1 /*
2  * Copyright 2017, Nicholas Piggin, IBM Corporation
3  * Licensed under GPLv2.
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 
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 CPU_FTRS_BASE \
57 	   (CPU_FTR_USE_TB | \
58 	    CPU_FTR_LWSYNC | \
59 	    CPU_FTR_FPU_UNAVAILABLE |\
60 	    CPU_FTR_NODSISRALIGN |\
61 	    CPU_FTR_NOEXECUTE |\
62 	    CPU_FTR_COHERENT_ICACHE | \
63 	    CPU_FTR_STCX_CHECKS_ADDRESS |\
64 	    CPU_FTR_POPCNTB | CPU_FTR_POPCNTD | \
65 	    CPU_FTR_DAWR | \
66 	    CPU_FTR_ARCH_206 |\
67 	    CPU_FTR_ARCH_207S)
68 
69 #define MMU_FTRS_HASH_BASE (MMU_FTRS_POWER8)
70 
71 #define COMMON_USER_BASE	(PPC_FEATURE_32 | PPC_FEATURE_64 | \
72 				 PPC_FEATURE_ARCH_2_06 |\
73 				 PPC_FEATURE_ICACHE_SNOOP)
74 #define COMMON_USER2_BASE	(PPC_FEATURE2_ARCH_2_07 | \
75 				 PPC_FEATURE2_ISEL)
76 /*
77  * Set up the base CPU
78  */
79 
80 extern void __flush_tlb_power8(unsigned int action);
81 extern void __flush_tlb_power9(unsigned int action);
82 extern long __machine_check_early_realmode_p8(struct pt_regs *regs);
83 extern long __machine_check_early_realmode_p9(struct pt_regs *regs);
84 
85 static int hv_mode;
86 
87 static struct {
88 	u64	lpcr;
89 	u64	hfscr;
90 	u64	fscr;
91 } system_registers;
92 
93 static void (*init_pmu_registers)(void);
94 
95 static void cpufeatures_flush_tlb(void)
96 {
97 	unsigned long rb;
98 	unsigned int i, num_sets;
99 
100 	/*
101 	 * This is a temporary measure to keep equivalent TLB flush as the
102 	 * cputable based setup code.
103 	 */
104 	switch (PVR_VER(mfspr(SPRN_PVR))) {
105 	case PVR_POWER8:
106 	case PVR_POWER8E:
107 	case PVR_POWER8NVL:
108 		num_sets = POWER8_TLB_SETS;
109 		break;
110 	case PVR_POWER9:
111 		num_sets = POWER9_TLB_SETS_HASH;
112 		break;
113 	default:
114 		num_sets = 1;
115 		pr_err("unknown CPU version for boot TLB flush\n");
116 		break;
117 	}
118 
119 	asm volatile("ptesync" : : : "memory");
120 	rb = TLBIEL_INVAL_SET;
121 	for (i = 0; i < num_sets; i++) {
122 		asm volatile("tlbiel %0" : : "r" (rb));
123 		rb += 1 << TLBIEL_INVAL_SET_SHIFT;
124 	}
125 	asm volatile("ptesync" : : : "memory");
126 }
127 
128 static void __restore_cpu_cpufeatures(void)
129 {
130 	/*
131 	 * LPCR is restored by the power on engine already. It can be changed
132 	 * after early init e.g., by radix enable, and we have no unified API
133 	 * for saving and restoring such SPRs.
134 	 *
135 	 * This ->restore hook should really be removed from idle and register
136 	 * restore moved directly into the idle restore code, because this code
137 	 * doesn't know how idle is implemented or what it needs restored here.
138 	 *
139 	 * The best we can do to accommodate secondary boot and idle restore
140 	 * for now is "or" LPCR with existing.
