1 /*
2  * Low-level SPU handling
3  *
4  * (C) Copyright IBM Deutschland Entwicklung GmbH 2005
5  *
6  * Author: Arnd Bergmann <arndb@de.ibm.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2, or (at your option)
11  * any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21  */
22 
23 #undef DEBUG
24 
25 #include <linux/interrupt.h>
26 #include <linux/list.h>
27 #include <linux/module.h>
28 #include <linux/ptrace.h>
29 #include <linux/slab.h>
30 #include <linux/wait.h>
31 #include <linux/mm.h>
32 #include <linux/io.h>
33 #include <linux/mutex.h>
34 #include <linux/linux_logo.h>
35 #include <asm/spu.h>
36 #include <asm/spu_priv1.h>
37 #include <asm/spu_csa.h>
38 #include <asm/xmon.h>
39 #include <asm/prom.h>
40 
41 const struct spu_management_ops *spu_management_ops;
42 EXPORT_SYMBOL_GPL(spu_management_ops);
43 
44 const struct spu_priv1_ops *spu_priv1_ops;
45 EXPORT_SYMBOL_GPL(spu_priv1_ops);
46 
47 struct cbe_spu_info cbe_spu_info[MAX_NUMNODES];
48 EXPORT_SYMBOL_GPL(cbe_spu_info);
49 
50 /*
51  * The spufs fault-handling code needs to call force_sig_info to raise signals
52  * on DMA errors. Export it here to avoid general kernel-wide access to this
53  * function
54  */
55 EXPORT_SYMBOL_GPL(force_sig_info);
56 
57 /*
58  * Protects cbe_spu_info and spu->number.
59  */
60 static DEFINE_SPINLOCK(spu_lock);
61 
62 /*
63  * List of all spus in the system.
64  *
65  * This list is iterated by callers from irq context and callers that
66  * want to sleep.  Thus modifications need to be done with both
67  * spu_full_list_lock and spu_full_list_mutex held, while iterating
68  * through it requires either of these locks.
69  *
70  * In addition spu_full_list_lock protects all assignmens to
71  * spu->mm.
72  */
73 static LIST_HEAD(spu_full_list);
74 static DEFINE_SPINLOCK(spu_full_list_lock);
75 static DEFINE_MUTEX(spu_full_list_mutex);
76 
77 struct spu_slb {
78 	u64 esid, vsid;
79 };
80 
81 void spu_invalidate_slbs(struct spu *spu)
82 {
83 	struct spu_priv2 __iomem *priv2 = spu->priv2;
84 	unsigned long flags;
85 
86 	spin_lock_irqsave(&spu->register_lock, flags);
87 	if (spu_mfc_sr1_get(spu) & MFC_STATE1_RELOCATE_MASK)
88 		out_be64(&priv2->slb_invalidate_all_W, 0UL);
89 	spin_unlock_irqrestore(&spu->register_lock, flags);
90 }
91 EXPORT_SYMBOL_GPL(spu_invalidate_slbs);
92 
93 /* This is called by the MM core when a segment size is changed, to
94  * request a flush of all the SPEs using a given mm
95  */
96 void spu_flush_all_slbs(struct mm_struct *mm)
97 {
98 	struct spu *spu;
99 	unsigned long flags;
100 
101 	spin_lock_irqsave(&spu_full_list_lock, flags);
102 	list_for_each_entry(spu, &spu_full_list, full_list) {
103 		if (spu->mm == mm)
104 			spu_invalidate_slbs(spu);
105 	}
106 	spin_unlock_irqrestore(&spu_full_list_lock, flags);
107 }
108 
109 /* The hack below stinks... try to do something better one of
110  * these days... Does it even work properly with NR_CPUS == 1 ?
