arch/powerpc/kernel/dt_cpu_ftrs.c

   1 /*
   2  * Copyright 2017, Nicholas Piggin, IBM Corporation
   3  * Licensed under GPLv2.
   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_V2_07B      2070
  28 #define ISA_V3_0B       3000
  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
  41 struct 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 CPU_FTRS_BASE \
  57            (CPU_FTR_USE_TB | \
  58             CPU_FTR_LWSYNC | \
  59             CPU_FTR_FPU_UNAVAILABLE |\
  60             CPU_FTR_NODSISRALIGN |\
  61             CPU_FTR_NOEXECUTE |\
  62             CPU_FTR_COHERENT_ICACHE | \
  63             CPU_FTR_STCX_CHECKS_ADDRESS |\
  64             CPU_FTR_POPCNTB | CPU_FTR_POPCNTD | \
  65             CPU_FTR_DAWR | \
  66             CPU_FTR_ARCH_206 |\
  67             CPU_FTR_ARCH_207S)
  68
  69 #define MMU_FTRS_HASH_BASE (MMU_FTRS_POWER8)
  70
  71 #define COMMON_USER_BASE        (PPC_FEATURE_32 | PPC_FEATURE_64 | \
  72                                  PPC_FEATURE_ARCH_2_06 |\
  73                                  PPC_FEATURE_ICACHE_SNOOP)
  74 #define COMMON_USER2_BASE       (PPC_FEATURE2_ARCH_2_07 | \
  75                                  PPC_FEATURE2_ISEL)
  76 /*
  77  * Set up the base CPU
  78  */
  79
  80 extern void __flush_tlb_power8(unsigned int action);
  81 extern void __flush_tlb_power9(unsigned int action);
  82 extern long __machine_check_early_realmode_p8(struct pt_regs *regs);
  83 extern long __machine_check_early_realmode_p9(struct pt_regs *regs);
  84
  85 static int hv_mode;
  86
  87 static struct {
  88         u64     lpcr;
  89         u64     hfscr;
  90         u64     fscr;
  91 } system_registers;
  92
  93 static void (*init_pmu_registers)(void);
  94
  95 static void cpufeatures_flush_tlb(void)
  96 {
  97         /*
  98          * This is a temporary measure to keep equivalent TLB flush as the
  99          * cputable based setup code.
 100          */
 101         switch (PVR_VER(mfspr(SPRN_PVR))) {
 102         case PVR_POWER8:
 103         case PVR_POWER8E:
 104         case PVR_POWER8NVL:
 105                 __flush_tlb_power8(POWER8_TLB_SETS);
 106                 break;
 107         case PVR_POWER9:
 108                 __flush_tlb_power9(POWER9_TLB_SETS_HASH);
 109                 break;
 110         default:
 111                 pr_err("unknown CPU version for boot TLB flush\n");
 112                 break;
 113         }
 114 }
 115
 116 static void __restore_cpu_cpufeatures(void)
 117 {
 118         /*
 119          * LPCR is restored by the power on engine already. It can be changed
 120          * after early init e.g., by radix enable, and we have no unified API
 121          * for saving and restoring such SPRs.
 122          *
 123          * This ->restore hook should really be removed from idle and register
 124          * restore moved directly into the idle restore code, because this code
 125          * doesn't know how idle is implemented or what it needs restored here.
 126          *
 127          * The best we can do to accommodate secondary boot and idle restore
 128          * for now is "or" LPCR with existing.