141 	 */
142 
143 	mtspr(SPRN_LPCR, system_registers.lpcr | mfspr(SPRN_LPCR));
144 	if (hv_mode) {
145 		mtspr(SPRN_LPID, 0);
146 		mtspr(SPRN_HFSCR, system_registers.hfscr);
147 	}
148 	mtspr(SPRN_FSCR, system_registers.fscr);
149 
150 	if (init_pmu_registers)
151 		init_pmu_registers();
152 
153 	cpufeatures_flush_tlb();
154 }
155 
156 static char dt_cpu_name[64];
157 
158 static struct cpu_spec __initdata base_cpu_spec = {
159 	.cpu_name		= NULL,
160 	.cpu_features		= CPU_FTRS_BASE,
161 	.cpu_user_features	= COMMON_USER_BASE,
162 	.cpu_user_features2	= COMMON_USER2_BASE,
163 	.mmu_features		= 0,
164 	.icache_bsize		= 32, /* minimum block size, fixed by */
165 	.dcache_bsize		= 32, /* cache info init.             */
166 	.num_pmcs		= 0,
167 	.pmc_type		= PPC_PMC_DEFAULT,
168 	.oprofile_cpu_type	= NULL,
169 	.oprofile_type		= PPC_OPROFILE_INVALID,
170 	.cpu_setup		= NULL,
171 	.cpu_restore		= __restore_cpu_cpufeatures,
172 	.flush_tlb		= NULL,
173 	.machine_check_early	= NULL,
174 	.platform		= NULL,
175 };
176 
177 static void __init cpufeatures_setup_cpu(void)
178 {
179 	set_cur_cpu_spec(&base_cpu_spec);
180 
181 	cur_cpu_spec->pvr_mask = -1;
182 	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
183 
184 	/* Initialize the base environment -- clear FSCR/HFSCR.  */
185 	hv_mode = !!(mfmsr() & MSR_HV);
186 	if (hv_mode) {
187 		/* CPU_FTR_HVMODE is used early in PACA setup */
188 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
189 		mtspr(SPRN_HFSCR, 0);
190 	}
191 	mtspr(SPRN_FSCR, 0);
192 
193 	/*
194 	 * LPCR does not get cleared, to match behaviour with secondaries
195 	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
196 	 * could clear LPCR too.
197 	 */
198 }
199 
200 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
201 {
202 	if (f->hv_support == HV_SUPPORT_NONE) {
203 	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
204 		u64 hfscr = mfspr(SPRN_HFSCR);
205 		hfscr |= 1UL << f->hfscr_bit_nr;
206 		mtspr(SPRN_HFSCR, hfscr);
207 	} else {
208 		/* Does not have a known recipe */
209 		return 0;
210 	}
211 
212 	if (f->os_support == OS_SUPPORT_NONE) {
213 	} else if (f->os_support & OS_SUPPORT_FSCR) {
214 		u64 fscr = mfspr(SPRN_FSCR);
215 		fscr |= 1UL << f->fscr_bit_nr;
216 		mtspr(SPRN_FSCR, fscr);
217 	} else {
218 		/* Does not have a known recipe */
219 		return 0;
220 	}
221 
222 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
223 		uint32_t word = f->hwcap_bit_nr / 32;
224 		uint32_t bit = f->hwcap_bit_nr % 32;
225 
226 		if (word == 0)
227 			cur_cpu_spec->cpu_user_features |= 1U << bit;
228 		else if (word == 1)
229 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
230 		else
231 			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
232 	}
233 
234 	return 1;
235 }
236 
237 static int __init feat_enable(struct dt_cpu_feature *f)
238 {
239 	if (f->hv_support != HV_SUPPORT_NONE) {
240 		if (f->hfscr_bit_nr != -1) {
241 			u64 hfscr = mfspr(SPRN_HFSCR);
242 			hfscr |= 1UL << f->hfscr_bit_nr;
243 			mtspr(SPRN_HFSCR, hfscr);
244 		}
245 	}
246 
247 	if (f->os_support != OS_SUPPORT_NONE) {
248 		if (f->fscr_bit_nr != -1) {
249 			u64 fscr = mfspr(SPRN_FSCR);
250 			fscr |= 1UL << f->fscr_bit_nr;
251 			mtspr(SPRN_FSCR, fscr);
252 		}
253 	}
254 
255 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
256 		uint32_t word = f->hwcap_bit_nr / 32;
257 		uint32_t bit = f->hwcap_bit_nr % 32;
258 
259 		if (word == 0)
260 			cur_cpu_spec->cpu_user_features |= 1U << bit;
261 		else if (word == 1)
262 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
263 		else
264 			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
265 	}
266 
267 	return 1;
268 }
269 
270 static int __init feat_disable(struct dt_cpu_feature *f)
271 {
272 	return 0;
273 }
274 
275 static int __init feat_enable_hv(struct dt_cpu_feature *f)
