1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2017, Nicholas Piggin, IBM Corporation
4  */
5 
6 #define pr_fmt(fmt) "dt-cpu-ftrs: " fmt
7 
8 #include <linux/export.h>
9 #include <linux/init.h>
10 #include <linux/jump_label.h>
11 #include <linux/libfdt.h>
12 #include <linux/memblock.h>
13 #include <linux/printk.h>
14 #include <linux/sched.h>
15 #include <linux/string.h>
16 #include <linux/threads.h>
17 
18 #include <asm/cputable.h>
19 #include <asm/dt_cpu_ftrs.h>
20 #include <asm/mce.h>
21 #include <asm/mmu.h>
22 #include <asm/oprofile_impl.h>
23 #include <asm/prom.h>
24 #include <asm/setup.h>
25 
26 
27 /* Device-tree visible constants follow */
28 #define ISA_V3_0B       3000
29 #define ISA_V3_1        3100
30 
31 #define USABLE_PR               (1U << 0)
32 #define USABLE_OS               (1U << 1)
33 #define USABLE_HV               (1U << 2)
34 
35 #define HV_SUPPORT_HFSCR        (1U << 0)
36 #define OS_SUPPORT_FSCR         (1U << 0)
37 
38 /* For parsing, we define all bits set as "NONE" case */
39 #define HV_SUPPORT_NONE		0xffffffffU
40 #define OS_SUPPORT_NONE		0xffffffffU
41 
42 struct dt_cpu_feature {
43 	const char *name;
44 	uint32_t isa;
45 	uint32_t usable_privilege;
46 	uint32_t hv_support;
47 	uint32_t os_support;
48 	uint32_t hfscr_bit_nr;
49 	uint32_t fscr_bit_nr;
50 	uint32_t hwcap_bit_nr;
51 	/* fdt parsing */
52 	unsigned long node;
53 	int enabled;
54 	int disabled;
55 };
56 
57 #define MMU_FTRS_HASH_BASE (MMU_FTRS_POWER8)
58 
59 #define COMMON_USER_BASE	(PPC_FEATURE_32 | PPC_FEATURE_64 | \
60 				 PPC_FEATURE_ARCH_2_06 |\
61 				 PPC_FEATURE_ICACHE_SNOOP)
62 #define COMMON_USER2_BASE	(PPC_FEATURE2_ARCH_2_07 | \
63 				 PPC_FEATURE2_ISEL)
64 /*
65  * Set up the base CPU
66  */
67 
68 static int hv_mode;
69 
70 static struct {
71 	u64	lpcr;
72 	u64	hfscr;
73 	u64	fscr;
74 	u64	pcr;
75 } system_registers;
76 
77 static void (*init_pmu_registers)(void);
78 
79 static void __restore_cpu_cpufeatures(void)
80 {
81 	mtspr(SPRN_LPCR, system_registers.lpcr);
82 	if (hv_mode) {
83 		mtspr(SPRN_LPID, 0);
84 		mtspr(SPRN_HFSCR, system_registers.hfscr);
85 		mtspr(SPRN_PCR, system_registers.pcr);
86 	}
87 	mtspr(SPRN_FSCR, system_registers.fscr);
88 
89 	if (init_pmu_registers)
90 		init_pmu_registers();
91 }
92 
93 static char dt_cpu_name[64];
94 
95 static struct cpu_spec __initdata base_cpu_spec = {
96 	.cpu_name		= NULL,
97 	.cpu_features		= CPU_FTRS_DT_CPU_BASE,
98 	.cpu_user_features	= COMMON_USER_BASE,
99 	.cpu_user_features2	= COMMON_USER2_BASE,
100 	.mmu_features		= 0,
101 	.icache_bsize		= 32, /* minimum block size, fixed by */
102 	.dcache_bsize		= 32, /* cache info init.             */
103 	.num_pmcs		= 0,
104 	.pmc_type		= PPC_PMC_DEFAULT,
105 	.oprofile_cpu_type	= NULL,
106 	.oprofile_type		= PPC_OPROFILE_INVALID,
107 	.cpu_setup		= NULL,
108 	.cpu_restore		= __restore_cpu_cpufeatures,
109 	.machine_check_early	= NULL,
110 	.platform		= NULL,
111 };
112 
113 static void __init cpufeatures_setup_cpu(void)
114 {
115 	set_cur_cpu_spec(&base_cpu_spec);
116 
117 	cur_cpu_spec->pvr_mask = -1;
118 	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
119 
120 	/* Initialize the base environment -- clear FSCR/HFSCR.  */
121 	hv_mode = !!(mfmsr() & MSR_HV);
122 	if (hv_mode) {
123 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
124 		mtspr(SPRN_HFSCR, 0);
125 	}
126 	mtspr(SPRN_FSCR, 0);
127 	mtspr(SPRN_PCR, PCR_MASK);
128 
129 	/*
130 	 * LPCR does not get cleared, to match behaviour with secondaries
131 	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
132 	 * could clear LPCR too.
