Linux Audio

Check our new training course

Loading...
v4.17
 
   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
  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
  67extern long __machine_check_early_realmode_p8(struct pt_regs *regs);
  68extern long __machine_check_early_realmode_p9(struct pt_regs *regs);
  69
  70static int hv_mode;
  71
  72static struct {
  73	u64	lpcr;
  74	u64	lpcr_clear;
  75	u64	hfscr;
  76	u64	fscr;
  77} system_registers;
  78
  79static void (*init_pmu_registers)(void);
  80
  81static void __restore_cpu_cpufeatures(void)
  82{
  83	u64 lpcr;
  84
  85	/*
  86	 * LPCR is restored by the power on engine already. It can be changed
  87	 * after early init e.g., by radix enable, and we have no unified API
  88	 * for saving and restoring such SPRs.
  89	 *
  90	 * This ->restore hook should really be removed from idle and register
  91	 * restore moved directly into the idle restore code, because this code
  92	 * doesn't know how idle is implemented or what it needs restored here.
  93	 *
  94	 * The best we can do to accommodate secondary boot and idle restore
  95	 * for now is "or" LPCR with existing.
  96	 */
  97	lpcr = mfspr(SPRN_LPCR);
  98	lpcr |= system_registers.lpcr;
  99	lpcr &= ~system_registers.lpcr_clear;
 100	mtspr(SPRN_LPCR, lpcr);
 101	if (hv_mode) {
 102		mtspr(SPRN_LPID, 0);
 103		mtspr(SPRN_HFSCR, system_registers.hfscr);
 104		mtspr(SPRN_PCR, 0);
 105	}
 106	mtspr(SPRN_FSCR, system_registers.fscr);
 107
 108	if (init_pmu_registers)
 109		init_pmu_registers();
 110}
 111
 112static char dt_cpu_name[64];
 113
 114static struct cpu_spec __initdata base_cpu_spec = {
 115	.cpu_name		= NULL,
 116	.cpu_features		= CPU_FTRS_DT_CPU_BASE,
 117	.cpu_user_features	= COMMON_USER_BASE,
 118	.cpu_user_features2	= COMMON_USER2_BASE,
 119	.mmu_features		= 0,
 120	.icache_bsize		= 32, /* minimum block size, fixed by */
 121	.dcache_bsize		= 32, /* cache info init.             */
 122	.num_pmcs		= 0,
 123	.pmc_type		= PPC_PMC_DEFAULT,
 124	.oprofile_cpu_type	= NULL,
 125	.oprofile_type		= PPC_OPROFILE_INVALID,
 126	.cpu_setup		= NULL,
 127	.cpu_restore		= __restore_cpu_cpufeatures,
 128	.machine_check_early	= NULL,
 129	.platform		= NULL,
 130};
 131
 132static void __init cpufeatures_setup_cpu(void)
 133{
 134	set_cur_cpu_spec(&base_cpu_spec);
 135
 136	cur_cpu_spec->pvr_mask = -1;
 137	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
 138
 139	/* Initialize the base environment -- clear FSCR/HFSCR.  */
 140	hv_mode = !!(mfmsr() & MSR_HV);
 141	if (hv_mode) {
 142		/* CPU_FTR_HVMODE is used early in PACA setup */
 143		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 144		mtspr(SPRN_HFSCR, 0);
 145	}
 146	mtspr(SPRN_FSCR, 0);
 
