xref: /linux/arch/powerpc/kernel/sysfs.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 #include <linux/sysdev.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/firmware.h>
16 #include <asm/hvcall.h>
17 #include <asm/prom.h>
18 #include <asm/machdep.h>
19 #include <asm/smp.h>
20 #include <asm/pmc.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 sys_device *dev,
41 				      struct sysdev_attribute *attr,
42 				      const char *buf,
43 				      size_t count)
44 {
45 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
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->sysdev.id) = snooze;
54 
55 	return count;
56 }
57 
58 static ssize_t show_smt_snooze_delay(struct sys_device *dev,
59 				     struct sysdev_attribute *attr,
60 				     char *buf)
61 {
62 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
63 
64 	return sprintf(buf, "%ld\n", per_cpu(smt_snooze_delay, cpu->sysdev.id));
65 }
66 
67 static SYSDEV_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
68 		   store_smt_snooze_delay);
69 
70 static int __init setup_smt_snooze_delay(char *str)
71 {
72 	unsigned int cpu;
73 	long snooze;
74 
75 	if (!cpu_has_feature(CPU_FTR_SMT))
76 		return 1;
77 
78 	snooze = simple_strtol(str, NULL, 10);
79 	for_each_possible_cpu(cpu)
80 		per_cpu(smt_snooze_delay, cpu) = snooze;
81 
82 	return 1;
83 }
84 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
85 
86 #endif /* CONFIG_PPC64 */
87 
88 /*
89  * Enabling PMCs will slow partition context switch times so we only do
90  * it the first time we write to the PMCs.
91  */
92 
93 static DEFINE_PER_CPU(char, pmcs_enabled);
94 
95 void ppc_enable_pmcs(void)
96 {
97 	ppc_set_pmu_inuse(1);
98 
99 	/* Only need to enable them once */
100 	if (__get_cpu_var(pmcs_enabled))
101 		return;
102 
103 	__get_cpu_var(pmcs_enabled) = 1;
104 
105 	if (ppc_md.enable_pmcs)
106 		ppc_md.enable_pmcs();
107 }
108 EXPORT_SYMBOL(ppc_enable_pmcs);
109 
110 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
111 static void read_##NAME(void *val) \
112 { \
113 	*(unsigned long *)val = mfspr(ADDRESS);	\
114 } \
115 static void write_##NAME(void *val) \
116 { \
117 	ppc_enable_pmcs(); \
118 	mtspr(ADDRESS, *(unsigned long *)val);	\
119 } \
120 static ssize_t show_##NAME(struct sys_device *dev, \
121 			struct sysdev_attribute *attr, \
122 			char *buf) \
123 { \
124 	struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
125 	unsigned long val; \
126 	smp_call_function_single(cpu->sysdev.id, read_##NAME, &val, 1);	\
127 	return sprintf(buf, "%lx\n", val); \
128 } \
129 static ssize_t __used \
130 	store_##NAME(struct sys_device *dev, struct sysdev_attribute *attr, \
131 			const char *buf, size_t count) \
132 { \
133 	struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
134 	unsigned long val; \
135 	int ret = sscanf(buf, "%lx", &val); \
136 	if (ret != 1) \
137 		return -EINVAL; \
138 	smp_call_function_single(cpu->sysdev.id, write_##NAME, &val, 1); \
139 	return count; \
140 }
141 
142 
143 /* Let's define all possible registers, we'll only hook up the ones
144  * that are implemented on the current processor
145  */
146 
147 #if defined(CONFIG_PPC64)
148 #define HAS_PPC_PMC_CLASSIC	1
