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/of_fdt.h>
14 #include <linux/printk.h>
15 #include <linux/sched.h>
16 #include <linux/string.h>
17 #include <linux/threads.h>
18
19 #include <asm/cputable.h>
20 #include <asm/dt_cpu_ftrs.h>
21 #include <asm/mce.h>
22 #include <asm/mmu.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 hfscr;
72 u64 fscr;
73 u64 pcr;
74 } system_registers;
75
76 static void (*init_pmu_registers)(void);
77
__restore_cpu_cpufeatures(void)78 static void __restore_cpu_cpufeatures(void)
79 {
80 mtspr(SPRN_LPCR, system_registers.lpcr);
81 if (hv_mode) {
82 mtspr(SPRN_LPID, 0);
83 mtspr(SPRN_AMOR, ~0);
84 mtspr(SPRN_HFSCR, system_registers.hfscr);
85 mtspr(SPRN_PCR, system_registers.pcr);
86 }
87 mtspr(SPRN_FSCR, system_registers.fscr);
88
89 if (init_pmu_registers)
90 init_pmu_registers();
91 }
92
93 static char dt_cpu_name[64];
94
95 static struct cpu_spec __initdata base_cpu_spec = {
96 .cpu_name = NULL,
97 .cpu_features = CPU_FTRS_DT_CPU_BASE,
98 .cpu_user_features = COMMON_USER_BASE,
99 .cpu_user_features2 = COMMON_USER2_BASE,
100 .mmu_features = 0,
101 .icache_bsize = 32, /* minimum block size, fixed by */
102 .dcache_bsize = 32, /* cache info init. */
103 .num_pmcs = 0,
104 .pmc_type = PPC_PMC_DEFAULT,
105 .cpu_setup = NULL,
106 .cpu_restore = __restore_cpu_cpufeatures,
107 .machine_check_early = NULL,
108 .platform = NULL,
109 };
110
cpufeatures_setup_cpu(void)111 static void __init cpufeatures_setup_cpu(void)
112 {
113 set_cur_cpu_spec(&base_cpu_spec);
114
115 cur_cpu_spec->pvr_mask = -1;
116 cur_cpu_spec->pvr_value = mfspr(SPRN_PVR);
117
118 /* Initialize the base environment -- clear FSCR/HFSCR. */
119 hv_mode = !!(mfmsr() & MSR_HV);
120 if (hv_mode) {
121 cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
122 mtspr(SPRN_HFSCR, 0);
123 }
124 mtspr(SPRN_FSCR, 0);
125 mtspr(SPRN_PCR, PCR_MASK);
126
127 /*
128 * LPCR does not get cleared, to match behaviour with secondaries
129 * in __restore_cpu_cpufeatures. Once the idle code is fixed, this
130 * could clear LPCR too.
131 */
132 }
133
feat_try_enable_unknown(struct dt_cpu_feature * f)134 static int __init feat_try_enable_unknown(struct dt_cpu_feature *f)
135 {
136 if (f->hv_support == HV_SUPPORT_NONE) {
137 } else if (f->hv_support & HV_SUPPORT_HFSCR) {
138 u64 hfscr = mfspr(SPRN_HFSCR);
139 hfscr |= 1UL << f->hfscr_bit_nr;
140 mtspr(SPRN_HFSCR, hfscr);
141 } else {
142 /* Does not have a known recipe */
143 return 0;
144 }
145
146 if (f->os_support == OS_SUPPORT_NONE) {
147 } else if (f->os_support & OS_SUPPORT_FSCR) {
148 u64 fscr = mfspr(SPRN_FSCR);
149 fscr |= 1UL << f->fscr_bit_nr;
150 mtspr(SPRN_FSCR, fscr);
151 } else {
152 /* Does not have a known recipe */
153 return 0;
154 }
155
156 if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
157 uint32_t word = f->hwcap_bit_nr / 32;
158 uint32_t bit = f->hwcap_bit_nr % 32;
159
160 if (word == 0)
161 cur_cpu_spec->cpu_user_features |= 1U << bit;
162 else if (word == 1)
163 cur_cpu_spec->cpu_user_features2 |= 1U << bit;
164 else
165 pr_err("%s could not advertise to user (no hwcap bits)\n", f->name);
166 }
167
168 return 1;
169 }
170
feat_enable(struct dt_cpu_feature * f)171 static int __init feat_enable(struct dt_cpu_feature *f)
172 {
173 if (f->hv_support != HV_SUPPORT_NONE) {
174 if (f->hfscr_bit_nr != -1) {
175 u64 hfscr = mfspr(SPRN_HFSCR);
176 hfscr |= 1UL << f->hfscr_bit_nr;
177 mtspr(SPRN_HFSCR, hfscr);
178 }
179 }
180
181 if (f->os_support != OS_SUPPORT_NONE) {
182 if (f->fscr_bit_nr != -1) {
183 u64 fscr = mfspr(SPRN_FSCR);
184 fscr |= 1UL << f->fscr_bit_nr;
185 mtspr(SPRN_FSCR, fscr);
186 }
187 }
188
189 if ((f->usable_privilege & USABLE_PR) && (f->hwcap_bit_nr != -1)) {
190 uint32_t word = f->hwcap_bit_nr / 32;
191 uint32_t bit = f->hwcap_bit_nr % 32;
192
193 if (word == 0)