 147
 148	/*
 149	 * LPCR does not get cleared, to match behaviour with secondaries
 150	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
 151	 * could clear LPCR too.
 152	 */
 153}
 154
 155static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
 156{
 157	if (f->hv_support == HV_SUPPORT_NONE) {
 158	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
 159		u64 hfscr = mfspr(SPRN_HFSCR);
 160		hfscr |= 1UL << f->hfscr_bit_nr;
 161		mtspr(SPRN_HFSCR, hfscr);
 162	} else {
 163		/* Does not have a known recipe */
 164		return 0;
 165	}
 166
 167	if (f->os_support == OS_SUPPORT_NONE) {
 168	} else if (f->os_support & OS_SUPPORT_FSCR) {
 169		u64 fscr = mfspr(SPRN_FSCR);
 170		fscr |= 1UL << f->fscr_bit_nr;
 171		mtspr(SPRN_FSCR, fscr);
 172	} else {
 173		/* Does not have a known recipe */
 174		return 0;
 175	}
 176
 177	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 178		uint32_t word = f->hwcap_bit_nr / 32;
 179		uint32_t bit = f->hwcap_bit_nr % 32;
 180
 181		if (word == 0)
 182			cur_cpu_spec->cpu_user_features |= 1U << bit;
 183		else if (word == 1)
 184			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 185		else
 186			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
 187	}
 188
 189	return 1;
 190}
 191
 192static int __init feat_enable(struct dt_cpu_feature *f)
 193{
 194	if (f->hv_support != HV_SUPPORT_NONE) {
 195		if (f->hfscr_bit_nr != -1) {
 196			u64 hfscr = mfspr(SPRN_HFSCR);
 197			hfscr |= 1UL << f->hfscr_bit_nr;
 198			mtspr(SPRN_HFSCR, hfscr);
 199		}
 200	}
 201
 202	if (f->os_support != OS_SUPPORT_NONE) {
 203		if (f->fscr_bit_nr != -1) {
 204			u64 fscr = mfspr(SPRN_FSCR);
 205			fscr |= 1UL << f->fscr_bit_nr;
 206			mtspr(SPRN_FSCR, fscr);
 207		}
 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("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
 220	}
 221
 222	return 1;
 223}
 224
 225static int __init feat_disable(struct dt_cpu_feature *f)
 226{
 227	return 0;
 228}
 229
 230static int __init feat_enable_hv(struct dt_cpu_feature *f)
 231{
 232	u64 lpcr;
 233
 234	if (!hv_mode) {
 235		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
 236		return 0;
 237	}
 238
 239	mtspr(SPRN_LPID, 0);
 240
 241	lpcr = mfspr(SPRN_LPCR);
 242	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
 243	mtspr(SPRN_LPCR, lpcr);
 244
 245	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 246
 247	return 1;
 248}
 249
 250static int __init feat_enable_le(struct dt_cpu_feature *f)
 251{
 252	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
 253	return 1;
 254}
 255
 256static int __init feat_enable_smt(struct dt_cpu_feature *f)
 257{
 258	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 259	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
 260	return 1;
 261}
 262
 263static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
 264{
 265	u64 lpcr;
 266
 267	/* Set PECE wakeup modes for ISA 207 */
 268	lpcr = mfspr(SPRN_LPCR);
 269	lpcr |=  LPCR_PECE0;
 270	lpcr |=  LPCR_PECE1;
 271	lpcr |=  LPCR_PECE2;
 272	mtspr(SPRN_LPCR, lpcr);
 273
 274	return 1;
 275}
 276
 277static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
 278{
 279	cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
 280
 281	return 1;
 282}
 283
 284static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
 285{
 286	u64 lpcr;
 287
 288	/* Set PECE wakeup modes for ISAv3.0B */
 289	lpcr = mfspr(SPRN_LPCR);
 290	lpcr |=  LPCR_PECE0;
 291	lpcr |=  LPCR_PECE1;
 292	lpcr |=  LPCR_PECE2;
 293	mtspr(SPRN_LPCR, lpcr);
 294
 295	return 1;
 296}
 297
 298static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
 299{
 300	u64 lpcr;
 301
 302	lpcr = mfspr(SPRN_LPCR);
 303	lpcr &= ~LPCR_ISL;
 304
 305	/* VRMASD */
 306	lpcr |= LPCR_VPM0;
 307	lpcr &= ~LPCR_VPM1;
 308	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
 309	mtspr(SPRN_LPCR, lpcr);
 310
 311	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 312	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 313
 314	return 1;
 315}
 316
 317static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
 318{
 319	u64 lpcr;
 320
 321	system_registers.lpcr_clear |= (LPCR_ISL | LPCR_UPRT | LPCR_HR);
 322	lpcr = mfspr(SPRN_LPCR);
 323	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
 324	mtspr(SPRN_LPCR, lpcr);
 325
 326	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 327	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 328
 329	return 1;
 330}
 331
 332
 333static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
 334{
 335#ifdef CONFIG_PPC_RADIX_MMU
 336	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
 337	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 338	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 339
 340	return 1;
 341#endif
 342	return 0;
 343}
 344
 345static int __init feat_enable_dscr(struct dt_cpu_feature *f)
 346{
 347	u64 lpcr;
 348
 349	feat_enable(f);
 350
 351	lpcr = mfspr(SPRN_LPCR);
 352	lpcr &= ~LPCR_DPFD;
 353	lpcr |=  (4UL << LPCR_DPFD_SH);
 354	mtspr(SPRN_LPCR, lpcr);
 355
 356	return 1;
 357}
 358
 359static void hfscr_pmu_enable(void)
 360{
 361	u64 hfscr = mfspr(SPRN_HFSCR);
 362	hfscr |= PPC_BIT(60);
 363	mtspr(SPRN_HFSCR, hfscr);
 364}
 365
 366static void init_pmu_power8(void)
 367{
 368	if (hv_mode) {
 369		mtspr(SPRN_MMCRC, 0);
 370		mtspr(SPRN_MMCRH, 0);
 371	}
 372
 373	mtspr(SPRN_MMCRA, 0);
 374	mtspr(SPRN_MMCR0, 0);
 375	mtspr(SPRN_MMCR1, 0);
 376	mtspr(SPRN_MMCR2, 0);
 377	mtspr(SPRN_MMCRS, 0);
 378}
 379
 380static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
 381{
 382	cur_cpu_spec->platform = "power8";
 383	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
 384
 385	return 1;
 386}
 387
 388static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
 389{
 390	hfscr_pmu_enable();
 391
 392	init_pmu_power8();
 393	init_pmu_registers = init_pmu_power8;
 394
 395	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 396	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 397	if (pvr_version_is(PVR_POWER8E))
 398		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
 399
 400	cur_cpu_spec->num_pmcs		= 6;
 401	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
 402	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
 403
 404	return 1;
 405}
 406
 407static void init_pmu_power9(void)
 408{
 409	if (hv_mode)
 410		mtspr(SPRN_MMCRC, 0);
 411
 412	mtspr(SPRN_MMCRA, 0);
 413	mtspr(SPRN_MMCR0, 0);
 414	mtspr(SPRN_MMCR1, 0);
 415	mtspr(SPRN_MMCR2, 0);
 416}
 417
 418static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
 419{
 420	cur_cpu_spec->platform = "power9";
 421	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
 422
 423	return 1;
 424}
 425
 426static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
 427{
 428	hfscr_pmu_enable();
 429
 430	init_pmu_power9();
 431	init_pmu_registers = init_pmu_power9;
 432
 433	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 434	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 435
 436	cur_cpu_spec->num_pmcs		= 6;
 437	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
 438	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
 439
 440	return 1;
 441}
 442
 443static int __init feat_enable_tm(struct dt_cpu_feature *f)
 444{
 445#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 446	feat_enable(f);
 447	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
 448	return 1;
 449#endif
 450	return 0;
 451}
 452
 453static int __init feat_enable_fp(struct dt_cpu_feature *f)
 454{
 455	feat_enable(f);
 456	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
 457
 458	return 1;
 459}
 460
 461static int __init feat_enable_vector(struct dt_cpu_feature *f)
 462{
 463#ifdef CONFIG_ALTIVEC
 464	feat_enable(f);
 465	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
 466	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
 467	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
 468
 469	return 1;
 470#endif
 471	return 0;
 472}
 473
 474static int __init feat_enable_vsx(struct dt_cpu_feature *f)
 475{
 476#ifdef CONFIG_VSX
 477	feat_enable(f);
 478	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
 479	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
 480
 481	return 1;
 482#endif
 483	return 0;
 484}
 485
 486static int __init feat_enable_purr(struct dt_cpu_feature *f)
 487{
 488	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
 489
 490	return 1;
 491}
 492
 493static int __init feat_enable_ebb(struct dt_cpu_feature *f)
 494{
 495	/*
 496	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
 497	 * historically been related to the PMU facility. This may have
 498	 * to be decoupled if EBB becomes more generic. For now, follow
 499	 * existing convention.
 500	 */
 501	f->hwcap_bit_nr = -1;
 502	feat_enable(f);
 503
 504	return 1;
 505}
 506
 507static int __init feat_enable_dbell(struct dt_cpu_feature *f)
 508{
 509	u64 lpcr;
 510
 511	/* P9 has an HFSCR for privileged state */
 512	feat_enable(f);
 513
 514	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
 515
 516	lpcr = mfspr(SPRN_LPCR);
 517	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
 518	mtspr(SPRN_LPCR, lpcr);
 519
 520	return 1;
 521}
 522
 523static int __init feat_enable_hvi(struct dt_cpu_feature *f)
 524{
 525	u64 lpcr;
 526
 527	/*
 528	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
 529	 * are always delivered as hypervisor virtualization interrupts (HVI)
 530	 * rather than EE.
 531	 *
 532	 * However LPES0 is not set here, in the chance that an EE does get
 533	 * delivered to the host somehow, the EE handler would not expect it
 534	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
 535	 * happen if there is a bug in interrupt controller code, or IC is
 536	 * misconfigured in systemsim.
 537	 */
 538
 539	lpcr = mfspr(SPRN_LPCR);
 540	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
 541	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
 542	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
 543	mtspr(SPRN_LPCR, lpcr);
 544
 545	return 1;
 546}
 547
 548static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
 549{
 550	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
 551
 552	return 1;
 553}
 554
 555struct dt_cpu_feature_match {
 556	const char *name;
 557	int (*enable)(struct dt_cpu_feature *f);
 558	u64 cpu_ftr_bit_mask;
 559};
 560
 561static struct dt_cpu_feature_match __initdata
 562		dt_cpu_feature_match_table[] = {
 563	{"hypervisor", feat_enable_hv, 0},
 564	{"big-endian", feat_enable, 0},
 565	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
 566	{"smt", feat_enable_smt, 0},
 567	{"interrupt-facilities", feat_enable, 0},
 568	{"timer-facilities", feat_enable, 0},
 569	{"timer-facilities-v3", feat_enable, 0},
 570	{"debug-facilities", feat_enable, 0},
 571	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
 572	{"branch-tracing", feat_enable, 0},
 573	{"floating-point", feat_enable_fp, 0},
 574	{"vector", feat_enable_vector, 0},
 575	{"vector-scalar", feat_enable_vsx, 0},
 576	{"vector-scalar-v3", feat_enable, 0},
 577	{"decimal-floating-point", feat_enable, 0},
 578	{"decimal-integer", feat_enable, 0},
 579	{"quadword-load-store", feat_enable, 0},
 580	{"vector-crypto", feat_enable, 0},
 581	{"mmu-hash", feat_enable_mmu_hash, 0},
 582	{"mmu-radix", feat_enable_mmu_radix, 0},
 583	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
 584	{"virtual-page-class-key-protection", feat_enable, 0},
 585	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
 586	{"transactional-memory-v3", feat_enable_tm, 0},
 587	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
 588	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
 589	{"idle-nap", feat_enable_idle_nap, 0},
 590	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
 591	{"idle-stop", feat_enable_idle_stop, 0},
 592	{"machine-check-power8", feat_enable_mce_power8, 0},
 593	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
 594	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
 595	{"event-based-branch", feat_enable_ebb, 0},
 596	{"target-address-register", feat_enable, 0},
 597	{"branch-history-rolling-buffer", feat_enable, 0},
 598	{"control-register", feat_enable, CPU_FTR_CTRL},
 599	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
 600	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
 601	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
 602	{"no-execute", feat_enable, 0},
 603	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
 604	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
 605	{"coprocessor-icswx", feat_enable, 0},
 606	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
 607	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
 608	{"wait", feat_enable, 0},
 609	{"atomic-memory-operations", feat_enable, 0},
 610	{"branch-v3", feat_enable, 0},
 611	{"copy-paste", feat_enable, 0},
 612	{"decimal-floating-point-v3", feat_enable, 0},
 613	{"decimal-integer-v3", feat_enable, 0},
 614	{"fixed-point-v3", feat_enable, 0},
 615	{"floating-point-v3", feat_enable, 0},
 616	{"group-start-register", feat_enable, 0},
 617	{"pc-relative-addressing", feat_enable, 0},
 618	{"machine-check-power9", feat_enable_mce_power9, 0},
 619	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
 620	{"event-based-branch-v3", feat_enable, 0},
 621	{"random-number-generator", feat_enable, 0},
 622	{"system-call-vectored", feat_disable, 0},
 623	{"trace-interrupt-v3", feat_enable, 0},
 624	{"vector-v3", feat_enable, 0},
 625	{"vector-binary128", feat_enable, 0},
 626	{"vector-binary16", feat_enable, 0},
 627	{"wait-v3", feat_enable, 0},
 628};
 629
 630static bool __initdata using_dt_cpu_ftrs;
 631static bool __initdata enable_unknown = true;
 632
 633static int __init dt_cpu_ftrs_parse(char *str)
 634{
 635	if (!str)
 636		return 0;
 637
 638	if (!strcmp(str, "off"))
 639		using_dt_cpu_ftrs = false;
 640	else if (!strcmp(str, "known"))
 641		enable_unknown = false;
 642	else
 643		return 1;
 644
 645	return 0;
 646}
 647early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
 648
 649static void __init cpufeatures_setup_start(u32 isa)
 650{
 651	pr_info("setup for ISA %d\n", isa);
 652
 653	if (isa >= 3000) {
 654		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
 655		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
 656	}
 657}
 658
 659static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
 660{
 661	const struct dt_cpu_feature_match *m;
 662	bool known = false;
 663	int i;
 664
 665	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
 666		m = &dt_cpu_feature_match_table[i];
 667		if (!strcmp(f->name, m->name)) {
 668			known = true;
 669			if (m->enable(f))
 