149 #define HAS_PPC_PMC_IBM		1
150 #define HAS_PPC_PMC_PA6T	1
151 #elif defined(CONFIG_6xx)
152 #define HAS_PPC_PMC_CLASSIC	1
153 #define HAS_PPC_PMC_IBM		1
154 #define HAS_PPC_PMC_G4		1
155 #endif
156 
157 
158 #ifdef HAS_PPC_PMC_CLASSIC
159 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
160 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
161 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
162 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
163 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
164 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
165 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
166 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
167 
168 #ifdef HAS_PPC_PMC_G4
169 SYSFS_PMCSETUP(mmcr2, SPRN_MMCR2);
170 #endif
171 
172 #ifdef CONFIG_PPC64
173 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
174 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
175 
176 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
177 SYSFS_PMCSETUP(purr, SPRN_PURR);
178 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
179 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
180 
181 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
182 static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
183 static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
184 static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
185 
186 unsigned long dscr_default = 0;
187 EXPORT_SYMBOL(dscr_default);
188 
189 static ssize_t show_dscr_default(struct sysdev_class *class,
190 		struct sysdev_class_attribute *attr, char *buf)
191 {
192 	return sprintf(buf, "%lx\n", dscr_default);
193 }
194 
195 static ssize_t __used store_dscr_default(struct sysdev_class *class,
196 		struct sysdev_class_attribute *attr, const char *buf,
197 		size_t count)
198 {
199 	unsigned long val;
200 	int ret = 0;
201 
202 	ret = sscanf(buf, "%lx", &val);
203 	if (ret != 1)
204 		return -EINVAL;
205 	dscr_default = val;
206 
207 	return count;
208 }
209 
210 static SYSDEV_CLASS_ATTR(dscr_default, 0600,
211 		show_dscr_default, store_dscr_default);
212 
213 static void sysfs_create_dscr_default(void)
214 {
215 	int err = 0;
216 	if (cpu_has_feature(CPU_FTR_DSCR))
217 		err = sysfs_create_file(&cpu_sysdev_class.kset.kobj,
218 			&attr_dscr_default.attr);
219 }
220 #endif /* CONFIG_PPC64 */
221 
222 #ifdef HAS_PPC_PMC_PA6T
223 SYSFS_PMCSETUP(pa6t_pmc0, SPRN_PA6T_PMC0);
224 SYSFS_PMCSETUP(pa6t_pmc1, SPRN_PA6T_PMC1);
225 SYSFS_PMCSETUP(pa6t_pmc2, SPRN_PA6T_PMC2);
226 SYSFS_PMCSETUP(pa6t_pmc3, SPRN_PA6T_PMC3);
227 SYSFS_PMCSETUP(pa6t_pmc4, SPRN_PA6T_PMC4);
228 SYSFS_PMCSETUP(pa6t_pmc5, SPRN_PA6T_PMC5);
229 #ifdef CONFIG_DEBUG_KERNEL
230 SYSFS_PMCSETUP(hid0, SPRN_HID0);
231 SYSFS_PMCSETUP(hid1, SPRN_HID1);
232 SYSFS_PMCSETUP(hid4, SPRN_HID4);
233 SYSFS_PMCSETUP(hid5, SPRN_HID5);
234 SYSFS_PMCSETUP(ima0, SPRN_PA6T_IMA0);
235 SYSFS_PMCSETUP(ima1, SPRN_PA6T_IMA1);
236 SYSFS_PMCSETUP(ima2, SPRN_PA6T_IMA2);
237 SYSFS_PMCSETUP(ima3, SPRN_PA6T_IMA3);
238 SYSFS_PMCSETUP(ima4, SPRN_PA6T_IMA4);
239 SYSFS_PMCSETUP(ima5, SPRN_PA6T_IMA5);
240 SYSFS_PMCSETUP(ima6, SPRN_PA6T_IMA6);
241 SYSFS_PMCSETUP(ima7, SPRN_PA6T_IMA7);
242 SYSFS_PMCSETUP(ima8, SPRN_PA6T_IMA8);