194 cur_cpu_spec->cpu_user_features |= 1U << bit;
195 else if (word == 1)
196 cur_cpu_spec->cpu_user_features2 |= 1U << bit;
197 else
198 pr_err("CPU feature: %s could not advertise to user (no hwcap bits)\n", f->name);
199 }
200
201 return 1;
202 }
203
feat_disable(struct dt_cpu_feature * f)204 static int __init feat_disable(struct dt_cpu_feature *f)
205 {
206 return 0;
207 }
208
feat_enable_hv(struct dt_cpu_feature * f)209 static int __init feat_enable_hv(struct dt_cpu_feature *f)
210 {
211 u64 lpcr;
212
213 if (!hv_mode) {
214 pr_err("CPU feature hypervisor present in device tree but HV mode not enabled in the CPU. Ignoring.\n");
215 return 0;
216 }
217
218 mtspr(SPRN_LPID, 0);
219 mtspr(SPRN_AMOR, ~0);
220
221 lpcr = mfspr(SPRN_LPCR);
222 lpcr &= ~LPCR_LPES0; /* HV external interrupts */
223 mtspr(SPRN_LPCR, lpcr);
224
225 cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
226
227 return 1;
228 }
229
feat_enable_le(struct dt_cpu_feature * f)230 static int __init feat_enable_le(struct dt_cpu_feature *f)
231 {
232 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_TRUE_LE;
233 return 1;
234 }
235
feat_enable_smt(struct dt_cpu_feature * f)236 static int __init feat_enable_smt(struct dt_cpu_feature *f)
237 {
238 cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
239 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_SMT;
240 return 1;
241 }
242
feat_enable_idle_nap(struct dt_cpu_feature * f)243 static int __init feat_enable_idle_nap(struct dt_cpu_feature *f)
244 {
245 u64 lpcr;
246
247 /* Set PECE wakeup modes for ISA 207 */
248 lpcr = mfspr(SPRN_LPCR);
249 lpcr |= LPCR_PECE0;
250 lpcr |= LPCR_PECE1;
251 lpcr |= LPCR_PECE2;
252 mtspr(SPRN_LPCR, lpcr);
253
254 return 1;
255 }
256
feat_enable_idle_stop(struct dt_cpu_feature * f)257 static int __init feat_enable_idle_stop(struct dt_cpu_feature *f)
258 {
259 u64 lpcr;
260
261 /* Set PECE wakeup modes for ISAv3.0B */
262 lpcr = mfspr(SPRN_LPCR);
263 lpcr |= LPCR_PECE0;
264 lpcr |= LPCR_PECE1;
265 lpcr |= LPCR_PECE2;
266 mtspr(SPRN_LPCR, lpcr);
267
268 return 1;
269 }
270
feat_enable_mmu_hash(struct dt_cpu_feature * f)271 static int __init feat_enable_mmu_hash(struct dt_cpu_feature *f)
272 {
273 u64 lpcr;
274
275 if (!IS_ENABLED(CONFIG_PPC_64S_HASH_MMU))
276 return 0;
277
278 lpcr = mfspr(SPRN_LPCR);
279 lpcr &= ~LPCR_ISL;
280
281 /* VRMASD */
282 lpcr |= LPCR_VPM0;
283 lpcr &= ~LPCR_VPM1;
284 lpcr |= 0x10UL << LPCR_VRMASD_SH; /* L=1 LP=00 */
285 mtspr(SPRN_LPCR, lpcr);
286
287 cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
288 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
289
290 return 1;
291 }
292
feat_enable_mmu_hash_v3(struct dt_cpu_feature * f)293 static int __init feat_enable_mmu_hash_v3(struct dt_cpu_feature *f)
294 {
295 u64 lpcr;
296
297 if (!IS_ENABLED(CONFIG_PPC_64S_HASH_MMU))
298 return 0;
299
300 lpcr = mfspr(SPRN_LPCR);
301 lpcr &= ~(LPCR_ISL | LPCR_UPRT | LPCR_HR);
302 mtspr(SPRN_LPCR, lpcr);
303
304 cur_cpu_spec->mmu_features |= MMU_FTRS_HASH_BASE;
305 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
306
307 return 1;
308 }
309
310
feat_enable_mmu_radix(struct dt_cpu_feature * f)311 static int __init feat_enable_mmu_radix(struct dt_cpu_feature *f)
312 {
313 if (!IS_ENABLED(CONFIG_PPC_RADIX_MMU))
314 return 0;
315
316 cur_cpu_spec->mmu_features |= MMU_FTR_KERNEL_RO;
317 cur_cpu_spec->mmu_features |= MMU_FTR_TYPE_RADIX;
318 cur_cpu_spec->mmu_features |= MMU_FTR_GTSE;
319 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_MMU;
320
321 return 1;
322 }
323
feat_enable_dscr(struct dt_cpu_feature * f)324 static int __init feat_enable_dscr(struct dt_cpu_feature *f)
325 {
326 u64 lpcr;
327
328 /*
329 * Linux relies on FSCR[DSCR] being clear, so that we can take the
330 * facility unavailable interrupt and track the task's usage of DSCR.
