xref: /openbmc/linux/arch/powerpc/kernel/dt_cpu_ftrs.c (revision e33bbe69149b802c0c77bfb822685772f85388ca)
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 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 	}
105 	mtspr(SPRN_FSCR, system_registers.fscr);
106 
107 	if (init_pmu_registers)
108 		init_pmu_registers();
109 }
110 
111 static char dt_cpu_name[64];
112 
113 static struct cpu_spec __initdata base_cpu_spec = {
114 	.cpu_name		= NULL,
115 	.cpu_features		= CPU_FTRS_DT_CPU_BASE,
116 	.cpu_user_features	= COMMON_USER_BASE,
117 	.cpu_user_features2	= COMMON_USER2_BASE,
118 	.mmu_features		= 0,
119 	.icache_bsize		= 32, /* minimum block size, fixed by */
120 	.dcache_bsize		= 32, /* cache info init.             */
121 	.num_pmcs		= 0,
122 	.pmc_type		= PPC_PMC_DEFAULT,
123 	.oprofile_cpu_type	= NULL,
124 	.oprofile_type		= PPC_OPROFILE_INVALID,
125 	.cpu_setup		= NULL,
126 	.cpu_restore		= __restore_cpu_cpufeatures,
127 	.machine_check_early	= NULL,
128 	.platform		= NULL,
129 };
130 
131 static void __init cpufeatures_setup_cpu(void)
132 {
133 	set_cur_cpu_spec(&base_cpu_spec);
134 
135 	cur_cpu_spec->pvr_mask = -1;
136 	cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
137 
138 	/* Initialize the base environment -- clear FSCR/HFSCR.  */
139 	hv_mode = !!(mfmsr() & MSR_HV);
140 	if (hv_mode) {
141 		/* CPU_FTR_HVMODE is used early in PACA setup */
142 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
143 		mtspr(SPRN_HFSCR, 0);
144 	}
145 	mtspr(SPRN_FSCR, 0);
146 
147 	/*
148 	 * LPCR does not get cleared, to match behaviour with secondaries
149 	 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
150 	 * could clear LPCR too.
151 	 */
152 }
153 
154 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
155 {
156 	if (f->hv_support == HV_SUPPORT_NONE) {
157 	} else if (f->hv_support & HV_SUPPORT_HFSCR) {
158 		u64 hfscr = mfspr(SPRN_HFSCR);
159 		hfscr |= 1UL << f->hfscr_bit_nr;
160 		mtspr(SPRN_HFSCR, hfscr);
161 	} else {
162 		/* Does not have a known recipe */
163 		return 0;
164 	}
165 
166 	if (f->os_support == OS_SUPPORT_NONE) {
167 	} else if (f->os_support & OS_SUPPORT_FSCR) {
168 		u64 fscr = mfspr(SPRN_FSCR);
169 		fscr |= 1UL << f->fscr_bit_nr;
170 		mtspr(SPRN_FSCR, fscr);
171 	} else {
172 		/* Does not have a known recipe */
173 		return 0;
174 	}
175 
176 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
177 		uint32_t word = f->hwcap_bit_nr / 32;
178 		uint32_t bit = f->hwcap_bit_nr % 32;
179 
180 		if (word == 0)
181 			cur_cpu_spec->cpu_user_features |= 1U << bit;
182 		else if (word == 1)
183 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
184 		else
185 			pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
186 	}
187 
188 	return 1;
189 }
190 
191 static int __init feat_enable(struct dt_cpu_feature *f)
192 {
193 	if (f->hv_support != HV_SUPPORT_NONE) {
194 		if (f->hfscr_bit_nr != -1) {
195 			u64 hfscr = mfspr(SPRN_HFSCR);
196 			hfscr |= 1UL << f->hfscr_bit_nr;
197 			mtspr(SPRN_HFSCR, hfscr);
198 		}
199 	}
200 
201 	if (f->os_support != OS_SUPPORT_NONE) {
202 		if (f->fscr_bit_nr != -1) {
203 			u64 fscr = mfspr(SPRN_FSCR);
204 			fscr |= 1UL << f->fscr_bit_nr;
205 			mtspr(SPRN_FSCR, fscr);
206 		}
207 	}
208 
209 	if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
210 		uint32_t word = f->hwcap_bit_nr / 32;
211 		uint32_t bit = f->hwcap_bit_nr % 32;
212 
213 		if (word == 0)
214 			cur_cpu_spec->cpu_user_features |= 1U << bit;
215 		else if (word == 1)
216 			cur_cpu_spec->cpu_user_features2 |= 1U << bit;
217 		else
218 			pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
219 	}
220 
221 	return 1;
222 }
223 