243 SYSFS_PMCSETUP(ima9, SPRN_PA6T_IMA9);
244 SYSFS_PMCSETUP(imaat, SPRN_PA6T_IMAAT);
245 SYSFS_PMCSETUP(btcr, SPRN_PA6T_BTCR);
246 SYSFS_PMCSETUP(pccr, SPRN_PA6T_PCCR);
247 SYSFS_PMCSETUP(rpccr, SPRN_PA6T_RPCCR);
248 SYSFS_PMCSETUP(der, SPRN_PA6T_DER);
249 SYSFS_PMCSETUP(mer, SPRN_PA6T_MER);
250 SYSFS_PMCSETUP(ber, SPRN_PA6T_BER);
251 SYSFS_PMCSETUP(ier, SPRN_PA6T_IER);
252 SYSFS_PMCSETUP(sier, SPRN_PA6T_SIER);
253 SYSFS_PMCSETUP(siar, SPRN_PA6T_SIAR);
254 SYSFS_PMCSETUP(tsr0, SPRN_PA6T_TSR0);
255 SYSFS_PMCSETUP(tsr1, SPRN_PA6T_TSR1);
256 SYSFS_PMCSETUP(tsr2, SPRN_PA6T_TSR2);
257 SYSFS_PMCSETUP(tsr3, SPRN_PA6T_TSR3);
258 #endif /* CONFIG_DEBUG_KERNEL */
259 #endif /* HAS_PPC_PMC_PA6T */
260 
261 #ifdef HAS_PPC_PMC_IBM
262 static struct sysdev_attribute ibm_common_attrs[] = {
263 	_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
264 	_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
265 };
266 #endif /* HAS_PPC_PMC_G4 */
267 
268 #ifdef HAS_PPC_PMC_G4
269 static struct sysdev_attribute g4_common_attrs[] = {
270 	_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
271 	_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
272 	_SYSDEV_ATTR(mmcr2, 0600, show_mmcr2, store_mmcr2),
273 };
274 #endif /* HAS_PPC_PMC_G4 */
275 
276 static struct sysdev_attribute classic_pmc_attrs[] = {
277 	_SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1),
278 	_SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2),
279 	_SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3),
280 	_SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4),
281 	_SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5),
282 	_SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6),
283 #ifdef CONFIG_PPC64
284 	_SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7),
285 	_SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8),
286 #endif
287 };
288 
289 #ifdef HAS_PPC_PMC_PA6T
290 static struct sysdev_attribute pa6t_attrs[] = {
291 	_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
292 	_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
293 	_SYSDEV_ATTR(pmc0, 0600, show_pa6t_pmc0, store_pa6t_pmc0),
294 	_SYSDEV_ATTR(pmc1, 0600, show_pa6t_pmc1, store_pa6t_pmc1),
295 	_SYSDEV_ATTR(pmc2, 0600, show_pa6t_pmc2, store_pa6t_pmc2),
296 	_SYSDEV_ATTR(pmc3, 0600, show_pa6t_pmc3, store_pa6t_pmc3),
297 	_SYSDEV_ATTR(pmc4, 0600, show_pa6t_pmc4, store_pa6t_pmc4),
298 	_SYSDEV_ATTR(pmc5, 0600, show_pa6t_pmc5, store_pa6t_pmc5),
299 #ifdef CONFIG_DEBUG_KERNEL
300 	_SYSDEV_ATTR(hid0, 0600, show_hid0, store_hid0),
301 	_SYSDEV_ATTR(hid1, 0600, show_hid1, store_hid1),
302 	_SYSDEV_ATTR(hid4, 0600, show_hid4, store_hid4),
303 	_SYSDEV_ATTR(hid5, 0600, show_hid5, store_hid5),
304 	_SYSDEV_ATTR(ima0, 0600, show_ima0, store_ima0),
305 	_SYSDEV_ATTR(ima1, 0600, show_ima1, store_ima1),
306 	_SYSDEV_ATTR(ima2, 0600, show_ima2, store_ima2),
307 	_SYSDEV_ATTR(ima3, 0600, show_ima3, store_ima3),
308 	_SYSDEV_ATTR(ima4, 0600, show_ima4, store_ima4),
309 	_SYSDEV_ATTR(ima5, 0600, show_ima5, store_ima5),
310 	_SYSDEV_ATTR(ima6, 0600, show_ima6, store_ima6),
311 	_SYSDEV_ATTR(ima7, 0600, show_ima7, store_ima7),
312 	_SYSDEV_ATTR(ima8, 0600, show_ima8, store_ima8),
