 533static int __init feat_enable_ebb(struct dt_cpu_feature *f)
 534{
 535        /*
 536         * PPC_FEATURE2_EBB is enabled in PMU init code because it has
 537         * historically been related to the PMU facility. This may have
 538         * to be decoupled if EBB becomes more generic. For now, follow
 539         * existing convention.
 540         */
 541        f->hwcap_bit_nr = -1;
 542        feat_enable(f);
 543
 544        return 1;
 545}
 546
 547static int __init feat_enable_dbell(struct dt_cpu_feature *f)
 548{
 549        u64 lpcr;
 550
 551        /* P9 has an HFSCR for privileged state */
 552        feat_enable(f);
 553
 554        cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
 555
 556        lpcr = mfspr(SPRN_LPCR);
 557        lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
 558        mtspr(SPRN_LPCR, lpcr);
 559
 560        return 1;
 561}
 562
 563static int __init feat_enable_hvi(struct dt_cpu_feature *f)
 564{
 565        u64 lpcr;
 566
 567        /*
 568         * POWER9 XIVE interrupts including in OPAL XICS compatibility
 569         * are always delivered as hypervisor virtualization interrupts (HVI)
 570         * rather than EE.
 571         *
 572         * However LPES0 is not set here, in the chance that an EE does get
 573         * delivered to the host somehow, the EE handler would not expect it
 574         * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
 575         * happen if there is a bug in interrupt controller code, or IC is
 576         * misconfigured in systemsim.
 577         */
 578
 579        lpcr = mfspr(SPRN_LPCR);
 580        lpcr |= LPCR_HVICE;     /* enable hvi interrupts */
 581        lpcr |= LPCR_HEIC;      /* disable ee interrupts when MSR_HV */
 582        lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
 583        mtspr(SPRN_LPCR, lpcr);
 584
 585        return 1;
 586}
 587
 588static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
 589{
 590        cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
 591
 592        return 1;
 593}
 594
 595static int __init feat_enable_mma(struct dt_cpu_feature *f)
 596{
 597        u64 pcr;
 598
 599        feat_enable(f);
 600        pcr = mfspr(SPRN_PCR);
 601        pcr &= ~PCR_MMA_DIS;
 602        mtspr(SPRN_PCR, pcr);
 603
 604        return 1;
 605}
 606
 607struct dt_cpu_feature_match {
 608        const char *name;
 609        int (*enable)(struct dt_cpu_feature *f);
 610        u64 cpu_ftr_bit_mask;
 611};
 612
 613static struct dt_cpu_feature_match __initdata
 614                dt_cpu_feature_match_table[] = {
 615        {"hypervisor", feat_enable_hv, 0},
 616        {"big-endian", feat_enable, 0},
 617        {"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
 618        {"smt", feat_enable_smt, 0},
 619        {"interrupt-facilities", feat_enable, 0},
 620        {"system-call-vectored", feat_enable, 0},
 621        {"timer-facilities", feat_enable, 0},
 622        {"timer-facilities-v3", feat_enable, 0},
 623        {"debug-facilities", feat_enable, 0},
 624        {"come-from-address-register", feat_enable, CPU_FTR_CFAR},
 625        {"branch-tracing", feat_enable, 0},
 626        {"floating-point", feat_enable_fp, 0},
 627        {"vector", feat_enable_vector, 0},
 628        {"vector-scalar", feat_enable_vsx, 0},
 629        {"vector-scalar-v3", feat_enable, 0},
 630        {"decimal-floating-point", feat_enable, 0},
 631        {"decimal-integer", feat_enable, 0},
 632        {"quadword-load-store", feat_enable, 0},
 633        {"vector-crypto", feat_enable, 0},
 634        {"mmu-hash", feat_enable_mmu_hash, 0},
 635        {"mmu-radix", feat_enable_mmu_radix, 0},
 636        {"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
 637        {"virtual-page-class-key-protection", feat_enable, 0},
 638        {"transactional-memory", feat_enable_tm, CPU_FTR_TM},
 639        {"transactional-memory-v3", feat_enable_tm, 0},
 640        {"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
 641        {"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
 642        {"idle-nap", feat_enable_idle_nap, 0},
 643        {"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
 644        {"idle-stop", feat_enable_idle_stop, 0},
 645        {"machine-check-power8", feat_enable_mce_power8, 0},
 646        {"performance-monitor-power8", feat_enable_pmu_power8, 0},
 647        {"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
 648        {"event-based-branch", feat_enable_ebb, 0},
 649        {"target-address-register", feat_enable, 0},
 650        {"branch-history-rolling-buffer", feat_enable, 0},
 651        {"control-register", feat_enable, CPU_FTR_CTRL},
 652        {"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
 653        {"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
 654        {"processor-utilization-of-resources-register", feat_enable_purr, 0},
 655        {"no-execute", feat_enable, 0},
 656        {"strong-access-ordering", feat_enable, CPU_FTR_SAO},
 657        {"cache-inhibited-large-page", feat_enable_large_ci, 0},
 658        {"coprocessor-icswx", feat_enable, 0},
