xref: /linux/arch/powerpc/kernel/dt_cpu_ftrs.c (revision 594ce0b8a998aa4d05827cd7c0d0dcec9a1e3ae2)
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/of_fdt.h>
14 #include <linux/printk.h>
15 #include <linux/sched.h>
16 #include <linux/string.h>
17 #include <linux/threads.h>
18 
19 #include <asm/cputable.h>
20 #include <asm/dt_cpu_ftrs.h>
21 #include <asm/mce.h>
22 #include <asm/mmu.h>
23 #include <asm/setup.h>
24 
25 
26 /* Device-tree visible constants follow */
27 #define ISA_V3_0B       3000
28 #define ISA_V3_1        3100
29 
30 #define USABLE_PR               (1U << 0)
31 #define USABLE_OS               (1U << 1)
32 #define USABLE_HV               (1U << 2)
33 
34 #define HV_SUPPORT_HFSCR        (1U << 0)
35 #define OS_SUPPORT_FSCR         (1U << 0)
36 
37 /* For parsing, we define all bits set as "NONE" case */
38 #define HV_SUPPORT_NONE		0xffffffffU
39 #define OS_SUPPORT_NONE		0xffffffffU
40 
41 struct dt_cpu_feature {
42 	const char *name;
43 	uint32_t isa;
44 	uint32_t usable_privilege;
45 	uint32_t hv_support;
46 	uint32_t os_support;
47 	uint32_t hfscr_bit_nr;
48 	uint32_t fscr_bit_nr;
49 	uint32_t hwcap_bit_nr;
50 	/* fdt parsing */
51 	unsigned long node;
52 	int enabled;
53 	int disabled;
54 };
55 
56 #define 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 
67 static int hv_mode;
68 
69 static struct {
70 	u64	lpcr;
71 	u64	hfscr;
72 	u64	fscr;
73 	u64	pcr;
74 } system_registers;
75 
76 static void (*init_pmu_registers)(void);
77 
78 static void __restore_cpu_cpufeatures(void)
79 {
80 	mtspr(SPRN_LPCR, system_registers.lpcr);
81 	if (hv_mode) {
82 		mtspr(SPRN_LPID, 0);
83 		mtspr(SPRN_AMOR, ~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 	.cpu_setup		= NULL,
106 	.cpu_restore		= __restore_cpu_cpufeatures,
107 	.machine_check_early	= NULL,
108 	.platform		= NULL,
109 };
110 
111 static void __init cpufeatures_setup_cpu(void)
112 {
113 	set_cur_cpu_spec(&base_cpu_spec);
114 
115 	cur_cpu_spec->pvr_mask = -1;
116 	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
117 
118 	/* Initialize the base environment -- clear FSCR/HFSCR.  */
119 	hv_mode = !!(mfmsr() & MSR_HV);
120 	if (hv_mode) {
121 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
122 		mtspr(SPRN_HFSCR, 0);
123 	}
124 	mtspr(SPRN_FSCR, 0);
125 	mtspr(SPRN_PCR, PCR_MASK);
126 
127 	/*
128 	 * LPCR does not get cleared, to match behaviour with secondaries
129 	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
130 	 * could clear LPCR too.
