1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright 2017, Nicholas Piggin, IBM Corporation
4  */
5 
6 #define pr_fmt(fmt) "dt-cpu-ftrs: " fmt
7 
8 #include <linux/export.h>
9 #include <linux/init.h>
10 #include <linux/jump_label.h>
11 #include <linux/libfdt.h>
12 #include <linux/memblock.h>
13 #include <linux/printk.h>
14 #include <linux/sched.h>
15 #include <linux/string.h>
16 #include <linux/threads.h>
17 
18 #include <asm/cputable.h>
19 #include <asm/dt_cpu_ftrs.h>
20 #include <asm/mmu.h>
21 #include <asm/oprofile_impl.h>
22 #include <asm/prom.h>
23 #include <asm/setup.h>
24 
25 
26 /* Device-tree visible constants follow */
27 #define ISA_V2_07B      2070
28 #define ISA_V3_0B       3000
29 
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 
70 static int hv_mode;
71 
72 static struct {
73 	u64	lpcr;
74 	u64	lpcr_clear;
75 	u64	hfscr;
76 	u64	fscr;
77 } system_registers;
78 
79 static void (*init_pmu_registers)(void);
80 
81 static void __restore_cpu_cpufeatures(void)
82 {
83 	u64 lpcr;
84 
85 	/*
86 	 * LPCR is restored by the power on engine already. It can be changed
87 	 * after early init e.g., by radix enable, and we have no unified API
88 	 * for saving and restoring such SPRs.
89 	 *
90 	 * This ->restore hook should really be removed from idle and register
91 	 * restore moved directly into the idle restore code, because this code
92 	 * doesn't know how idle is implemented or what it needs restored here.
93 	 *
94 	 * The best we can do to accommodate secondary boot and idle restore
95 	 * for now is "or" LPCR with existing.
96 	 */
97 	lpcr = mfspr(SPRN_LPCR);
98 	lpcr |= system_registers.lpcr;
99 	lpcr &= ~system_registers.lpcr_clear;
100 	mtspr(SPRN_LPCR, lpcr);
101 	if (hv_mode) {
102 		mtspr(SPRN_LPID, 0);
103 		mtspr(SPRN_HFSCR, system_registers.hfscr);
104 		mtspr(SPRN_PCR, PCR_MASK);
105 	}
106 	mtspr(SPRN_FSCR, system_registers.fscr);
107 
108 	if (init_pmu_registers)
109 		init_pmu_registers();
110 }
111 
112 static char dt_cpu_name[64];
113 
114 static struct cpu_spec __initdata base_cpu_spec = {
115 	.cpu_name		= NULL,
116 	.cpu_features		= CPU_FTRS_DT_CPU_BASE,
117 	.cpu_user_features	= COMMON_USER_BASE,
118 	.cpu_user_features2	= COMMON_USER2_BASE,
119 	.mmu_features		= 0,
120 	.icache_bsize		= 32, /* minimum block size, fixed by */
121 	.dcache_bsize		= 32, /* cache info init.             */
122 	.num_pmcs		= 0,
123 	.pmc_type		= PPC_PMC_DEFAULT,
124 	.oprofile_cpu_type	= NULL,
125 	.oprofile_type		= PPC_OPROFILE_INVALID,
126 	.cpu_setup		= NULL,
127 	.cpu_restore		= __restore_cpu_cpufeatures,
128 	.machine_check_early	= NULL,
129 	.platform		= NULL,
130 };
131 
132 static void __init cpufeatures_setup_cpu(void)
133 {
134 	set_cur_cpu_spec(&base_cpu_spec);
135 
136 	cur_cpu_spec->pvr_mask = -1;
137 	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
138 
139 	/* Initialize the base environment -- clear FSCR/HFSCR.  */
140 	hv_mode = !!(mfmsr() & MSR_HV);
141 	if (hv_mode) {
142 		/* CPU_FTR_HVMODE is used early in PACA setup */
143 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
144 		mtspr(SPRN_HFSCR, 0);
145 	}
146 	mtspr(SPRN_FSCR, 0);
147 	mtspr(SPRN_PCR, PCR_MASK);
148 
149 	/*
150 	 * LPCR does not get cleared, to match behaviour with secondaries
151 	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
152 	 * could clear LPCR too.
