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 static int hv_mode;
68 
69 static struct {
70 	u64	lpcr;
71 	u64	lpcr_clear;
72 	u64	hfscr;
73 	u64	fscr;
74 	u64	pcr;
75 } system_registers;
76 
77 static void (*init_pmu_registers)(void);
78 
79 static void __restore_cpu_cpufeatures(void)
80 {
81 	u64 lpcr;
82 
83 	/*
84 	 * LPCR is restored by the power on engine already. It can be changed
85 	 * after early init e.g., by radix enable, and we have no unified API
86 	 * for saving and restoring such SPRs.
87 	 *
88 	 * This ->restore hook should really be removed from idle and register
89 	 * restore moved directly into the idle restore code, because this code
90 	 * doesn't know how idle is implemented or what it needs restored here.
91 	 *
92 	 * The best we can do to accommodate secondary boot and idle restore
93 	 * for now is "or" LPCR with existing.
94 	 */
95 	lpcr = mfspr(SPRN_LPCR);
96 	lpcr |= system_registers.lpcr;
97 	lpcr &= ~system_registers.lpcr_clear;
98 	mtspr(SPRN_LPCR, lpcr);
99 	if (hv_mode) {
100 		mtspr(SPRN_LPID, 0);
101 		mtspr(SPRN_HFSCR, system_registers.hfscr);
102 		mtspr(SPRN_PCR, system_registers.pcr);
103 	}
104 	mtspr(SPRN_FSCR, system_registers.fscr);
105 
106 	if (init_pmu_registers)
107 		init_pmu_registers();
108 }
109 
110 static char dt_cpu_name[64];
111 
112 static struct cpu_spec __initdata base_cpu_spec = {
113 	.cpu_name		= NULL,
114 	.cpu_features		= CPU_FTRS_DT_CPU_BASE,
115 	.cpu_user_features	= COMMON_USER_BASE,
116 	.cpu_user_features2	= COMMON_USER2_BASE,
117 	.mmu_features		= 0,
118 	.icache_bsize		= 32, /* minimum block size, fixed by */
119 	.dcache_bsize		= 32, /* cache info init.             */
120 	.num_pmcs		= 0,
121 	.pmc_type		= PPC_PMC_DEFAULT,
122 	.oprofile_cpu_type	= NULL,
123 	.oprofile_type		= PPC_OPROFILE_INVALID,
124 	.cpu_setup		= NULL,
125 	.cpu_restore		= __restore_cpu_cpufeatures,
126 	.machine_check_early	= NULL,
127 	.platform		= NULL,
128 };
129 
130 static void __init cpufeatures_setup_cpu(void)
131 {
132 	set_cur_cpu_spec(&base_cpu_spec);
133 
134 	cur_cpu_spec->pvr_mask = -1;
135 	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
136 
137 	/* Initialize the base environment -- clear FSCR/HFSCR.  */
138 	hv_mode = !!(mfmsr() & MSR_HV);
139 	if (hv_mode) {
140 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
141 		mtspr(SPRN_HFSCR, 0);
142 	}
143 	mtspr(SPRN_FSCR, 0);
144 	mtspr(SPRN_PCR, PCR_MASK);
145 
146 	/*
147 	 * LPCR does not get cleared, to match behaviour with secondaries
148 	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
149 	 * could clear LPCR too.