 670				break;
 
 671
 672			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
 673				f->name);
 674			return false;
 675		}
 676	}
 677
 678	if (!known && enable_unknown) {
 679		if (!feat_try_enable_unknown(f)) {
 680			pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
 681				f->name);
 682			return false;
 683		}
 684	}
 685
 686	if (m->cpu_ftr_bit_mask)
 687		cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
 688
 689	if (known)
 690		pr_debug("enabling: %s\n", f->name);
 691	else
 692		pr_debug("enabling: %s (unknown)\n", f->name);
 693
 694	return true;
 695}
 696
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 697static __init void cpufeatures_cpu_quirks(void)
 698{
 699	int version = mfspr(SPRN_PVR);
 700
 701	/*
 702	 * Not all quirks can be derived from the cpufeatures device tree.
 703	 */
 704	if ((version & 0xffffff00) == 0x004e0100)
 705		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD1;
 706	else if ((version & 0xffffefff) == 0x004e0200)
 707		; /* DD2.0 has no feature flag */
 708	else if ((version & 0xffffefff) == 0x004e0201)
 709		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 710	else if ((version & 0xffffefff) == 0x004e0202) {
 711		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
 712		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
 713		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 714	} else /* DD2.1 and up have DD2_1 */
 
 715		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 716
 717	if ((version & 0xffff0000) == 0x004e0000) {
 718		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
 719		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_BUG;
 720	}
 721
 
