xref: /openbmc/linux/arch/powerpc/kernel/sysfs.c (revision f7777dcc)
1 #include <linux/device.h>
2 #include <linux/cpu.h>
3 #include <linux/smp.h>
4 #include <linux/percpu.h>
5 #include <linux/init.h>
6 #include <linux/sched.h>
7 #include <linux/export.h>
8 #include <linux/nodemask.h>
9 #include <linux/cpumask.h>
10 #include <linux/notifier.h>
11 
12 #include <asm/current.h>
13 #include <asm/processor.h>
14 #include <asm/cputable.h>
15 #include <asm/hvcall.h>
16 #include <asm/prom.h>
17 #include <asm/machdep.h>
18 #include <asm/smp.h>
19 #include <asm/pmc.h>
20 #include <asm/firmware.h>
21 
22 #include "cacheinfo.h"
23 
24 #ifdef CONFIG_PPC64
25 #include <asm/paca.h>
26 #include <asm/lppaca.h>
27 #endif
28 
29 static DEFINE_PER_CPU(struct cpu, cpu_devices);
30 
31 /*
32  * SMT snooze delay stuff, 64-bit only for now
33  */
34 
35 #ifdef CONFIG_PPC64
36 
37 /* Time in microseconds we delay before sleeping in the idle loop */
38 DEFINE_PER_CPU(long, smt_snooze_delay) = { 100 };
39 
40 static ssize_t store_smt_snooze_delay(struct device *dev,
41 				      struct device_attribute *attr,
42 				      const char *buf,
43 				      size_t count)
44 {
45 	struct cpu *cpu = container_of(dev, struct cpu, dev);
46 	ssize_t ret;
47 	long snooze;
48 
49 	ret = sscanf(buf, "%ld", &snooze);
50 	if (ret != 1)
51 		return -EINVAL;
52 
53 	per_cpu(smt_snooze_delay, cpu->dev.id) = snooze;
54 	update_smt_snooze_delay(cpu->dev.id, snooze);
55 
56 	return count;
57 }
58 
59 static ssize_t show_smt_snooze_delay(struct device *dev,
60 				     struct device_attribute *attr,
61 				     char *buf)
62 {
63 	struct cpu *cpu = container_of(dev, struct cpu, dev);
64 
65 	return sprintf(buf, "%ld\n", per_cpu(smt_snooze_delay, cpu->dev.id));
66 }
67 
68 static DEVICE_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
69 		   store_smt_snooze_delay);
70 
71 static int __init setup_smt_snooze_delay(char *str)
72 {
73 	unsigned int cpu;
74 	long snooze;
75 
76 	if (!cpu_has_feature(CPU_FTR_SMT))
77 		return 1;
78 
79 	snooze = simple_strtol(str, NULL, 10);
80 	for_each_possible_cpu(cpu)
81 		per_cpu(smt_snooze_delay, cpu) = snooze;
82 
83 	return 1;
84 }
85 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
86 
87 #endif /* CONFIG_PPC64 */
88 
89 /*
90  * Enabling PMCs will slow partition context switch times so we only do
91  * it the first time we write to the PMCs.
