xref: /linux/arch/powerpc/kernel/sysfs.c (revision 6e8331ac6973435b1e7604c30f2ad394035b46e1)
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 /* default to snooze disabled */
29 DEFINE_PER_CPU(unsigned long, smt_snooze_delay);
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 	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 = (unsigned int *)get_property(options, "ibm,smt-snooze-delay",
74 					   NULL);
75 	if (!smt_snooze_cmdline && val) {
76 		for_each_possible_cpu(cpu)
77 			per_cpu(smt_snooze_delay, cpu) = *val;
78 	}
79 
80 	return 0;
81 }
82 __initcall(smt_setup);
83 
84 static int __init setup_smt_snooze_delay(char *str)
85 {
86 	unsigned int cpu;
87 	int snooze;
88 
89 	if (!cpu_has_feature(CPU_FTR_SMT))
90 		return 1;
91 
92 	smt_snooze_cmdline = 1;
93 
94 	if (get_option(&str, &snooze)) {
95 		for_each_possible_cpu(cpu)
96 			per_cpu(smt_snooze_delay, cpu) = snooze;
97 	}
98 
99 	return 1;
100 }
101 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
102 
103 #endif /* CONFIG_PPC_MULTIPLATFORM */
104 
105 /*
106  * Enabling PMCs will slow partition context switch times so we only do
107  * it the first time we write to the PMCs.
108  */
109 
110 static DEFINE_PER_CPU(char, pmcs_enabled);
111 
112 void ppc64_enable_pmcs(void)
113 {
114 	/* Only need to enable them once */
115 	if (__get_cpu_var(pmcs_enabled))
116 		return;
117 
118 	__get_cpu_var(pmcs_enabled) = 1;
119 
120 	if (ppc_md.enable_pmcs)
121 		ppc_md.enable_pmcs();
122 }
123 EXPORT_SYMBOL(ppc64_enable_pmcs);
124 
125 /* XXX convert to rusty's on_one_cpu */
126 static unsigned long run_on_cpu(unsigned long cpu,
127 			        unsigned long (*func)(unsigned long),
128 				unsigned long arg)
129 {
130 	cpumask_t old_affinity = current->cpus_allowed;
131 	unsigned long ret;
132 
133 	/* should return -EINVAL to userspace */
134 	if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
135 		return 0;
136 
137 	ret = func(arg);
138 
139 	set_cpus_allowed(current, old_affinity);
140 
141 	return ret;
142 }
143 
144 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
145 static unsigned long read_##NAME(unsigned long junk) \
146 { \
147 	return mfspr(ADDRESS); \
148 } \
149 static unsigned long write_##NAME(unsigned long val) \
150 { \
151 	ppc64_enable_pmcs(); \
152 	mtspr(ADDRESS, val); \
153 	return 0; \
154 } \
155 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
156 { \
157 	struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
158 	unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
159 	return sprintf(buf, "%lx\n", val); \
160 } \
161 static ssize_t __attribute_used__ \
162 	store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
163 { \
164 	struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
165 	unsigned long val; \
166 	int ret = sscanf(buf, "%lx", &val); \
167 	if (ret != 1) \
168 		return -EINVAL; \
169 	run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
170 	return count; \
171 }
172 
173 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
174 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
175 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
176 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
177 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
178 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
179 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
180 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
181 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
182 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
183 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
184 SYSFS_PMCSETUP(purr, SPRN_PURR);
185 
186 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
187 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
188 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
189 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
190 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
191 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
192 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
193 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
194 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
195 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
196 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
197 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
198 
199 static void register_cpu_online(unsigned int cpu)
200 {
201 	struct cpu *c = &per_cpu(cpu_devices, cpu);
202 	struct sys_device *s = &c->sysdev;
203 
204 #ifndef CONFIG_PPC_ISERIES
205 	if (cpu_has_feature(CPU_FTR_SMT))
206 		sysdev_create_file(s, &attr_smt_snooze_delay);
207 #endif
208 
209 	/* PMC stuff */
210 
211 	sysdev_create_file(s, &attr_mmcr0);