276 {
277 	u64 lpcr;
278 
279 	if (!hv_mode) {
280 		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
281 		return 0;
282 	}
283 
284 	mtspr(SPRN_LPID, 0);
285 
286 	lpcr = mfspr(SPRN_LPCR);
287 	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
288 	mtspr(SPRN_LPCR, lpcr);
289 
290 	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
291 
292 	return 1;
293 }
294 
295 static int __init feat_enable_le(struct dt_cpu_feature *f)
296 {
297 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
298 	return 1;
299 }
300 
301 static int __init feat_enable_smt(struct dt_cpu_feature *f)
302 {
303 	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
304 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
305 	return 1;
306 }
307 
308 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
309 {
310 	u64 lpcr;
311 
312 	/* Set PECE wakeup modes for ISA 207 */
313 	lpcr = mfspr(SPRN_LPCR);
314 	lpcr |=  LPCR_PECE0;
315 	lpcr |=  LPCR_PECE1;
316 	lpcr |=  LPCR_PECE2;
317 	mtspr(SPRN_LPCR, lpcr);
318 
319 	return 1;
320 }
321 
322 static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
323 {
324 	cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
325 
326 	return 1;
327 }
328 
329 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
330 {
331 	u64 lpcr;
332 
333 	/* Set PECE wakeup modes for ISAv3.0B */
334 	lpcr = mfspr(SPRN_LPCR);
335 	lpcr |=  LPCR_PECE0;
336 	lpcr |=  LPCR_PECE1;
337 	lpcr |=  LPCR_PECE2;
338 	mtspr(SPRN_LPCR, lpcr);
339 
340 	return 1;
341 }
342 
343 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
344 {
345 	u64 lpcr;
346 
347 	lpcr = mfspr(SPRN_LPCR);
348 	lpcr &= ~LPCR_ISL;
349 
350 	/* VRMASD */
351 	lpcr |= LPCR_VPM0;
352 	lpcr &= ~LPCR_VPM1;
353 	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
354 	mtspr(SPRN_LPCR, lpcr);
355 
356 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
357 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
358 
359 	return 1;
360 }
361 
362 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
363 {
364 	u64 lpcr;
365 
366 	lpcr = mfspr(SPRN_LPCR);
367 	lpcr &= ~LPCR_ISL;
368 	mtspr(SPRN_LPCR, lpcr);
369 
370 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
371 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
372 
373 	return 1;
374 }
375 
376 
377 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
378 {
379 #ifdef CONFIG_PPC_RADIX_MMU
380 	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
381 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
382 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
383 
384 	return 1;
385 #endif
386 	return 0;
387 }
388 
389 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
390 {
391 	u64 lpcr;
392 
393 	feat_enable(f);
394 
395 	lpcr = mfspr(SPRN_LPCR);
396 	lpcr &= ~LPCR_DPFD;
397 	lpcr |=  (4UL << LPCR_DPFD_SH);
398 	mtspr(SPRN_LPCR, lpcr);
399 
400 	return 1;
401 }
402 
403 static void hfscr_pmu_enable(void)
404 {
405 	u64 hfscr = mfspr(SPRN_HFSCR);
406 	hfscr |= PPC_BIT(60);
407 	mtspr(SPRN_HFSCR, hfscr);
408 }
409 
410 static void init_pmu_power8(void)
411 {
412 	if (hv_mode) {
413 		mtspr(SPRN_MMCRC, 0);
414 		mtspr(SPRN_MMCRH, 0);
415 	}
416 
417 	mtspr(SPRN_MMCRA, 0);
418 	mtspr(SPRN_MMCR0, 0);
419 	mtspr(SPRN_MMCR1, 0);
420 	mtspr(SPRN_MMCR2, 0);
421 	mtspr(SPRN_MMCRS, 0);
422 }
423 
424 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
425 {
426 	cur_cpu_spec->platform = "power8";
427 	cur_cpu_spec->flush_tlb = __flush_tlb_power8;
428 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
429 
430 	return 1;
431 }
432 
433 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
434 {
435 	hfscr_pmu_enable();
436 
437 	init_pmu_power8();
438 	init_pmu_registers = init_pmu_power8;
439 
440 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