153 	 */
154 }
155 
156 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
157 {
158 	if (f->hv_support == HV_SUPPORT_NONE) {
159 	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
160 		u64 hfscr = mfspr(SPRN_HFSCR);
161 		hfscr |= 1UL << f->hfscr_bit_nr;
162 		mtspr(SPRN_HFSCR, hfscr);
163 	} else {
164 		/* Does not have a known recipe */
165 		return 0;
166 	}
167 
168 	if (f->os_support == OS_SUPPORT_NONE) {
169 	} else if (f->os_support & OS_SUPPORT_FSCR) {
170 		u64 fscr = mfspr(SPRN_FSCR);
171 		fscr |= 1UL << f->fscr_bit_nr;
172 		mtspr(SPRN_FSCR, fscr);
173 	} else {
174 		/* Does not have a known recipe */
175 		return 0;
176 	}
177 
178 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
179 		uint32_t word = f->hwcap_bit_nr / 32;
180 		uint32_t bit = f->hwcap_bit_nr % 32;
181 
182 		if (word == 0)
183 			cur_cpu_spec->cpu_user_features |= 1U << bit;
184 		else if (word == 1)
185 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
186 		else
187 			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
188 	}
189 
190 	return 1;
191 }
192 
193 static int __init feat_enable(struct dt_cpu_feature *f)
194 {
195 	if (f->hv_support != HV_SUPPORT_NONE) {
196 		if (f->hfscr_bit_nr != -1) {
197 			u64 hfscr = mfspr(SPRN_HFSCR);
198 			hfscr |= 1UL << f->hfscr_bit_nr;
199 			mtspr(SPRN_HFSCR, hfscr);
200 		}
201 	}
202 
203 	if (f->os_support != OS_SUPPORT_NONE) {
204 		if (f->fscr_bit_nr != -1) {
205 			u64 fscr = mfspr(SPRN_FSCR);
206 			fscr |= 1UL << f->fscr_bit_nr;
207 			mtspr(SPRN_FSCR, fscr);
208 		}
209 	}
210 
211 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
212 		uint32_t word = f->hwcap_bit_nr / 32;
213 		uint32_t bit = f->hwcap_bit_nr % 32;
214 
215 		if (word == 0)
216 			cur_cpu_spec->cpu_user_features |= 1U << bit;
217 		else if (word == 1)
218 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
219 		else
220 			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
221 	}
222 
223 	return 1;
224 }
225 
226 static int __init feat_disable(struct dt_cpu_feature *f)
227 {
228 	return 0;
229 }
230 
231 static int __init feat_enable_hv(struct dt_cpu_feature *f)
232 {
233 	u64 lpcr;
234 
235 	if (!hv_mode) {
236 		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
237 		return 0;
238 	}
239 
240 	mtspr(SPRN_LPID, 0);
241 
242 	lpcr = mfspr(SPRN_LPCR);
243 	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
244 	mtspr(SPRN_LPCR, lpcr);
245 
246 	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
247 
248 	return 1;
249 }
250 
251 static int __init feat_enable_le(struct dt_cpu_feature *f)
252 {
253 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
254 	return 1;
255 }
256 
257 static int __init feat_enable_smt(struct dt_cpu_feature *f)
258 {
259 	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
260 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
261 	return 1;
262 }
263 
264 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
265 {
266 	u64 lpcr;
267 
268 	/* Set PECE wakeup modes for ISA 207 */
269 	lpcr = mfspr(SPRN_LPCR);
270 	lpcr |=  LPCR_PECE0;
271 	lpcr |=  LPCR_PECE1;
272 	lpcr |=  LPCR_PECE2;
273 	mtspr(SPRN_LPCR, lpcr);
274 
275 	return 1;
276 }
277 
278 static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
279 {
280 	cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
281 
282 	return 1;
283 }
284 
285 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
286 {
287 	u64 lpcr;
288 
289 	/* Set PECE wakeup modes for ISAv3.0B */
290 	lpcr = mfspr(SPRN_LPCR);
291 	lpcr |=  LPCR_PECE0;
292 	lpcr |=  LPCR_PECE1;
293 	lpcr |=  LPCR_PECE2;
294 	mtspr(SPRN_LPCR, lpcr);
295 
296 	return 1;
297 }
298 
299 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
300 {
301 	u64 lpcr;
302 
303 	lpcr = mfspr(SPRN_LPCR);
304 	lpcr &= ~LPCR_ISL;
305 
306 	/* VRMASD */
307 	lpcr |= LPCR_VPM0;
308 	lpcr &= ~LPCR_VPM1;
309 	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
310 	mtspr(SPRN_LPCR, lpcr);
311 
312 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
313 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
314 
315 	return 1;
316 }
317 
318 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
319 {
320 	u64 lpcr;
321 
322 	system_registers.lpcr_clear |= (LPCR_ISL | LPCR_UPRT | LPCR_HR);
323 	lpcr = mfspr(SPRN_LPCR);
324 	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
325 	mtspr(SPRN_LPCR, lpcr);