 129          */
 130
 131         mtspr(SPRN_LPCR, system_registers.lpcr | mfspr(SPRN_LPCR));
 132         if (hv_mode) {
 133                 mtspr(SPRN_LPID, 0);
 134                 mtspr(SPRN_HFSCR, system_registers.hfscr);
 135         }
 136         mtspr(SPRN_FSCR, system_registers.fscr);
 137
 138         if (init_pmu_registers)
 139                 init_pmu_registers();
 140
 141         cpufeatures_flush_tlb();
 142 }
 143
 144 static char dt_cpu_name[64];
 145
 146 static struct cpu_spec __initdata base_cpu_spec = {
 147         .cpu_name               = NULL,
 148         .cpu_features           = CPU_FTRS_BASE,
 149         .cpu_user_features      = COMMON_USER_BASE,
 150         .cpu_user_features2     = COMMON_USER2_BASE,
 151         .mmu_features           = 0,
 152         .icache_bsize           = 32, /* minimum block size, fixed by */
 153         .dcache_bsize           = 32, /* cache info init.             */
 154         .num_pmcs               = 0,
 155         .pmc_type               = PPC_PMC_DEFAULT,
 156         .oprofile_cpu_type      = NULL,
 157         .oprofile_type          = PPC_OPROFILE_INVALID,
 158         .cpu_setup              = NULL,
 159         .cpu_restore            = __restore_cpu_cpufeatures,
 160         .flush_tlb              = NULL,
 161         .machine_check_early    = NULL,
 162         .platform               = NULL,
 163 };
 164
 165 static void __init cpufeatures_setup_cpu(void)
 166 {
 167         set_cur_cpu_spec(&base_cpu_spec);
 168
 169         cur_cpu_spec->pvr_mask = -1;
 170         cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
 171
 172         /* Initialize the base environment -- clear FSCR/HFSCR.  */
 173         hv_mode = !!(mfmsr() & MSR_HV);
 174         if (hv_mode) {
 175                 /* CPU_FTR_HVMODE is used early in PACA setup */
 176                 cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 177                 mtspr(SPRN_HFSCR, 0);
 178         }
 179         mtspr(SPRN_FSCR, 0);
 180
 181         /*
 182          * LPCR does not get cleared, to match behaviour with secondaries
 183          * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
 184          * could clear LPCR too.
 185          */
 186 }
 187
 188 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
 189 {
 190         if (f->hv_support == HV_SUPPORT_NONE) {
 191         } else if (f->hv_support & HV_SUPPORT_HFSCR) {
 192                 u64 hfscr = mfspr(SPRN_HFSCR);
 193                 hfscr |= 1UL << f->hfscr_bit_nr;
 194                 mtspr(SPRN_HFSCR, hfscr);
 195         } else {
 196                 /* Does not have a known recipe */
 197                 return 0;
 198         }
 199
 200         if (f->os_support == OS_SUPPORT_NONE) {
 201         } else if (f->os_support & OS_SUPPORT_FSCR) {
 202                 u64 fscr = mfspr(SPRN_FSCR);
 203                 fscr |= 1UL << f->fscr_bit_nr;
 204                 mtspr(SPRN_FSCR, fscr);
 205         } else {
 206                 /* Does not have a known recipe */
 207                 return 0;
 208         }
 209
 210         if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 211                 uint32_t word = f->hwcap_bit_nr / 32;
 212                 uint32_t bit = f->hwcap_bit_nr % 32;
 213
 214                 if (word == 0)
 215                         cur_cpu_spec->cpu_user_features |= 1U << bit;
 216                 else if (word == 1)
 217                         cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 218                 else
 219                         pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
 220         }
 221
 222         return 1;
 223 }
 224
 225 static int __init feat_enable(struct dt_cpu_feature *f)
 226 {
 227         if (f->hv_support != HV_SUPPORT_NONE) {
 228                 if (f->hfscr_bit_nr != -1) {
 229                         u64 hfscr = mfspr(SPRN_HFSCR);
 230                         hfscr |= 1UL << f->hfscr_bit_nr;
 231                         mtspr(SPRN_HFSCR, hfscr);
 232                 }
 233         }
 234
 235         if (f->os_support != OS_SUPPORT_NONE) {
 236                 if (f->fscr_bit_nr != -1) {
 237                         u64 fscr = mfspr(SPRN_FSCR);
 238                         fscr |= 1UL << f->fscr_bit_nr;
 239                         mtspr(SPRN_FSCR, fscr);
 240                 }
 241         }
 242
 243         if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 244                 uint32_t word = f->hwcap_bit_nr / 32;
 245                 uint32_t bit = f->hwcap_bit_nr % 32;
 246