131 	 */
132 }
133 
134 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
135 {
136 	if (f->hv_support == HV_SUPPORT_NONE) {
137 	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
138 		u64 hfscr = mfspr(SPRN_HFSCR);
139 		hfscr |= 1UL << f->hfscr_bit_nr;
140 		mtspr(SPRN_HFSCR, hfscr);
141 	} else {
142 		/* Does not have a known recipe */
143 		return 0;
144 	}
145 
146 	if (f->os_support == OS_SUPPORT_NONE) {
147 	} else if (f->os_support & OS_SUPPORT_FSCR) {
148 		u64 fscr = mfspr(SPRN_FSCR);
149 		fscr |= 1UL << f->fscr_bit_nr;
150 		mtspr(SPRN_FSCR, fscr);
151 	} else {
152 		/* Does not have a known recipe */
153 		return 0;
154 	}
155 
156 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
157 		uint32_t word = f->hwcap_bit_nr / 32;
158 		uint32_t bit = f->hwcap_bit_nr % 32;
159 
160 		if (word == 0)
161 			cur_cpu_spec->cpu_user_features |= 1U << bit;
162 		else if (word == 1)
163 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
164 		else
165 			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
166 	}
167 
168 	return 1;
169 }
170 
171 static int __init feat_enable(struct dt_cpu_feature *f)
172 {
173 	if (f->hv_support != HV_SUPPORT_NONE) {
174 		if (f->hfscr_bit_nr != -1) {
175 			u64 hfscr = mfspr(SPRN_HFSCR);
176 			hfscr |= 1UL << f->hfscr_bit_nr;
177 			mtspr(SPRN_HFSCR, hfscr);
178 		}
179 	}
180 
181 	if (f->os_support != OS_SUPPORT_NONE) {
182 		if (f->fscr_bit_nr != -1) {
183 			u64 fscr = mfspr(SPRN_FSCR);
184 			fscr |= 1UL << f->fscr_bit_nr;
185 			mtspr(SPRN_FSCR, fscr);
186 		}
187 	}
188 
189 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
190 		uint32_t word = f->hwcap_bit_nr / 32;
191 		uint32_t bit = f->hwcap_bit_nr % 32;
192 
193 		if (word == 0)
194 			cur_cpu_spec->cpu_user_features |= 1U << bit;
195 		else if (word == 1)
196 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
197 		else
198 			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
199 	}
200 
201 	return 1;
202 }
203 
204 static int __init feat_disable(struct dt_cpu_feature *f)
205 {
206 	return 0;
207 }
208 
209 static int __init feat_enable_hv(struct dt_cpu_feature *f)
210 {
211 	u64 lpcr;
212 
213 	if (!hv_mode) {
214 		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
215 		return 0;
216 	}
217 
218 	mtspr(SPRN_LPID, 0);
219 	mtspr(SPRN_AMOR, ~0);
220 
221 	lpcr = mfspr(SPRN_LPCR);
222 	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
223 	mtspr(SPRN_LPCR, lpcr);
224 
225 	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
226 
227 	return 1;
228 }