224 static int __init feat_disable(struct dt_cpu_feature *f)
225 {
226 	return 0;
227 }
228 
229 static int __init feat_enable_hv(struct dt_cpu_feature *f)
230 {
231 	u64 lpcr;
232 
233 	if (!hv_mode) {
234 		pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
235 		return 0;
236 	}
237 
238 	mtspr(SPRN_LPID, 0);
239 
240 	lpcr = mfspr(SPRN_LPCR);
241 	lpcr &=  ~LPCR_LPES0; /* HV external interrupts */
242 	mtspr(SPRN_LPCR, lpcr);
243 
244 	cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
245 
246 	return 1;
247 }
248 
249 static int __init feat_enable_le(struct dt_cpu_feature *f)
250 {
251 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
252 	return 1;
253 }
254 
255 static int __init feat_enable_smt(struct dt_cpu_feature *f)
256 {
257 	cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
258 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
259 	return 1;
260 }
261 
262 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
263 {
264 	u64 lpcr;
265 
266 	/* Set PECE wakeup modes for ISA 207 */
267 	lpcr = mfspr(SPRN_LPCR);
268 	lpcr |=  LPCR_PECE0;
269 	lpcr |=  LPCR_PECE1;
270 	lpcr |=  LPCR_PECE2;
271 	mtspr(SPRN_LPCR, lpcr);
272 
273 	return 1;
274 }
275 
276 static int __init feat_enable_align_dsisr(struct dt_cpu_feature *f)
277 {
278 	cur_cpu_spec->cpu_features &= ~CPU_FTR_NODSISRALIGN;
279 
280 	return 1;
281 }
282 
283 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
284 {
285 	u64 lpcr;
286 
287 	/* Set PECE wakeup modes for ISAv3.0B */
288 	lpcr = mfspr(SPRN_LPCR);
289 	lpcr |=  LPCR_PECE0;
290 	lpcr |=  LPCR_PECE1;
291 	lpcr |=  LPCR_PECE2;
292 	mtspr(SPRN_LPCR, lpcr);
293 
294 	return 1;
295 }
296 
297 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
298 {
299 	u64 lpcr;
300 
301 	lpcr = mfspr(SPRN_LPCR);
302 	lpcr &= ~LPCR_ISL;
303 
304 	/* VRMASD */
305 	lpcr |= LPCR_VPM0;
306 	lpcr &= ~LPCR_VPM1;
307 	lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
308 	mtspr(SPRN_LPCR, lpcr);
309 
310 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
311 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
312 
313 	return 1;
314 }
315 
316 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
317 {
318 	u64 lpcr;
319 
320 	system_registers.lpcr_clear |= (LPCR_ISL | LPCR_UPRT | LPCR_HR);
321 	lpcr = mfspr(SPRN_LPCR);
322 	lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
323 	mtspr(SPRN_LPCR, lpcr);
324 
325 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
326 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
327 
328 	return 1;
329 }
330 
331 
332 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
333 {
334 #ifdef CONFIG_PPC_RADIX_MMU
335 	cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
336 	cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
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 	feat_enable(f);
349 
350 	lpcr = mfspr(SPRN_LPCR);
351 	lpcr &= ~LPCR_DPFD;
352 	lpcr |=  (4UL << LPCR_DPFD_SH);
353 	mtspr(SPRN_LPCR, lpcr);
354 
355 	return 1;
356 }
357 
358 static void hfscr_pmu_enable(void)
359 {
360 	u64 hfscr = mfspr(SPRN_HFSCR);
361 	hfscr |= PPC_BIT(60);
362 	mtspr(SPRN_HFSCR, hfscr);
363 }
364 
365 static void init_pmu_power8(void)
366 {
367 	if (hv_mode) {
368 		mtspr(SPRN_MMCRC, 0);
369 		mtspr(SPRN_MMCRH, 0);
370 	}
371 
372 	mtspr(SPRN_MMCRA, 0);
373 	mtspr(SPRN_MMCR0, 0);
374 	mtspr(SPRN_MMCR1, 0);
375 	mtspr(SPRN_MMCR2, 0);
376 	mtspr(SPRN_MMCRS, 0);
377 }
378 
379 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
380 {
381 	cur_cpu_spec->platform = "power8";
382 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
383 
384 	return 1;
385 }
386 
387 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