 247                 if (word == 0)
 248                         cur_cpu_spec->cpu_user_features |= 1U << bit;
 249                 else if (word == 1)
 250                         cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 251                 else
 252                         pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
 253         }
 254
 255         return 1;
 256 }
 257
 258 static int __init feat_disable(struct dt_cpu_feature *f)
 259 {
 260         return 0;
 261 }
 262
 263 static int __init feat_enable_hv(struct dt_cpu_feature *f)
 264 {
 265         u64 lpcr;
 266
 267         if (!hv_mode) {
 268                 pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
 269                 return 0;
 270         }
 271
 272         mtspr(SPRN_LPID, 0);
 273
 274         lpcr = mfspr(SPRN_LPCR);
 275         lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
 276         mtspr(SPRN_LPCR, lpcr);
 277
 278         cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 279
 280         return 1;
 281 }
 282
 283 static int __init feat_enable_le(struct dt_cpu_feature *f)
 284 {
 285         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
 286         return 1;
 287 }
 288
 289 static int __init feat_enable_smt(struct dt_cpu_feature *f)
 290 {
 291         cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 292         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
 293         return 1;
 294 }
 295
 296 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
 297 {
 298         u64 lpcr;
 299
 300         /* Set PECE wakeup modes for ISA 207 */
 301         lpcr = mfspr(SPRN_LPCR);
 302         lpcr |=  LPCR_PECE0;
 303         lpcr |=  LPCR_PECE1;
 304         lpcr |=  LPCR_PECE2;
 305         mtspr(SPRN_LPCR, lpcr);
 306
 307         return 1;
 308 }
 309
 310 static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
 311 {
 312         cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
 313
 314         return 1;
 315 }
 316
 317 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
 318 {
 319         u64 lpcr;
 320
 321         /* Set PECE wakeup modes for ISAv3.0B */
 322         lpcr = mfspr(SPRN_LPCR);
 323         lpcr |=  LPCR_PECE0;
 324         lpcr |=  LPCR_PECE1;
 325         lpcr |=  LPCR_PECE2;
 326         mtspr(SPRN_LPCR, lpcr);
 327
 328         return 1;
 329 }
 330
 331 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
 332 {
 333         u64 lpcr;
 334
 335         lpcr = mfspr(SPRN_LPCR);
 336         lpcr &= ~LPCR_ISL;
 337
 338         /* VRMASD */
 339         lpcr |= LPCR_VPM0;
 340         lpcr &= ~LPCR_VPM1;
 341         lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
 342         mtspr(SPRN_LPCR, lpcr);
 343
 344         cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 345         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 346
 347         return 1;
 348 }
 349
 350 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
 351 {
 352         u64 lpcr;
 353
 354         lpcr = mfspr(SPRN_LPCR);
 355         lpcr &= ~LPCR_ISL;
 356         mtspr(SPRN_LPCR, lpcr);
 357
 358         cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 359         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 360
 361         return 1;
 362 }
 363
 364
 365 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
 366 {
 367 #ifdef CONFIG_PPC_RADIX_MMU
 368         cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
 369         cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 370         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 371
 372         return 1;
 373 #endif
 374         return 0;
 375 }
 376
 377 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
 378 {
 379         u64 lpcr;
 380
 381         feat_enable(f);
 382
 383         lpcr = mfspr(SPRN_LPCR);
 384         lpcr &= ~LPCR_DPFD;
 385         lpcr |=  (4UL << LPCR_DPFD_SH);
 386         mtspr(SPRN_LPCR, lpcr);
 387
 388         return 1;
 389 }
 390
 391 static void hfscr_pmu_enable(void)
 392 {
 393         u64 hfscr = mfspr(SPRN_HFSCR);
 394         hfscr |= PPC_BIT(60);
 395         mtspr(SPRN_HFSCR, hfscr);
 396 }
 397
 398 static void init_pmu_power8(void)
 399 {
 400         if (hv_mode) {
 401                 mtspr(SPRN_MMCRC, 0);
 402                 mtspr(SPRN_MMCRH, 0);
 403         }
 404
 405         mtspr(SPRN_MMCRA, 0);
 406         mtspr(SPRN_MMCR0, 0);
 407         mtspr(SPRN_MMCR1, 0);
 408         mtspr(SPRN_MMCR2, 0);
 409         mtspr(SPRN_MMCRS, 0);
 410 }
 411
 412 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
 413 {