313 	_SYSDEV_ATTR(ima9, 0600, show_ima9, store_ima9),
314 	_SYSDEV_ATTR(imaat, 0600, show_imaat, store_imaat),
315 	_SYSDEV_ATTR(btcr, 0600, show_btcr, store_btcr),
316 	_SYSDEV_ATTR(pccr, 0600, show_pccr, store_pccr),
317 	_SYSDEV_ATTR(rpccr, 0600, show_rpccr, store_rpccr),
318 	_SYSDEV_ATTR(der, 0600, show_der, store_der),
319 	_SYSDEV_ATTR(mer, 0600, show_mer, store_mer),
320 	_SYSDEV_ATTR(ber, 0600, show_ber, store_ber),
321 	_SYSDEV_ATTR(ier, 0600, show_ier, store_ier),
322 	_SYSDEV_ATTR(sier, 0600, show_sier, store_sier),
323 	_SYSDEV_ATTR(siar, 0600, show_siar, store_siar),
324 	_SYSDEV_ATTR(tsr0, 0600, show_tsr0, store_tsr0),
325 	_SYSDEV_ATTR(tsr1, 0600, show_tsr1, store_tsr1),
326 	_SYSDEV_ATTR(tsr2, 0600, show_tsr2, store_tsr2),
327 	_SYSDEV_ATTR(tsr3, 0600, show_tsr3, store_tsr3),
328 #endif /* CONFIG_DEBUG_KERNEL */
329 };
330 #endif /* HAS_PPC_PMC_PA6T */
331 #endif /* HAS_PPC_PMC_CLASSIC */
332 
333 static void __cpuinit register_cpu_online(unsigned int cpu)
334 {
335 	struct cpu *c = &per_cpu(cpu_devices, cpu);
336 	struct sys_device *s = &c->sysdev;
337 	struct sysdev_attribute *attrs, *pmc_attrs;
338 	int i, nattrs;
339 
340 #ifdef CONFIG_PPC64
341 	if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
342 			cpu_has_feature(CPU_FTR_SMT))
343 		sysdev_create_file(s, &attr_smt_snooze_delay);
344 #endif
345 
346 	/* PMC stuff */
347 	switch (cur_cpu_spec->pmc_type) {
348 #ifdef HAS_PPC_PMC_IBM
349 	case PPC_PMC_IBM:
350 		attrs = ibm_common_attrs;
351 		nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
352 		pmc_attrs = classic_pmc_attrs;
353 		break;
354 #endif /* HAS_PPC_PMC_IBM */
355 #ifdef HAS_PPC_PMC_G4
356 	case PPC_PMC_G4:
357 		attrs = g4_common_attrs;
358 		nattrs = sizeof(g4_common_attrs) / sizeof(struct sysdev_attribute);
359 		pmc_attrs = classic_pmc_attrs;
360 		break;
361 #endif /* HAS_PPC_PMC_G4 */
362 #ifdef HAS_PPC_PMC_PA6T
363 	case PPC_PMC_PA6T:
364 		/* PA Semi starts counting at PMC0 */
365 		attrs = pa6t_attrs;
366 		nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
367 		pmc_attrs = NULL;
368 		break;
369 #endif /* HAS_PPC_PMC_PA6T */
370 	default:
371 		attrs = NULL;
372 		nattrs = 0;
373 		pmc_attrs = NULL;
374 	}
375 
376 	for (i = 0; i < nattrs; i++)
377 		sysdev_create_file(s, &attrs[i]);
378 
379 	if (pmc_attrs)
380 		for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
381 			sysdev_create_file(s, &pmc_attrs[i]);
382 
383 #ifdef CONFIG_PPC64
384 	if (cpu_has_feature(CPU_FTR_MMCRA))
385 		sysdev_create_file(s, &attr_mmcra);
386 
387 	if (cpu_has_feature(CPU_FTR_PURR))
388 		sysdev_create_file(s, &attr_purr);
389 
390 	if (cpu_has_feature(CPU_FTR_SPURR))
391 		sysdev_create_file(s, &attr_spurr);
392 
393 	if (cpu_has_feature(CPU_FTR_DSCR))
394 		sysdev_create_file(s, &attr_dscr);
395 #endif /* CONFIG_PPC64 */
396 
397 	cacheinfo_cpu_online(cpu);
398 }
399 
400 #ifdef CONFIG_HOTPLUG_CPU
401 static void unregister_cpu_online(unsigned int cpu)
402 {
403 	struct cpu *c = &per_cpu(cpu_devices, cpu);
404 	struct sys_device *s = &c->sysdev;
405 	struct sysdev_attribute *attrs, *pmc_attrs;
406 	int i, nattrs;
407 
408 	BUG_ON(!c->hotpluggable);
409 
410 #ifdef CONFIG_PPC64