92  */
93 
94 static DEFINE_PER_CPU(char, pmcs_enabled);
95 
96 void ppc_enable_pmcs(void)
97 {
98 	ppc_set_pmu_inuse(1);
99 
100 	/* Only need to enable them once */
101 	if (__get_cpu_var(pmcs_enabled))
102 		return;
103 
104 	__get_cpu_var(pmcs_enabled) = 1;
105 
106 	if (ppc_md.enable_pmcs)
107 		ppc_md.enable_pmcs();
108 }
109 EXPORT_SYMBOL(ppc_enable_pmcs);
110 
111 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
112 static void read_##NAME(void *val) \
113 { \
114 	*(unsigned long *)val = mfspr(ADDRESS);	\
115 } \
116 static void write_##NAME(void *val) \
117 { \
118 	ppc_enable_pmcs(); \
119 	mtspr(ADDRESS, *(unsigned long *)val);	\
120 } \
121 static ssize_t show_##NAME(struct device *dev, \
122 			struct device_attribute *attr, \
123 			char *buf) \
124 { \
125 	struct cpu *cpu = container_of(dev, struct cpu, dev); \
126 	unsigned long val; \
127 	smp_call_function_single(cpu->dev.id, read_##NAME, &val, 1);	\
128 	return sprintf(buf, "%lx\n", val); \
129 } \
130 static ssize_t __used \
131 	store_##NAME(struct device *dev, struct device_attribute *attr, \
132 			const char *buf, size_t count) \
133 { \
134 	struct cpu *cpu = container_of(dev, struct cpu, dev); \
135 	unsigned long val; \
136 	int ret = sscanf(buf, "%lx", &val); \
137 	if (ret != 1) \
138 		return -EINVAL; \
139 	smp_call_function_single(cpu->dev.id, write_##NAME, &val, 1); \
140 	return count; \
141 }
142 
143 
144 /* Let's define all possible registers, we'll only hook up the ones
145  * that are implemented on the current processor
146  */
147 
148 #if defined(CONFIG_PPC64)
149 #define HAS_PPC_PMC_CLASSIC	1
150 #define HAS_PPC_PMC_IBM		1
151 #define HAS_PPC_PMC_PA6T	1
152 #elif defined(CONFIG_6xx)
153 #define HAS_PPC_PMC_CLASSIC	1
154 #define HAS_PPC_PMC_IBM		1
155 #define HAS_PPC_PMC_G4		1
156 #endif
157 
158 
159 #ifdef HAS_PPC_PMC_CLASSIC
160 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
161 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
162 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
163 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
164 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
165 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
166 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
167 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
168 
169 #ifdef HAS_PPC_PMC_G4
170 SYSFS_PMCSETUP(mmcr2, SPRN_MMCR2);
171 #endif
172 
173 #ifdef CONFIG_PPC64
174 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
175 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
176 
177 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
178 SYSFS_PMCSETUP(purr, SPRN_PURR);
179 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
180 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
181 SYSFS_PMCSETUP(pir, SPRN_PIR);
182 
183 /*
184   Lets only enable read for phyp resources and
185   enable write when needed with a separate function.
186   Lets be conservative and default to pseries.
187 */