133 	 */
134 }
135 
136 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
137 {
138 	if (f->hv_support == HV_SUPPORT_NONE) {
139 	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
140 		u64 hfscr = mfspr(SPRN_HFSCR);
141 		hfscr |= 1UL << f->hfscr_bit_nr;
142 		mtspr(SPRN_HFSCR, hfscr);
143 	} else {
144 		/* Does not have a known recipe */
145 		return 0;
146 	}
147 
148 	if (f->os_support == OS_SUPPORT_NONE) {
149 	} else if (f->os_support & OS_SUPPORT_FSCR) {
150 		u64 fscr = mfspr(SPRN_FSCR);
151 		fscr |= 1UL << f->fscr_bit_nr;
152 		mtspr(SPRN_FSCR, fscr);
153 	} else {
154 		/* Does not have a known recipe */
155 		return 0;
156 	}
157 
158 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
159 		uint32_t word = f->hwcap_bit_nr / 32;
160 		uint32_t bit = f->hwcap_bit_nr % 32;
161 
162 		if (word == 0)
163 			cur_cpu_spec->cpu_user_features |= 1U << bit;
164 		else if (word == 1)
165 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
166 		else
167 			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
168 	}
169 
170 	return 1;
171 }
172 
173 static int __init feat_enable(struct dt_cpu_feature *f)
174 {
175 	if (f->hv_support != HV_SUPPORT_NONE) {
176 		if (f->hfscr_bit_nr != -1) {
177 			u64 hfscr = mfspr(SPRN_HFSCR);
178 			hfscr |= 1UL << f->hfscr_bit_nr;
179 			mtspr(SPRN_HFSCR, hfscr);
180 		}
181 	}
182 
183 	if (f->os_support != OS_SUPPORT_NONE) {
184 		if (f->fscr_bit_nr != -1) {
185 			u64 fscr = mfspr(SPRN_FSCR);
186 			fscr |= 1UL << f->fscr_bit_nr;
187 			mtspr(SPRN_FSCR, fscr);
188 		}
189 	}
190 
191 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
192 		uint32_t word = f->hwcap_bit_nr / 32;
193 		uint32_t bit = f->hwcap_bit_nr % 32;
194 
195 		if (word == 0)
196 			cur_cpu_spec->cpu_user_features |= 1U << bit;
197 		else if (word == 1)
198 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
199 		else
200 			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
201 	}
202 
203 	return 1;
204 }
205 
206 static int __init feat_disable(struct dt_cpu_feature *f)
207 {
208 	return 0;
209 }
210 
211 static int __init feat_enable_hv(struct dt_cpu_feature *f)
212 {
213 	u64 lpcr;
214 
215 	if (!hv_mode) {
216 		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
217 		return 0;
218 	}
219 
220 	mtspr(SPRN_LPID, 0);
221 
222 	lpcr = mfspr(SPRN_LPCR);
223 	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
224 	mtspr(SPRN_LPCR, lpcr);
225 
226 	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
227 
228 	return 1;
229 }
230 
231 static int __init feat_enable_le(struct dt_cpu_feature *f)
232 {
233 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
234 	return 1;
235 }
236 
237 static int __init feat_enable_smt(struct dt_cpu_feature *f)
238 {
239 	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
240 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
241 	return 1;
242 }
243 
244 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
245 {
246 	u64 lpcr;
247 
248 	/* Set PECE wakeup modes for ISA 207 */
249 	lpcr = mfspr(SPRN_LPCR);
250 	lpcr |=  LPCR_PECE0;
251 	lpcr |=  LPCR_PECE1;
252 	lpcr |=  LPCR_PECE2;
253 	mtspr(SPRN_LPCR, lpcr);
254 
255 	return 1;
256 }
257 
258 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
259 {
260 	u64 lpcr;
261 
262 	/* Set PECE wakeup modes for ISAv3.0B */
263 	lpcr = mfspr(SPRN_LPCR);
264 	lpcr |=  LPCR_PECE0;
265 	lpcr |=  LPCR_PECE1;
266 	lpcr |=  LPCR_PECE2;
267 	mtspr(SPRN_LPCR, lpcr);
268 
269 	return 1;
270 }
271 
272 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
273 {
274 	u64 lpcr;
275 
276 	lpcr = mfspr(SPRN_LPCR);