 722	/*
 723	 * PKEY was not in the initial base or feature node
 724	 * specification, but it should become optional in the next
 725	 * cpu feature version sequence.
 726	 */
 727	cur_cpu_spec->cpu_features |= CPU_FTR_PKEY;
 728}
 729
 730static void __init cpufeatures_setup_finished(void)
 731{
 732	cpufeatures_cpu_quirks();
 733
 734	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
 735		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
 736		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 737	}
 738
 739	/* Make sure powerpc_base_platform is non-NULL */
 740	powerpc_base_platform = cur_cpu_spec->platform;
 741
 742	system_registers.lpcr = mfspr(SPRN_LPCR);
 743	system_registers.hfscr = mfspr(SPRN_HFSCR);
 744	system_registers.fscr = mfspr(SPRN_FSCR);
 745
 746	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
 747		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
 748}
 749
 750static int __init disabled_on_cmdline(void)
 751{
 752	unsigned long root, chosen;
 753	const char *p;
 754
 755	root = of_get_flat_dt_root();
 756	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
 757	if (chosen == -FDT_ERR_NOTFOUND)
 758		return false;
 759
 760	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
 761	if (!p)
 762		return false;
 763
 764	if (strstr(p, "dt_cpu_ftrs=off"))
 765		return true;
 766
 767	return false;
 768}
 769
 770static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
 771					int depth, void *data)
 772{
 773	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
 774	    && of_get_flat_dt_prop(node, "isa", NULL))
 775		return 1;
 776
 777	return 0;
 778}
 779
 780bool __init dt_cpu_ftrs_in_use(void)
 781{
 782	return using_dt_cpu_ftrs;
 783}
 784
 785bool __init dt_cpu_ftrs_init(void *fdt)
 786{
 787	using_dt_cpu_ftrs = false;
 788
 789	/* Setup and verify the FDT, if it fails we just bail */
 790	if (!early_init_dt_verify(fdt))
 791		return false;
 792
 793	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
 794		return false;
 795
 796	if (disabled_on_cmdline())
 797		return false;
 798
 799	cpufeatures_setup_cpu();
 800
 801	using_dt_cpu_ftrs = true;
 802	return true;
 803}
 804
 805static int nr_dt_cpu_features;
 806static struct dt_cpu_feature *dt_cpu_features;
 807
 808static int __init process_cpufeatures_node(unsigned long node,
 809					  const char *uname, int i)
 810{
 811	const __be32 *prop;
 812	struct dt_cpu_feature *f;
 813	int len;
 814
 815	f = &dt_cpu_features[i];
 816	memset(f, 0, sizeof(struct dt_cpu_feature));
 817
 818	f->node = node;
 819
 820	f->name = uname;
 821
 822	prop = of_get_flat_dt_prop(node, "isa", &len);
 823	if (!prop) {
 824		pr_warn("%s: missing isa property\n", uname);
 825		return 0;
 826	}
 827	f->isa = be32_to_cpup(prop);
 828
 829	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
 830	if (!prop) {
 831		pr_warn("%s: missing usable-privilege property", uname);
 832		return 0;
 833	}
 834	f->usable_privilege = be32_to_cpup(prop);
 835
 836	prop = of_get_flat_dt_prop(node, "hv-support", &len);
 837	if (prop)
 838		f->hv_support = be32_to_cpup(prop);
 839	else
 840		f->hv_support = HV_SUPPORT_NONE;
 841
 842	prop = of_get_flat_dt_prop(node, "os-support", &len);
 843	if (prop)
 844		f->os_support = be32_to_cpup(prop);
 845	else
 846		f->os_support = OS_SUPPORT_NONE;
 847
 848	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
 849	if (prop)
 850		f->hfscr_bit_nr = be32_to_cpup(prop);
 851	else
 852		f->hfscr_bit_nr = -1;
 853	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
 854	if (prop)
 855		f->fscr_bit_nr = be32_to_cpup(prop);
 856	else
 857		f->fscr_bit_nr = -1;
 858	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
 859	if (prop)
 860		f->hwcap_bit_nr = be32_to_cpup(prop);
 861	else
 862		f->hwcap_bit_nr = -1;
 863
 864	if (f->usable_privilege & USABLE_HV) {
 865		if (!(mfmsr() & MSR_HV)) {
 866			pr_warn("%s: HV feature passed to guest\n", uname);
 867			return 0;
 868		}
 869
 870		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
 871			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
 872			return 0;
 873		}
 874
 875		if (f->hv_support == HV_SUPPORT_HFSCR) {
 876			if (f->hfscr_bit_nr == -1) {
 877				pr_warn("%s: missing hfscr_bit_nr\n", uname);
 878				return 0;
 879			}
 880		}
 881	} else {
 882		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
 883			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
 884			return 0;
 885		}
 886	}
 887
 888	if (f->usable_privilege & USABLE_OS) {
 889		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
 890			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
 891			return 0;
 892		}
 893
 894		if (f->os_support == OS_SUPPORT_FSCR) {
 895			if (f->fscr_bit_nr == -1) {
 896				pr_warn("%s: missing fscr_bit_nr\n", uname);
 897				return 0;
 898			}
 899		}
 900	} else {
 901		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
 902			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
 903			return 0;
 904		}
 905	}
 906
 907	if (!(f->usable_privilege & USABLE_PR)) {
 908		if (f->hwcap_bit_nr != -1) {
 909			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
 910			return 0;
 911		}
 912	}
 913
 914	/* Do all the independent features in the first pass */
 915	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
 916		if (cpufeatures_process_feature(f))
 917			f->enabled = 1;
 918		else
 919			f->disabled = 1;
 920	}
 921
 922	return 0;
 923}
 924
 925static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
 926{
 927	const __be32 *prop;
 928	int len;
 929	int nr_deps;
 930	int i;
 931
 932	if (f->enabled || f->disabled)
 933		return;
 934
 935	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
 936	if (!prop) {
 937		pr_warn("%s: missing dependencies property", f->name);
 938		return;
 939	}
 940
 941	nr_deps = len / sizeof(int);
 942
 943	for (i = 0; i < nr_deps; i++) {
 944		unsigned long phandle = be32_to_cpu(prop[i]);
 945		int j;
 946
 947		for (j = 0; j < nr_dt_cpu_features; j++) {
 948			struct dt_cpu_feature *d = &dt_cpu_features[j];
 949
 950			if (of_get_flat_dt_phandle(d->node) == phandle) {
 951				cpufeatures_deps_enable(d);
 952				if (d->disabled) {
 953					f->disabled = 1;
 954					return;
 955				}
 956			}
 957		}
 958	}
 959
 960	if (cpufeatures_process_feature(f))
 961		f->enabled = 1;
 962	else
 963		f->disabled = 1;
 964}
 965
 966static int __init scan_cpufeatures_subnodes(unsigned long node,
 967					  const char *uname,
 968					  void *data)
 969{
 970	int *count = data;
 971
 972	process_cpufeatures_node(node, uname, *count);
 973
 974	(*count)++;
 975
 976	return 0;
 977}
 978
 979static int __init count_cpufeatures_subnodes(unsigned long node,
 980					  const char *uname,
 981					  void *data)
 982{
 983	int *count = data;
 984
 985	(*count)++;
 986
 987	return 0;
 988}
 989
 990static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
 991					    *uname, int depth, void *data)
 992{
 993	const __be32 *prop;
 994	int count, i;
 995	u32 isa;
 996
 997	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
 998	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
 999		return 0;
1000
1001	prop = of_get_flat_dt_prop(node, "isa", NULL);
1002	if (!prop)
1003		/* We checked before, "can't happen" */
1004		return 0;
1005
1006	isa = be32_to_cpup(prop);
1007
1008	/* Count and allocate space for cpu features */
1009	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1010						&nr_dt_cpu_features);
1011	dt_cpu_features = __va(
1012		memblock_alloc(sizeof(struct dt_cpu_feature)*
1013				nr_dt_cpu_features, PAGE_SIZE));
 
 
 
