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