441 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
442 	if (pvr_version_is(PVR_POWER8E))
443 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
444 
445 	cur_cpu_spec->num_pmcs		= 6;
446 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
447 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
448 
449 	return 1;
450 }
451 
452 static void init_pmu_power9(void)
453 {
454 	if (hv_mode)
455 		mtspr(SPRN_MMCRC, 0);
456 
457 	mtspr(SPRN_MMCRA, 0);
458 	mtspr(SPRN_MMCR0, 0);
459 	mtspr(SPRN_MMCR1, 0);
460 	mtspr(SPRN_MMCR2, 0);
461 }
462 
463 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
464 {
465 	cur_cpu_spec->platform = "power9";
466 	cur_cpu_spec->flush_tlb = __flush_tlb_power9;
467 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
468 
469 	return 1;
470 }
471 
472 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
473 {
474 	hfscr_pmu_enable();
475 
476 	init_pmu_power9();
477 	init_pmu_registers = init_pmu_power9;
478 
479 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
480 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
481 
482 	cur_cpu_spec->num_pmcs		= 6;
483 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
484 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
485 
486 	return 1;
487 }
488 
489 static int __init feat_enable_tm(struct dt_cpu_feature *f)
490 {
491 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
492 	feat_enable(f);
493 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
494 	return 1;
495 #endif
496 	return 0;
497 }
498 
499 static int __init feat_enable_fp(struct dt_cpu_feature *f)
500 {
501 	feat_enable(f);
502 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
503 
504 	return 1;
505 }
506 
507 static int __init feat_enable_vector(struct dt_cpu_feature *f)
508 {
509 #ifdef CONFIG_ALTIVEC
510 	feat_enable(f);
511 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
512 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
513 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
514 
515 	return 1;
516 #endif
517 	return 0;
518 }
519 
520 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
521 {
522 #ifdef CONFIG_VSX
523 	feat_enable(f);
524 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
525 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
526 
527 	return 1;
528 #endif
529 	return 0;
530 }
531 
532 static int __init feat_enable_purr(struct dt_cpu_feature *f)
533 {
534 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
535 
536 	return 1;
537 }
538 
539 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
540 {
541 	/*
542 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
543 	 * historically been related to the PMU facility. This may have
544 	 * to be decoupled if EBB becomes more generic. For now, follow
545 	 * existing convention.
546 	 */
547 	f->hwcap_bit_nr = -1;
548 	feat_enable(f);
549 
550 	return 1;
551 }
552 
553 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
554 {
555 	u64 lpcr;
556 
557 	/* P9 has an HFSCR for privileged state */
558 	feat_enable(f);
559 
560 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
561 
562 	lpcr = mfspr(SPRN_LPCR);
563 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
564 	mtspr(SPRN_LPCR, lpcr);
565 
566 	return 1;
567 }
568 
569 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
570 {
571 	u64 lpcr;
572 
573 	/*
574 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
575 	 * are always delivered as hypervisor virtualization interrupts (HVI)
576 	 * rather than EE.
577 	 *
578 	 * However LPES0 is not set here, in the chance that an EE does get
579 	 * delivered to the host somehow, the EE handler would not expect it
580 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
581 	 * happen if there is a bug in interrupt controller code, or IC is
582 	 * misconfigured in systemsim.