 659        {"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
 660        {"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
 661        {"wait", feat_enable, 0},
 662        {"atomic-memory-operations", feat_enable, 0},
 663        {"branch-v3", feat_enable, 0},
 664        {"copy-paste", feat_enable, 0},
 665        {"decimal-floating-point-v3", feat_enable, 0},
 666        {"decimal-integer-v3", feat_enable, 0},
 667        {"fixed-point-v3", feat_enable, 0},
 668        {"floating-point-v3", feat_enable, 0},
 669        {"group-start-register", feat_enable, 0},
 670        {"pc-relative-addressing", feat_enable, 0},
 671        {"machine-check-power9", feat_enable_mce_power9, 0},
 672        {"machine-check-power10", feat_enable_mce_power10, 0},
 673        {"performance-monitor-power9", feat_enable_pmu_power9, 0},
 674        {"performance-monitor-power10", feat_enable_pmu_power10, 0},
 675        {"event-based-branch-v3", feat_enable, 0},
 676        {"random-number-generator", feat_enable, 0},
 677        {"system-call-vectored", feat_disable, 0},
 678        {"trace-interrupt-v3", feat_enable, 0},
 679        {"vector-v3", feat_enable, 0},
 680        {"vector-binary128", feat_enable, 0},
 681        {"vector-binary16", feat_enable, 0},
 682        {"wait-v3", feat_enable, 0},
 683        {"prefix-instructions", feat_enable, 0},
 684        {"matrix-multiply-assist", feat_enable_mma, 0},
 685        {"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
 686};
 687
 688static bool __initdata using_dt_cpu_ftrs;
 689static bool __initdata enable_unknown = true;
 690
 691static int __init dt_cpu_ftrs_parse(char *str)
 692{
 693        if (!str)
 694                return 0;
 695
 696        if (!strcmp(str, "off"))
 697                using_dt_cpu_ftrs = false;
 698        else if (!strcmp(str, "known"))
 699                enable_unknown = false;
 700        else
 701                return 1;
 702
 703        return 0;
 704}
 705early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
 706
 707static void __init cpufeatures_setup_start(u32 isa)
 708{
 709        pr_info("setup for ISA %d\n", isa);
 710
 711        if (isa >= ISA_V3_0B) {
 712                cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
 713                cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
 714        }
 715
 716        if (isa >= ISA_V3_1) {
 717                cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
 718                cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
 719        }
 720}
 721
 722static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
 723{
 724        const struct dt_cpu_feature_match *m;
 725        bool known = false;
 726        int i;
 727
 728        for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
 729                m = &dt_cpu_feature_match_table[i];
 730                if (!strcmp(f->name, m->name)) {
 731                        known = true;
 732                        if (m->enable(f)) {
 733                                cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
 734                                break;
 735                        }
 736
 737                        pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
 738                                f->name);
 739                        return false;
 740                }
 741        }
 742
 743        if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
 744                pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
 745                        f->name);
 746                return false;
 747        }
 748
 749        if (known)
 750                pr_debug("enabling: %s\n", f->name);
 751        else
 752                pr_debug("enabling: %s (unknown)\n", f->name);
 753
 754        return true;
 755}
 756
 757/*
 758 * Handle POWER9 broadcast tlbie invalidation issue using
 759 * cpu feature flag.
 760 */
 761static __init void update_tlbie_feature_flag(unsigned long pvr)
 762{
 763        if (PVR_VER(pvr) == PVR_POWER9) {
 764                /*
 765                 * Set the tlbie feature flag for anything below
 766                 * Nimbus DD 2.3 and Cumulus DD 1.3
 767                 */
 768                if ((pvr & 0xe000) == 0) {
 769                        /* Nimbus */
 770                        if ((pvr & 0xfff) < 0x203)
 771                                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 772                } else if ((pvr & 0xc000) == 0) {
 773                        /* Cumulus */
 774                        if ((pvr & 0xfff) < 0x103)
 775                                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 776                } else {
 777                        WARN_ONCE(1, "Unknown PVR");
 778                        cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 779                }
 780
 781                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
 782        }
 783}
 784
 785static __init void cpufeatures_cpu_quirks(void)
 786{
 787        unsigned long version = mfspr(SPRN_PVR);
 788
 789        /*
 790         * Not all quirks can be derived from the cpufeatures device tree.