388 {
389 	hfscr_pmu_enable();
390 
391 	init_pmu_power8();
392 	init_pmu_registers = init_pmu_power8;
393 
394 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
395 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
396 	if (pvr_version_is(PVR_POWER8E))
397 		cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
398 
399 	cur_cpu_spec->num_pmcs		= 6;
400 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
401 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power8";
402 
403 	return 1;
404 }
405 
406 static void init_pmu_power9(void)
407 {
408 	if (hv_mode)
409 		mtspr(SPRN_MMCRC, 0);
410 
411 	mtspr(SPRN_MMCRA, 0);
412 	mtspr(SPRN_MMCR0, 0);
413 	mtspr(SPRN_MMCR1, 0);
414 	mtspr(SPRN_MMCR2, 0);
415 }
416 
417 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
418 {
419 	cur_cpu_spec->platform = "power9";
420 	cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
421 
422 	return 1;
423 }
424 
425 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
426 {
427 	hfscr_pmu_enable();
428 
429 	init_pmu_power9();
430 	init_pmu_registers = init_pmu_power9;
431 
432 	cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
433 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
434 
435 	cur_cpu_spec->num_pmcs		= 6;
436 	cur_cpu_spec->pmc_type		= PPC_PMC_IBM;
437 	cur_cpu_spec->oprofile_cpu_type	= "ppc64/power9";
438 
439 	return 1;
440 }
441 
442 static int __init feat_enable_tm(struct dt_cpu_feature *f)
443 {
444 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
445 	feat_enable(f);
446 	cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
447 	return 1;
448 #endif
449 	return 0;
450 }
451 
452 static int __init feat_enable_fp(struct dt_cpu_feature *f)
453 {
454 	feat_enable(f);
455 	cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
456 
457 	return 1;
458 }
459 
460 static int __init feat_enable_vector(struct dt_cpu_feature *f)
461 {
462 #ifdef CONFIG_ALTIVEC
463 	feat_enable(f);
464 	cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
465 	cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
466 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
467 
468 	return 1;
469 #endif
470 	return 0;
471 }
472 
473 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
474 {
475 #ifdef CONFIG_VSX
476 	feat_enable(f);
477 	cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
478 	cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
479 
480 	return 1;
481 #endif
482 	return 0;
483 }
484 
485 static int __init feat_enable_purr(struct dt_cpu_feature *f)
486 {
487 	cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
488 
489 	return 1;
490 }
491 
492 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
493 {
494 	/*
495 	 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
496 	 * historically been related to the PMU facility. This may have
497 	 * to be decoupled if EBB becomes more generic. For now, follow
498 	 * existing convention.
499 	 */
500 	f->hwcap_bit_nr = -1;
501 	feat_enable(f);
502 
503 	return 1;
504 }
505 
506 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
507 {
508 	u64 lpcr;
509 
510 	/* P9 has an HFSCR for privileged state */
511 	feat_enable(f);
512 
513 	cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
514 
515 	lpcr = mfspr(SPRN_LPCR);
516 	lpcr |=  LPCR_PECEDH; /* hyp doorbell wakeup */
517 	mtspr(SPRN_LPCR, lpcr);
518 
519 	return 1;
520 }
521 
522 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
523 {
524 	u64 lpcr;
525 
526 	/*
527 	 * POWER9 XIVE interrupts including in OPAL XICS compatibility
528 	 * are always delivered as hypervisor virtualization interrupts (HVI)
529 	 * rather than EE.