277 	lpcr &= ~LPCR_ISL;
278 
279 	/* VRMASD */
280 	lpcr |= LPCR_VPM0;
281 	lpcr &= ~LPCR_VPM1;
282 	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
283 	mtspr(SPRN_LPCR, lpcr);
284 
285 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
286 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
287 
288 	return 1;
289 }
290 
291 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
292 {
293 	u64 lpcr;
294 
295 	lpcr = mfspr(SPRN_LPCR);
296 	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
297 	mtspr(SPRN_LPCR, lpcr);
298 
299 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
300 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
301 
302 	return 1;
303 }
304 
305 
306 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
307 {
308 #ifdef CONFIG_PPC_RADIX_MMU
309 	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
310 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
311 	cur_cpu_spec->mmu_features |= MMU_FTR_GTSE;
312 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
313 
314 	return 1;
315 #endif
316 	return 0;
317 }
318 
319 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
320 {
321 	u64 lpcr;
322 
323 	/*
324 	 * Linux relies on FSCR[DSCR] being clear, so that we can take the
325 	 * facility unavailable interrupt and track the task's usage of DSCR.
326 	 * See facility_unavailable_exception().
327 	 * Clear the bit here so that feat_enable() doesn't set it.
328 	 */
329 	f->fscr_bit_nr = -1;
330 
331 	feat_enable(f);
332 
333 	lpcr = mfspr(SPRN_LPCR);
334 	lpcr &= ~LPCR_DPFD;
335 	lpcr |=  (4UL << LPCR_DPFD_SH);
336 	mtspr(SPRN_LPCR, lpcr);
337 
338 	return 1;
339 }
340 
341 static void hfscr_pmu_enable(void)
342 {
343 	u64 hfscr = mfspr(SPRN_HFSCR);
344 	hfscr |= PPC_BIT(60);
345 	mtspr(SPRN_HFSCR, hfscr);
346 }
347 
348 static void init_pmu_power8(void)
349 {
350 	if (hv_mode) {
351 		mtspr(SPRN_MMCRC, 0);
352 		mtspr(SPRN_MMCRH, 0);
353 	}
354 
355 	mtspr(SPRN_MMCRA, 0);
356 	mtspr(SPRN_MMCR0, 0);
357 	mtspr(SPRN_MMCR1, 0);
358 	mtspr(SPRN_MMCR2, 0);
359 	mtspr(SPRN_MMCRS, 0);
360 }
361 
362 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
363 {
364 	cur_cpu_spec->platform = "power8";
365 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
366 
367 	return 1;
368 }
369 
370 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
371 {
372 	hfscr_pmu_enable();
373 
374 	init_pmu_power8();
375 	init_pmu_registers = init_pmu_power8;
376 
377 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
378 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
379 	if (pvr_version_is(PVR_POWER8E))
380 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
381 
382 	cur_cpu_spec->num_pmcs		= 6;
383 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
384 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
385 
386 	return 1;
387 }
388 
389 static void init_pmu_power9(void)
390 {
391 	if (hv_mode)
392 		mtspr(SPRN_MMCRC, 0);
393 
394 	mtspr(SPRN_MMCRA, 0);
395 	mtspr(SPRN_MMCR0, 0);
396 	mtspr(SPRN_MMCR1, 0);
397 	mtspr(SPRN_MMCR2, 0);
398 }
399 
400 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
401 {
402 	cur_cpu_spec->platform = "power9";
403 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
404 
405 	return 1;
406 }
407 
408 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
409 {
410 	hfscr_pmu_enable();
411 
412 	init_pmu_power9();
413 	init_pmu_registers = init_pmu_power9;
414 
415 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
416 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
417 
418 	cur_cpu_spec->num_pmcs		= 6;