326 
327 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
328 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
329 
330 	return 1;
331 }
332 
333 
334 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
335 {
336 #ifdef CONFIG_PPC_RADIX_MMU
337 	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
338 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
339 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
340 
341 	return 1;
342 #endif
343 	return 0;
344 }
345 
346 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
347 {
348 	u64 lpcr;
349 
350 	feat_enable(f);
351 
352 	lpcr = mfspr(SPRN_LPCR);
353 	lpcr &= ~LPCR_DPFD;
354 	lpcr |=  (4UL << LPCR_DPFD_SH);
355 	mtspr(SPRN_LPCR, lpcr);
356 
357 	return 1;
358 }
359 
360 static void hfscr_pmu_enable(void)
361 {
362 	u64 hfscr = mfspr(SPRN_HFSCR);
363 	hfscr |= PPC_BIT(60);
364 	mtspr(SPRN_HFSCR, hfscr);
365 }
366 
367 static void init_pmu_power8(void)
368 {
369 	if (hv_mode) {
370 		mtspr(SPRN_MMCRC, 0);
371 		mtspr(SPRN_MMCRH, 0);
372 	}
373 
374 	mtspr(SPRN_MMCRA, 0);
375 	mtspr(SPRN_MMCR0, 0);
376 	mtspr(SPRN_MMCR1, 0);
377 	mtspr(SPRN_MMCR2, 0);
378 	mtspr(SPRN_MMCRS, 0);
379 }
380 
381 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
382 {
383 	cur_cpu_spec->platform = "power8";
384 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
385 
386 	return 1;
387 }
388 
389 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
390 {
391 	hfscr_pmu_enable();
392 
393 	init_pmu_power8();
394 	init_pmu_registers = init_pmu_power8;
395 
396 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
397 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
398 	if (pvr_version_is(PVR_POWER8E))
399 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
400 
401 	cur_cpu_spec->num_pmcs		= 6;
402 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
403 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
404 
405 	return 1;
406 }
407 
408 static void init_pmu_power9(void)
409 {
410 	if (hv_mode)
411 		mtspr(SPRN_MMCRC, 0);
412 
413 	mtspr(SPRN_MMCRA, 0);
414 	mtspr(SPRN_MMCR0, 0);
415 	mtspr(SPRN_MMCR1, 0);
416 	mtspr(SPRN_MMCR2, 0);
417 }
418 
419 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
420 {
421 	cur_cpu_spec->platform = "power9";
422 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
423 
424 	return 1;
425 }
426 
427 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
428 {
429 	hfscr_pmu_enable();
430 
431 	init_pmu_power9();
432 	init_pmu_registers = init_pmu_power9;
433 
434 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
435 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
436 
437 	cur_cpu_spec->num_pmcs		= 6;
438 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
439 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
440 
441 	return 1;
442 }
443 
444 static int __init feat_enable_tm(struct dt_cpu_feature *f)
445 {
446 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
447 	feat_enable(f);
448 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
449 	return 1;
450 #endif
451 	return 0;
452 }
453 
454 static int __init feat_enable_fp(struct dt_cpu_feature *f)
455 {
456 	feat_enable(f);
457 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
458 
459 	return 1;
460 }
461 
462 static int __init feat_enable_vector(struct dt_cpu_feature *f)
463 {
464 #ifdef CONFIG_ALTIVEC
465 	feat_enable(f);
466 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
467 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
468 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
469 
470 	return 1;
471 #endif
472 	return 0;
473 }
474 
475 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
476 {
477 #ifdef CONFIG_VSX
478 	feat_enable(f);
479 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
480 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
481 
482 	return 1;
483 #endif
484 	return 0;
485 }
486 
487 static int __init feat_enable_purr(struct dt_cpu_feature *f)
488 {
489 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
490 
491 	return 1;
492 }
493 
494 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
495 {
496 	/*
497 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
498 	 * historically been related to the PMU facility. This may have
499 	 * to be decoupled if EBB becomes more generic. For now, follow
500 	 * existing convention.