229 
230 static int __init feat_enable_le(struct dt_cpu_feature *f)
231 {
232 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
233 	return 1;
234 }
235 
236 static int __init feat_enable_smt(struct dt_cpu_feature *f)
237 {
238 	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
239 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
240 	return 1;
241 }
242 
243 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
244 {
245 	u64 lpcr;
246 
247 	/* Set PECE wakeup modes for ISA 207 */
248 	lpcr = mfspr(SPRN_LPCR);
249 	lpcr |=  LPCR_PECE0;
250 	lpcr |=  LPCR_PECE1;
251 	lpcr |=  LPCR_PECE2;
252 	mtspr(SPRN_LPCR, lpcr);
253 
254 	return 1;
255 }
256 
257 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
258 {
259 	u64 lpcr;
260 
261 	/* Set PECE wakeup modes for ISAv3.0B */
262 	lpcr = mfspr(SPRN_LPCR);
263 	lpcr |=  LPCR_PECE0;
264 	lpcr |=  LPCR_PECE1;
265 	lpcr |=  LPCR_PECE2;
266 	mtspr(SPRN_LPCR, lpcr);
267 
268 	return 1;
269 }
270 
271 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
272 {
273 	u64 lpcr;
274 
275 	if (!IS_ENABLED(CONFIG_PPC_64S_HASH_MMU))
276 		return 0;
277 
278 	lpcr = mfspr(SPRN_LPCR);
279 	lpcr &= ~LPCR_ISL;
280 
281 	/* VRMASD */
282 	lpcr |= LPCR_VPM0;
283 	lpcr &= ~LPCR_VPM1;
284 	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
285 	mtspr(SPRN_LPCR, lpcr);
286 
287 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
288 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
289 
290 	return 1;
291 }
292 
293 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
294 {
295 	u64 lpcr;
296 
297 	if (!IS_ENABLED(CONFIG_PPC_64S_HASH_MMU))
298 		return 0;
299 
300 	lpcr = mfspr(SPRN_LPCR);
301 	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
302 	mtspr(SPRN_LPCR, lpcr);
303 
304 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
305 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
306 
307 	return 1;
308 }
309 
310 
311 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
312 {
313 	if (!IS_ENABLED(CONFIG_PPC_RADIX_MMU))
314 		return 0;
315 
316 	cur_cpu_spec->mmu_features |= MMU_FTR_KERNEL_RO;
317 	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
318 	cur_cpu_spec->mmu_features |= MMU_FTR_GTSE;
319 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
320 
321 	return 1;
322 }
323 
324 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
325 {
326 	u64 lpcr;
327 
328 	/*
329 	 * Linux relies on FSCR[DSCR] being clear, so that we can take the
330 	 * facility unavailable interrupt and track the task's usage of DSCR.