419 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
420 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
421 
422 	return 1;
423 }
424 
425 static void init_pmu_power10(void)
426 {
427 	init_pmu_power9();
428 
429 	mtspr(SPRN_MMCR3, 0);
430 	mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
431 	mtspr(SPRN_MMCR0, MMCR0_PMCCEXT);
432 }
433 
434 static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
435 {
436 	hfscr_pmu_enable();
437 
438 	init_pmu_power10();
439 	init_pmu_registers = init_pmu_power10;
440 
441 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
442 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
443 
444 	cur_cpu_spec->num_pmcs          = 6;
445 	cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
446 	cur_cpu_spec->oprofile_cpu_type = "ppc64/power10";
447 
448 	return 1;
449 }
450 
451 static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
452 {
453 	cur_cpu_spec->platform = "power10";
454 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
455 
456 	return 1;
457 }
458 
459 static int __init feat_enable_tm(struct dt_cpu_feature *f)
460 {
461 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
462 	feat_enable(f);
463 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
464 	return 1;
465 #endif
466 	return 0;
467 }
468 
469 static int __init feat_enable_fp(struct dt_cpu_feature *f)
470 {
471 	feat_enable(f);
472 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
473 
474 	return 1;
475 }
476 
477 static int __init feat_enable_vector(struct dt_cpu_feature *f)
478 {
479 #ifdef CONFIG_ALTIVEC
480 	feat_enable(f);
481 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
482 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
483 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
484 
485 	return 1;
486 #endif
487 	return 0;
488 }
489 
490 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
491 {
492 #ifdef CONFIG_VSX
493 	feat_enable(f);
494 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
495 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
496 
497 	return 1;
498 #endif
499 	return 0;
500 }
501 
502 static int __init feat_enable_purr(struct dt_cpu_feature *f)
503 {
504 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
505 
506 	return 1;
507 }
508 
509 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
510 {
511 	/*
512 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
513 	 * historically been related to the PMU facility. This may have
514 	 * to be decoupled if EBB becomes more generic. For now, follow
515 	 * existing convention.
516 	 */
517 	f->hwcap_bit_nr = -1;
518 	feat_enable(f);
519 
520 	return 1;
521 }
522 
523 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
524 {
525 	u64 lpcr;
526 
527 	/* P9 has an HFSCR for privileged state */
528 	feat_enable(f);
529 
530 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
531 
532 	lpcr = mfspr(SPRN_LPCR);
533 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
534 	mtspr(SPRN_LPCR, lpcr);
535 
536 	return 1;
537 }
538 
539 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
540 {
541 	u64 lpcr;
542 
543 	/*
544 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
545 	 * are always delivered as hypervisor virtualization interrupts (HVI)
546 	 * rather than EE.
547 	 *
548 	 * However LPES0 is not set here, in the chance that an EE does get
549 	 * delivered to the host somehow, the EE handler would not expect it
550 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
551 	 * happen if there is a bug in interrupt controller code, or IC is
552 	 * misconfigured in systemsim.