150 	 */
151 }
152 
153 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
154 {
155 	if (f->hv_support == HV_SUPPORT_NONE) {
156 	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
157 		u64 hfscr = mfspr(SPRN_HFSCR);
158 		hfscr |= 1UL << f->hfscr_bit_nr;
159 		mtspr(SPRN_HFSCR, hfscr);
160 	} else {
161 		/* Does not have a known recipe */
162 		return 0;
163 	}
164 
165 	if (f->os_support == OS_SUPPORT_NONE) {
166 	} else if (f->os_support & OS_SUPPORT_FSCR) {
167 		u64 fscr = mfspr(SPRN_FSCR);
168 		fscr |= 1UL << f->fscr_bit_nr;
169 		mtspr(SPRN_FSCR, fscr);
170 	} else {
171 		/* Does not have a known recipe */
172 		return 0;
173 	}
174 
175 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
176 		uint32_t word = f->hwcap_bit_nr / 32;
177 		uint32_t bit = f->hwcap_bit_nr % 32;
178 
179 		if (word == 0)
180 			cur_cpu_spec->cpu_user_features |= 1U << bit;
181 		else if (word == 1)
182 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
183 		else
184 			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
185 	}
186 
187 	return 1;
188 }
189 
190 static int __init feat_enable(struct dt_cpu_feature *f)
191 {
192 	if (f->hv_support != HV_SUPPORT_NONE) {
193 		if (f->hfscr_bit_nr != -1) {
194 			u64 hfscr = mfspr(SPRN_HFSCR);
195 			hfscr |= 1UL << f->hfscr_bit_nr;
196 			mtspr(SPRN_HFSCR, hfscr);
197 		}
198 	}
199 
200 	if (f->os_support != OS_SUPPORT_NONE) {
201 		if (f->fscr_bit_nr != -1) {
202 			u64 fscr = mfspr(SPRN_FSCR);
203 			fscr |= 1UL << f->fscr_bit_nr;
204 			mtspr(SPRN_FSCR, fscr);
205 		}
206 	}
207 
208 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
209 		uint32_t word = f->hwcap_bit_nr / 32;
210 		uint32_t bit = f->hwcap_bit_nr % 32;
211 
212 		if (word == 0)
213 			cur_cpu_spec->cpu_user_features |= 1U << bit;
214 		else if (word == 1)
215 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
216 		else
217 			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
218 	}
219 
220 	return 1;
221 }
222 
223 static int __init feat_disable(struct dt_cpu_feature *f)
224 {
225 	return 0;
226 }
227 
228 static int __init feat_enable_hv(struct dt_cpu_feature *f)
229 {
230 	u64 lpcr;
231 
232 	if (!hv_mode) {
233 		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
234 		return 0;
235 	}
236 
237 	mtspr(SPRN_LPID, 0);
238 
239 	lpcr = mfspr(SPRN_LPCR);
240 	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
241 	mtspr(SPRN_LPCR, lpcr);
242 
243 	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
244 
245 	return 1;
246 }
247 
248 static int __init feat_enable_le(struct dt_cpu_feature *f)
249 {
250 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
251 	return 1;
252 }
253 
254 static int __init feat_enable_smt(struct dt_cpu_feature *f)
255 {
256 	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
257 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
258 	return 1;
259 }
260 
261 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
262 {
263 	u64 lpcr;
264 
265 	/* Set PECE wakeup modes for ISA 207 */
266 	lpcr = mfspr(SPRN_LPCR);
267 	lpcr |=  LPCR_PECE0;
268 	lpcr |=  LPCR_PECE1;
269 	lpcr |=  LPCR_PECE2;
270 	mtspr(SPRN_LPCR, lpcr);
271 
272 	return 1;
273 }
274 
275 static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
276 {
277 	cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
278 
279 	return 1;
280 }
281 
282 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
283 {
284 	u64 lpcr;
285 
286 	/* Set PECE wakeup modes for ISAv3.0B */
287 	lpcr = mfspr(SPRN_LPCR);
288 	lpcr |=  LPCR_PECE0;
289 	lpcr |=  LPCR_PECE1;
290 	lpcr |=  LPCR_PECE2;
291 	mtspr(SPRN_LPCR, lpcr);
292 
293 	return 1;
294 }
295 