331 	 * See facility_unavailable_exception().
332 	 * Clear the bit here so that feat_enable() doesn't set it.
333 	 */
334 	f->fscr_bit_nr = -1;
335 
336 	feat_enable(f);
337 
338 	lpcr = mfspr(SPRN_LPCR);
339 	lpcr &= ~LPCR_DPFD;
340 	lpcr |=  (4UL << LPCR_DPFD_SH);
341 	mtspr(SPRN_LPCR, lpcr);
342 
343 	return 1;
344 }
345 
346 static void __init hfscr_pmu_enable(void)
347 {
348 	u64 hfscr = mfspr(SPRN_HFSCR);
349 	hfscr |= PPC_BIT(60);
350 	mtspr(SPRN_HFSCR, hfscr);
351 }
352 
353 static void init_pmu_power8(void)
354 {
355 	if (hv_mode) {
356 		mtspr(SPRN_MMCRC, 0);
357 		mtspr(SPRN_MMCRH, 0);
358 	}
359 
360 	mtspr(SPRN_MMCRA, 0);
361 	mtspr(SPRN_MMCR0, MMCR0_FC);
362 	mtspr(SPRN_MMCR1, 0);
363 	mtspr(SPRN_MMCR2, 0);
364 	mtspr(SPRN_MMCRS, 0);
365 }
366 
367 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
368 {
369 	cur_cpu_spec->platform = "power8";
370 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
371 
372 	return 1;
373 }
374 
375 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
376 {
377 	hfscr_pmu_enable();
378 
379 	init_pmu_power8();
380 	init_pmu_registers = init_pmu_power8;
381 
382 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
383 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
384 	if (pvr_version_is(PVR_POWER8E))
385 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
386 
387 	cur_cpu_spec->num_pmcs		= 6;
388 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
389 
390 	return 1;
391 }
392 
393 static void init_pmu_power9(void)
394 {
395 	if (hv_mode)
396 		mtspr(SPRN_MMCRC, 0);
397 
398 	mtspr(SPRN_MMCRA, 0);
399 	mtspr(SPRN_MMCR0, MMCR0_FC);
400 	mtspr(SPRN_MMCR1, 0);
401 	mtspr(SPRN_MMCR2, 0);
402 }
403 
404 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
405 {
406 	cur_cpu_spec->platform = "power9";
407 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
408 
409 	return 1;
410 }
411 
412 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
413 {
414 	hfscr_pmu_enable();
415 
416 	init_pmu_power9();
417 	init_pmu_registers = init_pmu_power9;
418 
419 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
420 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
421 
422 	cur_cpu_spec->num_pmcs		= 6;
423 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
424 
425 	return 1;
426 }
427 
428 static void init_pmu_power10(void)
429 {
430 	init_pmu_power9();
431 
432 	mtspr(SPRN_MMCR3, 0);
433 	mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
434 	mtspr(SPRN_MMCR0, MMCR0_FC | MMCR0_PMCCEXT);
435 }
436 
437 static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
438 {
439 	hfscr_pmu_enable();
440 
441 	init_pmu_power10();
442 	init_pmu_registers = init_pmu_power10;
443 
444 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
445 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
446 
447 	cur_cpu_spec->num_pmcs          = 6;
448 	cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
449 
450 	return 1;
451 }
452 
453 static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
454 {
455 	cur_cpu_spec->platform = "power10";
456 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
457 
458 	return 1;
459 }
460 
461 static int __init feat_enable_mce_power11(struct dt_cpu_feature *f)
462 {
463 	cur_cpu_spec->platform = "power11";
464 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
465 
466 	return 1;
467 }
468 
469 static int __init feat_enable_tm(struct dt_cpu_feature *f)
470 {
471 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
472 	feat_enable(f);
473 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
474 	return 1;
475 #endif
476 	return 0;
477 }
478 
479 static int __init feat_enable_fp(struct dt_cpu_feature *f)
480 {
481 	feat_enable(f);
482 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
483 
484 	return 1;
485 }
486 
487 static int __init feat_enable_vector(struct dt_cpu_feature *f)
488 {
489 #ifdef CONFIG_ALTIVEC
490 	feat_enable(f);
491 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
492 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
493 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
494 
495 	return 1;
496 #endif
497 	return 0;
498 }
499 
500 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
501 {
502 #ifdef CONFIG_VSX
503 	feat_enable(f);
504 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
505 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
506 
507 	return 1;
508 #endif
509 	return 0;
510 }
511 
512 static int __init feat_enable_purr(struct dt_cpu_feature *f)
513 {
514 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
515 
516 	return 1;
517 }
518 
519 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
520 {
521 	/*
522 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
523 	 * historically been related to the PMU facility. This may have
524 	 * to be decoupled if EBB becomes more generic. For now, follow
525 	 * existing convention.
526 	 */
527 	f->hwcap_bit_nr = -1;
528 	feat_enable(f);
529 
530 	return 1;
531 }
532 
533 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
534 {
535 	u64 lpcr;
536 
537 	/* P9 has an HFSCR for privileged state */
538 	feat_enable(f);
539 
540 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
541 
542 	lpcr = mfspr(SPRN_LPCR);
543 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
544 	mtspr(SPRN_LPCR, lpcr);
545 
546 	return 1;
547 }
548 
549 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
550 {
551 	u64 lpcr;
552 
553 	/*
554 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
555 	 * are always delivered as hypervisor virtualization interrupts (HVI)
556 	 * rather than EE.
557 	 *
558 	 * However LPES0 is not set here, in the chance that an EE does get
559 	 * delivered to the host somehow, the EE handler would not expect it
560 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
561 	 * happen if there is a bug in interrupt controller code, or IC is
562 	 * misconfigured in systemsim.