553 	 */
554 
555 	lpcr = mfspr(SPRN_LPCR);
556 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
557 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
558 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
559 	mtspr(SPRN_LPCR, lpcr);
560 
561 	return 1;
562 }
563 
564 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
565 {
566 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
567 
568 	return 1;
569 }
570 
571 static int __init feat_enable_mma(struct dt_cpu_feature *f)
572 {
573 	u64 pcr;
574 
575 	feat_enable(f);
576 	pcr = mfspr(SPRN_PCR);
577 	pcr &= ~PCR_MMA_DIS;
578 	mtspr(SPRN_PCR, pcr);
579 
580 	return 1;
581 }
582 
583 struct dt_cpu_feature_match {
584 	const char *name;
585 	int (*enable)(struct dt_cpu_feature *f);
586 	u64 cpu_ftr_bit_mask;
587 };
588 
589 static struct dt_cpu_feature_match __initdata
590 		dt_cpu_feature_match_table[] = {
591 	{"hypervisor", feat_enable_hv, 0},
592 	{"big-endian", feat_enable, 0},
593 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
594 	{"smt", feat_enable_smt, 0},
595 	{"interrupt-facilities", feat_enable, 0},
596 	{"system-call-vectored", feat_enable, 0},
597 	{"timer-facilities", feat_enable, 0},
598 	{"timer-facilities-v3", feat_enable, 0},
599 	{"debug-facilities", feat_enable, 0},
600 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
601 	{"branch-tracing", feat_enable, 0},
602 	{"floating-point", feat_enable_fp, 0},
603 	{"vector", feat_enable_vector, 0},
604 	{"vector-scalar", feat_enable_vsx, 0},
605 	{"vector-scalar-v3", feat_enable, 0},
606 	{"decimal-floating-point", feat_enable, 0},
607 	{"decimal-integer", feat_enable, 0},
608 	{"quadword-load-store", feat_enable, 0},
609 	{"vector-crypto", feat_enable, 0},
610 	{"mmu-hash", feat_enable_mmu_hash, 0},
611 	{"mmu-radix", feat_enable_mmu_radix, 0},
612 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
613 	{"virtual-page-class-key-protection", feat_enable, 0},
614 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
615 	{"transactional-memory-v3", feat_enable_tm, 0},
616 	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
617 	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
618 	{"idle-nap", feat_enable_idle_nap, 0},
619 	/* alignment-interrupt-dsisr ignored */
620 	{"idle-stop", feat_enable_idle_stop, 0},
621 	{"machine-check-power8", feat_enable_mce_power8, 0},
622 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
623 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
624 	{"event-based-branch", feat_enable_ebb, 0},
625 	{"target-address-register", feat_enable, 0},
626 	{"branch-history-rolling-buffer", feat_enable, 0},
627 	{"control-register", feat_enable, CPU_FTR_CTRL},
628 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
629 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
630 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
631 	{"no-execute", feat_enable, 0},
632 	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
633 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
634 	{"coprocessor-icswx", feat_enable, 0},
635 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
636 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
637 	{"wait", feat_enable, 0},
638 	{"atomic-memory-operations", feat_enable, 0},
639 	{"branch-v3", feat_enable, 0},
640 	{"copy-paste", feat_enable, 0},
641 	{"decimal-floating-point-v3", feat_enable, 0},
642 	{"decimal-integer-v3", feat_enable, 0},
643 	{"fixed-point-v3", feat_enable, 0},
644 	{"floating-point-v3", feat_enable, 0},
645 	{"group-start-register", feat_enable, 0},