 791         */
 792        if ((version & 0xffffefff) == 0x004e0200) {
 793                /* DD2.0 has no feature flag */
 794                cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
 795        } else if ((version & 0xffffefff) == 0x004e0201) {
 796                cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 797                cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
 798        } else if ((version & 0xffffefff) == 0x004e0202) {
 799                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
 800                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
 801                cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 802        } else if ((version & 0xffff0000) == 0x004e0000) {
 803                /* DD2.1 and up have DD2_1 */
 804                cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 805        }
 806
 807        if ((version & 0xffff0000) == 0x004e0000) {
 808                cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
 809                cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
 810        }
 811
 812        update_tlbie_feature_flag(version);
 813}
 814
 815static void __init cpufeatures_setup_finished(void)
 816{
 817        cpufeatures_cpu_quirks();
 818
 819        if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
 820                pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
 821                cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 822        }
 823
 824        /* Make sure powerpc_base_platform is non-NULL */
 825        powerpc_base_platform = cur_cpu_spec->platform;
 826
 827        system_registers.lpcr = mfspr(SPRN_LPCR);
 828        system_registers.hfscr = mfspr(SPRN_HFSCR);
 829        system_registers.fscr = mfspr(SPRN_FSCR);
 830        system_registers.pcr = mfspr(SPRN_PCR);
 831
 832        pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
 833                cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
 834}
 835
 836static int __init disabled_on_cmdline(void)
 837{
 838        unsigned long root, chosen;
 839        const char *p;
 840
 841        root = of_get_flat_dt_root();
 842        chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
 843        if (chosen == -FDT_ERR_NOTFOUND)
 844                return false;
 845
 846        p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
 847        if (!p)
 848                return false;
 849
 850        if (strstr(p, "dt_cpu_ftrs=off"))
 851                return true;
 852
 853        return false;
 854}
 855
 856static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
 857                                        int depth, void *data)
 858{
 859        if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
 860            && of_get_flat_dt_prop(node, "isa", NULL))
 861                return 1;
 862
 863        return 0;
 864}
 865
 866bool __init dt_cpu_ftrs_in_use(void)
 867{
 868        return using_dt_cpu_ftrs;
 869}
 870
 871bool __init dt_cpu_ftrs_init(void *fdt)
 872{
 873        using_dt_cpu_ftrs = false;
 874
 875        /* Setup and verify the FDT, if it fails we just bail */
 876        if (!early_init_dt_verify(fdt))
 877                return false;
 878
 879        if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
 880                return false;
 881
 882        if (disabled_on_cmdline())
 883                return false;
 884
 885        cpufeatures_setup_cpu();
 886
 887        using_dt_cpu_ftrs = true;
 888        return true;
 889}
 890
 891static int nr_dt_cpu_features;
 892static struct dt_cpu_feature *dt_cpu_features;
 893
 894static int __init process_cpufeatures_node(unsigned long node,
 895                                          const char *uname, int i)
 896{
 897        const __be32 *prop;
 898        struct dt_cpu_feature *f;
 899        int len;
 900
 901        f = &dt_cpu_features[i];
 902
 903        f->node = node;
 904
 905        f->name = uname;
 906
 907        prop = of_get_flat_dt_prop(node, "isa", &len);
 908        if (!prop) {
 909                pr_warn("%s: missing isa property\n", uname);
 910                return 0;
 911        }
 912        f->isa = be32_to_cpup(prop);
 913
 914        prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
 915        if (!prop) {
 916                pr_warn("%s: missing usable-privilege property", uname);
 917                return 0;
 918        }
 919        f->usable_privilege = be32_to_cpup(prop);
 920
 921        prop = of_get_flat_dt_prop(node, "hv-support", &len);
 922        if (prop)
 923                f->hv_support = be32_to_cpup(prop);
 924        else
 925                f->hv_support = HV_SUPPORT_NONE;
 926
 927        prop = of_get_flat_dt_prop(node, "os-support", &len);
 928        if (prop)
 929                f->os_support = be32_to_cpup(prop);
 930        else
 931                f->os_support = OS_SUPPORT_NONE;
 932
 933        prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
 934        if (prop)
 935                f->hfscr_bit_nr = be32_to_cpup(prop);
 936        else
 937                f->hfscr_bit_nr = -1;
 938        prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
 939        if (prop)
 940                f->fscr_bit_nr = be32_to_cpup(prop);
 941        else
 942                f->fscr_bit_nr = -1;
 943        prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
 944        if (prop)
 945                f->hwcap_bit_nr = be32_to_cpup(prop);
 946        else
 947                f->hwcap_bit_nr = -1;
 948
 949        if (f->usable_privilege & USABLE_HV) {
 950                if (!(mfmsr() & MSR_HV)) {
 951                        pr_warn("%s: HV feature passed to guest\n", uname);
 952                        return 0;
 953                }
 954
 955                if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
 956                        pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
 957                        return 0;
 958                }
 959
 960                if (f->hv_support == HV_SUPPORT_HFSCR) {
 961                        if (f->hfscr_bit_nr == -1) {