583 	 */
584 
585 	lpcr = mfspr(SPRN_LPCR);
586 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
587 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
588 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
589 	mtspr(SPRN_LPCR, lpcr);
590 
591 	return 1;
592 }
593 
594 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
595 {
596 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
597 
598 	return 1;
599 }
600 
601 struct dt_cpu_feature_match {
602 	const char *name;
603 	int (*enable)(struct dt_cpu_feature *f);
604 	u64 cpu_ftr_bit_mask;
605 };
606 
607 static struct dt_cpu_feature_match __initdata
608 		dt_cpu_feature_match_table[] = {
609 	{"hypervisor", feat_enable_hv, 0},
610 	{"big-endian", feat_enable, 0},
611 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
612 	{"smt", feat_enable_smt, 0},
613 	{"interrupt-facilities", feat_enable, 0},
614 	{"timer-facilities", feat_enable, 0},
615 	{"timer-facilities-v3", feat_enable, 0},
616 	{"debug-facilities", feat_enable, 0},
617 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
618 	{"branch-tracing", feat_enable, 0},
619 	{"floating-point", feat_enable_fp, 0},
620 	{"vector", feat_enable_vector, 0},
621 	{"vector-scalar", feat_enable_vsx, 0},
622 	{"vector-scalar-v3", feat_enable, 0},
623 	{"decimal-floating-point", feat_enable, 0},
624 	{"decimal-integer", feat_enable, 0},
625 	{"quadword-load-store", feat_enable, 0},
626 	{"vector-crypto", feat_enable, 0},
627 	{"mmu-hash", feat_enable_mmu_hash, 0},
628 	{"mmu-radix", feat_enable_mmu_radix, 0},
629 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
630 	{"virtual-page-class-key-protection", feat_enable, 0},
631 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
632 	{"transactional-memory-v3", feat_enable_tm, 0},
633 	{"idle-nap", feat_enable_idle_nap, 0},
634 	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
635 	{"idle-stop", feat_enable_idle_stop, 0},
636 	{"machine-check-power8", feat_enable_mce_power8, 0},
637 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
638 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
639 	{"event-based-branch", feat_enable_ebb, 0},
640 	{"target-address-register", feat_enable, 0},
641 	{"branch-history-rolling-buffer", feat_enable, 0},
642 	{"control-register", feat_enable, CPU_FTR_CTRL},
643 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
644 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
645 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
646 	{"no-execute", feat_enable, 0},
647 	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
648 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
649 	{"coprocessor-icswx", feat_enable, CPU_FTR_ICSWX},
650 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
651 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
652 	{"wait", feat_enable, 0},
653 	{"atomic-memory-operations", feat_enable, 0},
654 	{"branch-v3", feat_enable, 0},
655 	{"copy-paste", feat_enable, 0},
656 	{"decimal-floating-point-v3", feat_enable, 0},
657 	{"decimal-integer-v3", feat_enable, 0},
658 	{"fixed-point-v3", feat_enable, 0},
659 	{"floating-point-v3", feat_enable, 0},
660 	{"group-start-register", feat_enable, 0},
661 	{"pc-relative-addressing", feat_enable, 0},
662 	{"machine-check-power9", feat_enable_mce_power9, 0},
663 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
664 	{"event-based-branch-v3", feat_enable, 0},
665 	{"random-number-generator", feat_enable, 0},
666 	{"system-call-vectored", feat_disable, 0},
667 	{"trace-interrupt-v3", feat_enable, 0},
668 	{"vector-v3", feat_enable, 0},
669 	{"vector-binary128", feat_enable, 0},
670 	{"vector-binary16", feat_enable, 0},
671 	{"wait-v3", feat_enable, 0},
672 };
673 
674 static bool __initdata using_dt_cpu_ftrs;
675 static bool __initdata enable_unknown = true;
676 
677 static int __init dt_cpu_ftrs_parse(char *str)
678 {
679 	if (!str)
680 		return 0;
681 
682 	if (!strcmp(str, "off"))
683 		using_dt_cpu_ftrs = false;
684 	else if (!strcmp(str, "known"))
685 		enable_unknown = false;
686 	else
687 		return 1;
688 
689 	return 0;
690 }
691 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
692 
693 static void __init cpufeatures_setup_start(u32 isa)
694 {
695 	pr_info("setup for ISA %d\n", isa);
696 
697 	if (isa >= 3000) {
698 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
699 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
700 	}
701 }
702 
703 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
704 {
705 	const struct dt_cpu_feature_match *m;
706 	bool known = false;
707 	int i;
708 
709 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
710 		m = &dt_cpu_feature_match_table[i];
711 		if (!strcmp(f->name, m->name)) {
712 			known = true;
713 			if (m->enable(f))
714 				break;
715 
716 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
717 				f->name);
718 			return false;
719 		}
720 	}
721 
722 	if (!known && enable_unknown) {
723 		if (!feat_try_enable_unknown(f)) {
724 			pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
725 				f->name);
726 			return false;
727 		}
728 	}
729 
730 	if (m->cpu_ftr_bit_mask)
731 		cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
732 
733 	if (known)
734 		pr_debug("enabling: %s\n", f->name);
735 	else
736 		pr_debug("enabling: %s (unknown)\n", f->name);
737 
738 	return true;
739 }
740 
741 static __init void cpufeatures_cpu_quirks(void)
742 {
743 	int version = mfspr(SPRN_PVR);
744 
745 	/*
746 	 * Not all quirks can be derived from the cpufeatures device tree.
