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_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 extern long __machine_check_early_realmode_p8(struct pt_regs *regs);
68 extern long __machine_check_early_realmode_p9(struct pt_regs *regs);
69 extern long __machine_check_early_realmode_p10(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->mmu_features |= MMU_FTR_GTSE;
341 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
342 
343 	return 1;
344 #endif
345 	return 0;
346 }
347 
348 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
349 {
350 	u64 lpcr;
351 
352 	/*
353 	 * Linux relies on FSCR[DSCR] being clear, so that we can take the
354 	 * facility unavailable interrupt and track the task's usage of DSCR.
355 	 * See facility_unavailable_exception().
356 	 * Clear the bit here so that feat_enable() doesn't set it.
357 	 */
358 	f->fscr_bit_nr = -1;
359 
360 	feat_enable(f);
361 
362 	lpcr = mfspr(SPRN_LPCR);
363 	lpcr &= ~LPCR_DPFD;
364 	lpcr |=  (4UL << LPCR_DPFD_SH);
365 	mtspr(SPRN_LPCR, lpcr);
366 
367 	return 1;
368 }
369 
370 static void hfscr_pmu_enable(void)
371 {
372 	u64 hfscr = mfspr(SPRN_HFSCR);
373 	hfscr |= PPC_BIT(60);
374 	mtspr(SPRN_HFSCR, hfscr);
375 }
376 
377 static void init_pmu_power8(void)
378 {
379 	if (hv_mode) {
380 		mtspr(SPRN_MMCRC, 0);
381 		mtspr(SPRN_MMCRH, 0);
382 	}
383 
384 	mtspr(SPRN_MMCRA, 0);
385 	mtspr(SPRN_MMCR0, 0);
386 	mtspr(SPRN_MMCR1, 0);
387 	mtspr(SPRN_MMCR2, 0);
388 	mtspr(SPRN_MMCRS, 0);
389 }
390 
391 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
392 {
393 	cur_cpu_spec->platform = "power8";
394 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
395 
396 	return 1;
397 }
398 
399 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
400 {
401 	hfscr_pmu_enable();
402 
403 	init_pmu_power8();
404 	init_pmu_registers = init_pmu_power8;
405 
406 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
407 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
408 	if (pvr_version_is(PVR_POWER8E))
409 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
410 
411 	cur_cpu_spec->num_pmcs		= 6;
412 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
413 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
414 
415 	return 1;
416 }
417 
418 static void init_pmu_power9(void)
419 {
420 	if (hv_mode)
421 		mtspr(SPRN_MMCRC, 0);
422 
423 	mtspr(SPRN_MMCRA, 0);
424 	mtspr(SPRN_MMCR0, 0);
425 	mtspr(SPRN_MMCR1, 0);
426 	mtspr(SPRN_MMCR2, 0);
427 }
428 
429 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
430 {
431 	cur_cpu_spec->platform = "power9";
432 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
433 
434 	return 1;
435 }
436 
437 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
438 {
439 	hfscr_pmu_enable();
440 
441 	init_pmu_power9();
442 	init_pmu_registers = init_pmu_power9;
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 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
450 
451 	return 1;
452 }
453 
454 static void init_pmu_power10(void)
455 {
456 	init_pmu_power9();
457 
458 	mtspr(SPRN_MMCR3, 0);
459 	mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
460 }
461 
462 static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
463 {
464 	hfscr_pmu_enable();
465 
466 	init_pmu_power10();
467 	init_pmu_registers = init_pmu_power10;
468 
469 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
470 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
471 
472 	cur_cpu_spec->num_pmcs          = 6;
473 	cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
474 	cur_cpu_spec->oprofile_cpu_type = "ppc64/power10";
475 
476 	return 1;
477 }
478 
479 static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
480 {
481 	cur_cpu_spec->platform = "power10";
482 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
483 
484 	return 1;
485 }
486 
487 static int __init feat_enable_tm(struct dt_cpu_feature *f)
488 {
489 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
490 	feat_enable(f);
491 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
492 	return 1;
493 #endif
494 	return 0;
495 }
496 
497 static int __init feat_enable_fp(struct dt_cpu_feature *f)
498 {
499 	feat_enable(f);
500 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
501 
502 	return 1;
503 }
504 
505 static int __init feat_enable_vector(struct dt_cpu_feature *f)
506 {
507 #ifdef CONFIG_ALTIVEC
508 	feat_enable(f);
509 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
510 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
511 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
512 
513 	return 1;
514 #endif
515 	return 0;
516 }
517 
518 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
519 {
520 #ifdef CONFIG_VSX
521 	feat_enable(f);
522 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
523 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
524 
525 	return 1;
526 #endif
527 	return 0;
528 }
529 
530 static int __init feat_enable_purr(struct dt_cpu_feature *f)
531 {
532 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
533 
534 	return 1;
535 }
536 
537 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
538 {
539 	/*
540 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
541 	 * historically been related to the PMU facility. This may have
542 	 * to be decoupled if EBB becomes more generic. For now, follow
543 	 * existing convention.