501 	 */
502 	f->hwcap_bit_nr = -1;
503 	feat_enable(f);
504 
505 	return 1;
506 }
507 
508 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
509 {
510 	u64 lpcr;
511 
512 	/* P9 has an HFSCR for privileged state */
513 	feat_enable(f);
514 
515 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
516 
517 	lpcr = mfspr(SPRN_LPCR);
518 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
519 	mtspr(SPRN_LPCR, lpcr);
520 
521 	return 1;
522 }
523 
524 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
525 {
526 	u64 lpcr;
527 
528 	/*
529 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
530 	 * are always delivered as hypervisor virtualization interrupts (HVI)
531 	 * rather than EE.
532 	 *
533 	 * However LPES0 is not set here, in the chance that an EE does get
534 	 * delivered to the host somehow, the EE handler would not expect it
535 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
536 	 * happen if there is a bug in interrupt controller code, or IC is
537 	 * misconfigured in systemsim.
538 	 */
539 
540 	lpcr = mfspr(SPRN_LPCR);
541 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
542 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
543 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
544 	mtspr(SPRN_LPCR, lpcr);
545 
546 	return 1;
547 }
548 
549 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
550 {
551 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
552 
553 	return 1;
554 }
555 
556 struct dt_cpu_feature_match {
557 	const char *name;
558 	int (*enable)(struct dt_cpu_feature *f);
559 	u64 cpu_ftr_bit_mask;
560 };
561 
562 static struct dt_cpu_feature_match __initdata
563 		dt_cpu_feature_match_table[] = {
564 	{"hypervisor", feat_enable_hv, 0},
565 	{"big-endian", feat_enable, 0},
566 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
567 	{"smt", feat_enable_smt, 0},
568 	{"interrupt-facilities", feat_enable, 0},
569 	{"timer-facilities", feat_enable, 0},
570 	{"timer-facilities-v3", feat_enable, 0},
571 	{"debug-facilities", feat_enable, 0},
572 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
573 	{"branch-tracing", feat_enable, 0},
574 	{"floating-point", feat_enable_fp, 0},
575 	{"vector", feat_enable_vector, 0},
576 	{"vector-scalar", feat_enable_vsx, 0},
577 	{"vector-scalar-v3", feat_enable, 0},
578 	{"decimal-floating-point", feat_enable, 0},
579 	{"decimal-integer", feat_enable, 0},
580 	{"quadword-load-store", feat_enable, 0},
581 	{"vector-crypto", feat_enable, 0},
582 	{"mmu-hash", feat_enable_mmu_hash, 0},
583 	{"mmu-radix", feat_enable_mmu_radix, 0},
584 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
585 	{"virtual-page-class-key-protection", feat_enable, 0},
586 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
587 	{"transactional-memory-v3", feat_enable_tm, 0},
588 	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
589 	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
590 	{"idle-nap", feat_enable_idle_nap, 0},
591 	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
592 	{"idle-stop", feat_enable_idle_stop, 0},
593 	{"machine-check-power8", feat_enable_mce_power8, 0},
594 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
595 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
596 	{"event-based-branch", feat_enable_ebb, 0},
597 	{"target-address-register", feat_enable, 0},
598 	{"branch-history-rolling-buffer", feat_enable, 0},
599 	{"control-register", feat_enable, CPU_FTR_CTRL},
600 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
601 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
602 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
603 	{"no-execute", feat_enable, 0},
604 	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
605 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
606 	{"coprocessor-icswx", feat_enable, 0},
607 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
608 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
609 	{"wait", feat_enable, 0},
610 	{"atomic-memory-operations", feat_enable, 0},
611 	{"branch-v3", feat_enable, 0},
612 	{"copy-paste", feat_enable, 0},
613 	{"decimal-floating-point-v3", feat_enable, 0},
614 	{"decimal-integer-v3", feat_enable, 0},
615 	{"fixed-point-v3", feat_enable, 0},
616 	{"floating-point-v3", feat_enable, 0},