331 * See facility_unavailable_exception().
332 * Clear the bit here so that feat_enable() doesn't set it.
333 */
334 f->fscr_bit_nr = -1;
335
336 feat_enable(f);
337
338 lpcr = mfspr(SPRN_LPCR);
339 lpcr &= ~LPCR_DPFD;
340 lpcr |= (4UL << LPCR_DPFD_SH);
341 mtspr(SPRN_LPCR, lpcr);
342
343 return 1;
344 }
345
hfscr_pmu_enable(void)346 static void __init hfscr_pmu_enable(void)
347 {
348 u64 hfscr = mfspr(SPRN_HFSCR);
349 hfscr |= PPC_BIT(60);
350 mtspr(SPRN_HFSCR, hfscr);
351 }
352
init_pmu_power8(void)353 static void init_pmu_power8(void)
354 {
355 if (hv_mode) {
356 mtspr(SPRN_MMCRC, 0);
357 mtspr(SPRN_MMCRH, 0);
358 }
359
360 mtspr(SPRN_MMCRA, 0);
361 mtspr(SPRN_MMCR0, MMCR0_FC);
362 mtspr(SPRN_MMCR1, 0);
363 mtspr(SPRN_MMCR2, 0);
364 mtspr(SPRN_MMCRS, 0);
365 }
366
feat_enable_mce_power8(struct dt_cpu_feature * f)367 static int __init feat_enable_mce_power8(struct dt_cpu_feature *f)
368 {
369 cur_cpu_spec->platform = "power8";
370 cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p8;
371
372 return 1;
373 }
374
feat_enable_pmu_power8(struct dt_cpu_feature * f)375 static int __init feat_enable_pmu_power8(struct dt_cpu_feature *f)
376 {
377 hfscr_pmu_enable();
378
379 init_pmu_power8();
380 init_pmu_registers = init_pmu_power8;
381
382 cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
383 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
384 if (pvr_version_is(PVR_POWER8E))
385 cur_cpu_spec->cpu_features |= CPU_FTR_PMAO_BUG;
386
387 cur_cpu_spec->num_pmcs = 6;
388 cur_cpu_spec->pmc_type = PPC_PMC_IBM;
389
390 return 1;
391 }
392
init_pmu_power9(void)393 static void init_pmu_power9(void)
394 {
395 if (hv_mode)
396 mtspr(SPRN_MMCRC, 0);
397
398 mtspr(SPRN_MMCRA, 0);
399 mtspr(SPRN_MMCR0, MMCR0_FC);
400 mtspr(SPRN_MMCR1, 0);
401 mtspr(SPRN_MMCR2, 0);
402 }
403
feat_enable_mce_power9(struct dt_cpu_feature * f)404 static int __init feat_enable_mce_power9(struct dt_cpu_feature *f)
405 {
406 cur_cpu_spec->platform = "power9";
407 cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p9;
408
409 return 1;
410 }
411
feat_enable_pmu_power9(struct dt_cpu_feature * f)412 static int __init feat_enable_pmu_power9(struct dt_cpu_feature *f)
413 {
414 hfscr_pmu_enable();
415
416 init_pmu_power9();
417 init_pmu_registers = init_pmu_power9;
418
419 cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
420 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
421
422 cur_cpu_spec->num_pmcs = 6;
423 cur_cpu_spec->pmc_type = PPC_PMC_IBM;
424
425 return 1;
426 }
427
init_pmu_power10(void)428 static void init_pmu_power10(void)
429 {
430 init_pmu_power9();
431
432 mtspr(SPRN_MMCR3, 0);
433 mtspr(SPRN_MMCRA, MMCRA_BHRB_DISABLE);
434 mtspr(SPRN_MMCR0, MMCR0_FC | MMCR0_PMCCEXT);
435 }
436
feat_enable_pmu_power10(struct dt_cpu_feature * f)437 static int __init feat_enable_pmu_power10(struct dt_cpu_feature *f)
438 {
439 hfscr_pmu_enable();
440
441 init_pmu_power10();
442 init_pmu_registers = init_pmu_power10;
443
444 cur_cpu_spec->cpu_features |= CPU_FTR_MMCRA;
445 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_PSERIES_PERFMON_COMPAT;
446
447 cur_cpu_spec->num_pmcs = 6;
448 cur_cpu_spec->pmc_type = PPC_PMC_IBM;
449
450 return 1;
451 }
452
feat_enable_mce_power10(struct dt_cpu_feature * f)453 static int __init feat_enable_mce_power10(struct dt_cpu_feature *f)
454 {
455 cur_cpu_spec->platform = "power10";
456 cur_cpu_spec->machine_check_early = __machine_check_early_realmode_p10;
457
458 return 1;
459 }
460
feat_enable_tm(struct dt_cpu_feature * f)461 static int __init feat_enable_tm(struct dt_cpu_feature *f)
462 {
463 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
464 feat_enable(f);
465 cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NOSC;
466 return 1;
467 #endif
468 return 0;
469 }
470
feat_enable_fp(struct dt_cpu_feature * f)471 static int __init feat_enable_fp(struct dt_cpu_feature *f)
472 {
473 feat_enable(f);
474 cur_cpu_spec->cpu_features &= ~CPU_FTR_FPU_UNAVAILABLE;
475
476 return 1;
477 }
478
feat_enable_vector(struct dt_cpu_feature * f)479 static int __init feat_enable_vector(struct dt_cpu_feature *f)
480 {
481 #ifdef CONFIG_ALTIVEC
482 feat_enable(f);
483 cur_cpu_spec->cpu_features |= CPU_FTR_ALTIVEC;
484 cur_cpu_spec->cpu_features |= CPU_FTR_VMX_COPY;