296 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
297 {
298 	u64 lpcr;
299 
300 	lpcr = mfspr(SPRN_LPCR);
301 	lpcr &= ~LPCR_ISL;
302 
303 	/* VRMASD */
304 	lpcr |= LPCR_VPM0;
305 	lpcr &= ~LPCR_VPM1;
306 	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
307 	mtspr(SPRN_LPCR, lpcr);
308 
309 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
310 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
311 
312 	return 1;
313 }
314 
315 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
316 {
317 	u64 lpcr;
318 
319 	system_registers.lpcr_clear |= (LPCR_ISL | LPCR_UPRT | LPCR_HR);
320 	lpcr = mfspr(SPRN_LPCR);
321 	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
322 	mtspr(SPRN_LPCR, lpcr);
323 
324 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
325 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
326 
327 	return 1;
328 }
329 
330 
331 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
332 {
333 #ifdef CONFIG_PPC_RADIX_MMU
334 	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
335 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
336 	cur_cpu_spec->mmu_features |= MMU_FTR_GTSE;
337 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
338 
339 	return 1;
340 #endif
341 	return 0;
342 }
343 
344 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
345 {
346 	u64 lpcr;
347 
348 	/*
349 	 * Linux relies on FSCR[DSCR] being clear, so that we can take the
350 	 * facility unavailable interrupt and track the task's usage of DSCR.
351 	 * See facility_unavailable_exception().
352 	 * Clear the bit here so that feat_enable() doesn't set it.
353 	 */
354 	f->fscr_bit_nr = -1;
355 
356 	feat_enable(f);
357 
358 	lpcr = mfspr(SPRN_LPCR);
359 	lpcr &= ~LPCR_DPFD;
360 	lpcr |=  (4UL << LPCR_DPFD_SH);
361 	mtspr(SPRN_LPCR, lpcr);
362 
363 	return 1;
364 }
365 
366 static void hfscr_pmu_enable(void)
367 {
368 	u64 hfscr = mfspr(SPRN_HFSCR);
369 	hfscr |= PPC_BIT(60);
370 	mtspr(SPRN_HFSCR, hfscr);
371 }
372 
373 static void init_pmu_power8(void)
374 {
375 	if (hv_mode) {
376 		mtspr(SPRN_MMCRC, 0);
377 		mtspr(SPRN_MMCRH, 0);
378 	}
379 
380 	mtspr(SPRN_MMCRA, 0);
381 	mtspr(SPRN_MMCR0, 0);
382 	mtspr(SPRN_MMCR1, 0);
383 	mtspr(SPRN_MMCR2, 0);
384 	mtspr(SPRN_MMCRS, 0);
385 }
386 
387 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
388 {
389 	cur_cpu_spec->platform = "power8";
390 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
391 
392 	return 1;
393 }
394 
395 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
396 {
397 	hfscr_pmu_enable();
398 
399 	init_pmu_power8();
400 	init_pmu_registers = init_pmu_power8;
401 
402 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
403 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
404 	if (pvr_version_is(PVR_POWER8E))
405 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
406 
407 	cur_cpu_spec->num_pmcs		= 6;
408 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
409 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
410 
411 	return 1;
412 }
413 
414 static void init_pmu_power9(void)
415 {
416 	if (hv_mode)
417 		mtspr(SPRN_MMCRC, 0);
418 
419 	mtspr(SPRN_MMCRA, 0);
420 	mtspr(SPRN_MMCR0, 0);
421 	mtspr(SPRN_MMCR1, 0);
422 	mtspr(SPRN_MMCR2, 0);
423 }
424 
425 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
426 {
427 	cur_cpu_spec->platform = "power9";
428 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
429 
430 	return 1;
431 }
432 
433 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
434 {
435 	hfscr_pmu_enable();
436 
437 	init_pmu_power9();
438 	init_pmu_registers = init_pmu_power9;
439 
440 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