617 	{"group-start-register", feat_enable, 0},
618 	{"pc-relative-addressing", feat_enable, 0},
619 	{"machine-check-power9", feat_enable_mce_power9, 0},
620 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
621 	{"event-based-branch-v3", feat_enable, 0},
622 	{"random-number-generator", feat_enable, 0},
623 	{"system-call-vectored", feat_disable, 0},
624 	{"trace-interrupt-v3", feat_enable, 0},
625 	{"vector-v3", feat_enable, 0},
626 	{"vector-binary128", feat_enable, 0},
627 	{"vector-binary16", feat_enable, 0},
628 	{"wait-v3", feat_enable, 0},
629 };
630 
631 static bool __initdata using_dt_cpu_ftrs;
632 static bool __initdata enable_unknown = true;
633 
634 static int __init dt_cpu_ftrs_parse(char *str)
635 {
636 	if (!str)
637 		return 0;
638 
639 	if (!strcmp(str, "off"))
640 		using_dt_cpu_ftrs = false;
641 	else if (!strcmp(str, "known"))
642 		enable_unknown = false;
643 	else
644 		return 1;
645 
646 	return 0;
647 }
648 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
649 
650 static void __init cpufeatures_setup_start(u32 isa)
651 {
652 	pr_info("setup for ISA %d\n", isa);
653 
654 	if (isa >= 3000) {
655 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
656 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
657 	}
658 }
659 
660 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
661 {
662 	const struct dt_cpu_feature_match *m;
663 	bool known = false;
664 	int i;
665 
666 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
667 		m = &dt_cpu_feature_match_table[i];
668 		if (!strcmp(f->name, m->name)) {
669 			known = true;
670 			if (m->enable(f)) {
671 				cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
672 				break;
673 			}
674 
675 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
676 				f->name);
677 			return false;
678 		}
679 	}
680 
681 	if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
682 		pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
683 			f->name);
684 		return false;
685 	}
686 
687 	if (known)
688 		pr_debug("enabling: %s\n", f->name);
689 	else
690 		pr_debug("enabling: %s (unknown)\n", f->name);
691 
692 	return true;
693 }
694 
695 /*
696  * Handle POWER9 broadcast tlbie invalidation issue using
697  * cpu feature flag.
698  */
699 static __init void update_tlbie_feature_flag(unsigned long pvr)
700 {
701 	if (PVR_VER(pvr) == PVR_POWER9) {
702 		/*
703 		 * Set the tlbie feature flag for anything below
704 		 * Nimbus DD 2.3 and Cumulus DD 1.3
705 		 */
706 		if ((pvr & 0xe000) == 0) {
707 			/* Nimbus */
708 			if ((pvr & 0xfff) < 0x203)
709 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
710 		} else if ((pvr & 0xc000) == 0) {
711 			/* Cumulus */
712 			if ((pvr & 0xfff) < 0x103)
713 				cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
714 		} else {
715 			WARN_ONCE(1, "Unknown PVR");
716 			cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
717 		}
718 
719 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
720 	}
721 }
722 
723 static __init void cpufeatures_cpu_quirks(void)
724 {
725 	unsigned long version = mfspr(SPRN_PVR);
726 
727 	/*
728 	 * Not all quirks can be derived from the cpufeatures device tree.
729 	 */
730 	if ((version & 0xffffefff) == 0x004e0200) {
731 		/* DD2.0 has no feature flag */
732 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
733 	} else if ((version & 0xffffefff) == 0x004e0201) {
734 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
735 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
736 	} else if ((version & 0xffffefff) == 0x004e0202) {
737 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
738 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
739 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
740 	} else if ((version & 0xffff0000) == 0x004e0000) {
741 		/* DD2.1 and up have DD2_1 */
742 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
743 	}
744 
745 	if ((version & 0xffff0000) == 0x004e0000) {
746 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
747 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
748 	}
749 
750 	update_tlbie_feature_flag(version);
751 	/*
752 	 * PKEY was not in the initial base or feature node
753 	 * specification, but it should become optional in the next
754 	 * cpu feature version sequence.