188 static DEVICE_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
189 static DEVICE_ATTR(spurr, 0400, show_spurr, NULL);
190 static DEVICE_ATTR(dscr, 0600, show_dscr, store_dscr);
191 static DEVICE_ATTR(purr, 0400, show_purr, store_purr);
192 static DEVICE_ATTR(pir, 0400, show_pir, NULL);
193 
194 unsigned long dscr_default = 0;
195 EXPORT_SYMBOL(dscr_default);
196 
197 static void add_write_permission_dev_attr(struct device_attribute *attr)
198 {
199 	attr->attr.mode |= 0200;
200 }
201 
202 static ssize_t show_dscr_default(struct device *dev,
203 		struct device_attribute *attr, char *buf)
204 {
205 	return sprintf(buf, "%lx\n", dscr_default);
206 }
207 
208 static void update_dscr(void *dummy)
209 {
210 	if (!current->thread.dscr_inherit) {
211 		current->thread.dscr = dscr_default;
212 		mtspr(SPRN_DSCR, dscr_default);
213 	}
214 }
215 
216 static ssize_t __used store_dscr_default(struct device *dev,
217 		struct device_attribute *attr, const char *buf,
218 		size_t count)
219 {
220 	unsigned long val;
221 	int ret = 0;
222 
223 	ret = sscanf(buf, "%lx", &val);
224 	if (ret != 1)
225 		return -EINVAL;
226 	dscr_default = val;
227 
228 	on_each_cpu(update_dscr, NULL, 1);
229 
230 	return count;
231 }
232 
233 static DEVICE_ATTR(dscr_default, 0600,
234 		show_dscr_default, store_dscr_default);
235 
236 static void sysfs_create_dscr_default(void)
237 {
238 	int err = 0;
239 	if (cpu_has_feature(CPU_FTR_DSCR))
240 		err = device_create_file(cpu_subsys.dev_root, &dev_attr_dscr_default);
241 }
242 #endif /* CONFIG_PPC64 */
243 
244 #ifdef HAS_PPC_PMC_PA6T
245 SYSFS_PMCSETUP(pa6t_pmc0, SPRN_PA6T_PMC0);
246 SYSFS_PMCSETUP(pa6t_pmc1, SPRN_PA6T_PMC1);
247 SYSFS_PMCSETUP(pa6t_pmc2, SPRN_PA6T_PMC2);
248 SYSFS_PMCSETUP(pa6t_pmc3, SPRN_PA6T_PMC3);
249 SYSFS_PMCSETUP(pa6t_pmc4, SPRN_PA6T_PMC4);
250 SYSFS_PMCSETUP(pa6t_pmc5, SPRN_PA6T_PMC5);
251 #ifdef CONFIG_DEBUG_KERNEL
252 SYSFS_PMCSETUP(hid0, SPRN_HID0);
253 SYSFS_PMCSETUP(hid1, SPRN_HID1);
254 SYSFS_PMCSETUP(hid4, SPRN_HID4);
255 SYSFS_PMCSETUP(hid5, SPRN_HID5);
256 SYSFS_PMCSETUP(ima0, SPRN_PA6T_IMA0);
257 SYSFS_PMCSETUP(ima1, SPRN_PA6T_IMA1);
258 SYSFS_PMCSETUP(ima2, SPRN_PA6T_IMA2);
259 SYSFS_PMCSETUP(ima3, SPRN_PA6T_IMA3);
260 SYSFS_PMCSETUP(ima4, SPRN_PA6T_IMA4);
261 SYSFS_PMCSETUP(ima5, SPRN_PA6T_IMA5);
262 SYSFS_PMCSETUP(ima6, SPRN_PA6T_IMA6);
263 SYSFS_PMCSETUP(ima7, SPRN_PA6T_IMA7);
264 SYSFS_PMCSETUP(ima8, SPRN_PA6T_IMA8);
265 SYSFS_PMCSETUP(ima9, SPRN_PA6T_IMA9);
266 SYSFS_PMCSETUP(imaat, SPRN_PA6T_IMAAT);
267 SYSFS_PMCSETUP(btcr, SPRN_PA6T_BTCR);
268 SYSFS_PMCSETUP(pccr, SPRN_PA6T_PCCR);
269 SYSFS_PMCSETUP(rpccr, SPRN_PA6T_RPCCR);
270 SYSFS_PMCSETUP(der, SPRN_PA6T_DER);
271 SYSFS_PMCSETUP(mer, SPRN_PA6T_MER);
272 SYSFS_PMCSETUP(ber, SPRN_PA6T_BER);
273 SYSFS_PMCSETUP(ier, SPRN_PA6T_IER);
274 SYSFS_PMCSETUP(sier, SPRN_PA6T_SIER);
275 SYSFS_PMCSETUP(siar, SPRN_PA6T_SIAR);
276 SYSFS_PMCSETUP(tsr0, SPRN_PA6T_TSR0);
277 SYSFS_PMCSETUP(tsr1, SPRN_PA6T_TSR1);
278 SYSFS_PMCSETUP(tsr2, SPRN_PA6T_TSR2);
279 SYSFS_PMCSETUP(tsr3, SPRN_PA6T_TSR3);