485 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_ALTIVEC;
486
487 return 1;
488 #endif
489 return 0;
490 }
491
feat_enable_vsx(struct dt_cpu_feature * f)492 static int __init feat_enable_vsx(struct dt_cpu_feature *f)
493 {
494 #ifdef CONFIG_VSX
495 feat_enable(f);
496 cur_cpu_spec->cpu_features |= CPU_FTR_VSX;
497 cur_cpu_spec->cpu_user_features |= PPC_FEATURE_HAS_VSX;
498
499 return 1;
500 #endif
501 return 0;
502 }
503
feat_enable_purr(struct dt_cpu_feature * f)504 static int __init feat_enable_purr(struct dt_cpu_feature *f)
505 {
506 cur_cpu_spec->cpu_features |= CPU_FTR_PURR | CPU_FTR_SPURR;
507
508 return 1;
509 }
510
feat_enable_ebb(struct dt_cpu_feature * f)511 static int __init feat_enable_ebb(struct dt_cpu_feature *f)
512 {
513 /*
514 * PPC_FEATURE2_EBB is enabled in PMU init code because it has
515 * historically been related to the PMU facility. This may have
516 * to be decoupled if EBB becomes more generic. For now, follow
517 * existing convention.
518 */
519 f->hwcap_bit_nr = -1;
520 feat_enable(f);
521
522 return 1;
523 }
524
feat_enable_dbell(struct dt_cpu_feature * f)525 static int __init feat_enable_dbell(struct dt_cpu_feature *f)
526 {
527 u64 lpcr;
528
529 /* P9 has an HFSCR for privileged state */
530 feat_enable(f);
531
532 cur_cpu_spec->cpu_features |= CPU_FTR_DBELL;
533
534 lpcr = mfspr(SPRN_LPCR);
535 lpcr |= LPCR_PECEDH; /* hyp doorbell wakeup */
536 mtspr(SPRN_LPCR, lpcr);
537
538 return 1;
539 }
540
feat_enable_hvi(struct dt_cpu_feature * f)541 static int __init feat_enable_hvi(struct dt_cpu_feature *f)
542 {
543 u64 lpcr;
544
545 /*
546 * POWER9 XIVE interrupts including in OPAL XICS compatibility
547 * are always delivered as hypervisor virtualization interrupts (HVI)
548 * rather than EE.
549 *
550 * However LPES0 is not set here, in the chance that an EE does get
551 * delivered to the host somehow, the EE handler would not expect it
552 * to be delivered in LPES0 mode (e.g., using SRR[01]). This could
553 * happen if there is a bug in interrupt controller code, or IC is
554 * misconfigured in systemsim.
555 */
556
557 lpcr = mfspr(SPRN_LPCR);
558 lpcr |= LPCR_HVICE; /* enable hvi interrupts */
559 lpcr |= LPCR_HEIC; /* disable ee interrupts when MSR_HV */
560 lpcr |= LPCR_PECE_HVEE; /* hvi can wake from stop */
561 mtspr(SPRN_LPCR, lpcr);
562
563 return 1;
564 }
565
feat_enable_large_ci(struct dt_cpu_feature * f)566 static int __init feat_enable_large_ci(struct dt_cpu_feature *f)
567 {
568 cur_cpu_spec->mmu_features |= MMU_FTR_CI_LARGE_PAGE;
569
570 return 1;
571 }
572
feat_enable_mma(struct dt_cpu_feature * f)573 static int __init feat_enable_mma(struct dt_cpu_feature *f)
574 {
575 u64 pcr;
576
577 feat_enable(f);
578 pcr = mfspr(SPRN_PCR);
579 pcr &= ~PCR_MMA_DIS;
580 mtspr(SPRN_PCR, pcr);
581
582 return 1;
583 }
584
585 struct dt_cpu_feature_match {
586 const char *name;
587 int (*enable)(struct dt_cpu_feature *f);
588 u64 cpu_ftr_bit_mask;
589 };
590
591 static struct dt_cpu_feature_match __initdata
592 dt_cpu_feature_match_table[] = {
593 {"hypervisor", feat_enable_hv, 0},
594 {"big-endian", feat_enable, 0},
595 {"little-endian", feat_enable_le, CPU_FTR_REAL_LE},
596 {"smt", feat_enable_smt, 0},
597 {"interrupt-facilities", feat_enable, 0},
598 {"system-call-vectored", feat_enable, 0},
599 {"timer-facilities", feat_enable, 0},
600 {"timer-facilities-v3", feat_enable, 0},
601 {"debug-facilities", feat_enable, 0},
602 {"come-from-address-register", feat_enable, CPU_FTR_CFAR},
603 {"branch-tracing", feat_enable, 0},
604 {"floating-point", feat_enable_fp, 0},
605 {"vector", feat_enable_vector, 0},
606 {"vector-scalar", feat_enable_vsx, 0},
607 {"vector-scalar-v3", feat_enable, 0},
608 {"decimal-floating-point", feat_enable, 0},
609 {"decimal-integer", feat_enable, 0},
610 {"quadword-load-store", feat_enable, 0},
611 {"vector-crypto", feat_enable, 0},
612 {"mmu-hash", feat_enable_mmu_hash, 0},
613 {"mmu-radix", feat_enable_mmu_radix, 0},
614 {"mmu-hash-v3", feat_enable_mmu_hash_v3, 0},
615 {"virtual-page-class-key-protection", feat_enable, 0},
616 {"transactional-memory", feat_enable_tm, CPU_FTR_TM},
617 {"transactional-memory-v3", feat_enable_tm, 0},
618 {"tm-suspend-hypervisor-assist", feat_enable, CPU_FTR_P9_TM_HV_ASSIST},