411 	if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
412 			cpu_has_feature(CPU_FTR_SMT))
413 		sysdev_remove_file(s, &attr_smt_snooze_delay);
414 #endif
415 
416 	/* PMC stuff */
417 	switch (cur_cpu_spec->pmc_type) {
418 #ifdef HAS_PPC_PMC_IBM
419 	case PPC_PMC_IBM:
420 		attrs = ibm_common_attrs;
421 		nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
422 		pmc_attrs = classic_pmc_attrs;
423 		break;
424 #endif /* HAS_PPC_PMC_IBM */
425 #ifdef HAS_PPC_PMC_G4
426 	case PPC_PMC_G4:
427 		attrs = g4_common_attrs;
428 		nattrs = sizeof(g4_common_attrs) / sizeof(struct sysdev_attribute);
429 		pmc_attrs = classic_pmc_attrs;
430 		break;
431 #endif /* HAS_PPC_PMC_G4 */
432 #ifdef HAS_PPC_PMC_PA6T
433 	case PPC_PMC_PA6T:
434 		/* PA Semi starts counting at PMC0 */
435 		attrs = pa6t_attrs;
436 		nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
437 		pmc_attrs = NULL;
438 		break;
439 #endif /* HAS_PPC_PMC_PA6T */
440 	default:
441 		attrs = NULL;
442 		nattrs = 0;
443 		pmc_attrs = NULL;
444 	}
445 
446 	for (i = 0; i < nattrs; i++)
447 		sysdev_remove_file(s, &attrs[i]);
448 
449 	if (pmc_attrs)
450 		for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
451 			sysdev_remove_file(s, &pmc_attrs[i]);
452 
453 #ifdef CONFIG_PPC64
454 	if (cpu_has_feature(CPU_FTR_MMCRA))
455 		sysdev_remove_file(s, &attr_mmcra);
456 
457 	if (cpu_has_feature(CPU_FTR_PURR))
458 		sysdev_remove_file(s, &attr_purr);
459 
460 	if (cpu_has_feature(CPU_FTR_SPURR))
461 		sysdev_remove_file(s, &attr_spurr);
462 
463 	if (cpu_has_feature(CPU_FTR_DSCR))
464 		sysdev_remove_file(s, &attr_dscr);
465 #endif /* CONFIG_PPC64 */
466 
467 	cacheinfo_cpu_offline(cpu);
468 }
469 
470 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
471 ssize_t arch_cpu_probe(const char *buf, size_t count)
472 {
473 	if (ppc_md.cpu_probe)
474 		return ppc_md.cpu_probe(buf, count);
475 
476 	return -EINVAL;
477 }
478 
479 ssize_t arch_cpu_release(const char *buf, size_t count)
480 {
481 	if (ppc_md.cpu_release)
482 		return ppc_md.cpu_release(buf, count);
483 
484 	return -EINVAL;
485 }
486 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
487 
488 #endif /* CONFIG_HOTPLUG_CPU */
489 
490 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
491 				      unsigned long action, void *hcpu)
492 {
493 	unsigned int cpu = (unsigned int)(long)hcpu;
494 
495 	switch (action) {
496 	case CPU_ONLINE:
497 	case CPU_ONLINE_FROZEN:
498 		register_cpu_online(cpu);
499 		break;
500 #ifdef CONFIG_HOTPLUG_CPU
501 	case CPU_DEAD:
502 	case CPU_DEAD_FROZEN:
503 		unregister_cpu_online(cpu);
504 		break;
505 #endif
506 	}
507 	return NOTIFY_OK;
508 }
509 
510 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
511 	.notifier_call	= sysfs_cpu_notify,
512 };
513 
514 static DEFINE_MUTEX(cpu_mutex);
515 
516 int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
517 {
518 	int cpu;
519 
520 	mutex_lock(&cpu_mutex);
521 
522 	for_each_possible_cpu(cpu) {
523 		sysdev_create_file(get_cpu_sysdev(cpu), attr);
524 	}
525 
526 	mutex_unlock(&cpu_mutex);
527 	return 0;
528 }
529 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
530 
531 int cpu_add_sysdev_attr_group(struct attribute_group *attrs)
532 {
533 	int cpu;