 414         cur_cpu_spec->platform = "power8";
 415         cur_cpu_spec->flush_tlb = __flush_tlb_power8;
 416         cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
 417
 418         return 1;
 419 }
 420
 421 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
 422 {
 423         hfscr_pmu_enable();
 424
 425         init_pmu_power8();
 426         init_pmu_registers = init_pmu_power8;
 427
 428         cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 429         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 430         if (pvr_version_is(PVR_POWER8E))
 431                 cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
 432
 433         cur_cpu_spec->num_pmcs          = 6;
 434         cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 435         cur_cpu_spec->oprofile_cpu_type = "ppc64/power8";
 436
 437         return 1;
 438 }
 439
 440 static void init_pmu_power9(void)
 441 {
 442         if (hv_mode)
 443                 mtspr(SPRN_MMCRC, 0);
 444
 445         mtspr(SPRN_MMCRA, 0);
 446         mtspr(SPRN_MMCR0, 0);
 447         mtspr(SPRN_MMCR1, 0);
 448         mtspr(SPRN_MMCR2, 0);
 449 }
 450
 451 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
 452 {
 453         cur_cpu_spec->platform = "power9";
 454         cur_cpu_spec->flush_tlb = __flush_tlb_power9;
 455         cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
 456
 457         return 1;
 458 }
 459
 460 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
 461 {
 462         hfscr_pmu_enable();
 463
 464         init_pmu_power9();
 465         init_pmu_registers = init_pmu_power9;
 466
 467         cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 468         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 469
 470         cur_cpu_spec->num_pmcs          = 6;
 471         cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
 472         cur_cpu_spec->oprofile_cpu_type = "ppc64/power9";
 473
 474         return 1;
 475 }
 476
 477 static int __init feat_enable_tm(struct dt_cpu_feature *f)
 478 {
 479 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 480         feat_enable(f);
 481         cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
 482         return 1;
 483 #endif
 484         return 0;
 485 }
 486
 487 static int __init feat_enable_fp(struct dt_cpu_feature *f)
 488 {
 489         feat_enable(f);
 490         cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
 491
 492         return 1;
 493 }
 494
 495 static int __init feat_enable_vector(struct dt_cpu_feature *f)
 496 {
 497 #ifdef CONFIG_ALTIVEC
 498         feat_enable(f);
 499         cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
 500         cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
 501         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
 502
 503         return 1;
 504 #endif
 505         return 0;
 506 }
 507
 508 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
 509 {
 510 #ifdef CONFIG_VSX
 511         feat_enable(f);
 512         cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
 513         cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
 514
 515         return 1;
 516 #endif
 517         return 0;
 518 }
 519
 520 static int __init feat_enable_purr(struct dt_cpu_feature *f)
 521 {
 522         cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
 523
 524         return 1;
 525 }
 526
 527 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
 528 {
 529         /*
 530          * PPC_FEATURE2_EBB is enabled in PMU init code because it has
 531          * historically been related to the PMU facility. This may have
 532          * to be decoupled if EBB becomes more generic. For now, follow
 533          * existing convention.
 534          */
 535         f->hwcap_bit_nr = -1;
 536         feat_enable(f);
 537
 538         return 1;
 539 }
 540
 541 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
 542 {
 543         u64 lpcr;
 544
 545         /* P9 has an HFSCR for privileged state */
 546         feat_enable(f);
 547
 548         cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
 549
 550         lpcr = mfspr(SPRN_LPCR);
 551         lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
 552         mtspr(SPRN_LPCR, lpcr);
 553
 554         return 1;
 555 }
 556
 557 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
 558 {
 559         u64 lpcr;
 560
 561         /*
 562          * POWER9 XIVE interrupts including in OPAL XICS compatibility
 563          * are always delivered as hypervisor virtualization interrupts (HVI)
 564          * rather than EE.