619 {"tm-suspend-xer-so-bug", feat_enable, CPU_FTR_P9_TM_XER_SO_BUG},
620 {"idle-nap", feat_enable_idle_nap, 0},
621 /* alignment-interrupt-dsisr ignored */
622 {"idle-stop", feat_enable_idle_stop, 0},
623 {"machine-check-power8", feat_enable_mce_power8, 0},
624 {"performance-monitor-power8", feat_enable_pmu_power8, 0},
625 {"data-stream-control-register", feat_enable_dscr, CPU_FTR_DSCR},
626 {"event-based-branch", feat_enable_ebb, 0},
627 {"target-address-register", feat_enable, 0},
628 {"branch-history-rolling-buffer", feat_enable, 0},
629 {"control-register", feat_enable, CPU_FTR_CTRL},
630 {"processor-control-facility", feat_enable_dbell, CPU_FTR_DBELL},
631 {"processor-control-facility-v3", feat_enable_dbell, CPU_FTR_DBELL},
632 {"processor-utilization-of-resources-register", feat_enable_purr, 0},
633 {"no-execute", feat_enable, 0},
634 {"strong-access-ordering", feat_enable, CPU_FTR_SAO},
635 {"cache-inhibited-large-page", feat_enable_large_ci, 0},
636 {"coprocessor-icswx", feat_enable, 0},
637 {"hypervisor-virtualization-interrupt", feat_enable_hvi, 0},
638 {"program-priority-register", feat_enable, CPU_FTR_HAS_PPR},
639 {"wait", feat_enable, 0},
640 {"atomic-memory-operations", feat_enable, 0},
641 {"branch-v3", feat_enable, 0},
642 {"copy-paste", feat_enable, 0},
643 {"decimal-floating-point-v3", feat_enable, 0},
644 {"decimal-integer-v3", feat_enable, 0},
645 {"fixed-point-v3", feat_enable, 0},
646 {"floating-point-v3", feat_enable, 0},
647 {"group-start-register", feat_enable, 0},
648 {"pc-relative-addressing", feat_enable, 0},
649 {"machine-check-power9", feat_enable_mce_power9, 0},
650 {"machine-check-power10", feat_enable_mce_power10, 0},
651 {"performance-monitor-power9", feat_enable_pmu_power9, 0},
652 {"performance-monitor-power10", feat_enable_pmu_power10, 0},
653 {"event-based-branch-v3", feat_enable, 0},
654 {"random-number-generator", feat_enable, 0},
655 {"system-call-vectored", feat_disable, 0},
656 {"trace-interrupt-v3", feat_enable, 0},
657 {"vector-v3", feat_enable, 0},
658 {"vector-binary128", feat_enable, 0},
659 {"vector-binary16", feat_enable, 0},
660 {"wait-v3", feat_enable, 0},
661 {"prefix-instructions", feat_enable, 0},
662 {"matrix-multiply-assist", feat_enable_mma, 0},
663 {"debug-facilities-v31", feat_enable, CPU_FTR_DAWR1},
664 };
665
666 static bool __initdata using_dt_cpu_ftrs;
667 static bool __initdata enable_unknown = true;
668
dt_cpu_ftrs_parse(char * str)669 static int __init dt_cpu_ftrs_parse(char *str)
670 {
671 if (!str)
672 return 0;
673
674 if (!strcmp(str, "off"))
675 using_dt_cpu_ftrs = false;
676 else if (!strcmp(str, "known"))
677 enable_unknown = false;
678 else
679 return 1;
680
681 return 0;
682 }
683 early_param("dt_cpu_ftrs", dt_cpu_ftrs_parse);
684
cpufeatures_setup_start(u32 isa)685 static void __init cpufeatures_setup_start(u32 isa)
686 {
687 pr_info("setup for ISA %d\n", isa);
688
689 if (isa >= ISA_V3_0B) {
690 cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_300;
691 cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_00;
692 }
693
694 if (isa >= ISA_V3_1) {
695 cur_cpu_spec->cpu_features |= CPU_FTR_ARCH_31;
696 cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_ARCH_3_1;
697 }
698 }
699
cpufeatures_process_feature(struct dt_cpu_feature * f)700 static bool __init cpufeatures_process_feature(struct dt_cpu_feature *f)
701 {
702 const struct dt_cpu_feature_match *m;
703 bool known = false;
704 int i;
705
706 for (i = 0; i < ARRAY_SIZE(dt_cpu_feature_match_table); i++) {
707 m = &dt_cpu_feature_match_table[i];
708 if (!strcmp(f->name, m->name)) {
709 known = true;
710 if (m->enable(f)) {
711 cur_cpu_spec->cpu_features |= m->cpu_ftr_bit_mask;
712 break;
713 }
714
715 pr_info("not enabling: %s (disabled or unsupported by kernel)\n",
716 f->name);
717 return false;
718 }
719 }
720
721 if (!known && (!enable_unknown || !feat_try_enable_unknown(f))) {
722 pr_info("not enabling: %s (unknown and unsupported by kernel)\n",
723 f->name);
724 return false;
725 }
726
727 if (known)
728 pr_debug("enabling: %s\n", f->name);
729 else
730 pr_debug("enabling: %s (unknown)\n", f->name);
731
732 return true;
733 }
734
735 /*
736 * Handle POWER9 broadcast tlbie invalidation issue using
737 * cpu feature flag.