280 #endif /* CONFIG_DEBUG_KERNEL */
281 #endif /* HAS_PPC_PMC_PA6T */
282 
283 #ifdef HAS_PPC_PMC_IBM
284 static struct device_attribute ibm_common_attrs[] = {
285 	__ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
286 	__ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
287 };
288 #endif /* HAS_PPC_PMC_G4 */
289 
290 #ifdef HAS_PPC_PMC_G4
291 static struct device_attribute g4_common_attrs[] = {
292 	__ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
293 	__ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
294 	__ATTR(mmcr2, 0600, show_mmcr2, store_mmcr2),
295 };
296 #endif /* HAS_PPC_PMC_G4 */
297 
298 static struct device_attribute classic_pmc_attrs[] = {
299 	__ATTR(pmc1, 0600, show_pmc1, store_pmc1),
300 	__ATTR(pmc2, 0600, show_pmc2, store_pmc2),
301 	__ATTR(pmc3, 0600, show_pmc3, store_pmc3),
302 	__ATTR(pmc4, 0600, show_pmc4, store_pmc4),
303 	__ATTR(pmc5, 0600, show_pmc5, store_pmc5),
304 	__ATTR(pmc6, 0600, show_pmc6, store_pmc6),
305 #ifdef CONFIG_PPC64
306 	__ATTR(pmc7, 0600, show_pmc7, store_pmc7),
307 	__ATTR(pmc8, 0600, show_pmc8, store_pmc8),
308 #endif
309 };
310 
311 #ifdef HAS_PPC_PMC_PA6T
312 static struct device_attribute pa6t_attrs[] = {
313 	__ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
314 	__ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
315 	__ATTR(pmc0, 0600, show_pa6t_pmc0, store_pa6t_pmc0),
316 	__ATTR(pmc1, 0600, show_pa6t_pmc1, store_pa6t_pmc1),
317 	__ATTR(pmc2, 0600, show_pa6t_pmc2, store_pa6t_pmc2),
318 	__ATTR(pmc3, 0600, show_pa6t_pmc3, store_pa6t_pmc3),
319 	__ATTR(pmc4, 0600, show_pa6t_pmc4, store_pa6t_pmc4),
320 	__ATTR(pmc5, 0600, show_pa6t_pmc5, store_pa6t_pmc5),
321 #ifdef CONFIG_DEBUG_KERNEL
322 	__ATTR(hid0, 0600, show_hid0, store_hid0),
323 	__ATTR(hid1, 0600, show_hid1, store_hid1),
324 	__ATTR(hid4, 0600, show_hid4, store_hid4),
325 	__ATTR(hid5, 0600, show_hid5, store_hid5),
326 	__ATTR(ima0, 0600, show_ima0, store_ima0),
327 	__ATTR(ima1, 0600, show_ima1, store_ima1),
328 	__ATTR(ima2, 0600, show_ima2, store_ima2),
329 	__ATTR(ima3, 0600, show_ima3, store_ima3),
330 	__ATTR(ima4, 0600, show_ima4, store_ima4),
331 	__ATTR(ima5, 0600, show_ima5, store_ima5),
332 	__ATTR(ima6, 0600, show_ima6, store_ima6),
333 	__ATTR(ima7, 0600, show_ima7, store_ima7),
334 	__ATTR(ima8, 0600, show_ima8, store_ima8),
335 	__ATTR(ima9, 0600, show_ima9, store_ima9),
336 	__ATTR(imaat, 0600, show_imaat, store_imaat),
337 	__ATTR(btcr, 0600, show_btcr, store_btcr),
338 	__ATTR(pccr, 0600, show_pccr, store_pccr),
339 	__ATTR(rpccr, 0600, show_rpccr, store_rpccr),
340 	__ATTR(der, 0600, show_der, store_der),
341 	__ATTR(mer, 0600, show_mer, store_mer),
342 	__ATTR(ber, 0600, show_ber, store_ber),
343 	__ATTR(ier, 0600, show_ier, store_ier),
344 	__ATTR(sier, 0600, show_sier, store_sier),
345 	__ATTR(siar, 0600, show_siar, store_siar),
346 	__ATTR(tsr0, 0600, show_tsr0, store_tsr0),
347 	__ATTR(tsr1, 0600, show_tsr1, store_tsr1),
348 	__ATTR(tsr2, 0600, show_tsr2, store_tsr2),