530 	 *
531 	 * However LPES0 is not set here, in the chance that an EE does get
532 	 * delivered to the host somehow, the EE handler would not expect it
533 	 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
534 	 * happen if there is a bug in interrupt controller code, or IC is
535 	 * misconfigured in systemsim.
536 	 */
537 
538 	lpcr = mfspr(SPRN_LPCR);
539 	lpcr |= LPCR_HVICE;	/* enable hvi interrupts */
540 	lpcr |= LPCR_HEIC;	/* disable ee interrupts when MSR_HV */
541 	lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
542 	mtspr(SPRN_LPCR, lpcr);
543 
544 	return 1;
545 }
546 
547 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
548 {
549 	cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
550 
551 	return 1;
552 }
553 
554 struct dt_cpu_feature_match {
555 	const char *name;
556 	int (*enable)(struct dt_cpu_feature *f);
557 	u64 cpu_ftr_bit_mask;
558 };
559 
560 static struct dt_cpu_feature_match __initdata
561 		dt_cpu_feature_match_table[] = {
562 	{"hypervisor", feat_enable_hv, 0},
563 	{"big-endian", feat_enable, 0},
564 	{"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
565 	{"smt", feat_enable_smt, 0},
566 	{"interrupt-facilities", feat_enable, 0},
567 	{"timer-facilities", feat_enable, 0},
568 	{"timer-facilities-v3", feat_enable, 0},
569 	{"debug-facilities", feat_enable, 0},
570 	{"come-from-address-register", feat_enable, CPU_FTR_CFAR},
571 	{"branch-tracing", feat_enable, 0},
572 	{"floating-point", feat_enable_fp, 0},
573 	{"vector", feat_enable_vector, 0},
574 	{"vector-scalar", feat_enable_vsx, 0},
575 	{"vector-scalar-v3", feat_enable, 0},
576 	{"decimal-floating-point", feat_enable, 0},
577 	{"decimal-integer", feat_enable, 0},
578 	{"quadword-load-store", feat_enable, 0},
579 	{"vector-crypto", feat_enable, 0},
580 	{"mmu-hash", feat_enable_mmu_hash, 0},
581 	{"mmu-radix", feat_enable_mmu_radix, 0},
582 	{"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
583 	{"virtual-page-class-key-protection", feat_enable, 0},
584 	{"transactional-memory", feat_enable_tm, CPU_FTR_TM},
585 	{"transactional-memory-v3", feat_enable_tm, 0},
586 	{"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
587 	{"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
588 	{"idle-nap", feat_enable_idle_nap, 0},
589 	{"alignment-interrupt-dsisr", feat_enable_align_dsisr, 0},
590 	{"idle-stop", feat_enable_idle_stop, 0},
591 	{"machine-check-power8", feat_enable_mce_power8, 0},
592 	{"performance-monitor-power8", feat_enable_pmu_power8, 0},
593 	{"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
594 	{"event-based-branch", feat_enable_ebb, 0},
595 	{"target-address-register", feat_enable, 0},
596 	{"branch-history-rolling-buffer", feat_enable, 0},
597 	{"control-register", feat_enable, CPU_FTR_CTRL},
598 	{"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
599 	{"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
600 	{"processor-utilization-of-resources-register", feat_enable_purr, 0},
601 	{"no-execute", feat_enable, 0},
602 	{"strong-access-ordering", feat_enable, CPU_FTR_SAO},
603 	{"cache-inhibited-large-page", feat_enable_large_ci, 0},
604 	{"coprocessor-icswx", feat_enable, 0},
605 	{"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
606 	{"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
607 	{"wait", feat_enable, 0},
608 	{"atomic-memory-operations", feat_enable, 0},
609 	{"branch-v3", feat_enable, 0},
610 	{"copy-paste", feat_enable, 0},
611 	{"decimal-floating-point-v3", feat_enable, 0},