747 	 */
748 	if ((version & 0xffffff00) == 0x004e0100)
749 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD1;
750 }
751 
752 static void __init cpufeatures_setup_finished(void)
753 {
754 	cpufeatures_cpu_quirks();
755 
756 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
757 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
758 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
759 	}
760 
761 	system_registers.lpcr = mfspr(SPRN_LPCR);
762 	system_registers.hfscr = mfspr(SPRN_HFSCR);
763 	system_registers.fscr = mfspr(SPRN_FSCR);
764 
765 	cpufeatures_flush_tlb();
766 
767 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
768 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
769 }
770 
771 static int __init disabled_on_cmdline(void)
772 {
773 	unsigned long root, chosen;
774 	const char *p;
775 
776 	root = of_get_flat_dt_root();
777 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
778 	if (chosen == -FDT_ERR_NOTFOUND)
779 		return false;
780 
781 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
782 	if (!p)
783 		return false;
784 
785 	if (strstr(p, "dt_cpu_ftrs=off"))
786 		return true;
787 
788 	return false;
789 }
790 
791 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
792 					int depth, void *data)
793 {
794 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
795 	    && of_get_flat_dt_prop(node, "isa", NULL))
796 		return 1;
797 
798 	return 0;
799 }
800 
801 bool __init dt_cpu_ftrs_in_use(void)
802 {
803 	return using_dt_cpu_ftrs;
804 }
805 
806 bool __init dt_cpu_ftrs_init(void *fdt)
807 {
808 	using_dt_cpu_ftrs = false;
809 
810 	/* Setup and verify the FDT, if it fails we just bail */
811 	if (!early_init_dt_verify(fdt))
812 		return false;
813 
814 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
815 		return false;
816 
817 	if (disabled_on_cmdline())
818 		return false;
819 
820 	cpufeatures_setup_cpu();
821 
822 	using_dt_cpu_ftrs = true;
823 	return true;
824 }
825 
826 static int nr_dt_cpu_features;
827 static struct dt_cpu_feature *dt_cpu_features;
828 
829 static int __init process_cpufeatures_node(unsigned long node,
830 					  const char *uname, int i)
831 {
832 	const __be32 *prop;
833 	struct dt_cpu_feature *f;
834 	int len;
835 
836 	f = &dt_cpu_features[i];
837 	memset(f, 0, sizeof(struct dt_cpu_feature));
838 
839 	f->node = node;
840 
841 	f->name = uname;
842 
843 	prop = of_get_flat_dt_prop(node, "isa", &len);
844 	if (!prop) {
845 		pr_warn("%s: missing isa property\n", uname);
846 		return 0;
847 	}
848 	f->isa = be32_to_cpup(prop);
849 
850 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
851 	if (!prop) {
852 		pr_warn("%s: missing usable-privilege property", uname);
853 		return 0;
854 	}
855 	f->usable_privilege = be32_to_cpup(prop);
856 
857 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
858 	if (prop)
859 		f->hv_support = be32_to_cpup(prop);
860 	else
861 		f->hv_support = HV_SUPPORT_NONE;
862 
863 	prop = of_get_flat_dt_prop(node, "os-support", &len);
864 	if (prop)
865 		f->os_support = be32_to_cpup(prop);
866 	else
867 		f->os_support = OS_SUPPORT_NONE;
868 
869 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
870 	if (prop)
871 		f->hfscr_bit_nr = be32_to_cpup(prop);
872 	else
873 		f->hfscr_bit_nr = -1;
874 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
875 	if (prop)
876 		f->fscr_bit_nr = be32_to_cpup(prop);
877 	else
878 		f->fscr_bit_nr = -1;
879 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
880 	if (prop)
881 		f->hwcap_bit_nr = be32_to_cpup(prop);
882 	else
883 		f->hwcap_bit_nr = -1;
884 
885 	if (f->usable_privilege & USABLE_HV) {
886 		if (!(mfmsr() & MSR_HV)) {
887 			pr_warn("%s: HV feature passed to guest\n", uname);
888 			return 0;
889 		}
890 
891 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
892 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
893 			return 0;
894 		}
895 
896 		if (f->hv_support == HV_SUPPORT_HFSCR) {
897 			if (f->hfscr_bit_nr == -1) {
898 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
899 				return 0;
900 			}
901 		}
902 	} else {
903 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
904 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