1014
1015	cpufeatures_setup_start(isa);
1016
1017	/* Scan nodes into dt_cpu_features and enable those without deps  */
1018	count = 0;
1019	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1020
1021	/* Recursive enable remaining features with dependencies */
1022	for (i = 0; i < nr_dt_cpu_features; i++) {
1023		struct dt_cpu_feature *f = &dt_cpu_features[i];
1024
1025		cpufeatures_deps_enable(f);
1026	}
1027
1028	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1029	if (prop && strlen((char *)prop) != 0) {
1030		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1031		cur_cpu_spec->cpu_name = dt_cpu_name;
1032	}
1033
1034	cpufeatures_setup_finished();
1035
1036	memblock_free(__pa(dt_cpu_features),
1037			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1038
1039	return 0;
1040}
1041
1042void __init dt_cpu_ftrs_scan(void)
1043{
1044	if (!using_dt_cpu_ftrs)
1045		return;
1046
1047	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1048}
v5.4
   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_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
  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
  67extern long __machine_check_early_realmode_p8(struct pt_regs *regs);
  68extern long __machine_check_early_realmode_p9(struct pt_regs *regs);
  69
  70static int hv_mode;
  71
  72static struct {
  73	u64	lpcr;
  74	u64	lpcr_clear;
  75	u64	hfscr;
  76	u64	fscr;
  77} system_registers;
  78
  79static void (*init_pmu_registers)(void);
  80
  81static void __restore_cpu_cpufeatures(void)
  82{
  83	u64 lpcr;
  84
  85	/*
  86	 * LPCR is restored by the power on engine already. It can be changed
  87	 * after early init e.g., by radix enable, and we have no unified API
  88	 * for saving and restoring such SPRs.
  89	 *
  90	 * This ->restore hook should really be removed from idle and register
  91	 * restore moved directly into the idle restore code, because this code
  92	 * doesn't know how idle is implemented or what it needs restored here.
  93	 *
  94	 * The best we can do to accommodate secondary boot and idle restore
  95	 * for now is "or" LPCR with existing.
  96	 */
  97	lpcr = mfspr(SPRN_LPCR);
  98	lpcr |= system_registers.lpcr;
  99	lpcr &= ~system_registers.lpcr_clear;
 100	mtspr(SPRN_LPCR, lpcr);
 101	if (hv_mode) {
 102		mtspr(SPRN_LPID, 0);
 103		mtspr(SPRN_HFSCR, system_registers.hfscr);
 104		mtspr(SPRN_PCR, PCR_MASK);
 105	}
 106	mtspr(SPRN_FSCR, system_registers.fscr);
 107
 108	if (init_pmu_registers)
 109		init_pmu_registers();
 110}
 111
 112static char dt_cpu_name[64];
 113
 114static struct cpu_spec __initdata base_cpu_spec = {
 115	.cpu_name		= NULL,
 116	.cpu_features		= CPU_FTRS_DT_CPU_BASE,
 117	.cpu_user_features	= COMMON_USER_BASE,
 118	.cpu_user_features2	= COMMON_USER2_BASE,
 119	.mmu_features		= 0,
 120	.icache_bsize		= 32, /* minimum block size, fixed by */
 121	.dcache_bsize		= 32, /* cache info init.             */
 122	.num_pmcs		= 0,
 123	.pmc_type		= PPC_PMC_DEFAULT,
 124	.oprofile_cpu_type	= NULL,
 125	.oprofile_type		= PPC_OPROFILE_INVALID,
 126	.cpu_setup		= NULL,
 127	.cpu_restore		= __restore_cpu_cpufeatures,
 128	.machine_check_early	= NULL,
 129	.platform		= NULL,
 130};
 131
 132static void __init cpufeatures_setup_cpu(void)
 133{
 134	set_cur_cpu_spec(&base_cpu_spec);
 135
 136	cur_cpu_spec->pvr_mask = -1;
 137	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
 138
 139	/* Initialize the base environment -- clear FSCR/HFSCR.  */
 140	hv_mode = !!(mfmsr() & MSR_HV);
 141	if (hv_mode) {
 142		/* CPU_FTR_HVMODE is used early in PACA setup */
 143		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 144		mtspr(SPRN_HFSCR, 0);
 145	}
 146	mtspr(SPRN_FSCR, 0);
 147	mtspr(SPRN_PCR, PCR_MASK);
 148
 149	/*
 150	 * LPCR does not get cleared, to match behaviour with secondaries
 151	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
 152	 * could clear LPCR too.
 153	 */
 154}
 155
 156static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
 157{
 158	if (f->hv_support == HV_SUPPORT_NONE) {
 159	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
 160		u64 hfscr = mfspr(SPRN_HFSCR);
 161		hfscr |= 1UL << f->hfscr_bit_nr;
 162		mtspr(SPRN_HFSCR, hfscr);
 163	} else {
 164		/* Does not have a known recipe */
 165		return 0;
 166	}
 167
 168	if (f->os_support == OS_SUPPORT_NONE) {
 169	} else if (f->os_support & OS_SUPPORT_FSCR) {
 170		u64 fscr = mfspr(SPRN_FSCR);
 171		fscr |= 1UL << f->fscr_bit_nr;
 172		mtspr(SPRN_FSCR, fscr);
 173	} else {
 174		/* Does not have a known recipe */
 175		return 0;
 176	}
 177
 178	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 179		uint32_t word = f->hwcap_bit_nr / 32;
 180		uint32_t bit = f->hwcap_bit_nr % 32;
 181
 182		if (word == 0)
 183			cur_cpu_spec->cpu_user_features |= 1U << bit;
 184		else if (word == 1)
 185			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 186		else
 187			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
 188	}
 189
 190	return 1;
 191}
 192
 193static int __init feat_enable(struct dt_cpu_feature *f)
 194{
 195	if (f->hv_support != HV_SUPPORT_NONE) {
 196		if (f->hfscr_bit_nr != -1) {
 197			u64 hfscr = mfspr(SPRN_HFSCR);
 198			hfscr |= 1UL << f->hfscr_bit_nr;
 199			mtspr(SPRN_HFSCR, hfscr);
 200		}
 201	}
 202
 203	if (f->os_support != OS_SUPPORT_NONE) {
 204		if (f->fscr_bit_nr != -1) {
 205			u64 fscr = mfspr(SPRN_FSCR);
 206			fscr |= 1UL << f->fscr_bit_nr;
 207			mtspr(SPRN_FSCR, fscr);
 208		}
 209	}
 210
 211	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
 212		uint32_t word = f->hwcap_bit_nr / 32;
 213		uint32_t bit = f->hwcap_bit_nr % 32;
 214
 215		if (word == 0)
 216			cur_cpu_spec->cpu_user_features |= 1U << bit;
 217		else if (word == 1)
 218			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
 219		else
 220			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
 221	}
 222
 223	return 1;
 224}
 225
 226static int __init feat_disable(struct dt_cpu_feature *f)
 227{
 228	return 0;
 229}
 230
 231static int __init feat_enable_hv(struct dt_cpu_feature *f)
 232{
 233	u64 lpcr;
 234
 235	if (!hv_mode) {
 236		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
 237		return 0;
 238	}
 239
 240	mtspr(SPRN_LPID, 0);
 241
 242	lpcr = mfspr(SPRN_LPCR);
 243	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
 244	mtspr(SPRN_LPCR, lpcr);
 245
 246	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 247
 248	return 1;
 249}
 250
 251static int __init feat_enable_le(struct dt_cpu_feature *f)
 252{
 253	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
 254	return 1;
 255}
 256
 257static int __init feat_enable_smt(struct dt_cpu_feature *f)
 258{
 259	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
 260	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
 261	return 1;
 262}
 263
 264static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
 265{
 266	u64 lpcr;
 267
 268	/* Set PECE wakeup modes for ISA 207 */
 269	lpcr = mfspr(SPRN_LPCR);
 270	lpcr |=  LPCR_PECE0;
 271	lpcr |=  LPCR_PECE1;
 272	lpcr |=  LPCR_PECE2;
 273	mtspr(SPRN_LPCR, lpcr);
 274
 275	return 1;
 276}
 277
 278static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
 279{
 280	cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
 281
 282	return 1;
 283}
 284
 285static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
 286{
 287	u64 lpcr;
 288
 289	/* Set PECE wakeup modes for ISAv3.0B */
 290	lpcr = mfspr(SPRN_LPCR);
 291	lpcr |=  LPCR_PECE0;
 292	lpcr |=  LPCR_PECE1;
 293	lpcr |=  LPCR_PECE2;
 294	mtspr(SPRN_LPCR, lpcr);
 295
 296	return 1;
 297}
 298
 299static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
 300{
 301	u64 lpcr;
 302
 303	lpcr = mfspr(SPRN_LPCR);
 304	lpcr &= ~LPCR_ISL;
 305
 306	/* VRMASD */
 307	lpcr |= LPCR_VPM0;
 308	lpcr &= ~LPCR_VPM1;
 309	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
 310	mtspr(SPRN_LPCR, lpcr);
 311
 312	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 313	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 314
 315	return 1;
 316}
 317
 318static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
 319{
 320	u64 lpcr;
 321
 322	system_registers.lpcr_clear |= (LPCR_ISL | LPCR_UPRT | LPCR_HR);
 323	lpcr = mfspr(SPRN_LPCR);
 324	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
 325	mtspr(SPRN_LPCR, lpcr);
 326
 327	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 328	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 329
 330	return 1;
 331}
 332
 333
 334static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
 335{
 336#ifdef CONFIG_PPC_RADIX_MMU
 337	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
 338	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
 339	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
 340
 341	return 1;
 342#endif
 343	return 0;
 344}
 345
 346static int __init feat_enable_dscr(struct dt_cpu_feature *f)
 347{
 348	u64 lpcr;
 349
 350	feat_enable(f);
 351
 352	lpcr = mfspr(SPRN_LPCR);
 353	lpcr &= ~LPCR_DPFD;
 354	lpcr |=  (4UL << LPCR_DPFD_SH);
 355	mtspr(SPRN_LPCR, lpcr);
 356
 357	return 1;
 358}
 359
 360static void hfscr_pmu_enable(void)
 361{
 362	u64 hfscr = mfspr(SPRN_HFSCR);
 363	hfscr |= PPC_BIT(60);
 364	mtspr(SPRN_HFSCR, hfscr);
 365}
 366
 367static void init_pmu_power8(void)
 368{
 369	if (hv_mode) {
 370		mtspr(SPRN_MMCRC, 0);
 371		mtspr(SPRN_MMCRH, 0);
 372	}
 373
 374	mtspr(SPRN_MMCRA, 0);
 375	mtspr(SPRN_MMCR0, 0);
 376	mtspr(SPRN_MMCR1, 0);
 377	mtspr(SPRN_MMCR2, 0);
 378	mtspr(SPRN_MMCRS, 0);
 379}
 380