646 	{"pc-relative-addressing", feat_enable, 0},
647 	{"machine-check-power9", feat_enable_mce_power9, 0},
648 	{"machine-check-power10", feat_enable_mce_power10, 0},
649 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
650 	{"performance-monitor-power10", feat_enable_pmu_power10, 0},
651 	{"event-based-branch-v3", feat_enable, 0},
652 	{"random-number-generator", feat_enable, 0},
653 	{"system-call-vectored", feat_disable, 0},
654 	{"trace-interrupt-v3", feat_enable, 0},
655 	{"vector-v3", feat_enable, 0},
656 	{"vector-binary128", feat_enable, 0},
657 	{"vector-binary16", feat_enable, 0},
658 	{"wait-v3", feat_enable, 0},
659 	{"prefix-instructions", feat_enable, 0},
660 	{"matrix-multiply-assist", feat_enable_mma, 0},
661 	{"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
662 };
663 
664 static bool __initdata using_dt_cpu_ftrs;
665 static bool __initdata enable_unknown = true;
666 
667 static int __init dt_cpu_ftrs_parse(char *str)
668 {
669 	if (!str)
670 		return 0;
671 
672 	if (!strcmp(str, "off"))
673 		using_dt_cpu_ftrs = false;
674 	else if (!strcmp(str, "known"))
675 		enable_unknown = false;
676 	else
677 		return 1;
678 
679 	return 0;
680 }
681 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
682 
683 static void __init cpufeatures_setup_start(u32 isa)
684 {
685 	pr_info("setup for ISA %d\n", isa);
686 
687 	if (isa >= ISA_V3_0B) {
688 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
689 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
690 	}
691 
692 	if (isa >= ISA_V3_1) {
693 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
694 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
695 	}
696 }
697 
698 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
699 {
700 	const struct dt_cpu_feature_match *m;
701 	bool known = false;
702 	int i;
703 
704 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
705 		m = &dt_cpu_feature_match_table[i];
706 		if (!strcmp(f->name, m->name)) {
707 			known = true;
708 			if (m->enable(f)) {
709 				cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
710 				break;
711 			}
712 
713 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
714 				f->name);
715 			return false;
716 		}
717 	}
718 
719 	if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
720 		pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
721 			f->name);
722 		return false;
723 	}
724 
725 	if (known)
726 		pr_debug("enabling: %s\n", f->name);
727 	else
728 		pr_debug("enabling: %s (unknown)\n", f->name);
729 
730 	return true;
731 }
732 
733 /*
734  * Handle POWER9 broadcast tlbie invalidation issue using
735  * cpu feature flag.
736  */
737 static __init void update_tlbie_feature_flag(unsigned long pvr)
738 {
739 	if (PVR_VER(pvr) == PVR_POWER9) {
740 		/*
741 		 * Set the tlbie feature flag for anything below
742 		 * Nimbus DD 2.3 and Cumulus DD 1.3
743 		 */
744 		if ((pvr & 0xe000) == 0) {
745 			/* Nimbus */
746 			if ((pvr & 0xfff) < 0x203)
747 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
748 		} else if ((pvr & 0xc000) == 0) {
749 			/* Cumulus */
750 			if ((pvr & 0xfff) < 0x103)
751 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
752 		} else {
753 			WARN_ONCE(1, "Unknown PVR");
754 			cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
755 		}
756 
757 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
758 	}
759 }
760 
761 static __init void cpufeatures_cpu_quirks(void)
762 {
763 	unsigned long version = mfspr(SPRN_PVR);
764 
765 	/*
766 	 * Not all quirks can be derived from the cpufeatures device tree.