738 */
update_tlbie_feature_flag(unsigned long pvr)739 static __init void update_tlbie_feature_flag(unsigned long pvr)
740 {
741 if (PVR_VER(pvr) == PVR_POWER9) {
742 /*
743 * Set the tlbie feature flag for anything below
744 * Nimbus DD 2.3 and Cumulus DD 1.3
745 */
746 if ((pvr & 0xe000) == 0) {
747 /* Nimbus */
748 if ((pvr & 0xfff) < 0x203)
749 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
750 } else if ((pvr & 0xc000) == 0) {
751 /* Cumulus */
752 if ((pvr & 0xfff) < 0x103)
753 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
754 } else {
755 WARN_ONCE(1, "Unknown PVR");
756 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_STQ_BUG;
757 }
758
759 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TLBIE_ERAT_BUG;
760 }
761 }
762
cpufeatures_cpu_quirks(void)763 static __init void cpufeatures_cpu_quirks(void)
764 {
765 unsigned long version = mfspr(SPRN_PVR);
766
767 /*
768 * Not all quirks can be derived from the cpufeatures device tree.
769 */
770 if ((version & 0xffffefff) == 0x004e0200) {
771 /* DD2.0 has no feature flag */
772 cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
773 cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
774 } else if ((version & 0xffffefff) == 0x004e0201) {
775 cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
776 cur_cpu_spec->cpu_features |= CPU_FTR_P9_RADIX_PREFETCH_BUG;
777 cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
778 } else if ((version & 0xffffefff) == 0x004e0202) {
779 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
780 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
781 cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
782 cur_cpu_spec->cpu_features &= ~(CPU_FTR_DAWR);
783 } else if ((version & 0xffffefff) == 0x004e0203) {
784 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_HV_ASSIST;
785 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TM_XER_SO_BUG;
786 cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
787 } else if ((version & 0xffff0000) == 0x004e0000) {
788 /* DD2.1 and up have DD2_1 */
789 cur_cpu_spec->cpu_features |= CPU_FTR_POWER9_DD2_1;
790 }
791
792 if ((version & 0xffff0000) == 0x004e0000) {
793 cur_cpu_spec->cpu_features |= CPU_FTR_P9_TIDR;
794 }
795
796 update_tlbie_feature_flag(version);
797 }
798
cpufeatures_setup_finished(void)799 static void __init cpufeatures_setup_finished(void)
800 {
801 cpufeatures_cpu_quirks();
802
803 if (hv_mode && !(cur_cpu_spec->cpu_features & CPU_FTR_HVMODE)) {
804 pr_err("hypervisor not present in device tree but HV mode is enabled in the CPU. Enabling.\n");
805 cur_cpu_spec->cpu_features |= CPU_FTR_HVMODE;
806 }
807
808 /* Make sure powerpc_base_platform is non-NULL */
809 powerpc_base_platform = cur_cpu_spec->platform;
810
811 system_registers.lpcr = mfspr(SPRN_LPCR);
812 system_registers.hfscr = mfspr(SPRN_HFSCR);
813 system_registers.fscr = mfspr(SPRN_FSCR);
814 system_registers.pcr = mfspr(SPRN_PCR);
815
816 pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n",
817 cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features);
818 }
819
disabled_on_cmdline(void)820 static int __init disabled_on_cmdline(void)
821 {
822 unsigned long root, chosen;
823 const char *p;
824
825 root = of_get_flat_dt_root();
826 chosen = of_get_flat_dt_subnode_by_name(root, "chosen");
827 if (chosen == -FDT_ERR_NOTFOUND)
828 return false;
829
830 p = of_get_flat_dt_prop(chosen, "bootargs", NULL);
831 if (!p)
832 return false;
833
834 if (strstr(p, "dt_cpu_ftrs=off"))
835 return true;
836
837 return false;
838 }
839
fdt_find_cpu_features(unsigned long node,const char * uname,int depth,void * data)840 static int __init fdt_find_cpu_features(unsigned long node, const char *uname,
841 int depth, void *data)
