xref: /linux/arch/powerpc/kernel/sysfs.c (revision b0148a98ec5151fec82064d95f11eb9efbc628ea)
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/module.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/paca.h>
19 #include <asm/lppaca.h>
20 #include <asm/machdep.h>
21 #include <asm/smp.h>
22 
23 static DEFINE_PER_CPU(struct cpu, cpu_devices);
24 
25 /* SMT stuff */
26 
27 #ifdef CONFIG_PPC_MULTIPLATFORM
28 /* Time in microseconds we delay before sleeping in the idle loop */
29 DEFINE_PER_CPU(unsigned long, smt_snooze_delay) = { 100 };
30 
31 static ssize_t store_smt_snooze_delay(struct sys_device *dev, const char *buf,
32 				      size_t count)
33 {
34 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
35 	ssize_t ret;
36 	unsigned long snooze;
37 
38 	ret = sscanf(buf, "%lu", &snooze);
39 	if (ret != 1)
40 		return -EINVAL;
41 
42 	per_cpu(smt_snooze_delay, cpu->sysdev.id) = snooze;
43 
44 	return count;
45 }
46 
47 static ssize_t show_smt_snooze_delay(struct sys_device *dev, char *buf)
48 {
49 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
50 
51 	return sprintf(buf, "%lu\n", per_cpu(smt_snooze_delay, cpu->sysdev.id));
52 }
53 
54 static SYSDEV_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
55 		   store_smt_snooze_delay);
56 
57 /* Only parse OF options if the matching cmdline option was not specified */
58 static int smt_snooze_cmdline;
59 
60 static int __init smt_setup(void)
61 {
62 	struct device_node *options;
63 	const unsigned int *val;
64 	unsigned int cpu;
65 
66 	if (!cpu_has_feature(CPU_FTR_SMT))
67 		return -ENODEV;
68 
69 	options = find_path_device("/options");
70 	if (!options)
71 		return -ENODEV;
72 
73 	val = get_property(options, "ibm,smt-snooze-delay", NULL);
74 	if (!smt_snooze_cmdline && val) {
75 		for_each_possible_cpu(cpu)
76 			per_cpu(smt_snooze_delay, cpu) = *val;
77 	}
78 
79 	return 0;
80 }
81 __initcall(smt_setup);
82 
83 static int __init setup_smt_snooze_delay(char *str)
84 {
85 	unsigned int cpu;
86 	int snooze;
87 
88 	if (!cpu_has_feature(CPU_FTR_SMT))
89 		return 1;
90 
91 	smt_snooze_cmdline = 1;
92 
93 	if (get_option(&str, &snooze)) {
94 		for_each_possible_cpu(cpu)
95 			per_cpu(smt_snooze_delay, cpu) = snooze;
96 	}
97 
98 	return 1;
99 }
100 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
101 
102 #endif /* CONFIG_PPC_MULTIPLATFORM */
103 
104 /*
105  * Enabling PMCs will slow partition context switch times so we only do
106  * it the first time we write to the PMCs.
107  */
108 
109 static DEFINE_PER_CPU(char, pmcs_enabled);
110 
111 void ppc64_enable_pmcs(void)
112 {
113 	/* Only need to enable them once */
114 	if (__get_cpu_var(pmcs_enabled))
115 		return;
116 
117 	__get_cpu_var(pmcs_enabled) = 1;
118 
119 	if (ppc_md.enable_pmcs)
120 		ppc_md.enable_pmcs();
121 }
122 EXPORT_SYMBOL(ppc64_enable_pmcs);
123 
124 /* XXX convert to rusty's on_one_cpu */
125 static unsigned long run_on_cpu(unsigned long cpu,
126 			        unsigned long (*func)(unsigned long),
127 				unsigned long arg)
128 {
129 	cpumask_t old_affinity = current->cpus_allowed;
130 	unsigned long ret;
131 
132 	/* should return -EINVAL to userspace */
133 	if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
134 		return 0;
135 
136 	ret = func(arg);
137 
138 	set_cpus_allowed(current, old_affinity);
139 
140 	return ret;
141 }
142 
143 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
144 static unsigned long read_##NAME(unsigned long junk) \
145 { \
146 	return mfspr(ADDRESS); \
147 } \
148 static unsigned long write_##NAME(unsigned long val) \
149 { \
150 	ppc64_enable_pmcs(); \
151 	mtspr(ADDRESS, val); \
152 	return 0; \
153 } \
154 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
155 { \
156 	struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
157 	unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
158 	return sprintf(buf, "%lx\n", val); \
159 } \
160 static ssize_t __attribute_used__ \
161 	store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
162 { \
163 	struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
164 	unsigned long val; \
165 	int ret = sscanf(buf, "%lx", &val); \
166 	if (ret != 1) \
167 		return -EINVAL; \
168 	run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
169 	return count; \
170 }
171 
172 
173 /* Let's define all possible registers, we'll only hook up the ones
174  * that are implemented on the current processor
175  */
176 
177 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
178 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
179 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
180 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
181 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