612 	{"decimal-integer-v3", feat_enable, 0},
613 	{"fixed-point-v3", feat_enable, 0},
614 	{"floating-point-v3", feat_enable, 0},
615 	{"group-start-register", feat_enable, 0},
616 	{"pc-relative-addressing", feat_enable, 0},
617 	{"machine-check-power9", feat_enable_mce_power9, 0},
618 	{"performance-monitor-power9", feat_enable_pmu_power9, 0},
619 	{"event-based-branch-v3", feat_enable, 0},
620 	{"random-number-generator", feat_enable, 0},
621 	{"system-call-vectored", feat_disable, 0},
622 	{"trace-interrupt-v3", feat_enable, 0},
623 	{"vector-v3", feat_enable, 0},
624 	{"vector-binary128", feat_enable, 0},
625 	{"vector-binary16", feat_enable, 0},
626 	{"wait-v3", feat_enable, 0},
627 };
628 
629 static bool __initdata using_dt_cpu_ftrs;
630 static bool __initdata enable_unknown = true;
631 
632 static int __init dt_cpu_ftrs_parse(char *str)
633 {
634 	if (!str)
635 		return 0;
636 
637 	if (!strcmp(str, "off"))
638 		using_dt_cpu_ftrs = false;
639 	else if (!strcmp(str, "known"))
640 		enable_unknown = false;
641 	else
642 		return 1;
643 
644 	return 0;
645 }
646 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
647 
648 static void __init cpufeatures_setup_start(u32 isa)
649 {
650 	pr_info("setup for ISA %d\n", isa);
651 
652 	if (isa >= 3000) {
653 		cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
654 		cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
655 	}
656 }
657 
658 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
659 {
660 	const struct dt_cpu_feature_match *m;
661 	bool known = false;
662 	int i;
663 
664 	for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
665 		m = &dt_cpu_feature_match_table[i];
666 		if (!strcmp(f->name, m->name)) {
667 			known = true;
668 			if (m->enable(f))
669 				break;
670 
671 			pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
672 				f->name);
673 			return false;
674 		}
675 	}
676 
677 	if (!known && enable_unknown) {
678 		if (!feat_try_enable_unknown(f)) {
679 			pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
680 				f->name);
681 			return false;
682 		}
683 	}
684 
685 	if (m->cpu_ftr_bit_mask)
686 		cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
687 
688 	if (known)
689 		pr_debug("enabling: %s\n", f->name);
690 	else
691 		pr_debug("enabling: %s (unknown)\n", f->name);
692 
693 	return true;
694 }
695 
696 static __init void cpufeatures_cpu_quirks(void)
697 {
698 	int version = mfspr(SPRN_PVR);
699 
700 	/*
701 	 * Not all quirks can be derived from the cpufeatures device tree.
702 	 */
703 	if ((version & 0xffffff00) == 0x004e0100)
704 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD1;
705 	else if ((version & 0xffffefff) == 0x004e0200)
706 		; /* DD2.0 has no feature flag */
707 	else if ((version & 0xffffefff) == 0x004e0201)
708 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
709 	else if ((version & 0xffffefff) == 0x004e0202) {
710 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
711 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
712 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
713 	} else /* DD2.1 and up have DD2_1 */
714 		cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
715 
716 	if ((version & 0xffff0000) == 0x004e0000) {
717 		cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
718 		cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_BUG;
719 	}
720 
721 	/*
722 	 * PKEY was not in the initial base or feature node
723 	 * specification, but it should become optional in the next
724 	 * cpu feature version sequence.