 962                                pr_warn("%s: missing hfscr_bit_nr\n", uname);
 963                                return 0;
 964                        }
 965                }
 966        } else {
 967                if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
 968                        pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
 969                        return 0;
 970                }
 971        }
 972
 973        if (f->usable_privilege & USABLE_OS) {
 974                if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
 975                        pr_warn("%s: unwanted fscr_bit_nr\n", uname);
 976                        return 0;
 977                }
 978
 979                if (f->os_support == OS_SUPPORT_FSCR) {
 980                        if (f->fscr_bit_nr == -1) {
 981                                pr_warn("%s: missing fscr_bit_nr\n", uname);
 982                                return 0;
 983                        }
 984                }
 985        } else {
 986                if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
 987                        pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
 988                        return 0;
 989                }
 990        }
 991
 992        if (!(f->usable_privilege & USABLE_PR)) {
 993                if (f->hwcap_bit_nr != -1) {
 994                        pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
 995                        return 0;
 996                }
 997        }
 998
 999        /* Do all the independent features in the first pass */
1000        if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
1001                if (cpufeatures_process_feature(f))
1002                        f->enabled = 1;
1003                else
1004                        f->disabled = 1;
1005        }
1006
1007        return 0;
1008}
1009
1010static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
1011{
1012        const __be32 *prop;
1013        int len;
1014        int nr_deps;
1015        int i;
1016
1017        if (f->enabled || f->disabled)
1018                return;
1019
1020        prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
1021        if (!prop) {
1022                pr_warn("%s: missing dependencies property", f->name);
1023                return;
1024        }
1025
1026        nr_deps = len / sizeof(int);
1027
1028        for (i = 0; i < nr_deps; i++) {
1029                unsigned long phandle = be32_to_cpu(prop[i]);
1030                int j;
1031
1032                for (j = 0; j < nr_dt_cpu_features; j++) {
1033                        struct dt_cpu_feature *d = &dt_cpu_features[j];
1034
1035                        if (of_get_flat_dt_phandle(d->node) == phandle) {
1036                                cpufeatures_deps_enable(d);
1037                                if (d->disabled) {
1038                                        f->disabled = 1;
1039                                        return;
1040                                }
1041                        }
1042                }
1043        }
1044
1045        if (cpufeatures_process_feature(f))
1046                f->enabled = 1;
1047        else
1048                f->disabled = 1;
1049}
1050
1051static int __init scan_cpufeatures_subnodes(unsigned long node,
1052                                          const char *uname,
1053                                          void *data)
1054{
1055        int *count = data;
1056
1057        process_cpufeatures_node(node, uname, *count);
1058
1059        (*count)++;
1060
1061        return 0;
1062}
1063
1064static int __init count_cpufeatures_subnodes(unsigned long node,
1065                                          const char *uname,
1066                                          void *data)
1067{
1068        int *count = data;
1069
1070        (*count)++;
1071
1072        return 0;
1073}
1074
1075static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1076                                            *uname, int depth, void *data)
1077{
1078        const __be32 *prop;
1079        int count, i;
1080        u32 isa;
1081
1082        /* We are scanning "ibm,powerpc-cpu-features" nodes only */
1083        if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1084                return 0;
1085
1086        prop = of_get_flat_dt_prop(node, "isa", NULL);
1087        if (!prop)
1088                /* We checked before, "can't happen" */
1089                return 0;
1090
1091        isa = be32_to_cpup(prop);
1092
1093        /* Count and allocate space for cpu features */
1094        of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1095                                                &nr_dt_cpu_features);
1096        dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1097        if (!dt_cpu_features)
1098                panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1099                      __func__,
1100                      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1101                      PAGE_SIZE);
1102
1103        cpufeatures_setup_start(isa);
1104
1105        /* Scan nodes into dt_cpu_features and enable those without deps  */
1106        count = 0;
1107        of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1108
1109        /* Recursive enable remaining features with dependencies */
1110        for (i = 0; i < nr_dt_cpu_features; i++) {
1111                struct dt_cpu_feature *f = &dt_cpu_features[i];
1112
1113                cpufeatures_deps_enable(f);
1114        }
1115
1116        prop = of_get_flat_dt_prop(node, "display-name", NULL);
1117        if (prop && strlen((char *)prop) != 0) {
1118                strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1119                cur_cpu_spec->cpu_name = dt_cpu_name;
1120        }
1121
1122        cpufeatures_setup_finished();
1123
1124        memblock_free(__pa(dt_cpu_features),
1125                        sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1126
1127        return 0;
1128}
1129
1130void __init dt_cpu_ftrs_scan(void)
1131{
1132        if (!using_dt_cpu_ftrs)
1133                return;
1134
1135        of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1136}
1137