441 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
442 
443 	cur_cpu_spec->num_pmcs		= 6;
444 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
445 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
446 
447 	return 1;
448 }
449 
450 static void init_pmu_power10(void)
451 {
452 	init_pmu_power9();
453 
454 	mtspr(SPRN_MMCR3, 0);
455 	mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
456 }
457 
458 static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
459 {
460 	hfscr_pmu_enable();
461 
462 	init_pmu_power10();
463 	init_pmu_registers = init_pmu_power10;
464 
465 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
466 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
467 
468 	cur_cpu_spec->num_pmcs          = 6;
469 	cur_cpu_spec->pmc_type          = PPC_PMC_IBM;
470 	cur_cpu_spec->oprofile_cpu_type = "ppc64/power10";
471 
472 	return 1;
473 }
474 
475 static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
476 {
477 	cur_cpu_spec->platform = "power10";
478 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
479 
480 	return 1;
481 }
482 
483 static int __init feat_enable_tm(struct dt_cpu_feature *f)
484 {
485 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
486 	feat_enable(f);
487 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
488 	return 1;
489 #endif
490 	return 0;
491 }
492 
493 static int __init feat_enable_fp(struct dt_cpu_feature *f)
494 {
495 	feat_enable(f);
496 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
497 
498 	return 1;
499 }
500 
501 static int __init feat_enable_vector(struct dt_cpu_feature *f)
502 {
503 #ifdef CONFIG_ALTIVEC
504 	feat_enable(f);
505 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
506 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
507 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
508 
509 	return 1;
510 #endif
511 	return 0;
512 }
513 
514 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
515 {
516 #ifdef CONFIG_VSX
517 	feat_enable(f);
518 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
519 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
520 
521 	return 1;
522 #endif
523 	return 0;
524 }
525 
526 static int __init feat_enable_purr(struct dt_cpu_feature *f)
527 {
528 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
529 
530 	return 1;
531 }
532 
533 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
534 {
535 	/*
536 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
537 	 * historically been related to the PMU facility. This may have
538 	 * to be decoupled if EBB becomes more generic. For now, follow
539 	 * existing convention.
540 	 */
541 	f->hwcap_bit_nr = -1;
542 	feat_enable(f);
543 
544 	return 1;
545 }
546 
547 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
548 {
549 	u64 lpcr;
550 
551 	/* P9 has an HFSCR for privileged state */
552 	feat_enable(f);
553 
554 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
555 
556 	lpcr = mfspr(SPRN_LPCR);
557 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
558 	mtspr(SPRN_LPCR, lpcr);
559 
560 	return 1;
561 }
562 
563 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
564 {
565 	u64 lpcr;
566 
567 	/*
568 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
569 	 * are always delivered as hypervisor virtualization interrupts (HVI)
570 	 * rather than EE.
571 	 *
572 	 * However LPES0 is not set here, in the chance that an EE does get
573 	 * delivered to the host somehow, the EE handler would not expect it
574 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
575 	 * happen if there is a bug in interrupt controller code, or IC is
576 	 * misconfigured in systemsim.