842 {
843 if (of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features")
844 && of_get_flat_dt_prop(node, "isa", NULL))
845 return 1;
846
847 return 0;
848 }
849
dt_cpu_ftrs_in_use(void)850 bool __init dt_cpu_ftrs_in_use(void)
851 {
852 return using_dt_cpu_ftrs;
853 }
854
dt_cpu_ftrs_init(void * fdt)855 bool __init dt_cpu_ftrs_init(void *fdt)
856 {
857 using_dt_cpu_ftrs = false;
858
859 /* Setup and verify the FDT, if it fails we just bail */
860 if (!early_init_dt_verify(fdt))
861 return false;
862
863 if (!of_scan_flat_dt(fdt_find_cpu_features, NULL))
864 return false;
865
866 if (disabled_on_cmdline())
867 return false;
868
869 cpufeatures_setup_cpu();
870
871 using_dt_cpu_ftrs = true;
872 return true;
873 }
874
875 static int nr_dt_cpu_features;
876 static struct dt_cpu_feature *dt_cpu_features;
877
process_cpufeatures_node(unsigned long node,const char * uname,int i)878 static int __init process_cpufeatures_node(unsigned long node,
879 const char *uname, int i)
880 {
881 const __be32 *prop;
882 struct dt_cpu_feature *f;
883 int len;
884
885 f = &dt_cpu_features[i];
886
887 f->node = node;
888
889 f->name = uname;
890
891 prop = of_get_flat_dt_prop(node, "isa", &len);
892 if (!prop) {
893 pr_warn("%s: missing isa property\n", uname);
894 return 0;
895 }
896 f->isa = be32_to_cpup(prop);
897
898 prop = of_get_flat_dt_prop(node, "usable-privilege", &len);
899 if (!prop) {
900 pr_warn("%s: missing usable-privilege property", uname);
901 return 0;
902 }
903 f->usable_privilege = be32_to_cpup(prop);
904
905 prop = of_get_flat_dt_prop(node, "hv-support", &len);
906 if (prop)
907 f->hv_support = be32_to_cpup(prop);
908 else
909 f->hv_support = HV_SUPPORT_NONE;
910
911 prop = of_get_flat_dt_prop(node, "os-support", &len);
912 if (prop)
913 f->os_support = be32_to_cpup(prop);
914 else
915 f->os_support = OS_SUPPORT_NONE;
916
917 prop = of_get_flat_dt_prop(node, "hfscr-bit-nr", &len);
918 if (prop)
919 f->hfscr_bit_nr = be32_to_cpup(prop);
920 else
921 f->hfscr_bit_nr = -1;
922 prop = of_get_flat_dt_prop(node, "fscr-bit-nr", &len);
923 if (prop)
924 f->fscr_bit_nr = be32_to_cpup(prop);
925 else
926 f->fscr_bit_nr = -1;
927 prop = of_get_flat_dt_prop(node, "hwcap-bit-nr", &len);
928 if (prop)
929 f->hwcap_bit_nr = be32_to_cpup(prop);
930 else
931 f->hwcap_bit_nr = -1;
932
933 if (f->usable_privilege & USABLE_HV) {
934 if (!(mfmsr() & MSR_HV)) {
935 pr_warn("%s: HV feature passed to guest\n", uname);
936 return 0;
937 }
938
939 if (f->hv_support == HV_SUPPORT_NONE && f->hfscr_bit_nr != -1) {
940 pr_warn("%s: unwanted hfscr_bit_nr\n", uname);
941 return 0;
942 }
943
944 if (f->hv_support == HV_SUPPORT_HFSCR) {
945 if (f->hfscr_bit_nr == -1) {
946 pr_warn("%s: missing hfscr_bit_nr\n", uname);
947 return 0;
948 }
949 }
950 } else {
951 if (f->hv_support != HV_SUPPORT_NONE || f->hfscr_bit_nr != -1) {
952 pr_warn("%s: unwanted hv_support/hfscr_bit_nr\n", uname);
953 return 0;
954 }
955 }
956
957 if (f->usable_privilege & USABLE_OS) {
958 if (f->os_support == OS_SUPPORT_NONE && f->fscr_bit_nr != -1) {
959 pr_warn("%s: unwanted fscr_bit_nr\n", uname);
960 return 0;
961 }
962
963 if (f->os_support == OS_SUPPORT_FSCR) {
964 if (f->fscr_bit_nr == -1) {
965 pr_warn("%s: missing fscr_bit_nr\n", uname);
966 return 0;
967 }
968 }
969 } else {
970 if (f->os_support != OS_SUPPORT_NONE || f->fscr_bit_nr != -1) {
971 pr_warn("%s: unwanted os_support/fscr_bit_nr\n", uname);
972 return 0;
973 }
974 }
975
976 if (!(f->usable_privilege & USABLE_PR)) {
977 if (f->hwcap_bit_nr != -1) {
978 pr_warn("%s: unwanted hwcap_bit_nr\n", uname);
979 return 0;
980 }
981 }
982
983 /* Do all the independent features in the first pass */
984 if (!of_get_flat_dt_prop(node, "dependencies", &len)) {