534 	struct sys_device *sysdev;
535 	int ret;
536 
537 	mutex_lock(&cpu_mutex);
538 
539 	for_each_possible_cpu(cpu) {
540 		sysdev = get_cpu_sysdev(cpu);
541 		ret = sysfs_create_group(&sysdev->kobj, attrs);
542 		WARN_ON(ret != 0);
543 	}
544 
545 	mutex_unlock(&cpu_mutex);
546 	return 0;
547 }
548 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr_group);
549 
550 
551 void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
552 {
553 	int cpu;
554 
555 	mutex_lock(&cpu_mutex);
556 
557 	for_each_possible_cpu(cpu) {
558 		sysdev_remove_file(get_cpu_sysdev(cpu), attr);
559 	}
560 
561 	mutex_unlock(&cpu_mutex);
562 }
563 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
564 
565 void cpu_remove_sysdev_attr_group(struct attribute_group *attrs)
566 {
567 	int cpu;
568 	struct sys_device *sysdev;
569 
570 	mutex_lock(&cpu_mutex);
571 
572 	for_each_possible_cpu(cpu) {
573 		sysdev = get_cpu_sysdev(cpu);
574 		sysfs_remove_group(&sysdev->kobj, attrs);
575 	}
576 
577 	mutex_unlock(&cpu_mutex);
578 }
579 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr_group);
580 
581 
582 /* NUMA stuff */
583 
584 #ifdef CONFIG_NUMA
585 static void register_nodes(void)
586 {
587 	int i;
588 
589 	for (i = 0; i < MAX_NUMNODES; i++)
590 		register_one_node(i);
591 }
592 
593 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
594 {
595 	struct node *node = &node_devices[nid];
596 	return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
597 			kobject_name(&dev->kobj));
598 }
599 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
600 
601 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
602 {
603 	struct node *node = &node_devices[nid];
604 	sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
605 }
606 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
607 
608 #else
609 static void register_nodes(void)
610 {
611 	return;
612 }
613 
614 #endif
615 
616 /* Only valid if CPU is present. */
617 static ssize_t show_physical_id(struct sys_device *dev,
618 				struct sysdev_attribute *attr, char *buf)
619 {
620 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
621 
622 	return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
623 }
624 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
625 
626 static int __init topology_init(void)
627 {
628 	int cpu;
629 
630 	register_nodes();
631 	register_cpu_notifier(&sysfs_cpu_nb);
632 
633 	for_each_possible_cpu(cpu) {
634 		struct cpu *c = &per_cpu(cpu_devices, cpu);
635 
636 		/*
637 		 * For now, we just see if the system supports making
638 		 * the RTAS calls for CPU hotplug.  But, there may be a
639 		 * more comprehensive way to do this for an individual
640 		 * CPU.  For instance, the boot cpu might never be valid
641 		 * for hotplugging.
642 		 */
643 		if (ppc_md.cpu_die)
644 			c->hotpluggable = 1;
645 
646 		if (cpu_online(cpu) || c->hotpluggable) {
647 			register_cpu(c, cpu);
648 
649 			sysdev_create_file(&c->sysdev, &attr_physical_id);
650 		}
651 
652 		if (cpu_online(cpu))
653 			register_cpu_online(cpu);
654 	}
655 #ifdef CONFIG_PPC64
656 	sysfs_create_dscr_default();
657 #endif /* CONFIG_PPC64 */
658 
659 	return 0;
660 }
661 subsys_initcall(topology_init);
662