577 	 */
578 
579 	lpcr = mfspr(SPRN_LPCR);
580 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
581 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
582 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
583 	mtspr(SPRN_LPCR, lpcr);
584 
585 	return 1;
586 }
587 
588 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
589 {
590 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
591 
592 	return 1;
593 }
594 
595 static int __init feat_enable_mma(struct dt_cpu_feature *f)
596 {
597 	u64 pcr;
598 
599 	feat_enable(f);
600 	pcr = mfspr(SPRN_PCR);
601 	pcr &= ~PCR_MMA_DIS;
602 	mtspr(SPRN_PCR, pcr);
603 
604 	return 1;
605 }
606 
607 struct dt_cpu_feature_match {
608 	const char *name;
609 	int (*enable)(struct dt_cpu_feature *f);
610 	u64 cpu_ftr_bit_mask;
611 };
612 
613 static struct dt_cpu_feature_match __initdata
614 		dt_cpu_feature_match_table[] = {
615 	{"hypervisor", feat_enable_hv, 0},
616 	{"big-endian", feat_enable, 0},
617 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
618 	{"smt", feat_enable_smt, 0},
619 	{"interrupt-facilities", feat_enable, 0},
620 	{"system-call-vectored", feat_enable, 0},
621 	{"timer-facilities", feat_enable, 0},
622 	{"timer-facilities-v3", feat_enable, 0},
623 	{"debug-facilities", feat_enable, 0},
624 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
625 	{"branch-tracing", feat_enable, 0},
626 	{"floating-point", feat_enable_fp, 0},
627 	{"vector", feat_enable_vector, 0},
628 	{"vector-scalar", feat_enable_vsx, 0},
629 	{"vector-scalar-v3", feat_enable, 0},
630 	{"decimal-floating-point", feat_enable, 0},
631 	{"decimal-integer", feat_enable, 0},
632 	{"quadword-load-store", feat_enable, 0},
633 	{"vector-crypto", feat_enable, 0},
634 	{"mmu-hash", feat_enable_mmu_hash, 0},
635 	{"mmu-radix", feat_enable_mmu_radix, 0},
636 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
637 	{"virtual-page-class-key-protection", feat_enable, 0},
638 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
639 	{"transactional-memory-v3", feat_enable_tm, 0},
640 	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
641 	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
642 	{"idle-nap", feat_enable_idle_nap, 0},
643 	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
644 	{"idle-stop", feat_enable_idle_stop, 0},
645 	{"machine-check-power8", feat_enable_mce_power8, 0},
646 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
647 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
648 	{"event-based-branch", feat_enable_ebb, 0},
649 	{"target-address-register", feat_enable, 0},
650 	{"branch-history-rolling-buffer", feat_enable, 0},
651 	{"control-register", feat_enable, CPU_FTR_CTRL},
652 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
653 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
654 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
655 	{"no-execute", feat_enable, 0},
656 	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
657 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
658 	{"coprocessor-icswx", feat_enable, 0},
659 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
660 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
661 	{"wait", feat_enable, 0},
662 	{"atomic-memory-operations", feat_enable, 0},
663 	{"branch-v3", feat_enable, 0},
664 	{"copy-paste", feat_enable, 0},
665 	{"decimal-floating-point-v3", feat_enable, 0},
666 	{"decimal-integer-v3", feat_enable, 0},
667 	{"fixed-point-v3", feat_enable, 0},
668 	{"floating-point-v3", feat_enable, 0},
669 	{"group-start-register", feat_enable, 0},
670 	{"pc-relative-addressing", feat_enable, 0},
671 	{"machine-check-power9", feat_enable_mce_power9, 0},
672 	{"machine-check-power10", feat_enable_mce_power10, 0},
673 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
674 	{"performance-monitor-power10", feat_enable_pmu_power10, 0},
675 	{"event-based-branch-v3", feat_enable, 0},
676 	{"random-number-generator", feat_enable, 0},
677 	{"system-call-vectored", feat_disable, 0},
678 	{"trace-interrupt-v3", feat_enable, 0},
679 	{"vector-v3", feat_enable, 0},
680 	{"vector-binary128", feat_enable, 0},