767 	 */
768 	if ((version & 0xffffefff) == 0x004e0200) {
769 		/* DD2.0 has no feature flag */
770 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
771 	} else if ((version & 0xffffefff) == 0x004e0201) {
772 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
773 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
774 	} else if ((version & 0xffffefff) == 0x004e0202) {
775 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
776 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
777 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
778 	} else if ((version & 0xffff0000) == 0x004e0000) {
779 		/* DD2.1 and up have DD2_1 */
780 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
781 	}
782 
783 	if ((version & 0xffff0000) == 0x004e0000) {
784 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
785 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
786 	}
787 
788 	update_tlbie_feature_flag(version);
789 }
790 
791 static void __init cpufeatures_setup_finished(void)
792 {
793 	cpufeatures_cpu_quirks();
794 
795 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
796 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
797 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
798 	}
799 
800 	/* Make sure powerpc_base_platform is non-NULL */
801 	powerpc_base_platform = cur_cpu_spec->platform;
802 
803 	system_registers.lpcr = mfspr(SPRN_LPCR);
804 	system_registers.hfscr = mfspr(SPRN_HFSCR);
805 	system_registers.fscr = mfspr(SPRN_FSCR);
806 	system_registers.pcr = mfspr(SPRN_PCR);
807 
808 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
809 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
810 }
811 
812 static int __init disabled_on_cmdline(void)
813 {
814 	unsigned long root, chosen;
815 	const char *p;
816 
817 	root = of_get_flat_dt_root();
818 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
819 	if (chosen == -FDT_ERR_NOTFOUND)
820 		return false;
821 
822 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
823 	if (!p)
824 		return false;
825 
826 	if (strstr(p, "dt_cpu_ftrs=off"))
827 		return true;
828 
829 	return false;
830 }
831 
832 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
833 					int depth, void *data)
834 {
835 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
836 	    && of_get_flat_dt_prop(node, "isa", NULL))
837 		return 1;
838 
839 	return 0;
840 }
841 
842 bool __init dt_cpu_ftrs_in_use(void)
843 {
844 	return using_dt_cpu_ftrs;
845 }
846 
847 bool __init dt_cpu_ftrs_init(void *fdt)
848 {
849 	using_dt_cpu_ftrs = false;
850 
851 	/* Setup and verify the FDT, if it fails we just bail */
852 	if (!early_init_dt_verify(fdt))
853 		return false;
854 
855 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
856 		return false;
857 
858 	if (disabled_on_cmdline())
859 		return false;
860 
861 	cpufeatures_setup_cpu();
862 
863 	using_dt_cpu_ftrs = true;
864 	return true;
865 }
866 
867 static int nr_dt_cpu_features;
868 static struct dt_cpu_feature *dt_cpu_features;
869 
870 static int __init process_cpufeatures_node(unsigned long node,
871 					  const char *uname, int i)
872 {
873 	const __be32 *prop;
874 	struct dt_cpu_feature *f;
875 	int len;
876 
877 	f = &dt_cpu_features[i];
878 
879 	f->node = node;
880 
881 	f->name = uname;
882 
883 	prop = of_get_flat_dt_prop(node, "isa", &len);
884 	if (!prop) {
885 		pr_warn("%s: missing isa property\n", uname);
886 		return 0;
887 	}
888 	f->isa = be32_to_cpup(prop);
889 
890 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
891 	if (!prop) {
892 		pr_warn("%s: missing usable-privilege property", uname);
893 		return 0;
894 	}
895 	f->usable_privilege = be32_to_cpup(prop);
896 
897 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
898 	if (prop)
899 		f->hv_support = be32_to_cpup(prop);
900 	else
901 		f->hv_support = HV_SUPPORT_NONE;
902 
903 	prop = of_get_flat_dt_prop(node, "os-support", &len);
904 	if (prop)
905 		f->os_support = be32_to_cpup(prop);
906 	else
907 		f->os_support = OS_SUPPORT_NONE;
908 
909 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
910 	if (prop)
911 		f->hfscr_bit_nr = be32_to_cpup(prop);
912 	else
913 		f->hfscr_bit_nr = -1;
914 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
915 	if (prop)
916 		f->fscr_bit_nr = be32_to_cpup(prop);
917 	else
918 		f->fscr_bit_nr = -1;
919 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
920 	if (prop)
921 		f->hwcap_bit_nr = be32_to_cpup(prop);
922 	else
923 		f->hwcap_bit_nr = -1;
924 
925 	if (f->usable_privilege & USABLE_HV) {
926 		if (!(mfmsr() & MSR_HV)) {
927 			pr_warn("%s: HV feature passed to guest\n", uname);
928 			return 0;
929 		}
930 
931 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