563 	 */
564 
565 	lpcr = mfspr(SPRN_LPCR);
566 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
567 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
568 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
569 	mtspr(SPRN_LPCR, lpcr);
570 
571 	return 1;
572 }
573 
574 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
575 {
576 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
577 
578 	return 1;
579 }
580 
581 static int __init feat_enable_mma(struct dt_cpu_feature *f)
582 {
583 	u64 pcr;
584 
585 	feat_enable(f);
586 	pcr = mfspr(SPRN_PCR);
587 	pcr &= ~PCR_MMA_DIS;
588 	mtspr(SPRN_PCR, pcr);
589 
590 	return 1;
591 }
592 
593 struct dt_cpu_feature_match {
594 	const char *name;
595 	int (*enable)(struct dt_cpu_feature *f);
596 	u64 cpu_ftr_bit_mask;
597 };
598 
599 static struct dt_cpu_feature_match __initdata
600 		dt_cpu_feature_match_table[] = {
601 	{"hypervisor", feat_enable_hv, 0},
602 	{"big-endian", feat_enable, 0},
603 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
604 	{"smt", feat_enable_smt, 0},
605 	{"interrupt-facilities", feat_enable, 0},
606 	{"system-call-vectored", feat_enable, 0},
607 	{"timer-facilities", feat_enable, 0},
608 	{"timer-facilities-v3", feat_enable, 0},
609 	{"debug-facilities", feat_enable, 0},
610 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
611 	{"branch-tracing", feat_enable, 0},
612 	{"floating-point", feat_enable_fp, 0},
613 	{"vector", feat_enable_vector, 0},
614 	{"vector-scalar", feat_enable_vsx, 0},
615 	{"vector-scalar-v3", feat_enable, 0},
616 	{"decimal-floating-point", feat_enable, 0},
617 	{"decimal-integer", feat_enable, 0},
618 	{"quadword-load-store", feat_enable, 0},
619 	{"vector-crypto", feat_enable, 0},
620 	{"mmu-hash", feat_enable_mmu_hash, 0},
621 	{"mmu-radix", feat_enable_mmu_radix, 0},
622 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
623 	{"virtual-page-class-key-protection", feat_enable, 0},
624 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
625 	{"transactional-memory-v3", feat_enable_tm, 0},
626 	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
627 	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
628 	{"idle-nap", feat_enable_idle_nap, 0},
629 	/* alignment-interrupt-dsisr ignored */
630 	{"idle-stop", feat_enable_idle_stop, 0},
631 	{"machine-check-power8", feat_enable_mce_power8, 0},
632 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
633 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
634 	{"event-based-branch", feat_enable_ebb, 0},
635 	{"target-address-register", feat_enable, 0},
636 	{"branch-history-rolling-buffer", feat_enable, 0},
637 	{"control-register", feat_enable, CPU_FTR_CTRL},
638 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
639 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
640 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
641 	{"no-execute", feat_enable, 0},
642 	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
643 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
644 	{"coprocessor-icswx", feat_enable, 0},
645 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
646 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
647 	{"wait", feat_enable, 0},
648 	{"atomic-memory-operations", feat_enable, 0},
649 	{"branch-v3", feat_enable, 0},
650 	{"copy-paste", feat_enable, 0},
651 	{"decimal-floating-point-v3", feat_enable, 0},
652 	{"decimal-integer-v3", feat_enable, 0},
653 	{"fixed-point-v3", feat_enable, 0},
654 	{"floating-point-v3", feat_enable, 0},
655 	{"group-start-register", feat_enable, 0},
656 	{"pc-relative-addressing", feat_enable, 0},
657 	{"machine-check-power9", feat_enable_mce_power9, 0},
658 	{"machine-check-power10", feat_enable_mce_power10, 0},
659 	{"machine-check-power11", feat_enable_mce_power11, 0},
660 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
661 	{"performance-monitor-power10", feat_enable_pmu_power10, 0},
662 	{"performance-monitor-power11", feat_enable_pmu_power10, 0},
663 	{"event-based-branch-v3", feat_enable, 0},
664 	{"random-number-generator", feat_enable, 0},
665 	{"system-call-vectored", feat_disable, 0},
666 	{"trace-interrupt-v3", feat_enable, 0},
667 	{"vector-v3", feat_enable, 0},
668 	{"vector-binary128", feat_enable, 0},