349 	__ATTR(tsr3, 0600, show_tsr3, store_tsr3),
350 #endif /* CONFIG_DEBUG_KERNEL */
351 };
352 #endif /* HAS_PPC_PMC_PA6T */
353 #endif /* HAS_PPC_PMC_CLASSIC */
354 
355 static void register_cpu_online(unsigned int cpu)
356 {
357 	struct cpu *c = &per_cpu(cpu_devices, cpu);
358 	struct device *s = &c->dev;
359 	struct device_attribute *attrs, *pmc_attrs;
360 	int i, nattrs;
361 
362 #ifdef CONFIG_PPC64
363 	if (cpu_has_feature(CPU_FTR_SMT))
364 		device_create_file(s, &dev_attr_smt_snooze_delay);
365 #endif
366 
367 	/* PMC stuff */
368 	switch (cur_cpu_spec->pmc_type) {
369 #ifdef HAS_PPC_PMC_IBM
370 	case PPC_PMC_IBM:
371 		attrs = ibm_common_attrs;
372 		nattrs = sizeof(ibm_common_attrs) / sizeof(struct device_attribute);
373 		pmc_attrs = classic_pmc_attrs;
374 		break;
375 #endif /* HAS_PPC_PMC_IBM */
376 #ifdef HAS_PPC_PMC_G4
377 	case PPC_PMC_G4:
378 		attrs = g4_common_attrs;
379 		nattrs = sizeof(g4_common_attrs) / sizeof(struct device_attribute);
380 		pmc_attrs = classic_pmc_attrs;
381 		break;
382 #endif /* HAS_PPC_PMC_G4 */
383 #ifdef HAS_PPC_PMC_PA6T
384 	case PPC_PMC_PA6T:
385 		/* PA Semi starts counting at PMC0 */
386 		attrs = pa6t_attrs;
387 		nattrs = sizeof(pa6t_attrs) / sizeof(struct device_attribute);
388 		pmc_attrs = NULL;
389 		break;
390 #endif /* HAS_PPC_PMC_PA6T */
391 	default:
392 		attrs = NULL;
393 		nattrs = 0;
394 		pmc_attrs = NULL;
395 	}
396 
397 	for (i = 0; i < nattrs; i++)
398 		device_create_file(s, &attrs[i]);
399 
400 	if (pmc_attrs)
401 		for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
402 			device_create_file(s, &pmc_attrs[i]);
403 
404 #ifdef CONFIG_PPC64
405 	if (cpu_has_feature(CPU_FTR_MMCRA))
406 		device_create_file(s, &dev_attr_mmcra);
407 
408 	if (cpu_has_feature(CPU_FTR_PURR)) {
409 		if (!firmware_has_feature(FW_FEATURE_LPAR))
410 			add_write_permission_dev_attr(&dev_attr_purr);
411 		device_create_file(s, &dev_attr_purr);
412 	}
413 
414 	if (cpu_has_feature(CPU_FTR_SPURR))
415 		device_create_file(s, &dev_attr_spurr);
416 
417 	if (cpu_has_feature(CPU_FTR_DSCR))
418 		device_create_file(s, &dev_attr_dscr);
419 
420 	if (cpu_has_feature(CPU_FTR_PPCAS_ARCH_V2))
421 		device_create_file(s, &dev_attr_pir);
422 #endif /* CONFIG_PPC64 */
423 
424 	cacheinfo_cpu_online(cpu);
425 }
426 
427 #ifdef CONFIG_HOTPLUG_CPU
428 static void unregister_cpu_online(unsigned int cpu)
429 {
430 	struct cpu *c = &per_cpu(cpu_devices, cpu);
431 	struct device *s = &c->dev;
432 	struct device_attribute *attrs, *pmc_attrs;
433 	int i, nattrs;
434 
435 	BUG_ON(!c->hotpluggable);
436 
437 #ifdef CONFIG_PPC64
438 	if (cpu_has_feature(CPU_FTR_SMT))
439 		device_remove_file(s, &dev_attr_smt_snooze_delay);
440 #endif
441 
442 	/* PMC stuff */
443 	switch (cur_cpu_spec->pmc_type) {
444 #ifdef HAS_PPC_PMC_IBM
445 	case PPC_PMC_IBM:
446 		attrs = ibm_common_attrs;
447 		nattrs = sizeof(ibm_common_attrs) / sizeof(struct device_attribute);
448 		pmc_attrs = classic_pmc_attrs;
449 		break;
450 #endif /* HAS_PPC_PMC_IBM */