 565          *
 566          * However LPES0 is not set here, in the chance that an EE does get
 567          * delivered to the host somehow, the EE handler would not expect it
 568          * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
 569          * happen if there is a bug in interrupt controller code, or IC is
 570          * misconfigured in systemsim.
 571          */
 572
 573         lpcr = mfspr(SPRN_LPCR);
 574         lpcr |= LPCR_HVICE;     /* enable hvi interrupts */
 575         lpcr |= LPCR_HEIC;      /* disable ee interrupts when MSR_HV */
 576         lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
 577         mtspr(SPRN_LPCR, lpcr);
 578
 579         return 1;
 580 }
 581
 582 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
 583 {
 584         cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
 585
 586         return 1;
 587 }
 588
 589 struct dt_cpu_feature_match {
 590         const char *name;
 591         int (*enable)(struct dt_cpu_feature *f);
 592         u64 cpu_ftr_bit_mask;
 593 };
 594
 595 static struct dt_cpu_feature_match __initdata
 596                 dt_cpu_feature_match_table[] = {
 597         {"hypervisor", feat_enable_hv, 0},
 598         {"big-endian", feat_enable, 0},
 599         {"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
 600         {"smt", feat_enable_smt, 0},
 601         {"interrupt-facilities", feat_enable, 0},
 602         {"timer-facilities", feat_enable, 0},
 603         {"timer-facilities-v3", feat_enable, 0},
 604         {"debug-facilities", feat_enable, 0},
 605         {"come-from-address-register", feat_enable, CPU_FTR_CFAR},
 606         {"branch-tracing", feat_enable, 0},
 607         {"floating-point", feat_enable_fp, 0},
 608         {"vector", feat_enable_vector, 0},
 609         {"vector-scalar", feat_enable_vsx, 0},
 610         {"vector-scalar-v3", feat_enable, 0},
 611         {"decimal-floating-point", feat_enable, 0},
 612         {"decimal-integer", feat_enable, 0},
 613         {"quadword-load-store", feat_enable, 0},
 614         {"vector-crypto", feat_enable, 0},
 615         {"mmu-hash", feat_enable_mmu_hash, 0},
 616         {"mmu-radix", feat_enable_mmu_radix, 0},
 617         {"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
 618         {"virtual-page-class-key-protection", feat_enable, 0},
 619         {"transactional-memory", feat_enable_tm, CPU_FTR_TM},
 620         {"transactional-memory-v3", feat_enable_tm, 0},
 621         {"idle-nap", feat_enable_idle_nap, 0},
 622         {"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
 623         {"idle-stop", feat_enable_idle_stop, 0},
 624         {"machine-check-power8", feat_enable_mce_power8, 0},
 625         {"performance-monitor-power8", feat_enable_pmu_power8, 0},
 626         {"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
 627         {"event-based-branch", feat_enable_ebb, 0},
 628         {"target-address-register", feat_enable, 0},
 629         {"branch-history-rolling-buffer", feat_enable, 0},
 630         {"control-register", feat_enable, CPU_FTR_CTRL},
 631         {"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
 632         {"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
 633         {"processor-utilization-of-resources-register", feat_enable_purr, 0},
 634         {"no-execute", feat_enable, 0},
 635         {"strong-access-ordering", feat_enable, CPU_FTR_SAO},
 636         {"cache-inhibited-large-page", feat_enable_large_ci, 0},
 637         {"coprocessor-icswx", feat_enable, CPU_FTR_ICSWX},
 638         {"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
 639         {"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
 640         {"wait", feat_enable, 0},
 641         {"atomic-memory-operations", feat_enable, 0},
 642         {"branch-v3", feat_enable, 0},
 643         {"copy-paste", feat_enable, 0},
 644         {"decimal-floating-point-v3", feat_enable, 0},
 645         {"decimal-integer-v3", feat_enable, 0},
 646         {"fixed-point-v3", feat_enable, 0},
 647         {"floating-point-v3", feat_enable, 0},
 648         {"group-start-register", feat_enable, 0},
 649         {"pc-relative-addressing", feat_enable, 0},
 650         {"machine-check-power9", feat_enable_mce_power9, 0},
 651         {"performance-monitor-power9", feat_enable_pmu_power9, 0},
 652         {"event-based-branch-v3", feat_enable, 0},
 653         {"random-number-generator", feat_enable, 0},
 654         {"system-call-vectored", feat_disable, 0},