985 if (cpufeatures_process_feature(f))
986 f->enabled = 1;
987 else
988 f->disabled = 1;
989 }
990
991 return 0;
992 }
993
cpufeatures_deps_enable(struct dt_cpu_feature * f)994 static void __init cpufeatures_deps_enable(struct dt_cpu_feature *f)
995 {
996 const __be32 *prop;
997 int len;
998 int nr_deps;
999 int i;
1000
1001 if (f->enabled || f->disabled)
1002 return;
1003
1004 prop = of_get_flat_dt_prop(f->node, "dependencies", &len);
1005 if (!prop) {
1006 pr_warn("%s: missing dependencies property", f->name);
1007 return;
1008 }
1009
1010 nr_deps = len / sizeof(int);
1011
1012 for (i = 0; i < nr_deps; i++) {
1013 unsigned long phandle = be32_to_cpu(prop[i]);
1014 int j;
1015
1016 for (j = 0; j < nr_dt_cpu_features; j++) {
1017 struct dt_cpu_feature *d = &dt_cpu_features[j];
1018
1019 if (of_get_flat_dt_phandle(d->node) == phandle) {
1020 cpufeatures_deps_enable(d);
1021 if (d->disabled) {
1022 f->disabled = 1;
1023 return;
1024 }
1025 }
1026 }
1027 }
1028
1029 if (cpufeatures_process_feature(f))
1030 f->enabled = 1;
1031 else
1032 f->disabled = 1;
1033 }
1034
scan_cpufeatures_subnodes(unsigned long node,const char * uname,void * data)1035 static int __init scan_cpufeatures_subnodes(unsigned long node,
1036 const char *uname,
1037 void *data)
1038 {
1039 int *count = data;
1040
1041 process_cpufeatures_node(node, uname, *count);
1042
1043 (*count)++;
1044
1045 return 0;
1046 }
1047
count_cpufeatures_subnodes(unsigned long node,const char * uname,void * data)1048 static int __init count_cpufeatures_subnodes(unsigned long node,
1049 const char *uname,
1050 void *data)
1051 {
1052 int *count = data;
1053
1054 (*count)++;
1055
1056 return 0;
1057 }
1058
dt_cpu_ftrs_scan_callback(unsigned long node,const char * uname,int depth,void * data)1059 static int __init dt_cpu_ftrs_scan_callback(unsigned long node, const char
1060 *uname, int depth, void *data)
1061 {
1062 const __be32 *prop;
1063 int count, i;
1064 u32 isa;
1065
1066 /* We are scanning "ibm,powerpc-cpu-features" nodes only */
1067 if (!of_flat_dt_is_compatible(node, "ibm,powerpc-cpu-features"))
1068 return 0;
1069
1070 prop = of_get_flat_dt_prop(node, "isa", NULL);
1071 if (!prop)
1072 /* We checked before, "can't happen" */
1073 return 0;
1074
1075 isa = be32_to_cpup(prop);
1076
1077 /* Count and allocate space for cpu features */
1078 of_scan_flat_dt_subnodes(node, count_cpufeatures_subnodes,
1079 &nr_dt_cpu_features);
1080 dt_cpu_features = memblock_alloc(sizeof(struct dt_cpu_feature) * nr_dt_cpu_features, PAGE_SIZE);
1081 if (!dt_cpu_features)
1082 panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
1083 __func__,
1084 sizeof(struct dt_cpu_feature) * nr_dt_cpu_features,
1085 PAGE_SIZE);
1086
1087 cpufeatures_setup_start(isa);
1088
1089 /* Scan nodes into dt_cpu_features and enable those without deps */
1090 count = 0;
1091 of_scan_flat_dt_subnodes(node, scan_cpufeatures_subnodes, &count);
1092
1093 /* Recursive enable remaining features with dependencies */
1094 for (i = 0; i < nr_dt_cpu_features; i++) {
1095 struct dt_cpu_feature *f = &dt_cpu_features[i];
1096
1097 cpufeatures_deps_enable(f);
1098 }
1099
1100 prop = of_get_flat_dt_prop(node, "display-name", NULL);
1101 if (prop && strlen((char *)prop) != 0) {
1102 strscpy(dt_cpu_name, (char *)prop, sizeof(dt_cpu_name));
1103 cur_cpu_spec->cpu_name = dt_cpu_name;
1104 }
1105
1106 cpufeatures_setup_finished();
1107
1108 memblock_free(dt_cpu_features,
1109 sizeof(struct dt_cpu_feature) * nr_dt_cpu_features);
1110
1111 return 0;
1112 }
1113
dt_cpu_ftrs_scan(void)1114 void __init dt_cpu_ftrs_scan(void)
1115 {
1116 if (!using_dt_cpu_ftrs)
1117 return;
1118
1119 of_scan_flat_dt(dt_cpu_ftrs_scan_callback, NULL);
1120 }
1121