905 			return 0;
906 		}
907 	}
908 
909 	if (f->usable_privilege & USABLE_OS) {
910 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
911 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
912 			return 0;
913 		}
914 
915 		if (f->os_support == OS_SUPPORT_FSCR) {
916 			if (f->fscr_bit_nr == -1) {
917 				pr_warn("%s: missing fscr_bit_nr\n", uname);
918 				return 0;
919 			}
920 		}
921 	} else {
922 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
923 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
924 			return 0;
925 		}
926 	}
927 
928 	if (!(f->usable_privilege & USABLE_PR)) {
929 		if (f->hwcap_bit_nr != -1) {
930 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
931 			return 0;
932 		}
933 	}
934 
935 	/* Do all the independent features in the first pass */
936 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
937 		if (cpufeatures_process_feature(f))
938 			f->enabled = 1;
939 		else
940 			f->disabled = 1;
941 	}
942 
943 	return 0;
944 }
945 
946 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
947 {
948 	const __be32 *prop;
949 	int len;
950 	int nr_deps;
951 	int i;
952 
953 	if (f->enabled || f->disabled)
954 		return;
955 
956 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
957 	if (!prop) {
958 		pr_warn("%s: missing dependencies property", f->name);
959 		return;
960 	}
961 
962 	nr_deps = len / sizeof(int);
963 
964 	for (i = 0; i < nr_deps; i++) {
965 		unsigned long phandle = be32_to_cpu(prop[i]);
966 		int j;
967 
968 		for (j = 0; j < nr_dt_cpu_features; j++) {
969 			struct dt_cpu_feature *d = &dt_cpu_features[j];
970 
971 			if (of_get_flat_dt_phandle(d->node) == phandle) {
972 				cpufeatures_deps_enable(d);
973 				if (d->disabled) {
974 					f->disabled = 1;
975 					return;
976 				}
977 			}
978 		}
979 	}
980 
981 	if (cpufeatures_process_feature(f))
982 		f->enabled = 1;
983 	else
984 		f->disabled = 1;
985 }
986 
987 static int __init scan_cpufeatures_subnodes(unsigned long node,
988 					  const char *uname,
989 					  void *data)
990 {
991 	int *count = data;
992 
993 	process_cpufeatures_node(node, uname, *count);
994 
995 	(*count)++;
996 
997 	return 0;
998 }
999 
1000 static int __init count_cpufeatures_subnodes(unsigned long node,
1001 					  const char *uname,
1002 					  void *data)
1003 {
1004 	int *count = data;
1005 
1006 	(*count)++;
1007 
1008 	return 0;
1009 }
1010 
1011 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1012 					    *uname, int depth, void *data)
1013 {
1014 	const __be32 *prop;
1015 	int count, i;
1016 	u32 isa;
1017 
1018 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1019 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1020 		return 0;
1021 
1022 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1023 	if (!prop)
1024 		/* We checked before, "can't happen" */
1025 		return 0;
1026 
1027 	isa = be32_to_cpup(prop);
1028 
1029 	/* Count and allocate space for cpu features */
1030 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1031 						&nr_dt_cpu_features);
1032 	dt_cpu_features = __va(
1033 		memblock_alloc(sizeof(struct dt_cpu_feature)*
1034 				nr_dt_cpu_features, PAGE_SIZE));
1035 
1036 	cpufeatures_setup_start(isa);
1037 
1038 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1039 	count = 0;
1040 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1041 
1042 	/* Recursive enable remaining features with dependencies */
1043 	for (i = 0; i < nr_dt_cpu_features; i++) {
1044 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1045 
1046 		cpufeatures_deps_enable(f);
1047 	}
1048 
1049 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1050 	if (prop && strlen((char *)prop) != 0) {
1051 		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1052 		cur_cpu_spec->cpu_name = dt_cpu_name;
1053 	}
1054 
1055 	cpufeatures_setup_finished();
1056 
1057 	memblock_free(__pa(dt_cpu_features),
1058 			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1059 
1060 	return 0;
1061 }
1062 
1063 void __init dt_cpu_ftrs_scan(void)
1064 {
1065 	if (!using_dt_cpu_ftrs)
1066 		return;
1067 
1068 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1069 }
1070