182 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
183 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
184 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
185 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
186 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
187 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
188 SYSFS_PMCSETUP(purr, SPRN_PURR);
189 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
190 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
191 
192 SYSFS_PMCSETUP(pa6t_pmc0, PA6T_SPRN_PMC0);
193 SYSFS_PMCSETUP(pa6t_pmc1, PA6T_SPRN_PMC1);
194 SYSFS_PMCSETUP(pa6t_pmc2, PA6T_SPRN_PMC2);
195 SYSFS_PMCSETUP(pa6t_pmc3, PA6T_SPRN_PMC3);
196 SYSFS_PMCSETUP(pa6t_pmc4, PA6T_SPRN_PMC4);
197 SYSFS_PMCSETUP(pa6t_pmc5, PA6T_SPRN_PMC5);
198 
199 
200 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
201 static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
202 static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
203 static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
204 
205 static struct sysdev_attribute ibm_common_attrs[] = {
206 	_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
207 	_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
208 };
209 
210 static struct sysdev_attribute ibm_pmc_attrs[] = {
211 	_SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1),
212 	_SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2),
213 	_SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3),
214 	_SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4),
215 	_SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5),
216 	_SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6),
217 	_SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7),
218 	_SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8),
219 };
220 
221 static struct sysdev_attribute pa6t_attrs[] = {
222 	_SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
223 	_SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
224 	_SYSDEV_ATTR(pmc0, 0600, show_pa6t_pmc0, store_pa6t_pmc0),
225 	_SYSDEV_ATTR(pmc1, 0600, show_pa6t_pmc1, store_pa6t_pmc1),
226 	_SYSDEV_ATTR(pmc2, 0600, show_pa6t_pmc2, store_pa6t_pmc2),
227 	_SYSDEV_ATTR(pmc3, 0600, show_pa6t_pmc3, store_pa6t_pmc3),
228 	_SYSDEV_ATTR(pmc4, 0600, show_pa6t_pmc4, store_pa6t_pmc4),
229 	_SYSDEV_ATTR(pmc5, 0600, show_pa6t_pmc5, store_pa6t_pmc5),
230 };
231 
232 
233 static void register_cpu_online(unsigned int cpu)
234 {
235 	struct cpu *c = &per_cpu(cpu_devices, cpu);
236 	struct sys_device *s = &c->sysdev;
237 	struct sysdev_attribute *attrs, *pmc_attrs;
238 	int i, nattrs;
239 
240 	if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
241 			cpu_has_feature(CPU_FTR_SMT))
242 		sysdev_create_file(s, &attr_smt_snooze_delay);
243 
244 	/* PMC stuff */
245 	switch (cur_cpu_spec->pmc_type) {
246 	case PPC_PMC_IBM:
247 		attrs = ibm_common_attrs;
248 		nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
249 		pmc_attrs = ibm_pmc_attrs;
250 		break;
251 	case PPC_PMC_PA6T:
252 		/* PA Semi starts counting at PMC0 */
253 		attrs = pa6t_attrs;
254 		nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
255 		pmc_attrs = NULL;
256 		break;
257 	default:
258 		attrs = NULL;
259 		nattrs = 0;
260 		pmc_attrs = NULL;
261 	}
262 
263 	for (i = 0; i < nattrs; i++)
264 		sysdev_create_file(s, &attrs[i]);
265 
266 	if (pmc_attrs)
267 		for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
268 			sysdev_create_file(s, &pmc_attrs[i]);
269 
270 	if (cpu_has_feature(CPU_FTR_MMCRA))
271 		sysdev_create_file(s, &attr_mmcra);
272 
273 	if (cpu_has_feature(CPU_FTR_PURR))
274 		sysdev_create_file(s, &attr_purr);
275 
276 	if (cpu_has_feature(CPU_FTR_SPURR))
277 		sysdev_create_file(s, &attr_spurr);
278 
279 	if (cpu_has_feature(CPU_FTR_DSCR))
280 		sysdev_create_file(s, &attr_dscr);
281 }
282 
283 #ifdef CONFIG_HOTPLUG_CPU
284 static void unregister_cpu_online(unsigned int cpu)
285 {
286 	struct cpu *c = &per_cpu(cpu_devices, cpu);
287 	struct sys_device *s = &c->sysdev;
288 	struct sysdev_attribute *attrs, *pmc_attrs;
289 	int i, nattrs;
290 
291 	BUG_ON(!c->hotpluggable);
292 
293 	if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
294 			cpu_has_feature(CPU_FTR_SMT))
295 		sysdev_remove_file(s, &attr_smt_snooze_delay);
296 
297 	/* PMC stuff */
298 	switch (cur_cpu_spec->pmc_type) {
299 	case PPC_PMC_IBM:
300 		attrs = ibm_common_attrs;
301 		nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
302 		pmc_attrs = ibm_pmc_attrs;
303 		break;
304 	case PPC_PMC_PA6T:
305 		/* PA Semi starts counting at PMC0 */
306 		attrs = pa6t_attrs;
307 		nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
308 		pmc_attrs = NULL;