932 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
933 			return 0;
934 		}
935 
936 		if (f->hv_support == HV_SUPPORT_HFSCR) {
937 			if (f->hfscr_bit_nr == -1) {
938 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
939 				return 0;
940 			}
941 		}
942 	} else {
943 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
944 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
945 			return 0;
946 		}
947 	}
948 
949 	if (f->usable_privilege & USABLE_OS) {
950 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
951 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
952 			return 0;
953 		}
954 
955 		if (f->os_support == OS_SUPPORT_FSCR) {
956 			if (f->fscr_bit_nr == -1) {
957 				pr_warn("%s: missing fscr_bit_nr\n", uname);
958 				return 0;
959 			}
960 		}
961 	} else {
962 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
963 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
964 			return 0;
965 		}
966 	}
967 
968 	if (!(f->usable_privilege & USABLE_PR)) {
969 		if (f->hwcap_bit_nr != -1) {
970 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
971 			return 0;
972 		}
973 	}
974 
975 	/* Do all the independent features in the first pass */
976 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
977 		if (cpufeatures_process_feature(f))
978 			f->enabled = 1;
979 		else
980 			f->disabled = 1;
981 	}
982 
983 	return 0;
984 }
985 
986 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
987 {
988 	const __be32 *prop;
989 	int len;
990 	int nr_deps;
991 	int i;
992 
993 	if (f->enabled || f->disabled)
994 		return;
995 
996 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
997 	if (!prop) {
998 		pr_warn("%s: missing dependencies property", f->name);
999 		return;
1000 	}
1001 
1002 	nr_deps = len / sizeof(int);
1003 
1004 	for (i = 0; i < nr_deps; i++) {
1005 		unsigned long phandle = be32_to_cpu(prop[i]);
1006 		int j;
1007 
1008 		for (j = 0; j < nr_dt_cpu_features; j++) {
1009 			struct dt_cpu_feature *d = &dt_cpu_features[j];
1010 
1011 			if (of_get_flat_dt_phandle(d->node) == phandle) {
1012 				cpufeatures_deps_enable(d);
1013 				if (d->disabled) {
1014 					f->disabled = 1;
1015 					return;
1016 				}
1017 			}
1018 		}
1019 	}
1020 
1021 	if (cpufeatures_process_feature(f))
1022 		f->enabled = 1;
1023 	else
1024 		f->disabled = 1;
1025 }
1026 
1027 static int __init scan_cpufeatures_subnodes(unsigned long node,
1028 					  const char *uname,
1029 					  void *data)
1030 {
1031 	int *count = data;
1032 
1033 	process_cpufeatures_node(node, uname, *count);
1034 
1035 	(*count)++;
1036 
1037 	return 0;
1038 }
1039 
1040 static int __init count_cpufeatures_subnodes(unsigned long node,
1041 					  const char *uname,
1042 					  void *data)
1043 {
1044 	int *count = data;
1045 
1046 	(*count)++;
1047 
1048 	return 0;
1049 }
1050 
1051 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1052 					    *uname, int depth, void *data)
1053 {
1054 	const __be32 *prop;
1055 	int count, i;
1056 	u32 isa;
1057 
1058 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1059 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1060 		return 0;
1061 
1062 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1063 	if (!prop)
1064 		/* We checked before, "can't happen" */
1065 		return 0;
1066 
1067 	isa = be32_to_cpup(prop);
1068 
1069 	/* Count and allocate space for cpu features */
1070 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1071 						&nr_dt_cpu_features);
1072 	dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1073 	if (!dt_cpu_features)
1074 		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1075 		      __func__,
1076 		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1077 		      PAGE_SIZE);
1078 
1079 	cpufeatures_setup_start(isa);
1080 
1081 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1082 	count = 0;
1083 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1084 
1085 	/* Recursive enable remaining features with dependencies */
1086 	for (i = 0; i < nr_dt_cpu_features; i++) {
1087 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1088 
1089 		cpufeatures_deps_enable(f);
1090 	}
1091 
1092 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1093 	if (prop && strlen((char *)prop) != 0) {
1094 		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1095 		cur_cpu_spec->cpu_name = dt_cpu_name;
1096 	}
1097 
1098 	cpufeatures_setup_finished();
1099 
1100 	memblock_free(__pa(dt_cpu_features),
1101 			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1102 
1103 	return 0;
1104 }
1105 
1106 void __init dt_cpu_ftrs_scan(void)
1107 {
1108 	if (!using_dt_cpu_ftrs)
1109 		return;
1110 
1111 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1112 }
1113