544 	 */
545 	f->hwcap_bit_nr = -1;
546 	feat_enable(f);
547 
548 	return 1;
549 }
550 
551 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
552 {
553 	u64 lpcr;
554 
555 	/* P9 has an HFSCR for privileged state */
556 	feat_enable(f);
557 
558 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
559 
560 	lpcr = mfspr(SPRN_LPCR);
561 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
562 	mtspr(SPRN_LPCR, lpcr);
563 
564 	return 1;
565 }
566 
567 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
568 {
569 	u64 lpcr;
570 
571 	/*
572 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
573 	 * are always delivered as hypervisor virtualization interrupts (HVI)
574 	 * rather than EE.
575 	 *
576 	 * However LPES0 is not set here, in the chance that an EE does get
577 	 * delivered to the host somehow, the EE handler would not expect it
578 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
579 	 * happen if there is a bug in interrupt controller code, or IC is
580 	 * misconfigured in systemsim.
581 	 */
582 
583 	lpcr = mfspr(SPRN_LPCR);
584 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
585 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
586 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
587 	mtspr(SPRN_LPCR, lpcr);
588 
589 	return 1;
590 }
591 
592 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
593 {
594 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
595 
596 	return 1;
597 }
598 
599 static int __init feat_enable_mma(struct dt_cpu_feature *f)
600 {
601 	u64 pcr;
602 
603 	feat_enable(f);
604 	pcr = mfspr(SPRN_PCR);
605 	pcr &= ~PCR_MMA_DIS;
606 	mtspr(SPRN_PCR, pcr);
607 
608 	return 1;
609 }
610 
611 struct dt_cpu_feature_match {
612 	const char *name;
613 	int (*enable)(struct dt_cpu_feature *f);
614 	u64 cpu_ftr_bit_mask;
615 };
616 
617 static struct dt_cpu_feature_match __initdata
618 		dt_cpu_feature_match_table[] = {
619 	{"hypervisor", feat_enable_hv, 0},
620 	{"big-endian", feat_enable, 0},
621 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
622 	{"smt", feat_enable_smt, 0},
623 	{"interrupt-facilities", feat_enable, 0},
624 	{"system-call-vectored", feat_enable, 0},
625 	{"timer-facilities", feat_enable, 0},
626 	{"timer-facilities-v3", feat_enable, 0},
627 	{"debug-facilities", feat_enable, 0},
628 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
629 	{"branch-tracing", feat_enable, 0},
630 	{"floating-point", feat_enable_fp, 0},
631 	{"vector", feat_enable_vector, 0},
632 	{"vector-scalar", feat_enable_vsx, 0},
633 	{"vector-scalar-v3", feat_enable, 0},
634 	{"decimal-floating-point", feat_enable, 0},
635 	{"decimal-integer", feat_enable, 0},
636 	{"quadword-load-store", feat_enable, 0},
637 	{"vector-crypto", feat_enable, 0},
638 	{"mmu-hash", feat_enable_mmu_hash, 0},
639 	{"mmu-radix", feat_enable_mmu_radix, 0},
640 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
641 	{"virtual-page-class-key-protection", feat_enable, 0},
642 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
643 	{"transactional-memory-v3", feat_enable_tm, 0},
644 	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
645 	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
646 	{"idle-nap", feat_enable_idle_nap, 0},
647 	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
648 	{"idle-stop", feat_enable_idle_stop, 0},
649 	{"machine-check-power8", feat_enable_mce_power8, 0},
650 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
651 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
652 	{"event-based-branch", feat_enable_ebb, 0},
653 	{"target-address-register", feat_enable, 0},
654 	{"branch-history-rolling-buffer", feat_enable, 0},
655 	{"control-register", feat_enable, CPU_FTR_CTRL},
656 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
657 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
658 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
659 	{"no-execute", feat_enable, 0},
660 	/* strong-access-ordering is unused */
661 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
662 	{"coprocessor-icswx", feat_enable, 0},