 381static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
 382{
 383	cur_cpu_spec->platform = "power8";
 384	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
 385
 386	return 1;
 387}
 388
 389static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
 390{
 391	hfscr_pmu_enable();
 392
 393	init_pmu_power8();
 394	init_pmu_registers = init_pmu_power8;
 395
 396	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 397	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 398	if (pvr_version_is(PVR_POWER8E))
 399		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
 400
 401	cur_cpu_spec->num_pmcs		= 6;
 402	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
 403	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
 404
 405	return 1;
 406}
 407
 408static void init_pmu_power9(void)
 409{
 410	if (hv_mode)
 411		mtspr(SPRN_MMCRC, 0);
 412
 413	mtspr(SPRN_MMCRA, 0);
 414	mtspr(SPRN_MMCR0, 0);
 415	mtspr(SPRN_MMCR1, 0);
 416	mtspr(SPRN_MMCR2, 0);
 417}
 418
 419static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
 420{
 421	cur_cpu_spec->platform = "power9";
 422	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
 423
 424	return 1;
 425}
 426
 427static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
 428{
 429	hfscr_pmu_enable();
 430
 431	init_pmu_power9();
 432	init_pmu_registers = init_pmu_power9;
 433
 434	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
 435	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
 436
 437	cur_cpu_spec->num_pmcs		= 6;
 438	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
 439	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
 440
 441	return 1;
 442}
 443
 444static int __init feat_enable_tm(struct dt_cpu_feature *f)
 445{
 446#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
 447	feat_enable(f);
 448	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
 449	return 1;
 450#endif
 451	return 0;
 452}
 453
 454static int __init feat_enable_fp(struct dt_cpu_feature *f)
 455{
 456	feat_enable(f);
 457	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
 458
 459	return 1;
 460}
 461
 462static int __init feat_enable_vector(struct dt_cpu_feature *f)
 463{
 464#ifdef CONFIG_ALTIVEC
 465	feat_enable(f);
 466	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
 467	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
 468	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
 469
 470	return 1;
 471#endif
 472	return 0;
 473}
 474
 475static int __init feat_enable_vsx(struct dt_cpu_feature *f)
 476{
 477#ifdef CONFIG_VSX
 478	feat_enable(f);
 479	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
 480	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
 481
 482	return 1;
 483#endif
 484	return 0;
 485}
 486
 487static int __init feat_enable_purr(struct dt_cpu_feature *f)
 488{
 489	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
 490
 491	return 1;
 492}
 493
 494static int __init feat_enable_ebb(struct dt_cpu_feature *f)
 495{
 496	/*
 497	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
 498	 * historically been related to the PMU facility. This may have
 499	 * to be decoupled if EBB becomes more generic. For now, follow
 500	 * existing convention.
 501	 */
 502	f->hwcap_bit_nr = -1;
 503	feat_enable(f);
 504
 505	return 1;
 506}
 507
 508static int __init feat_enable_dbell(struct dt_cpu_feature *f)
 509{
 510	u64 lpcr;
 511
 512	/* P9 has an HFSCR for privileged state */
 513	feat_enable(f);
 514
 515	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
 516
 517	lpcr = mfspr(SPRN_LPCR);
 518	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
 519	mtspr(SPRN_LPCR, lpcr);
 520
 521	return 1;
 522}
 523
 524static int __init feat_enable_hvi(struct dt_cpu_feature *f)
 525{
 526	u64 lpcr;
 527
 528	/*
 529	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
 530	 * are always delivered as hypervisor virtualization interrupts (HVI)
 531	 * rather than EE.
 532	 *
 533	 * However LPES0 is not set here, in the chance that an EE does get
 534	 * delivered to the host somehow, the EE handler would not expect it
 535	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
 536	 * happen if there is a bug in interrupt controller code, or IC is
 537	 * misconfigured in systemsim.
 538	 */
 539
 540	lpcr = mfspr(SPRN_LPCR);
 541	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
 542	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
 543	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
 544	mtspr(SPRN_LPCR, lpcr);
 545
 546	return 1;
 547}
 548
 549static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
 550{
 551	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
 552
 553	return 1;
 554}
 555
 556struct dt_cpu_feature_match {
 557	const char *name;
 558	int (*enable)(struct dt_cpu_feature *f);
 559	u64 cpu_ftr_bit_mask;
 560};
 561
 562static struct dt_cpu_feature_match __initdata
 563		dt_cpu_feature_match_table[] = {
 564	{"hypervisor", feat_enable_hv, 0},
 565	{"big-endian", feat_enable, 0},
 566	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
 567	{"smt", feat_enable_smt, 0},
 568	{"interrupt-facilities", feat_enable, 0},
 569	{"timer-facilities", feat_enable, 0},
 570	{"timer-facilities-v3", feat_enable, 0},
 571	{"debug-facilities", feat_enable, 0},
 572	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
 573	{"branch-tracing", feat_enable, 0},
 574	{"floating-point", feat_enable_fp, 0},
 575	{"vector", feat_enable_vector, 0},
 576	{"vector-scalar", feat_enable_vsx, 0},
 577	{"vector-scalar-v3", feat_enable, 0},
 578	{"decimal-floating-point", feat_enable, 0},
 579	{"decimal-integer", feat_enable, 0},
 580	{"quadword-load-store", feat_enable, 0},
 581	{"vector-crypto", feat_enable, 0},
 582	{"mmu-hash", feat_enable_mmu_hash, 0},
 583	{"mmu-radix", feat_enable_mmu_radix, 0},
 584	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
 585	{"virtual-page-class-key-protection", feat_enable, 0},
 586	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
 587	{"transactional-memory-v3", feat_enable_tm, 0},
 588	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
 589	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
 590	{"idle-nap", feat_enable_idle_nap, 0},
 591	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
 592	{"idle-stop", feat_enable_idle_stop, 0},
 593	{"machine-check-power8", feat_enable_mce_power8, 0},
 594	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
 595	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
 596	{"event-based-branch", feat_enable_ebb, 0},
 597	{"target-address-register", feat_enable, 0},
 598	{"branch-history-rolling-buffer", feat_enable, 0},
 599	{"control-register", feat_enable, CPU_FTR_CTRL},
 600	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
 601	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
 602	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
 603	{"no-execute", feat_enable, 0},
 604	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
 605	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
 606	{"coprocessor-icswx", feat_enable, 0},
 607	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
 608	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
 609	{"wait", feat_enable, 0},
 610	{"atomic-memory-operations", feat_enable, 0},
 611	{"branch-v3", feat_enable, 0},
 612	{"copy-paste", feat_enable, 0},
 613	{"decimal-floating-point-v3", feat_enable, 0},
 614	{"decimal-integer-v3", feat_enable, 0},
 615	{"fixed-point-v3", feat_enable, 0},
 616	{"floating-point-v3", feat_enable, 0},
 617	{"group-start-register", feat_enable, 0},
 618	{"pc-relative-addressing", feat_enable, 0},
 619	{"machine-check-power9", feat_enable_mce_power9, 0},
 620	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
 621	{"event-based-branch-v3", feat_enable, 0},
 622	{"random-number-generator", feat_enable, 0},
 623	{"system-call-vectored", feat_disable, 0},
 624	{"trace-interrupt-v3", feat_enable, 0},
 625	{"vector-v3", feat_enable, 0},
 626	{"vector-binary128", feat_enable, 0},
 627	{"vector-binary16", feat_enable, 0},
 628	{"wait-v3", feat_enable, 0},
 629};
 630
 631static bool __initdata using_dt_cpu_ftrs;
 632static bool __initdata enable_unknown = true;
 633
 634static int __init dt_cpu_ftrs_parse(char *str)
 635{
 636	if (!str)
 637		return 0;
 638
 639	if (!strcmp(str, "off"))
 640		using_dt_cpu_ftrs = false;
 641	else if (!strcmp(str, "known"))
 642		enable_unknown = false;
 643	else
 644		return 1;
 645
 646	return 0;
 647}
 648early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
 649
 650static void __init cpufeatures_setup_start(u32 isa)
 651{
 652	pr_info("setup for ISA %d\n", isa);
 653
 654	if (isa >= 3000) {
 655		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
 656		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
 657	}
 658}
 659
 660static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
 661{
 662	const struct dt_cpu_feature_match *m;
 663	bool known = false;
 664	int i;
 665
 666	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
 667		m = &dt_cpu_feature_match_table[i];
 668		if (!strcmp(f->name, m->name)) {
 669			known = true;
 670			if (m->enable(f)) {
 671				cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
 672				break;
 673			}
 674
 675			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
 676				f->name);
 677			return false;
 678		}
 679	}
 680
 681	if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
 682		pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
 683			f->name);
 684		return false;
 