 655         {"trace-interrupt-v3", feat_enable, 0},
 656         {"vector-v3", feat_enable, 0},
 657         {"vector-binary128", feat_enable, 0},
 658         {"vector-binary16", feat_enable, 0},
 659         {"wait-v3", feat_enable, 0},
 660 };
 661
 662 static bool __initdata using_dt_cpu_ftrs;
 663 static bool __initdata enable_unknown = true;
 664
 665 static 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 }
 679 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
 680
 681 static void __init cpufeatures_setup_start(u32 isa)
 682 {
 683         pr_info("setup for ISA %d\n", isa);
 684
 685         if (isa >= 3000) {
 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
 691 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
 692 {
 693         const struct dt_cpu_feature_match *m;
 694         bool known = false;
 695         int i;
 696
 697         for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
 698                 m = &dt_cpu_feature_match_table[i];
 699                 if (!strcmp(f->name, m->name)) {
 700                         known = true;
 701                         if (m->enable(f))
 702                                 break;
 703
 704                         pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
 705                                 f->name);
 706                         return false;
 707                 }
 708         }
 709
 710         if (!known && enable_unknown) {
 711                 if (!feat_try_enable_unknown(f)) {
 712                         pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
 713                                 f->name);
 714                         return false;
 715                 }
 716         }
 717
 718         if (m->cpu_ftr_bit_mask)
 719                 cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
 720
 721         if (known)
 722                 pr_debug("enabling: %s\n", f->name);
 723         else
 724                 pr_debug("enabling: %s (unknown)\n", f->name);
 725
 726         return true;
 727 }
 728
 729 static __init void cpufeatures_cpu_quirks(void)
 730 {
 731         int version = mfspr(SPRN_PVR);
 732
 733         /*
 734          * Not all quirks can be derived from the cpufeatures device tree.
 735          */
 736         if ((version & 0xffffff00) == 0x004e0100)
 737                 cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD1;
 738 }
 739
 740 static void __init cpufeatures_setup_finished(void)
 741 {
 742         cpufeatures_cpu_quirks();
 743
 744         if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
 745                 pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
 746                 cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 747         }
 748
 749         system_registers.lpcr = mfspr(SPRN_LPCR);
 750         system_registers.hfscr = mfspr(SPRN_HFSCR);
 751         system_registers.fscr = mfspr(SPRN_FSCR);
 752
 753         cpufeatures_flush_tlb();
 754
 755         pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
 756                 cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
 757 }
 758
 759 static int __init disabled_on_cmdline(void)
 760 {
 761         unsigned long root, chosen;
 762         const char *p;
 763
 764         root = of_get_flat_dt_root();
 765         chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
 766         if (chosen == -FDT_ERR_NOTFOUND)
 767                 return false;
 768
 769         p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
 770         if (!p)
 771                 return false;
 772
 773         if (strstr(p, "dt_cpu_ftrs=off"))
 774                 return true;
 775
 776         return false;
 777 }
 778
 779 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
 780                                         int depth, void *data)
 781 {
 782         if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
 783             && of_get_flat_dt_prop(node, "isa", NULL))
 784                 return 1;
 785
 786         return 0;
 787 }
 788
 789 bool __init dt_cpu_ftrs_in_use(void)
 790 {
 791         return using_dt_cpu_ftrs;
 792 }
 793
 794 bool __init dt_cpu_ftrs_init(void *fdt)
 795 {
 796         using_dt_cpu_ftrs = false;
 797
 798         /* Setup and verify the FDT, if it fails we just bail */
 799         if (!early_init_dt_verify(fdt))
 800                 return false;
 801
 802         if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
 803                 return false;
 804
 805         if (disabled_on_cmdline())