663 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
664 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
665 	{"wait", feat_enable, 0},
666 	{"atomic-memory-operations", feat_enable, 0},
667 	{"branch-v3", feat_enable, 0},
668 	{"copy-paste", feat_enable, 0},
669 	{"decimal-floating-point-v3", feat_enable, 0},
670 	{"decimal-integer-v3", feat_enable, 0},
671 	{"fixed-point-v3", feat_enable, 0},
672 	{"floating-point-v3", feat_enable, 0},
673 	{"group-start-register", feat_enable, 0},
674 	{"pc-relative-addressing", feat_enable, 0},
675 	{"machine-check-power9", feat_enable_mce_power9, 0},
676 	{"machine-check-power10", feat_enable_mce_power10, 0},
677 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
678 	{"performance-monitor-power10", feat_enable_pmu_power10, 0},
679 	{"event-based-branch-v3", feat_enable, 0},
680 	{"random-number-generator", feat_enable, 0},
681 	{"system-call-vectored", feat_disable, 0},
682 	{"trace-interrupt-v3", feat_enable, 0},
683 	{"vector-v3", feat_enable, 0},
684 	{"vector-binary128", feat_enable, 0},
685 	{"vector-binary16", feat_enable, 0},
686 	{"wait-v3", feat_enable, 0},
687 	{"prefix-instructions", feat_enable, 0},
688 	{"matrix-multiply-assist", feat_enable_mma, 0},
689 	{"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
690 };
691 
692 static bool __initdata using_dt_cpu_ftrs;
693 static bool __initdata enable_unknown = true;
694 
695 static int __init dt_cpu_ftrs_parse(char *str)
696 {
697 	if (!str)
698 		return 0;
699 
700 	if (!strcmp(str, "off"))
701 		using_dt_cpu_ftrs = false;
702 	else if (!strcmp(str, "known"))
703 		enable_unknown = false;
704 	else
705 		return 1;
706 
707 	return 0;
708 }
709 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
710 
711 static void __init cpufeatures_setup_start(u32 isa)
712 {
713 	pr_info("setup for ISA %d\n", isa);
714 
715 	if (isa >= ISA_V3_0B) {
716 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
717 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
718 	}
719 
720 	if (isa >= ISA_V3_1) {
721 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
722 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
723 	}
724 }
725 
726 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
727 {
728 	const struct dt_cpu_feature_match *m;
729 	bool known = false;
730 	int i;
731 
732 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
733 		m = &dt_cpu_feature_match_table[i];
734 		if (!strcmp(f->name, m->name)) {
735 			known = true;
736 			if (m->enable(f)) {
737 				cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
738 				break;
739 			}
740 
741 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
742 				f->name);
743 			return false;
744 		}
745 	}
746 
747 	if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
748 		pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
749 			f->name);
750 		return false;
751 	}
752 
753 	if (known)
754 		pr_debug("enabling: %s\n", f->name);
755 	else
756 		pr_debug("enabling: %s (unknown)\n", f->name);
757 
758 	return true;
759 }
760 
761 /*
762  * Handle POWER9 broadcast tlbie invalidation issue using
763  * cpu feature flag.
764  */
765 static __init void update_tlbie_feature_flag(unsigned long pvr)
766 {
767 	if (PVR_VER(pvr) == PVR_POWER9) {
768 		/*
769 		 * Set the tlbie feature flag for anything below
770 		 * Nimbus DD 2.3 and Cumulus DD 1.3
771 		 */
772 		if ((pvr & 0xe000) == 0) {
773 			/* Nimbus */
774 			if ((pvr & 0xfff) < 0x203)
775 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
776 		} else if ((pvr & 0xc000) == 0) {
777 			/* Cumulus */
778 			if ((pvr & 0xfff) < 0x103)
779 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
780 		} else {
781 			WARN_ONCE(1, "Unknown PVR");
782 			cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
783 		}
784 
785 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
786 	}
787 }
788 
789 static __init void cpufeatures_cpu_quirks(void)
790 {
791 	unsigned long version = mfspr(SPRN_PVR);
792 
793 	/*
794 	 * Not all quirks can be derived from the cpufeatures device tree.