681 	{"vector-binary16", feat_enable, 0},
682 	{"wait-v3", feat_enable, 0},
683 	{"prefix-instructions", feat_enable, 0},
684 	{"matrix-multiply-assist", feat_enable_mma, 0},
685 	{"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
686 };
687 
688 static bool __initdata using_dt_cpu_ftrs;
689 static bool __initdata enable_unknown = true;
690 
691 static int __init dt_cpu_ftrs_parse(char *str)
692 {
693 	if (!str)
694 		return 0;
695 
696 	if (!strcmp(str, "off"))
697 		using_dt_cpu_ftrs = false;
698 	else if (!strcmp(str, "known"))
699 		enable_unknown = false;
700 	else
701 		return 1;
702 
703 	return 0;
704 }
705 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
706 
707 static void __init cpufeatures_setup_start(u32 isa)
708 {
709 	pr_info("setup for ISA %d\n", isa);
710 
711 	if (isa >= ISA_V3_0B) {
712 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
713 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
714 	}
715 
716 	if (isa >= ISA_V3_1) {
717 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
718 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
719 	}
720 }
721 
722 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
723 {
724 	const struct dt_cpu_feature_match *m;
725 	bool known = false;
726 	int i;
727 
728 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
729 		m = &dt_cpu_feature_match_table[i];
730 		if (!strcmp(f->name, m->name)) {
731 			known = true;
732 			if (m->enable(f)) {
733 				cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
734 				break;
735 			}
736 
737 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
738 				f->name);
739 			return false;
740 		}
741 	}
742 
743 	if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
744 		pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
745 			f->name);
746 		return false;
747 	}
748 
749 	if (known)
750 		pr_debug("enabling: %s\n", f->name);
751 	else
752 		pr_debug("enabling: %s (unknown)\n", f->name);
753 
754 	return true;
755 }
756 
757 /*
758  * Handle POWER9 broadcast tlbie invalidation issue using
759  * cpu feature flag.
760  */
761 static __init void update_tlbie_feature_flag(unsigned long pvr)
762 {
763 	if (PVR_VER(pvr) == PVR_POWER9) {
764 		/*
765 		 * Set the tlbie feature flag for anything below
766 		 * Nimbus DD 2.3 and Cumulus DD 1.3
767 		 */
768 		if ((pvr & 0xe000) == 0) {
769 			/* Nimbus */
770 			if ((pvr & 0xfff) < 0x203)
771 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
772 		} else if ((pvr & 0xc000) == 0) {
773 			/* Cumulus */
774 			if ((pvr & 0xfff) < 0x103)
775 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
776 		} else {
777 			WARN_ONCE(1, "Unknown PVR");
778 			cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
779 		}
780 
781 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
782 	}
783 }
784 
785 static __init void cpufeatures_cpu_quirks(void)
786 {
787 	unsigned long version = mfspr(SPRN_PVR);
788 
789 	/*
790 	 * Not all quirks can be derived from the cpufeatures device tree.
791 	 */
792 	if ((version & 0xffffefff) == 0x004e0200) {
793 		/* DD2.0 has no feature flag */
794 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
795 	} else if ((version & 0xffffefff) == 0x004e0201) {
796 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
797 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
798 	} else if ((version & 0xffffefff) == 0x004e0202) {
799 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
800 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
801 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
802 	} else if ((version & 0xffff0000) == 0x004e0000) {
803 		/* DD2.1 and up have DD2_1 */
804 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
805 	}
806 
807 	if ((version & 0xffff0000) == 0x004e0000) {
808 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
809 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
810 	}
811 
812 	update_tlbie_feature_flag(version);
813 }
814 
815 static void __init cpufeatures_setup_finished(void)
816 {
817 	cpufeatures_cpu_quirks();
818 
819 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
820 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