725 	 */
726 	cur_cpu_spec->cpu_features |= CPU_FTR_PKEY;
727 }
728 
729 static void __init cpufeatures_setup_finished(void)
730 {
731 	cpufeatures_cpu_quirks();
732 
733 	if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
734 		pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
735 		cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
736 	}
737 
738 	/* Make sure powerpc_base_platform is non-NULL */
739 	powerpc_base_platform = cur_cpu_spec->platform;
740 
741 	system_registers.lpcr = mfspr(SPRN_LPCR);
742 	system_registers.hfscr = mfspr(SPRN_HFSCR);
743 	system_registers.fscr = mfspr(SPRN_FSCR);
744 
745 	pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
746 		cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
747 }
748 
749 static int __init disabled_on_cmdline(void)
750 {
751 	unsigned long root, chosen;
752 	const char *p;
753 
754 	root = of_get_flat_dt_root();
755 	chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
756 	if (chosen == -FDT_ERR_NOTFOUND)
757 		return false;
758 
759 	p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
760 	if (!p)
761 		return false;
762 
763 	if (strstr(p, "dt_cpu_ftrs=off"))
764 		return true;
765 
766 	return false;
767 }
768 
769 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
770 					int depth, void *data)
771 {
772 	if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
773 	    && of_get_flat_dt_prop(node, "isa", NULL))
774 		return 1;
775 
776 	return 0;
777 }
778 
779 bool __init dt_cpu_ftrs_in_use(void)
780 {
781 	return using_dt_cpu_ftrs;
782 }
783 
784 bool __init dt_cpu_ftrs_init(void *fdt)
785 {
786 	using_dt_cpu_ftrs = false;
787 
788 	/* Setup and verify the FDT, if it fails we just bail */
789 	if (!early_init_dt_verify(fdt))
790 		return false;
791 
792 	if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
793 		return false;
794 
795 	if (disabled_on_cmdline())
796 		return false;
797 
798 	cpufeatures_setup_cpu();
799 
800 	using_dt_cpu_ftrs = true;
801 	return true;
802 }
803 
804 static int nr_dt_cpu_features;
805 static struct dt_cpu_feature *dt_cpu_features;
806 
807 static int __init process_cpufeatures_node(unsigned long node,
808 					  const char *uname, int i)
809 {
810 	const __be32 *prop;
811 	struct dt_cpu_feature *f;
812 	int len;
813 
814 	f = &dt_cpu_features[i];
815 	memset(f, 0, sizeof(struct dt_cpu_feature));
816 
817 	f->node = node;
818 
819 	f->name = uname;
820 
821 	prop = of_get_flat_dt_prop(node, "isa", &len);
822 	if (!prop) {
823 		pr_warn("%s: missing isa property\n", uname);
824 		return 0;
825 	}
826 	f->isa = be32_to_cpup(prop);
827 
828 	prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
829 	if (!prop) {
830 		pr_warn("%s: missing usable-privilege property", uname);
831 		return 0;
832 	}
833 	f->usable_privilege = be32_to_cpup(prop);
834 
835 	prop = of_get_flat_dt_prop(node, "hv-support", &len);
836 	if (prop)
837 		f->hv_support = be32_to_cpup(prop);
838 	else
839 		f->hv_support = HV_SUPPORT_NONE;
840 
841 	prop = of_get_flat_dt_prop(node, "os-support", &len);
842 	if (prop)
843 		f->os_support = be32_to_cpup(prop);
844 	else
845 		f->os_support = OS_SUPPORT_NONE;
846 
847 	prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
848 	if (prop)
849 		f->hfscr_bit_nr = be32_to_cpup(prop);
850 	else
851 		f->hfscr_bit_nr = -1;
852 	prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
853 	if (prop)
854 		f->fscr_bit_nr = be32_to_cpup(prop);
855 	else
856 		f->fscr_bit_nr = -1;
857 	prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
858 	if (prop)
859 		f->hwcap_bit_nr = be32_to_cpup(prop);
860 	else
861 		f->hwcap_bit_nr = -1;
862 
863 	if (f->usable_privilege & USABLE_HV) {
864 		if (!(mfmsr() & MSR_HV)) {
865 			pr_warn("%s: HV feature passed to guest\n", uname);
866 			return 0;
867 		}
868 
869 		if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
870 			pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
871 			return 0;
872 		}
873 
874 		if (f->hv_support == HV_SUPPORT_HFSCR) {
875 			if (f->hfscr_bit_nr == -1) {
876 				pr_warn("%s: missing hfscr_bit_nr\n", uname);
877 				return 0;
878 			}
879 		}
880 	} else {
881 		if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