755 	 */
756 	cur_cpu_spec->cpu_features |= CPU_FTR_PKEY;
757 }
758 
759 static void __init cpufeatures_setup_finished(void)
760 {
761 	cpufeatures_cpu_quirks();
762 
763 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
764 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
765 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
766 	}
767 
768 	/* Make sure powerpc_base_platform is non-NULL */
769 	powerpc_base_platform = cur_cpu_spec->platform;
770 
771 	system_registers.lpcr = mfspr(SPRN_LPCR);
772 	system_registers.hfscr = mfspr(SPRN_HFSCR);
773 	system_registers.fscr = mfspr(SPRN_FSCR);
774 
775 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
776 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
777 }
778 
779 static int __init disabled_on_cmdline(void)
780 {
781 	unsigned long root, chosen;
782 	const char *p;
783 
784 	root = of_get_flat_dt_root();
785 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
786 	if (chosen == -FDT_ERR_NOTFOUND)
787 		return false;
788 
789 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
790 	if (!p)
791 		return false;
792 
793 	if (strstr(p, "dt_cpu_ftrs=off"))
794 		return true;
795 
796 	return false;
797 }
798 
799 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
800 					int depth, void *data)
801 {
802 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
803 	    && of_get_flat_dt_prop(node, "isa", NULL))
804 		return 1;
805 
806 	return 0;
807 }
808 
809 bool __init dt_cpu_ftrs_in_use(void)
810 {
811 	return using_dt_cpu_ftrs;
812 }
813 
814 bool __init dt_cpu_ftrs_init(void *fdt)
815 {
816 	using_dt_cpu_ftrs = false;
817 
818 	/* Setup and verify the FDT, if it fails we just bail */
819 	if (!early_init_dt_verify(fdt))
820 		return false;
821 
822 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
823 		return false;
824 
825 	if (disabled_on_cmdline())
826 		return false;
827 
828 	cpufeatures_setup_cpu();
829 
830 	using_dt_cpu_ftrs = true;
831 	return true;
832 }
833 
834 static int nr_dt_cpu_features;
835 static struct dt_cpu_feature *dt_cpu_features;
836 
837 static int __init process_cpufeatures_node(unsigned long node,
838 					  const char *uname, int i)
839 {
840 	const __be32 *prop;
841 	struct dt_cpu_feature *f;
842 	int len;
843 
844 	f = &dt_cpu_features[i];
845 
846 	f->node = node;
847 
848 	f->name = uname;
849 
850 	prop = of_get_flat_dt_prop(node, "isa", &len);
851 	if (!prop) {
852 		pr_warn("%s: missing isa property\n", uname);
853 		return 0;
854 	}
855 	f->isa = be32_to_cpup(prop);
856 
857 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
858 	if (!prop) {
859 		pr_warn("%s: missing usable-privilege property", uname);
860 		return 0;
861 	}
862 	f->usable_privilege = be32_to_cpup(prop);
863 
864 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
865 	if (prop)
866 		f->hv_support = be32_to_cpup(prop);
867 	else
868 		f->hv_support = HV_SUPPORT_NONE;
869 
870 	prop = of_get_flat_dt_prop(node, "os-support", &len);
871 	if (prop)
872 		f->os_support = be32_to_cpup(prop);
873 	else
874 		f->os_support = OS_SUPPORT_NONE;
875 
876 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
877 	if (prop)
878 		f->hfscr_bit_nr = be32_to_cpup(prop);
879 	else
880 		f->hfscr_bit_nr = -1;
881 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
882 	if (prop)
883 		f->fscr_bit_nr = be32_to_cpup(prop);
884 	else
885 		f->fscr_bit_nr = -1;
886 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
887 	if (prop)
888 		f->hwcap_bit_nr = be32_to_cpup(prop);
889 	else
890 		f->hwcap_bit_nr = -1;
891 
892 	if (f->usable_privilege & USABLE_HV) {
893 		if (!(mfmsr() & MSR_HV)) {
894 			pr_warn("%s: HV feature passed to guest\n", uname);
895 			return 0;
896 		}
897 
898 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
899 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
900 			return 0;
901 		}
902 
903 		if (f->hv_support == HV_SUPPORT_HFSCR) {
904 			if (f->hfscr_bit_nr == -1) {
905 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
906 				return 0;
907 			}
908 		}
909 	} else {
910 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
911 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
912 			return 0;
913 		}
914 	}
915 
916 	if (f->usable_privilege & USABLE_OS) {