669 	{"vector-binary16", feat_enable, 0},
670 	{"wait-v3", feat_enable, 0},
671 	{"prefix-instructions", feat_enable, 0},
672 	{"matrix-multiply-assist", feat_enable_mma, 0},
673 	{"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
674 };
675 
676 static bool __initdata using_dt_cpu_ftrs;
677 static bool __initdata enable_unknown = true;
678 
679 static int __init dt_cpu_ftrs_parse(char *str)
680 {
681 	if (!str)
682 		return 0;
683 
684 	if (!strcmp(str, "off"))
685 		using_dt_cpu_ftrs = false;
686 	else if (!strcmp(str, "known"))
687 		enable_unknown = false;
688 	else
689 		return 1;
690 
691 	return 0;
692 }
693 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
694 
695 static void __init cpufeatures_setup_start(u32 isa)
696 {
697 	pr_info("setup for ISA %d\n", isa);
698 
699 	if (isa >= ISA_V3_0B) {
700 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
701 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
702 	}
703 
704 	if (isa >= ISA_V3_1) {
705 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
706 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
707 	}
708 }
709 
710 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
711 {
712 	const struct dt_cpu_feature_match *m;
713 	bool known = false;
714 	int i;
715 
716 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
717 		m = &dt_cpu_feature_match_table[i];
718 		if (!strcmp(f->name, m->name)) {
719 			known = true;
720 			if (m->enable(f)) {
721 				cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
722 				break;
723 			}
724 
725 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
726 				f->name);
727 			return false;
728 		}
729 	}
730 
731 	if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
732 		pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
733 			f->name);
734 		return false;
735 	}
736 
737 	if (known)
738 		pr_debug("enabling: %s\n", f->name);
739 	else
740 		pr_debug("enabling: %s (unknown)\n", f->name);
741 
742 	return true;
743 }
744 
745 /*
746  * Handle POWER9 broadcast tlbie invalidation issue using
747  * cpu feature flag.
748  */
749 static __init void update_tlbie_feature_flag(unsigned long pvr)
750 {
751 	if (PVR_VER(pvr) == PVR_POWER9) {
752 		/*
753 		 * Set the tlbie feature flag for anything below
754 		 * Nimbus DD 2.3 and Cumulus DD 1.3
755 		 */
756 		if ((pvr & 0xe000) == 0) {
757 			/* Nimbus */
758 			if ((pvr & 0xfff) < 0x203)
759 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
760 		} else if ((pvr & 0xc000) == 0) {
761 			/* Cumulus */
762 			if ((pvr & 0xfff) < 0x103)
763 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
764 		} else {
765 			WARN_ONCE(1, "Unknown PVR");
766 			cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
767 		}
768 
769 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
770 	}
771 }
772 
773 static __init void cpufeatures_cpu_quirks(void)
774 {
775 	unsigned long version = mfspr(SPRN_PVR);
776 
777 	/*
778 	 * Not all quirks can be derived from the cpufeatures device tree.
779 	 */
780 	if ((version & 0xffffefff) == 0x004e0200) {
781 		/* DD2.0 has no feature flag */
782 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
783 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
784 	} else if ((version & 0xffffefff) == 0x004e0201) {
785 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
786 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
787 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
788 	} else if ((version & 0xffffefff) == 0x004e0202) {
789 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
790 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
791 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
792 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
793 	} else if ((version & 0xffffefff) == 0x004e0203) {
794 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
795 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
796 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
797 	} else if ((version & 0xffff0000) == 0x004e0000) {
798 		/* DD2.1 and up have DD2_1 */
799 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
800 	}
801 
802 	if ((version & 0xffff0000) == 0x004e0000) {
803 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
804 	}
805 
806 	update_tlbie_feature_flag(version);