451 #ifdef HAS_PPC_PMC_G4
452 	case PPC_PMC_G4:
453 		attrs = g4_common_attrs;
454 		nattrs = sizeof(g4_common_attrs) / sizeof(struct device_attribute);
455 		pmc_attrs = classic_pmc_attrs;
456 		break;
457 #endif /* HAS_PPC_PMC_G4 */
458 #ifdef HAS_PPC_PMC_PA6T
459 	case PPC_PMC_PA6T:
460 		/* PA Semi starts counting at PMC0 */
461 		attrs = pa6t_attrs;
462 		nattrs = sizeof(pa6t_attrs) / sizeof(struct device_attribute);
463 		pmc_attrs = NULL;
464 		break;
465 #endif /* HAS_PPC_PMC_PA6T */
466 	default:
467 		attrs = NULL;
468 		nattrs = 0;
469 		pmc_attrs = NULL;
470 	}
471 
472 	for (i = 0; i < nattrs; i++)
473 		device_remove_file(s, &attrs[i]);
474 
475 	if (pmc_attrs)
476 		for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
477 			device_remove_file(s, &pmc_attrs[i]);
478 
479 #ifdef CONFIG_PPC64
480 	if (cpu_has_feature(CPU_FTR_MMCRA))
481 		device_remove_file(s, &dev_attr_mmcra);
482 
483 	if (cpu_has_feature(CPU_FTR_PURR))
484 		device_remove_file(s, &dev_attr_purr);
485 
486 	if (cpu_has_feature(CPU_FTR_SPURR))
487 		device_remove_file(s, &dev_attr_spurr);
488 
489 	if (cpu_has_feature(CPU_FTR_DSCR))
490 		device_remove_file(s, &dev_attr_dscr);
491 
492 	if (cpu_has_feature(CPU_FTR_PPCAS_ARCH_V2))
493 		device_remove_file(s, &dev_attr_pir);
494 #endif /* CONFIG_PPC64 */
495 
496 	cacheinfo_cpu_offline(cpu);
497 }
498 
499 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
500 ssize_t arch_cpu_probe(const char *buf, size_t count)
501 {
502 	if (ppc_md.cpu_probe)
503 		return ppc_md.cpu_probe(buf, count);
504 
505 	return -EINVAL;
506 }
507 
508 ssize_t arch_cpu_release(const char *buf, size_t count)
509 {
510 	if (ppc_md.cpu_release)
511 		return ppc_md.cpu_release(buf, count);
512 
513 	return -EINVAL;
514 }
515 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
516 
517 #endif /* CONFIG_HOTPLUG_CPU */
518 
519 static int sysfs_cpu_notify(struct notifier_block *self,
520 				      unsigned long action, void *hcpu)
521 {
522 	unsigned int cpu = (unsigned int)(long)hcpu;
523 
524 	switch (action) {
525 	case CPU_ONLINE:
526 	case CPU_ONLINE_FROZEN:
527 		register_cpu_online(cpu);
528 		break;
529 #ifdef CONFIG_HOTPLUG_CPU
530 	case CPU_DEAD:
531 	case CPU_DEAD_FROZEN:
532 		unregister_cpu_online(cpu);
533 		break;
534 #endif
535 	}
536 	return NOTIFY_OK;
537 }
538 
539 static struct notifier_block sysfs_cpu_nb = {
540 	.notifier_call	= sysfs_cpu_notify,
541 };
542 
543 static DEFINE_MUTEX(cpu_mutex);
544 
545 int cpu_add_dev_attr(struct device_attribute *attr)
546 {
547 	int cpu;
548 
549 	mutex_lock(&cpu_mutex);
550 
551 	for_each_possible_cpu(cpu) {
552 		device_create_file(get_cpu_device(cpu), attr);
553 	}
554 
555 	mutex_unlock(&cpu_mutex);
556 	return 0;
557 }
558 EXPORT_SYMBOL_GPL(cpu_add_dev_attr);
559 
560 int cpu_add_dev_attr_group(struct attribute_group *attrs)
561 {
562 	int cpu;
563 	struct device *dev;
564 	int ret;
565 
566 	mutex_lock(&cpu_mutex);
567 
568 	for_each_possible_cpu(cpu) {
569 		dev = get_cpu_device(cpu);