 
 685	}
 686
 
 
 
 687	if (known)
 688		pr_debug("enabling: %s\n", f->name);
 689	else
 690		pr_debug("enabling: %s (unknown)\n", f->name);
 691
 692	return true;
 693}
 694
 695/*
 696 * Handle POWER9 broadcast tlbie invalidation issue using
 697 * cpu feature flag.
 698 */
 699static __init void update_tlbie_feature_flag(unsigned long pvr)
 700{
 701	if (PVR_VER(pvr) == PVR_POWER9) {
 702		/*
 703		 * Set the tlbie feature flag for anything below
 704		 * Nimbus DD 2.3 and Cumulus DD 1.3
 705		 */
 706		if ((pvr & 0xe000) == 0) {
 707			/* Nimbus */
 708			if ((pvr & 0xfff) < 0x203)
 709				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 710		} else if ((pvr & 0xc000) == 0) {
 711			/* Cumulus */
 712			if ((pvr & 0xfff) < 0x103)
 713				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 714		} else {
 715			WARN_ONCE(1, "Unknown PVR");
 716			cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
 717		}
 718
 719		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
 720	}
 721}
 722
 723static __init void cpufeatures_cpu_quirks(void)
 724{
 725	unsigned long version = mfspr(SPRN_PVR);
 726
 727	/*
 728	 * Not all quirks can be derived from the cpufeatures device tree.
 729	 */
 730	if ((version & 0xffffefff) == 0x004e0200)
 
 
 731		; /* DD2.0 has no feature flag */
 732	else if ((version & 0xffffefff) == 0x004e0201)
 733		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 734	else if ((version & 0xffffefff) == 0x004e0202) {
 735		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
 736		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
 737		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 738	} else if ((version & 0xffff0000) == 0x004e0000)
 739		/* DD2.1 and up have DD2_1 */
 740		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
 741
 742	if ((version & 0xffff0000) == 0x004e0000) {
 743		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
 744		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
 745	}
 746
 747	update_tlbie_feature_flag(version);
 748	/*
 749	 * PKEY was not in the initial base or feature node
 750	 * specification, but it should become optional in the next
 751	 * cpu feature version sequence.
 752	 */
 753	cur_cpu_spec->cpu_features |= CPU_FTR_PKEY;
 754}
 755
 756static void __init cpufeatures_setup_finished(void)
 757{
 758	cpufeatures_cpu_quirks();
 759
 760	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
 761		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
 762		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
 763	}
 764
 765	/* Make sure powerpc_base_platform is non-NULL */
 766	powerpc_base_platform = cur_cpu_spec->platform;
 767
 768	system_registers.lpcr = mfspr(SPRN_LPCR);
 769	system_registers.hfscr = mfspr(SPRN_HFSCR);
 770	system_registers.fscr = mfspr(SPRN_FSCR);
 771
 772	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
 773		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
 774}
 775
 776static int __init disabled_on_cmdline(void)
 777{
 778	unsigned long root, chosen;
 779	const char *p;
 780
 781	root = of_get_flat_dt_root();
 782	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
 783	if (chosen == -FDT_ERR_NOTFOUND)
 784		return false;
 785
 786	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
 787	if (!p)
 788		return false;
 789
 790	if (strstr(p, "dt_cpu_ftrs=off"))
 791		return true;
 792
 793	return false;
 794}
 795
 796static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
 797					int depth, void *data)
 798{
 799	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
 800	    && of_get_flat_dt_prop(node, "isa", NULL))
 801		return 1;
 802
 803	return 0;
 804}
 805
 806bool __init dt_cpu_ftrs_in_use(void)
 807{
 808	return using_dt_cpu_ftrs;
 809}
 810
 811bool __init dt_cpu_ftrs_init(void *fdt)
 812{
 813	using_dt_cpu_ftrs = false;
 814
 815	/* Setup and verify the FDT, if it fails we just bail */
 816	if (!early_init_dt_verify(fdt))
 817		return false;
 818
 819	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
 820		return false;
 821
 822	if (disabled_on_cmdline())
 823		return false;
 824
 825	cpufeatures_setup_cpu();
 826
 827	using_dt_cpu_ftrs = true;
 828	return true;
 829}
 830
 831static int nr_dt_cpu_features;
 832static struct dt_cpu_feature *dt_cpu_features;
 833
 834static int __init process_cpufeatures_node(unsigned long node,
 835					  const char *uname, int i)
 836{
 837	const __be32 *prop;
 838	struct dt_cpu_feature *f;
 839	int len;
 840
 841	f = &dt_cpu_features[i];
 