 806                 return false;
 807
 808         cpufeatures_setup_cpu();
 809
 810         using_dt_cpu_ftrs = true;
 811         return true;
 812 }
 813
 814 static int nr_dt_cpu_features;
 815 static struct dt_cpu_feature *dt_cpu_features;
 816
 817 static int __init process_cpufeatures_node(unsigned long node,
 818                                           const char *uname, int i)
 819 {
 820         const __be32 *prop;
 821         struct dt_cpu_feature *f;
 822         int len;
 823
 824         f = &dt_cpu_features[i];
 825         memset(f, 0, sizeof(struct dt_cpu_feature));
 826
 827         f->node = node;
 828
 829         f->name = uname;
 830
 831         prop = of_get_flat_dt_prop(node, "isa", &len);
 832         if (!prop) {
 833                 pr_warn("%s: missing isa property\n", uname);
 834                 return 0;
 835         }
 836         f->isa = be32_to_cpup(prop);
 837
 838         prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
 839         if (!prop) {
 840                 pr_warn("%s: missing usable-privilege property", uname);
 841                 return 0;
 842         }
 843         f->usable_privilege = be32_to_cpup(prop);
 844
 845         prop = of_get_flat_dt_prop(node, "hv-support", &len);
 846         if (prop)
 847                 f->hv_support = be32_to_cpup(prop);
 848         else
 849                 f->hv_support = HV_SUPPORT_NONE;
 850
 851         prop = of_get_flat_dt_prop(node, "os-support", &len);
 852         if (prop)
 853                 f->os_support = be32_to_cpup(prop);
 854         else
 855                 f->os_support = OS_SUPPORT_NONE;
 856
 857         prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
 858         if (prop)
 859                 f->hfscr_bit_nr = be32_to_cpup(prop);
 860         else
 861                 f->hfscr_bit_nr = -1;
 862         prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
 863         if (prop)
 864                 f->fscr_bit_nr = be32_to_cpup(prop);
 865         else
 866                 f->fscr_bit_nr = -1;
 867         prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
 868         if (prop)
 869                 f->hwcap_bit_nr = be32_to_cpup(prop);
 870         else
 871                 f->hwcap_bit_nr = -1;
 872
 873         if (f->usable_privilege & USABLE_HV) {
 874                 if (!(mfmsr() & MSR_HV)) {
 875                         pr_warn("%s: HV feature passed to guest\n", uname);
 876                         return 0;
 877                 }
 878
 879                 if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
 880                         pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
 881                         return 0;
 882                 }
 883
 884                 if (f->hv_support == HV_SUPPORT_HFSCR) {
 885                         if (f->hfscr_bit_nr == -1) {
 886                                 pr_warn("%s: missing hfscr_bit_nr\n", uname);
 887                                 return 0;
 888                         }
 889                 }
 890         } else {
 891                 if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
 892                         pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
 893                         return 0;
 894                 }
 895         }
 896
 897         if (f->usable_privilege & USABLE_OS) {
 898                 if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
 899                         pr_warn("%s: unwanted fscr_bit_nr\n", uname);
 900                         return 0;
 901                 }
 902
 903                 if (f->os_support == OS_SUPPORT_FSCR) {
 904                         if (f->fscr_bit_nr == -1) {
 905                                 pr_warn("%s: missing fscr_bit_nr\n", uname);
 906                                 return 0;
 907                         }
 908                 }
 909         } else {
 910                 if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
 911                         pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
 912                         return 0;
 913                 }
 914         }
 915
 916         if (!(f->usable_privilege & USABLE_PR)) {
 917                 if (f->hwcap_bit_nr != -1) {
 918                         pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
 919                         return 0;
 920                 }
 921         }
 922
 923         /* Do all the independent features in the first pass */