795 	 */
796 	if ((version & 0xffffefff) == 0x004e0200) {
797 		/* DD2.0 has no feature flag */
798 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
799 	} else if ((version & 0xffffefff) == 0x004e0201) {
800 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
801 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
802 	} else if ((version & 0xffffefff) == 0x004e0202) {
803 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
804 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
805 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
806 	} else if ((version & 0xffff0000) == 0x004e0000) {
807 		/* DD2.1 and up have DD2_1 */
808 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
809 	}
810 
811 	if ((version & 0xffff0000) == 0x004e0000) {
812 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
813 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
814 	}
815 
816 	update_tlbie_feature_flag(version);
817 }
818 
819 static void __init cpufeatures_setup_finished(void)
820 {
821 	cpufeatures_cpu_quirks();
822 
823 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
824 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
825 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
826 	}
827 
828 	/* Make sure powerpc_base_platform is non-NULL */
829 	powerpc_base_platform = cur_cpu_spec->platform;
830 
831 	system_registers.lpcr = mfspr(SPRN_LPCR);
832 	system_registers.hfscr = mfspr(SPRN_HFSCR);
833 	system_registers.fscr = mfspr(SPRN_FSCR);
834 	system_registers.pcr = mfspr(SPRN_PCR);
835 
836 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
837 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
838 }
839 
840 static int __init disabled_on_cmdline(void)
841 {
842 	unsigned long root, chosen;
843 	const char *p;
844 
845 	root = of_get_flat_dt_root();
846 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
847 	if (chosen == -FDT_ERR_NOTFOUND)
848 		return false;
849 
850 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
851 	if (!p)
852 		return false;
853 
854 	if (strstr(p, "dt_cpu_ftrs=off"))
855 		return true;
856 
857 	return false;
858 }
859 
860 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
861 					int depth, void *data)
862 {
863 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
864 	    && of_get_flat_dt_prop(node, "isa", NULL))
865 		return 1;
866 
867 	return 0;
868 }
869 
870 bool __init dt_cpu_ftrs_in_use(void)
871 {
872 	return using_dt_cpu_ftrs;
873 }
874 
875 bool __init dt_cpu_ftrs_init(void *fdt)
876 {
877 	using_dt_cpu_ftrs = false;
878 
879 	/* Setup and verify the FDT, if it fails we just bail */
880 	if (!early_init_dt_verify(fdt))
881 		return false;
882 
883 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
884 		return false;
885 
886 	if (disabled_on_cmdline())
887 		return false;
888 
889 	cpufeatures_setup_cpu();
890 
891 	using_dt_cpu_ftrs = true;
892 	return true;
893 }
894 
895 static int nr_dt_cpu_features;
896 static struct dt_cpu_feature *dt_cpu_features;
897 
898 static int __init process_cpufeatures_node(unsigned long node,
899 					  const char *uname, int i)
900 {
901 	const __be32 *prop;
902 	struct dt_cpu_feature *f;
903 	int len;
904 
905 	f = &dt_cpu_features[i];
906 
907 	f->node = node;
908 
909 	f->name = uname;
910 
911 	prop = of_get_flat_dt_prop(node, "isa", &len);
912 	if (!prop) {
913 		pr_warn("%s: missing isa property\n", uname);
914 		return 0;
915 	}
916 	f->isa = be32_to_cpup(prop);
917 
918 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
919 	if (!prop) {
920 		pr_warn("%s: missing usable-privilege property", uname);
921 		return 0;
922 	}
923 	f->usable_privilege = be32_to_cpup(prop);
924 
925 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
926 	if (prop)
927 		f->hv_support = be32_to_cpup(prop);
928 	else
929 		f->hv_support = HV_SUPPORT_NONE;
930 
931 	prop = of_get_flat_dt_prop(node, "os-support", &len);
932 	if (prop)
933 		f->os_support = be32_to_cpup(prop);
934 	else
935 		f->os_support = OS_SUPPORT_NONE;
936 
937 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
938 	if (prop)
939 		f->hfscr_bit_nr = be32_to_cpup(prop);
940 	else
941 		f->hfscr_bit_nr = -1;
942 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
943 	if (prop)
944 		f->fscr_bit_nr = be32_to_cpup(prop);
945 	else
946 		f->fscr_bit_nr = -1;
947 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
948 	if (prop)
949 		f->hwcap_bit_nr = be32_to_cpup(prop);
950 	else
951 		f->hwcap_bit_nr = -1;
952 
953 	if (f->usable_privilege & USABLE_HV) {
954 		if (!(mfmsr() & MSR_HV)) {
955 			pr_warn("%s: HV feature passed to guest\n", uname);
956 			return 0;
957 		}
958 
959 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