570 		ret = sysfs_create_group(&dev->kobj, attrs);
571 		WARN_ON(ret != 0);
572 	}
573 
574 	mutex_unlock(&cpu_mutex);
575 	return 0;
576 }
577 EXPORT_SYMBOL_GPL(cpu_add_dev_attr_group);
578 
579 
580 void cpu_remove_dev_attr(struct device_attribute *attr)
581 {
582 	int cpu;
583 
584 	mutex_lock(&cpu_mutex);
585 
586 	for_each_possible_cpu(cpu) {
587 		device_remove_file(get_cpu_device(cpu), attr);
588 	}
589 
590 	mutex_unlock(&cpu_mutex);
591 }
592 EXPORT_SYMBOL_GPL(cpu_remove_dev_attr);
593 
594 void cpu_remove_dev_attr_group(struct attribute_group *attrs)
595 {
596 	int cpu;
597 	struct device *dev;
598 
599 	mutex_lock(&cpu_mutex);
600 
601 	for_each_possible_cpu(cpu) {
602 		dev = get_cpu_device(cpu);
603 		sysfs_remove_group(&dev->kobj, attrs);
604 	}
605 
606 	mutex_unlock(&cpu_mutex);
607 }
608 EXPORT_SYMBOL_GPL(cpu_remove_dev_attr_group);
609 
610 
611 /* NUMA stuff */
612 
613 #ifdef CONFIG_NUMA
614 static void register_nodes(void)
615 {
616 	int i;
617 
618 	for (i = 0; i < MAX_NUMNODES; i++)
619 		register_one_node(i);
620 }
621 
622 int sysfs_add_device_to_node(struct device *dev, int nid)
623 {
624 	struct node *node = node_devices[nid];
625 	return sysfs_create_link(&node->dev.kobj, &dev->kobj,
626 			kobject_name(&dev->kobj));
627 }
628 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
629 
630 void sysfs_remove_device_from_node(struct device *dev, int nid)
631 {
632 	struct node *node = node_devices[nid];
633 	sysfs_remove_link(&node->dev.kobj, kobject_name(&dev->kobj));
634 }
635 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
636 
637 #else
638 static void register_nodes(void)
639 {
640 	return;
641 }
642 
643 #endif
644 
645 /* Only valid if CPU is present. */
646 static ssize_t show_physical_id(struct device *dev,
647 				struct device_attribute *attr, char *buf)
648 {
649 	struct cpu *cpu = container_of(dev, struct cpu, dev);
650 
651 	return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->dev.id));
652 }
653 static DEVICE_ATTR(physical_id, 0444, show_physical_id, NULL);
654 
655 static int __init topology_init(void)
656 {
657 	int cpu;
658 
659 	register_nodes();
660 	register_cpu_notifier(&sysfs_cpu_nb);
661 
662 	for_each_possible_cpu(cpu) {
663 		struct cpu *c = &per_cpu(cpu_devices, cpu);
664 
665 		/*
666 		 * For now, we just see if the system supports making
667 		 * the RTAS calls for CPU hotplug.  But, there may be a
668 		 * more comprehensive way to do this for an individual
669 		 * CPU.  For instance, the boot cpu might never be valid
670 		 * for hotplugging.
671 		 */
672 		if (ppc_md.cpu_die)
673 			c->hotpluggable = 1;
674 
675 		if (cpu_online(cpu) || c->hotpluggable) {
676 			register_cpu(c, cpu);
677 
678 			device_create_file(&c->dev, &dev_attr_physical_id);
679 		}
680 
681 		if (cpu_online(cpu))
682 			register_cpu_online(cpu);
683 	}
684 #ifdef CONFIG_PPC64
685 	sysfs_create_dscr_default();
686 #endif /* CONFIG_PPC64 */
687 
688 	return 0;
689 }
690 subsys_initcall(topology_init);
691