882 			pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
883 			return 0;
884 		}
885 	}
886 
887 	if (f->usable_privilege & USABLE_OS) {
888 		if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
889 			pr_warn("%s: unwanted fscr_bit_nr\n", uname);
890 			return 0;
891 		}
892 
893 		if (f->os_support == OS_SUPPORT_FSCR) {
894 			if (f->fscr_bit_nr == -1) {
895 				pr_warn("%s: missing fscr_bit_nr\n", uname);
896 				return 0;
897 			}
898 		}
899 	} else {
900 		if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
901 			pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
902 			return 0;
903 		}
904 	}
905 
906 	if (!(f->usable_privilege & USABLE_PR)) {
907 		if (f->hwcap_bit_nr != -1) {
908 			pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
909 			return 0;
910 		}
911 	}
912 
913 	/* Do all the independent features in the first pass */
914 	if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
915 		if (cpufeatures_process_feature(f))
916 			f->enabled = 1;
917 		else
918 			f->disabled = 1;
919 	}
920 
921 	return 0;
922 }
923 
924 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
925 {
926 	const __be32 *prop;
927 	int len;
928 	int nr_deps;
929 	int i;
930 
931 	if (f->enabled || f->disabled)
932 		return;
933 
934 	prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
935 	if (!prop) {
936 		pr_warn("%s: missing dependencies property", f->name);
937 		return;
938 	}
939 
940 	nr_deps = len / sizeof(int);
941 
942 	for (i = 0; i < nr_deps; i++) {
943 		unsigned long phandle = be32_to_cpu(prop[i]);
944 		int j;
945 
946 		for (j = 0; j < nr_dt_cpu_features; j++) {
947 			struct dt_cpu_feature *d = &dt_cpu_features[j];
948 
949 			if (of_get_flat_dt_phandle(d->node) == phandle) {
950 				cpufeatures_deps_enable(d);
951 				if (d->disabled) {
952 					f->disabled = 1;
953 					return;
954 				}
955 			}
956 		}
957 	}
958 
959 	if (cpufeatures_process_feature(f))
960 		f->enabled = 1;
961 	else
962 		f->disabled = 1;
963 }
964 
965 static int __init scan_cpufeatures_subnodes(unsigned long node,
966 					  const char *uname,
967 					  void *data)
968 {
969 	int *count = data;
970 
971 	process_cpufeatures_node(node, uname, *count);
972 
973 	(*count)++;
974 
975 	return 0;
976 }
977 
978 static int __init count_cpufeatures_subnodes(unsigned long node,
979 					  const char *uname,
980 					  void *data)
981 {
982 	int *count = data;
983 
984 	(*count)++;
985 
986 	return 0;
987 }
988 
989 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
990 					    *uname, int depth, void *data)
991 {
992 	const __be32 *prop;
993 	int count, i;
994 	u32 isa;
995 
996 	/* We are scanning "ibm,powerpc-cpu-features" nodes only */
997 	if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
998 		return 0;
999 
1000 	prop = of_get_flat_dt_prop(node, "isa", NULL);
1001 	if (!prop)
1002 		/* We checked before, "can't happen" */
1003 		return 0;
1004 
1005 	isa = be32_to_cpup(prop);
1006 
1007 	/* Count and allocate space for cpu features */
1008 	of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1009 						&nr_dt_cpu_features);
1010 	dt_cpu_features = __va(
1011 		memblock_alloc(sizeof(struct dt_cpu_feature)*
1012 				nr_dt_cpu_features, PAGE_SIZE));
1013 
1014 	cpufeatures_setup_start(isa);
1015 
1016 	/* Scan nodes into dt_cpu_features and enable those without deps  */
1017 	count = 0;
1018 	of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1019 
1020 	/* Recursive enable remaining features with dependencies */
1021 	for (i = 0; i < nr_dt_cpu_features; i++) {
1022 		struct dt_cpu_feature *f = &dt_cpu_features[i];
1023 
1024 		cpufeatures_deps_enable(f);
1025 	}
1026 
1027 	prop = of_get_flat_dt_prop(node, "display-name", NULL);
1028 	if (prop && strlen((char *)prop) != 0) {
1029 		strlcpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1030 		cur_cpu_spec->cpu_name = dt_cpu_name;
1031 	}
1032 
1033 	cpufeatures_setup_finished();
1034 
1035 	memblock_free(__pa(dt_cpu_features),
1036 			sizeof(struct dt_cpu_feature)*nr_dt_cpu_features);
1037 
1038 	return 0;
1039 }
1040 
1041 void __init dt_cpu_ftrs_scan(void)
1042 {
1043 	if (!using_dt_cpu_ftrs)
1044 		return;
1045 
1046 	of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1047 }
1048