309 		break;
310 	default:
311 		attrs = NULL;
312 		nattrs = 0;
313 		pmc_attrs = NULL;
314 	}
315 
316 	for (i = 0; i < nattrs; i++)
317 		sysdev_remove_file(s, &attrs[i]);
318 
319 	if (pmc_attrs)
320 		for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
321 			sysdev_remove_file(s, &pmc_attrs[i]);
322 
323 	if (cpu_has_feature(CPU_FTR_MMCRA))
324 		sysdev_remove_file(s, &attr_mmcra);
325 
326 	if (cpu_has_feature(CPU_FTR_PURR))
327 		sysdev_remove_file(s, &attr_purr);
328 
329 	if (cpu_has_feature(CPU_FTR_SPURR))
330 		sysdev_remove_file(s, &attr_spurr);
331 
332 	if (cpu_has_feature(CPU_FTR_DSCR))
333 		sysdev_remove_file(s, &attr_dscr);
334 }
335 #endif /* CONFIG_HOTPLUG_CPU */
336 
337 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
338 				      unsigned long action, void *hcpu)
339 {
340 	unsigned int cpu = (unsigned int)(long)hcpu;
341 
342 	switch (action) {
343 	case CPU_ONLINE:
344 		register_cpu_online(cpu);
345 		break;
346 #ifdef CONFIG_HOTPLUG_CPU
347 	case CPU_DEAD:
348 		unregister_cpu_online(cpu);
349 		break;
350 #endif
351 	}
352 	return NOTIFY_OK;
353 }
354 
355 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
356 	.notifier_call	= sysfs_cpu_notify,
357 };
358 
359 static DEFINE_MUTEX(cpu_mutex);
360 
361 int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
362 {
363 	int cpu;
364 
365 	mutex_lock(&cpu_mutex);
366 
367 	for_each_possible_cpu(cpu) {
368 		sysdev_create_file(get_cpu_sysdev(cpu), attr);
369 	}
370 
371 	mutex_unlock(&cpu_mutex);
372 	return 0;
373 }
374 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
375 
376 int cpu_add_sysdev_attr_group(struct attribute_group *attrs)
377 {
378 	int cpu;
379 	struct sys_device *sysdev;
380 
381 	mutex_lock(&cpu_mutex);
382 
383 	for_each_possible_cpu(cpu) {
384 		sysdev = get_cpu_sysdev(cpu);
385 		sysfs_create_group(&sysdev->kobj, attrs);
386 	}
387 
388 	mutex_unlock(&cpu_mutex);
389 	return 0;
390 }
391 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr_group);
392 
393 
394 void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
395 {
396 	int cpu;
397 
398 	mutex_lock(&cpu_mutex);
399 
400 	for_each_possible_cpu(cpu) {
401 		sysdev_remove_file(get_cpu_sysdev(cpu), attr);
402 	}
403 
404 	mutex_unlock(&cpu_mutex);
405 }
406 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
407 
408 void cpu_remove_sysdev_attr_group(struct attribute_group *attrs)
409 {
410 	int cpu;
411 	struct sys_device *sysdev;
412 
413 	mutex_lock(&cpu_mutex);
414 
415 	for_each_possible_cpu(cpu) {
416 		sysdev = get_cpu_sysdev(cpu);
417 		sysfs_remove_group(&sysdev->kobj, attrs);
418 	}
419 
420 	mutex_unlock(&cpu_mutex);
421 }
422 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr_group);
423 
424 
425 /* NUMA stuff */
426 
427 #ifdef CONFIG_NUMA
428 static void register_nodes(void)
429 {
430 	int i;
431 
432 	for (i = 0; i < MAX_NUMNODES; i++)
433 		register_one_node(i);
434 }
435 
436 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
437 {
438 	struct node *node = &node_devices[nid];
439 	return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
440 			kobject_name(&dev->kobj));
441 }
442 
443 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
444 {
445 	struct node *node = &node_devices[nid];
446 	sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
447 }
448 
449 #else
450 static void register_nodes(void)
451 {
452 	return;
453 }
454 
455 #endif
456 
457 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
458 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
459 
460 /* Only valid if CPU is present. */
461 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
462 {
463 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
464 
465 	return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
466 }
467 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
468 
469 static int __init topology_init(void)
470 {
471 	int cpu;
472 
473 	register_nodes();
474 	register_cpu_notifier(&sysfs_cpu_nb);
475 
476 	for_each_possible_cpu(cpu) {
477 		struct cpu *c = &per_cpu(cpu_devices, cpu);
478 
479 		/*
480 		 * For now, we just see if the system supports making
481 		 * the RTAS calls for CPU hotplug.  But, there may be a
482 		 * more comprehensive way to do this for an individual
483 		 * CPU.  For instance, the boot cpu might never be valid
484 		 * for hotplugging.
485 		 */
486 		if (ppc_md.cpu_die)
487 			c->hotpluggable = 1;
488 
489 		if (cpu_online(cpu) || c->hotpluggable) {
490 			register_cpu(c, cpu);
491 
492 			sysdev_create_file(&c->sysdev, &attr_physical_id);
493 		}
494 
495 		if (cpu_online(cpu))
496 			register_cpu_online(cpu);
497 	}
498 
499 	return 0;
500 }
501 __initcall(topology_init);
502