960 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
961 			return 0;
962 		}
963 
964 		if (f->hv_support == HV_SUPPORT_HFSCR) {
965 			if (f->hfscr_bit_nr == -1) {
966 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
967 				return 0;
968 			}
969 		}
970 	} else {
971 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
972 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
973 			return 0;
974 		}
975 	}
976 
977 	if (f->usable_privilege & USABLE_OS) {
978 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
979 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
980 			return 0;
981 		}
982 
983 		if (f->os_support == OS_SUPPORT_FSCR) {
984 			if (f->fscr_bit_nr == -1) {
985 				pr_warn("%s: missing fscr_bit_nr\n", uname);
986 				return 0;
987 			}
988 		}
989 	} else {
990 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
991 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
992 			return 0;
993 		}
994 	}
995 
996 	if (!(f->usable_privilege & USABLE_PR)) {
997 		if (f->hwcap_bit_nr != -1) {
998 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
999 			return 0;
1000 		}
1001 	}
1002 
1003 	/* Do all the independent features in the first pass */
1004 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
1005 		if (cpufeatures_process_feature(f))
1006 			f->enabled = 1;
1007 		else
1008 			f->disabled = 1;
1009 	}
1010 
1011 	return 0;
1012 }
1013 
1014 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
1015 {
1016 	const __be32 *prop;
1017 	int len;
1018 	int nr_deps;
1019 	int i;
1020 
1021 	if (f->enabled || f->disabled)
1022 		return;
1023 
1024 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
1025 	if (!prop) {
1026 		pr_warn("%s: missing dependencies property", f->name);
1027 		return;
1028 	}
1029 
1030 	nr_deps = len / sizeof(int);
1031 
1032 	for (i = 0; i < nr_deps; i++) {
1033 		unsigned long phandle = be32_to_cpu(prop[i]);
1034 		int j;
1035 
1036 		for (j = 0; j < nr_dt_cpu_features; j++) {
1037 			struct dt_cpu_feature *d = &dt_cpu_features[j];
1038 
1039 			if (of_get_flat_dt_phandle(d->node) == phandle) {
1040 				cpufeatures_deps_enable(d);
1041 				if (d->disabled) {
1042 					f->disabled = 1;
1043 					return;
1044 				}
1045 			}
1046 		}
1047 	}
1048 
1049 	if (cpufeatures_process_feature(f))
1050 		f->enabled = 1;
1051 	else
1052 		f->disabled = 1;
1053 }
1054 
1055 static int __init scan_cpufeatures_subnodes(unsigned long node,
1056 					  const char *uname,
1057 					  void *data)
1058 {
1059 	int *count = data;
1060 
1061 	process_cpufeatures_node(node, uname, *count);
1062 
1063 	(*count)++;
1064 
1065 	return 0;
1066 }
1067 
1068 static int __init count_cpufeatures_subnodes(unsigned long node,
1069 					  const char *uname,
1070 					  void *data)
1071 {
1072 	int *count = data;
1073 
1074 	(*count)++;
1075 
1076 	return 0;
1077 }
1078 
1079 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1080 					    *uname, int depth, void *data)
1081 {
1082 	const __be32 *prop;
1083 	int count, i;
1084 	u32 isa;
1085 
1086 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1087 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1088 		return 0;
1089 
1090 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1091 	if (!prop)
1092 		/* We checked before, "can't happen" */
1093 		return 0;
1094 
1095 	isa = be32_to_cpup(prop);
1096 
1097 	/* Count and allocate space for cpu features */
1098 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1099 						&nr_dt_cpu_features);
1100 	dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1101 	if (!dt_cpu_features)
1102 		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1103 		      __func__,
1104 		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1105 		      PAGE_SIZE);
1106 
1107 	cpufeatures_setup_start(isa);
1108 
1109 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1110 	count = 0;
1111 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1112 
1113 	/* Recursive enable remaining features with dependencies */
1114 	for (i = 0; i < nr_dt_cpu_features; i++) {
1115 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1116 
1117 		cpufeatures_deps_enable(f);
1118 	}
1119 
1120 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1121 	if (prop && strlen((char *)prop) != 0) {
1122 		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1123 		cur_cpu_spec->cpu_name = dt_cpu_name;
1124 	}
1125 
1126 	cpufeatures_setup_finished();
1127 
1128 	memblock_free(__pa(dt_cpu_features),
1129 			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1130 
1131 	return 0;
1132 }
1133 
1134 void __init dt_cpu_ftrs_scan(void)
1135 {
1136 	if (!using_dt_cpu_ftrs)
1137 		return;
1138 
1139 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1140 }
1141