 842
 843	f->node = node;
 844
 845	f->name = uname;
 846
 847	prop = of_get_flat_dt_prop(node, "isa", &len);
 848	if (!prop) {
 849		pr_warn("%s: missing isa property\n", uname);
 850		return 0;
 851	}
 852	f->isa = be32_to_cpup(prop);
 853
 854	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
 855	if (!prop) {
 856		pr_warn("%s: missing usable-privilege property", uname);
 857		return 0;
 858	}
 859	f->usable_privilege = be32_to_cpup(prop);
 860
 861	prop = of_get_flat_dt_prop(node, "hv-support", &len);
 862	if (prop)
 863		f->hv_support = be32_to_cpup(prop);
 864	else
 865		f->hv_support = HV_SUPPORT_NONE;
 866
 867	prop = of_get_flat_dt_prop(node, "os-support", &len);
 868	if (prop)
 869		f->os_support = be32_to_cpup(prop);
 870	else
 871		f->os_support = OS_SUPPORT_NONE;
 872
 873	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
 874	if (prop)
 875		f->hfscr_bit_nr = be32_to_cpup(prop);
 876	else
 877		f->hfscr_bit_nr = -1;
 878	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
 879	if (prop)
 880		f->fscr_bit_nr = be32_to_cpup(prop);
 881	else
 882		f->fscr_bit_nr = -1;
 883	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
 884	if (prop)
 885		f->hwcap_bit_nr = be32_to_cpup(prop);
 886	else
 887		f->hwcap_bit_nr = -1;
 888
 889	if (f->usable_privilege & USABLE_HV) {
 890		if (!(mfmsr() & MSR_HV)) {
 891			pr_warn("%s: HV feature passed to guest\n", uname);
 892			return 0;
 893		}
 894
 895		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
 896			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
 897			return 0;
 898		}
 899
 900		if (f->hv_support == HV_SUPPORT_HFSCR) {
 901			if (f->hfscr_bit_nr == -1) {
 902				pr_warn("%s: missing hfscr_bit_nr\n", uname);
 903				return 0;
 904			}
 905		}
 906	} else {
 907		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
 908			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
 909			return 0;
 910		}
 911	}
 912
 913	if (f->usable_privilege & USABLE_OS) {
 914		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
 915			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
 916			return 0;
 917		}
 918
 919		if (f->os_support == OS_SUPPORT_FSCR) {
 920			if (f->fscr_bit_nr == -1) {
 921				pr_warn("%s: missing fscr_bit_nr\n", uname);
 922				return 0;
 923			}
 924		}
 925	} else {
 926		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
 927			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
 928			return 0;
 929		}
 930	}
 931
 932	if (!(f->usable_privilege & USABLE_PR)) {
 933		if (f->hwcap_bit_nr != -1) {
 934			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
 935			return 0;
 936		}
 937	}
 938
 939	/* Do all the independent features in the first pass */
 940	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
 941		if (cpufeatures_process_feature(f))
 942			f->enabled = 1;
 943		else
 944			f->disabled = 1;
 945	}
 946
 947	return 0;
 948}
 949
 950static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
 951{
 952	const __be32 *prop;
 953	int len;
 954	int nr_deps;
 955	int i;
 956
 957	if (f->enabled || f->disabled)
 958		return;
 959
 960	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
 961	if (!prop) {
 962		pr_warn("%s: missing dependencies property", f->name);
 963		return;
 964	}
 965
 966	nr_deps = len / sizeof(int);
 967
 968	for (i = 0; i < nr_deps; i++) {
 969		unsigned long phandle = be32_to_cpu(prop[i]);
 970		int j;
 971
 972		for (j = 0; j < nr_dt_cpu_features; j++) {
 973			struct dt_cpu_feature *d = &dt_cpu_features[j];
 974
 975			if (of_get_flat_dt_phandle(d->node) == phandle) {
 976				cpufeatures_deps_enable(d);
 977				if (d->disabled) {
 978					f->disabled = 1;
 979					return;
 980				}
 981			}
 982		}
 983	}
 984
 985	if (cpufeatures_process_feature(f))
 986		f->enabled = 1;
 987	else
 988		f->disabled = 1;
 989}
 990
 991static int __init scan_cpufeatures_subnodes(unsigned long node,
 992					  const char *uname,
 993					  void *data)
 994{
 995	int *count = data;
 996
 997	process_cpufeatures_node(node, uname, *count);
 998
 999	(*count)++;
1000
1001	return 0;
1002}
1003
1004static int __init count_cpufeatures_subnodes(unsigned long node,
1005					  const char *uname,
1006					  void *data)
1007{
1008	int *count = data;
1009
1010	(*count)++;
1011
1012	return 0;
1013}
1014
1015static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1016					    *uname, int depth, void *data)
1017{
1018	const __be32 *prop;
1019	int count, i;
1020	u32 isa;
1021
1022	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1023	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1024		return 0;
1025
1026	prop = of_get_flat_dt_prop(node, "isa", NULL);
1027	if (!prop)
1028		/* We checked before, "can't happen" */
1029		return 0;
1030
1031	isa = be32_to_cpup(prop);
1032
1033	/* Count and allocate space for cpu features */
1034	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1035						&nr_dt_cpu_features);
1036	dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1037	if (!dt_cpu_features)
1038		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1039		      __func__,
1040		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1041		      PAGE_SIZE);
1042
1043	cpufeatures_setup_start(isa);
1044
1045	/* Scan nodes into dt_cpu_features and enable those without deps  */
1046	count = 0;
1047	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1048
1049	/* Recursive enable remaining features with dependencies */
1050	for (i = 0; i < nr_dt_cpu_features; i++) {
1051		struct dt_cpu_feature *f = &dt_cpu_features[i];
1052
1053		cpufeatures_deps_enable(f);
1054	}
1055
1056	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1057	if (prop && strlen((char *)prop) != 0) {
1058		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1059		cur_cpu_spec->cpu_name = dt_cpu_name;
1060	}
1061
1062	cpufeatures_setup_finished();
1063
1064	memblock_free(__pa(dt_cpu_features),
1065			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1066
1067	return 0;
1068}
1069
1070void __init dt_cpu_ftrs_scan(void)
1071{
1072	if (!using_dt_cpu_ftrs)
1073		return;
1074
1075	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1076}