821 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
822 	}
823 
824 	/* Make sure powerpc_base_platform is non-NULL */
825 	powerpc_base_platform = cur_cpu_spec->platform;
826 
827 	system_registers.lpcr = mfspr(SPRN_LPCR);
828 	system_registers.hfscr = mfspr(SPRN_HFSCR);
829 	system_registers.fscr = mfspr(SPRN_FSCR);
830 	system_registers.pcr = mfspr(SPRN_PCR);
831 
832 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
833 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
834 }
835 
836 static int __init disabled_on_cmdline(void)
837 {
838 	unsigned long root, chosen;
839 	const char *p;
840 
841 	root = of_get_flat_dt_root();
842 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
843 	if (chosen == -FDT_ERR_NOTFOUND)
844 		return false;
845 
846 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
847 	if (!p)
848 		return false;
849 
850 	if (strstr(p, "dt_cpu_ftrs=off"))
851 		return true;
852 
853 	return false;
854 }
855 
856 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
857 					int depth, void *data)
858 {
859 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
860 	    && of_get_flat_dt_prop(node, "isa", NULL))
861 		return 1;
862 
863 	return 0;
864 }
865 
866 bool __init dt_cpu_ftrs_in_use(void)
867 {
868 	return using_dt_cpu_ftrs;
869 }
870 
871 bool __init dt_cpu_ftrs_init(void *fdt)
872 {
873 	using_dt_cpu_ftrs = false;
874 
875 	/* Setup and verify the FDT, if it fails we just bail */
876 	if (!early_init_dt_verify(fdt))
877 		return false;
878 
879 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
880 		return false;
881 
882 	if (disabled_on_cmdline())
883 		return false;
884 
885 	cpufeatures_setup_cpu();
886 
887 	using_dt_cpu_ftrs = true;
888 	return true;
889 }
890 
891 static int nr_dt_cpu_features;
892 static struct dt_cpu_feature *dt_cpu_features;
893 
894 static int __init process_cpufeatures_node(unsigned long node,
895 					  const char *uname, int i)
896 {
897 	const __be32 *prop;
898 	struct dt_cpu_feature *f;
899 	int len;
900 
901 	f = &dt_cpu_features[i];
902 
903 	f->node = node;
904 
905 	f->name = uname;
906 
907 	prop = of_get_flat_dt_prop(node, "isa", &len);
908 	if (!prop) {
909 		pr_warn("%s: missing isa property\n", uname);
910 		return 0;
911 	}
912 	f->isa = be32_to_cpup(prop);
913 
914 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
915 	if (!prop) {
916 		pr_warn("%s: missing usable-privilege property", uname);
917 		return 0;
918 	}
919 	f->usable_privilege = be32_to_cpup(prop);
920 
921 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
922 	if (prop)
923 		f->hv_support = be32_to_cpup(prop);
924 	else
925 		f->hv_support = HV_SUPPORT_NONE;
926 
927 	prop = of_get_flat_dt_prop(node, "os-support", &len);
928 	if (prop)
929 		f->os_support = be32_to_cpup(prop);
930 	else
931 		f->os_support = OS_SUPPORT_NONE;
932 
933 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
934 	if (prop)
935 		f->hfscr_bit_nr = be32_to_cpup(prop);
936 	else
937 		f->hfscr_bit_nr = -1;
938 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
939 	if (prop)
940 		f->fscr_bit_nr = be32_to_cpup(prop);
941 	else
942 		f->fscr_bit_nr = -1;
943 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
944 	if (prop)
945 		f->hwcap_bit_nr = be32_to_cpup(prop);
946 	else
947 		f->hwcap_bit_nr = -1;
948 
949 	if (f->usable_privilege & USABLE_HV) {
950 		if (!(mfmsr() & MSR_HV)) {
951 			pr_warn("%s: HV feature passed to guest\n", uname);
952 			return 0;
953 		}
954 
955 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
956 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
957 			return 0;
958 		}
959 
960 		if (f->hv_support == HV_SUPPORT_HFSCR) {
961 			if (f->hfscr_bit_nr == -1) {
962 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
963 				return 0;
964 			}
965 		}
966 	} else {
967 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
968 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
969 			return 0;
970 		}
971 	}
972 
973 	if (f->usable_privilege & USABLE_OS) {
974 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
975 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