807 }
808 
809 static void __init cpufeatures_setup_finished(void)
810 {
811 	cpufeatures_cpu_quirks();
812 
813 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
814 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
815 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
816 	}
817 
818 	/* Make sure powerpc_base_platform is non-NULL */
819 	powerpc_base_platform = cur_cpu_spec->platform;
820 
821 	system_registers.lpcr = mfspr(SPRN_LPCR);
822 	system_registers.hfscr = mfspr(SPRN_HFSCR);
823 	system_registers.fscr = mfspr(SPRN_FSCR);
824 	system_registers.pcr = mfspr(SPRN_PCR);
825 
826 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
827 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
828 }
829 
830 static int __init disabled_on_cmdline(void)
831 {
832 	unsigned long root, chosen;
833 	const char *p;
834 
835 	root = of_get_flat_dt_root();
836 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
837 	if (chosen == -FDT_ERR_NOTFOUND)
838 		return false;
839 
840 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
841 	if (!p)
842 		return false;
843 
844 	if (strstr(p, "dt_cpu_ftrs=off"))
845 		return true;
846 
847 	return false;
848 }
849 
850 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
851 					int depth, void *data)
852 {
853 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
854 	    && of_get_flat_dt_prop(node, "isa", NULL))
855 		return 1;
856 
857 	return 0;
858 }
859 
860 bool __init dt_cpu_ftrs_in_use(void)
861 {
862 	return using_dt_cpu_ftrs;
863 }
864 
865 bool __init dt_cpu_ftrs_init(void *fdt)
866 {
867 	using_dt_cpu_ftrs = false;
868 
869 	/* Setup and verify the FDT, if it fails we just bail */
870 	if (!early_init_dt_verify(fdt))
871 		return false;
872 
873 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
874 		return false;
875 
876 	if (disabled_on_cmdline())
877 		return false;
878 
879 	cpufeatures_setup_cpu();
880 
881 	using_dt_cpu_ftrs = true;
882 	return true;
883 }
884 
885 static int nr_dt_cpu_features;
886 static struct dt_cpu_feature *dt_cpu_features;
887 
888 static int __init process_cpufeatures_node(unsigned long node,
889 					  const char *uname, int i)
890 {
891 	const __be32 *prop;
892 	struct dt_cpu_feature *f;
893 	int len;
894 
895 	f = &dt_cpu_features[i];
896 
897 	f->node = node;
898 
899 	f->name = uname;
900 
901 	prop = of_get_flat_dt_prop(node, "isa", &len);
902 	if (!prop) {
903 		pr_warn("%s: missing isa property\n", uname);
904 		return 0;
905 	}
906 	f->isa = be32_to_cpup(prop);
907 
908 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
909 	if (!prop) {
910 		pr_warn("%s: missing usable-privilege property", uname);
911 		return 0;
912 	}
913 	f->usable_privilege = be32_to_cpup(prop);
914 
915 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
916 	if (prop)
917 		f->hv_support = be32_to_cpup(prop);
918 	else
919 		f->hv_support = HV_SUPPORT_NONE;
920 
921 	prop = of_get_flat_dt_prop(node, "os-support", &len);
922 	if (prop)
923 		f->os_support = be32_to_cpup(prop);
924 	else
925 		f->os_support = OS_SUPPORT_NONE;
926 
927 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
928 	if (prop)
929 		f->hfscr_bit_nr = be32_to_cpup(prop);
930 	else
931 		f->hfscr_bit_nr = -1;
932 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
933 	if (prop)
934 		f->fscr_bit_nr = be32_to_cpup(prop);
935 	else
936 		f->fscr_bit_nr = -1;
937 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
938 	if (prop)
939 		f->hwcap_bit_nr = be32_to_cpup(prop);
940 	else
941 		f->hwcap_bit_nr = -1;
942 
943 	if (f->usable_privilege & USABLE_HV) {
944 		if (!(mfmsr() & MSR_HV)) {
945 			pr_warn("%s: HV feature passed to guest\n", uname);
946 			return 0;
947 		}
948 
949 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
950 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
951 			return 0;
952 		}
953 
954 		if (f->hv_support == HV_SUPPORT_HFSCR) {
955 			if (f->hfscr_bit_nr == -1) {
956 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
957 				return 0;
958 			}
959 		}
960 	} else {
961 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
962 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
963 			return 0;
964 		}
965 	}
966 
967 	if (f->usable_privilege & USABLE_OS) {