 924         if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
 925                 if (cpufeatures_process_feature(f))
 926                         f->enabled = 1;
 927                 else
 928                         f->disabled = 1;
 929         }
 930
 931         return 0;
 932 }
 933
 934 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
 935 {
 936         const __be32 *prop;
 937         int len;
 938         int nr_deps;
 939         int i;
 940
 941         if (f->enabled || f->disabled)
 942                 return;
 943
 944         prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
 945         if (!prop) {
 946                 pr_warn("%s: missing dependencies property", f->name);
 947                 return;
 948         }
 949
 950         nr_deps = len / sizeof(int);
 951
 952         for (i = 0; i < nr_deps; i++) {
 953                 unsigned long phandle = be32_to_cpu(prop[i]);
 954                 int j;
 955
 956                 for (j = 0; j < nr_dt_cpu_features; j++) {
 957                         struct dt_cpu_feature *d = &dt_cpu_features[j];
 958
 959                         if (of_get_flat_dt_phandle(d->node) == phandle) {
 960                                 cpufeatures_deps_enable(d);
 961                                 if (d->disabled) {
 962                                         f->disabled = 1;
 963                                         return;
 964                                 }
 965                         }
 966                 }
 967         }
 968
 969         if (cpufeatures_process_feature(f))
 970                 f->enabled = 1;
 971         else
 972                 f->disabled = 1;
 973 }
 974
 975 static int __init scan_cpufeatures_subnodes(unsigned long node,
 976                                           const char *uname,
 977                                           void *data)
 978 {
 979         int *count = data;
 980
 981         process_cpufeatures_node(node, uname, *count);
 982
 983         (*count)++;
 984
 985         return 0;
 986 }
 987
 988 static int __init count_cpufeatures_subnodes(unsigned long node,
 989                                           const char *uname,
 990                                           void *data)
 991 {
 992         int *count = data;
 993
 994         (*count)++;
 995
 996         return 0;
 997 }
 998
 999 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1000                                             *uname, int depth, void *data)
1001 {
1002         const __be32 *prop;
1003         int count, i;
1004         u32 isa;
1005
1006         /* We are scanning "ibm,powerpc-cpu-features" nodes only */
1007         if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1008                 return 0;
1009
1010         prop = of_get_flat_dt_prop(node, "isa", NULL);
1011         if (!prop)
1012                 /* We checked before, "can't happen" */
1013                 return 0;
1014
1015         isa = be32_to_cpup(prop);
1016
1017         /* Count and allocate space for cpu features */
1018         of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1019                                                 &nr_dt_cpu_features);
1020         dt_cpu_features = __va(
1021                 memblock_alloc(sizeof(struct dt_cpu_feature)*
1022                                 nr_dt_cpu_features, PAGE_SIZE));
1023
1024         cpufeatures_setup_start(isa);
1025
1026         /* Scan nodes into dt_cpu_features and enable those without deps  */
1027         count = 0;
1028         of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1029
1030         /* Recursive enable remaining features with dependencies */
1031         for (i = 0; i < nr_dt_cpu_features; i++) {
1032                 struct dt_cpu_feature *f = &dt_cpu_features[i];
1033
1034                 cpufeatures_deps_enable(f);
1035         }
1036
1037         prop = of_get_flat_dt_prop(node, "display-name", NULL);
1038         if (prop && strlen((char *)prop) != 0) {
1039                 strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1040                 cur_cpu_spec->cpu_name = dt_cpu_name;
1041         }
1042
1043         cpufeatures_setup_finished();
1044
1045         memblock_free(__pa(dt_cpu_features),
1046                         sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1047
1048         return 0;
1049 }
1050
1051 void __init dt_cpu_ftrs_scan(void)
1052 {
1053         if (!using_dt_cpu_ftrs)
1054                 return;
1055
1056         of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1057 }