976 			return 0;
977 		}
978 
979 		if (f->os_support == OS_SUPPORT_FSCR) {
980 			if (f->fscr_bit_nr == -1) {
981 				pr_warn("%s: missing fscr_bit_nr\n", uname);
982 				return 0;
983 			}
984 		}
985 	} else {
986 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
987 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
988 			return 0;
989 		}
990 	}
991 
992 	if (!(f->usable_privilege & USABLE_PR)) {
993 		if (f->hwcap_bit_nr != -1) {
994 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
995 			return 0;
996 		}
997 	}
998 
999 	/* Do all the independent features in the first pass */
1000 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
1001 		if (cpufeatures_process_feature(f))
1002 			f->enabled = 1;
1003 		else
1004 			f->disabled = 1;
1005 	}
1006 
1007 	return 0;
1008 }
1009 
1010 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
1011 {
1012 	const __be32 *prop;
1013 	int len;
1014 	int nr_deps;
1015 	int i;
1016 
1017 	if (f->enabled || f->disabled)
1018 		return;
1019 
1020 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
1021 	if (!prop) {
1022 		pr_warn("%s: missing dependencies property", f->name);
1023 		return;
1024 	}
1025 
1026 	nr_deps = len / sizeof(int);
1027 
1028 	for (i = 0; i < nr_deps; i++) {
1029 		unsigned long phandle = be32_to_cpu(prop[i]);
1030 		int j;
1031 
1032 		for (j = 0; j < nr_dt_cpu_features; j++) {
1033 			struct dt_cpu_feature *d = &dt_cpu_features[j];
1034 
1035 			if (of_get_flat_dt_phandle(d->node) == phandle) {
1036 				cpufeatures_deps_enable(d);
1037 				if (d->disabled) {
1038 					f->disabled = 1;
1039 					return;
1040 				}
1041 			}
1042 		}
1043 	}
1044 
1045 	if (cpufeatures_process_feature(f))
1046 		f->enabled = 1;
1047 	else
1048 		f->disabled = 1;
1049 }
1050 
1051 static int __init scan_cpufeatures_subnodes(unsigned long node,
1052 					  const char *uname,
1053 					  void *data)
1054 {
1055 	int *count = data;
1056 
1057 	process_cpufeatures_node(node, uname, *count);
1058 
1059 	(*count)++;
1060 
1061 	return 0;
1062 }
1063 
1064 static int __init count_cpufeatures_subnodes(unsigned long node,
1065 					  const char *uname,
1066 					  void *data)
1067 {
1068 	int *count = data;
1069 
1070 	(*count)++;
1071 
1072 	return 0;
1073 }
1074 
1075 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1076 					    *uname, int depth, void *data)
1077 {
1078 	const __be32 *prop;
1079 	int count, i;
1080 	u32 isa;
1081 
1082 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1083 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1084 		return 0;
1085 
1086 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1087 	if (!prop)
1088 		/* We checked before, "can't happen" */
1089 		return 0;
1090 
1091 	isa = be32_to_cpup(prop);
1092 
1093 	/* Count and allocate space for cpu features */
1094 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1095 						&nr_dt_cpu_features);
1096 	dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1097 	if (!dt_cpu_features)
1098 		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1099 		      __func__,
1100 		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1101 		      PAGE_SIZE);
1102 
1103 	cpufeatures_setup_start(isa);
1104 
1105 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1106 	count = 0;
1107 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1108 
1109 	/* Recursive enable remaining features with dependencies */
1110 	for (i = 0; i < nr_dt_cpu_features; i++) {
1111 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1112 
1113 		cpufeatures_deps_enable(f);
1114 	}
1115 
1116 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1117 	if (prop && strlen((char *)prop) != 0) {
1118 		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1119 		cur_cpu_spec->cpu_name = dt_cpu_name;
1120 	}
1121 
1122 	cpufeatures_setup_finished();
1123 
1124 	memblock_free(__pa(dt_cpu_features),
1125 			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1126 
1127 	return 0;
1128 }
1129 
1130 void __init dt_cpu_ftrs_scan(void)
1131 {
1132 	if (!using_dt_cpu_ftrs)
1133 		return;
1134 
1135 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1136 }
1137