917 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
918 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
919 			return 0;
920 		}
921 
922 		if (f->os_support == OS_SUPPORT_FSCR) {
923 			if (f->fscr_bit_nr == -1) {
924 				pr_warn("%s: missing fscr_bit_nr\n", uname);
925 				return 0;
926 			}
927 		}
928 	} else {
929 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
930 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
931 			return 0;
932 		}
933 	}
934 
935 	if (!(f->usable_privilege & USABLE_PR)) {
936 		if (f->hwcap_bit_nr != -1) {
937 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
938 			return 0;
939 		}
940 	}
941 
942 	/* Do all the independent features in the first pass */
943 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
944 		if (cpufeatures_process_feature(f))
945 			f->enabled = 1;
946 		else
947 			f->disabled = 1;
948 	}
949 
950 	return 0;
951 }
952 
953 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
954 {
955 	const __be32 *prop;
956 	int len;
957 	int nr_deps;
958 	int i;
959 
960 	if (f->enabled || f->disabled)
961 		return;
962 
963 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
964 	if (!prop) {
965 		pr_warn("%s: missing dependencies property", f->name);
966 		return;
967 	}
968 
969 	nr_deps = len / sizeof(int);
970 
971 	for (i = 0; i < nr_deps; i++) {
972 		unsigned long phandle = be32_to_cpu(prop[i]);
973 		int j;
974 
975 		for (j = 0; j < nr_dt_cpu_features; j++) {
976 			struct dt_cpu_feature *d = &dt_cpu_features[j];
977 
978 			if (of_get_flat_dt_phandle(d->node) == phandle) {
979 				cpufeatures_deps_enable(d);
980 				if (d->disabled) {
981 					f->disabled = 1;
982 					return;
983 				}
984 			}
985 		}
986 	}
987 
988 	if (cpufeatures_process_feature(f))
989 		f->enabled = 1;
990 	else
991 		f->disabled = 1;
992 }
993 
994 static int __init scan_cpufeatures_subnodes(unsigned long node,
995 					  const char *uname,
996 					  void *data)
997 {
998 	int *count = data;
999 
1000 	process_cpufeatures_node(node, uname, *count);
1001 
1002 	(*count)++;
1003 
1004 	return 0;
1005 }
1006 
1007 static int __init count_cpufeatures_subnodes(unsigned long node,
1008 					  const char *uname,
1009 					  void *data)
1010 {
1011 	int *count = data;
1012 
1013 	(*count)++;
1014 
1015 	return 0;
1016 }
1017 
1018 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1019 					    *uname, int depth, void *data)
1020 {
1021 	const __be32 *prop;
1022 	int count, i;
1023 	u32 isa;
1024 
1025 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
1026 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1027 		return 0;
1028 
1029 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1030 	if (!prop)
1031 		/* We checked before, "can't happen" */
1032 		return 0;
1033 
1034 	isa = be32_to_cpup(prop);
1035 
1036 	/* Count and allocate space for cpu features */
1037 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1038 						&nr_dt_cpu_features);
1039 	dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1040 	if (!dt_cpu_features)
1041 		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1042 		      __func__,
1043 		      sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1044 		      PAGE_SIZE);
1045 
1046 	cpufeatures_setup_start(isa);
1047 
1048 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1049 	count = 0;
1050 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1051 
1052 	/* Recursive enable remaining features with dependencies */
1053 	for (i = 0; i < nr_dt_cpu_features; i++) {
1054 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1055 
1056 		cpufeatures_deps_enable(f);
1057 	}
1058 
1059 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1060 	if (prop && strlen((char *)prop) != 0) {
1061 		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1062 		cur_cpu_spec->cpu_name = dt_cpu_name;
1063 	}
1064 
1065 	cpufeatures_setup_finished();
1066 
1067 	memblock_free(__pa(dt_cpu_features),
1068 			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1069 
1070 	return 0;
1071 }
1072 
1073 void __init dt_cpu_ftrs_scan(void)
1074 {
1075 	if (!using_dt_cpu_ftrs)
1076 		return;
1077 
1078 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1079 }
1080