212 	sysdev_create_file(s, &attr_mmcr1);
213 
214 	if (cpu_has_feature(CPU_FTR_MMCRA))
215 		sysdev_create_file(s, &attr_mmcra);
216 
217 	if (cur_cpu_spec->num_pmcs >= 1)
218 		sysdev_create_file(s, &attr_pmc1);
219 	if (cur_cpu_spec->num_pmcs >= 2)
220 		sysdev_create_file(s, &attr_pmc2);
221 	if (cur_cpu_spec->num_pmcs >= 3)
222 		sysdev_create_file(s, &attr_pmc3);
223 	if (cur_cpu_spec->num_pmcs >= 4)
224 		sysdev_create_file(s, &attr_pmc4);
225 	if (cur_cpu_spec->num_pmcs >= 5)
226 		sysdev_create_file(s, &attr_pmc5);
227 	if (cur_cpu_spec->num_pmcs >= 6)
228 		sysdev_create_file(s, &attr_pmc6);
229 	if (cur_cpu_spec->num_pmcs >= 7)
230 		sysdev_create_file(s, &attr_pmc7);
231 	if (cur_cpu_spec->num_pmcs >= 8)
232 		sysdev_create_file(s, &attr_pmc8);
233 
234 	if (cpu_has_feature(CPU_FTR_SMT))
235 		sysdev_create_file(s, &attr_purr);
236 }
237 
238 #ifdef CONFIG_HOTPLUG_CPU
239 static void unregister_cpu_online(unsigned int cpu)
240 {
241 	struct cpu *c = &per_cpu(cpu_devices, cpu);
242 	struct sys_device *s = &c->sysdev;
243 
244 	BUG_ON(c->no_control);
245 
246 #ifndef CONFIG_PPC_ISERIES
247 	if (cpu_has_feature(CPU_FTR_SMT))
248 		sysdev_remove_file(s, &attr_smt_snooze_delay);
249 #endif
250 
251 	/* PMC stuff */
252 
253 	sysdev_remove_file(s, &attr_mmcr0);
254 	sysdev_remove_file(s, &attr_mmcr1);
255 
256 	if (cpu_has_feature(CPU_FTR_MMCRA))
257 		sysdev_remove_file(s, &attr_mmcra);
258 
259 	if (cur_cpu_spec->num_pmcs >= 1)
260 		sysdev_remove_file(s, &attr_pmc1);
261 	if (cur_cpu_spec->num_pmcs >= 2)
262 		sysdev_remove_file(s, &attr_pmc2);
263 	if (cur_cpu_spec->num_pmcs >= 3)
264 		sysdev_remove_file(s, &attr_pmc3);
265 	if (cur_cpu_spec->num_pmcs >= 4)
266 		sysdev_remove_file(s, &attr_pmc4);
267 	if (cur_cpu_spec->num_pmcs >= 5)
268 		sysdev_remove_file(s, &attr_pmc5);
269 	if (cur_cpu_spec->num_pmcs >= 6)
270 		sysdev_remove_file(s, &attr_pmc6);
271 	if (cur_cpu_spec->num_pmcs >= 7)
272 		sysdev_remove_file(s, &attr_pmc7);
273 	if (cur_cpu_spec->num_pmcs >= 8)
274 		sysdev_remove_file(s, &attr_pmc8);
275 
276 	if (cpu_has_feature(CPU_FTR_SMT))
277 		sysdev_remove_file(s, &attr_purr);
278 }
279 #endif /* CONFIG_HOTPLUG_CPU */
280 
281 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
282 				      unsigned long action, void *hcpu)
283 {
284 	unsigned int cpu = (unsigned int)(long)hcpu;
285 
286 	switch (action) {
287 	case CPU_ONLINE:
288 		register_cpu_online(cpu);
289 		break;
290 #ifdef CONFIG_HOTPLUG_CPU
291 	case CPU_DEAD:
292 		unregister_cpu_online(cpu);
293 		break;
294 #endif
295 	}
296 	return NOTIFY_OK;
297 }
298 
299 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
300 	.notifier_call	= sysfs_cpu_notify,
301 };
302 
303 /* NUMA stuff */
304 
305 #ifdef CONFIG_NUMA
306 static void register_nodes(void)
307 {
308 	int i;
309 
310 	for (i = 0; i < MAX_NUMNODES; i++)
311 		register_one_node(i);
312 }
313 
314 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
315 {
316 	struct node *node = &node_devices[nid];
317 	return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
318 			kobject_name(&dev->kobj));
319 }
320 
321 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
322 {
323 	struct node *node = &node_devices[nid];
324 	sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
325 }
326 
327 #else
328 static void register_nodes(void)
329 {
330 	return;
331 }
332 
333 #endif
334 
335 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
336 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
337 
338 /* Only valid if CPU is present. */
339 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
340 {
341 	struct cpu *cpu = container_of(dev, struct cpu, sysdev);
342 
343 	return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
344 }
345 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
346 
347 static int __init topology_init(void)
348 {
349 	int cpu;
350 
351 	register_nodes();
352 	register_cpu_notifier(&sysfs_cpu_nb);
353 
354 	for_each_possible_cpu(cpu) {
355 		struct cpu *c = &per_cpu(cpu_devices, cpu);
356 
357 		/*
358 		 * For now, we just see if the system supports making
359 		 * the RTAS calls for CPU hotplug.  But, there may be a
360 		 * more comprehensive way to do this for an individual
361 		 * CPU.  For instance, the boot cpu might never be valid
362 		 * for hotplugging.
363 		 */
364 		if (!ppc_md.cpu_die)
365 			c->no_control = 1;
366 
367 		if (cpu_online(cpu) || (c->no_control == 0)) {
368 			register_cpu(c, cpu);
369 
370 			sysdev_create_file(&c->sysdev, &attr_physical_id);
371 		}
372 
373 		if (cpu_online(cpu))
374 			register_cpu_online(cpu);
375 	}
376 
377 	return 0;
378 }
379 __initcall(topology_init);
380