968 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
969 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
970 			return 0;
971 		}
972 
973 		if (f->os_support == OS_SUPPORT_FSCR) {
974 			if (f->fscr_bit_nr == -1) {
975 				pr_warn("%s: missing fscr_bit_nr\n", uname);
976 				return 0;
977 			}
978 		}
979 	} else {
980 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
981 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
982 			return 0;
983 		}
984 	}
985 
986 	if (!(f->usable_privilege & USABLE_PR)) {
987 		if (f->hwcap_bit_nr != -1) {
988 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
989 			return 0;
990 		}
991 	}
992 
993 	/* Do all the independent features in the first pass */
994 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
995 		if (cpufeatures_process_feature(f))
996 			f->enabled = 1;
997 		else
998 			f->disabled = 1;
999 	}
1000 
1001 	return 0;
1002 }
1003 
1004 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
1005 {
1006 	const __be32 *prop;
1007 	int len;
1008 	int nr_deps;
1009 	int i;
1010 
1011 	if (f->enabled || f->disabled)
1012 		return;
1013 
1014 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
1015 	if (!prop) {
1016 		pr_warn("%s: missing dependencies property", f->name);
1017 		return;
1018 	}
1019 
1020 	nr_deps = len / sizeof(int);
1021 
1022 	for (i = 0; i < nr_deps; i++) {
1023 		unsigned long phandle = be32_to_cpu(prop[i]);
1024 		int j;
1025 
1026 		for (j = 0; j < nr_dt_cpu_features; j++) {
1027 			struct dt_cpu_feature *d = &dt_cpu_features[j];
1028 
1029 			if (of_get_flat_dt_phandle(d->node) == phandle) {
1030 				cpufeatures_deps_enable(d);
1031 				if (d->disabled) {
1032 					f->disabled = 1;
1033 					return;
1034 				}
1035 			}
1036 		}
1037 	}
1038 
1039 	if (cpufeatures_process_feature(f))
1040 		f->enabled = 1;
1041 	else
1042 		f->disabled = 1;
1043 }
1044 
1045 static int __init scan_cpufeatures_subnodes(unsigned long node,
1046 					  const char *uname,
1047 					  void *data)
1048 {
1049 	int *count = data;
1050 
1051 	process_cpufeatures_node(node, uname, *count);
1052 
1053 	(*count)++;
1054 
1055 	return 0;
1056 }
1057 
1058 static int __init count_cpufeatures_subnodes(unsigned long node,
1059 					  const char *uname,
1060 					  void *data)
1061 {
1062 	int *count = data;
1063 
1064 	(*count)++;
1065 
1066 	return 0;
1067 }
1068 
1069 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1070 					    *uname, int depth, void *data)
1071 {
1072 	const __be32 *prop;
1073 	int count, i;
1074 	u32 isa;
1075 
1076 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1077 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1078 		return 0;
1079 
1080 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1081 	if (!prop)
1082 		/* We checked before, "can't happen" */
1083 		return 0;
1084 
1085 	isa = be32_to_cpup(prop);
1086 
1087 	/* Count and allocate space for cpu features */
1088 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1089 						&nr_dt_cpu_features);
1090 	dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1091 	if (!dt_cpu_features)
1092 		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1093 		      __func__,
1094 		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1095 		      PAGE_SIZE);
1096 
1097 	cpufeatures_setup_start(isa);
1098 
1099 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1100 	count = 0;
1101 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1102 
1103 	/* Recursive enable remaining features with dependencies */
1104 	for (i = 0; i < nr_dt_cpu_features; i++) {
1105 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1106 
1107 		cpufeatures_deps_enable(f);
1108 	}
1109 
1110 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1111 	if (prop && strlen((char *)prop) != 0) {
1112 		strscpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1113 		cur_cpu_spec->cpu_name = dt_cpu_name;
1114 	}
1115 
1116 	cpufeatures_setup_finished();
1117 
1118 	memblock_free(dt_cpu_features,
1119 		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features);
1120 
1121 	return 0;
1122 }
1123 
1124 void __init dt_cpu_ftrs_scan(void)
1125 {
1126 	if (!using_dt_cpu_ftrs)
1127 		return;
1128 
1129 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1130 }
1131