111  */
112 static inline void mm_needs_global_tlbie(struct mm_struct *mm)
113 {
114 	int nr = (NR_CPUS > 1) ? NR_CPUS : NR_CPUS + 1;
115 
116 	/* Global TLBIE broadcast required with SPEs. */
117 	__cpus_setall(&mm->cpu_vm_mask, nr);
118 }
119 
120 void spu_associate_mm(struct spu *spu, struct mm_struct *mm)
121 {
122 	unsigned long flags;
123 
124 	spin_lock_irqsave(&spu_full_list_lock, flags);
125 	spu->mm = mm;
126 	spin_unlock_irqrestore(&spu_full_list_lock, flags);
127 	if (mm)
128 		mm_needs_global_tlbie(mm);
129 }
130 EXPORT_SYMBOL_GPL(spu_associate_mm);
131 
132 int spu_64k_pages_available(void)
133 {
134 	return mmu_psize_defs[MMU_PAGE_64K].shift != 0;
135 }
136 EXPORT_SYMBOL_GPL(spu_64k_pages_available);
137 
138 static void spu_restart_dma(struct spu *spu)
139 {
140 	struct spu_priv2 __iomem *priv2 = spu->priv2;
141 
142 	if (!test_bit(SPU_CONTEXT_SWITCH_PENDING, &spu->flags))
143 		out_be64(&priv2->mfc_control_RW, MFC_CNTL_RESTART_DMA_COMMAND);
144 }
145 
146 static inline void spu_load_slb(struct spu *spu, int slbe, struct spu_slb *slb)
147 {
148 	struct spu_priv2 __iomem *priv2 = spu->priv2;
149 
150 	pr_debug("%s: adding SLB[%d] 0x%016lx 0x%016lx\n",
151 			__func__, slbe, slb->vsid, slb->esid);
152 
153 	out_be64(&priv2->slb_index_W, slbe);
154 	/* set invalid before writing vsid */
155 	out_be64(&priv2->slb_esid_RW, 0);
156 	/* now it's safe to write the vsid */
157 	out_be64(&priv2->slb_vsid_RW, slb->vsid);
158 	/* setting the new esid makes the entry valid again */
159 	out_be64(&priv2->slb_esid_RW, slb->esid);
160 }
161 
162 static int __spu_trap_data_seg(struct spu *spu, unsigned long ea)
163 {
164 	struct mm_struct *mm = spu->mm;
165 	struct spu_slb slb;
166 	int psize;
167 
168 	pr_debug("%s\n", __FUNCTION__);
169 
170 	slb.esid = (ea & ESID_MASK) | SLB_ESID_V;
171 
172 	switch(REGION_ID(ea)) {
173 	case USER_REGION_ID:
174 #ifdef CONFIG_PPC_MM_SLICES
175 		psize = get_slice_psize(mm, ea);
176 #else
177 		psize = mm->context.user_psize;
178 #endif
179 		slb.vsid = (get_vsid(mm->context.id, ea, MMU_SEGSIZE_256M)
180 				<< SLB_VSID_SHIFT) | SLB_VSID_USER;
181 		break;
182 	case VMALLOC_REGION_ID:
183 		if (ea < VMALLOC_END)
184 			psize = mmu_vmalloc_psize;
185 		else
186 			psize = mmu_io_psize;
187 		slb.vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M)
188 				<< SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
189 		break;
190 	case KERNEL_REGION_ID:
191 		psize = mmu_linear_psize;
192 		slb.vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M)
193 				<< SLB_VSID_SHIFT) | SLB_VSID_KERNEL;
194 		break;
195 	default:
196 		/* Future: support kernel segments so that drivers
197 		 * can use SPUs.
198 		 */
199 		pr_debug("invalid region access at %016lx\n", ea);
200 		return 1;
201 	}
202 	slb.vsid |= mmu_psize_defs[psize].sllp;
203 
204 	spu_load_slb(spu, spu->slb_replace, &slb);
205 
206 	spu->slb_replace++;
207 	if (spu->slb_replace >= 8)
208 		spu->slb_replace = 0;
209 
210 	spu_restart_dma(spu);
211 	spu->stats.slb_flt++;
212 	return 0;
213 }
214 
215 extern int hash_page(unsigned long ea, unsigned long access, unsigned long trap); //XXX
216 static int __spu_trap_data_map(struct spu *spu, unsigned long ea, u64 dsisr)
217 {
218 	pr_debug("%s, %lx, %lx\n", __FUNCTION__, dsisr, ea);
219 
220 	/* Handle kernel space hash faults immediately.
221 	   User hash faults need to be deferred to process context. */
222 	if ((dsisr & MFC_DSISR_PTE_NOT_FOUND)
223 	    && REGION_ID(ea) != USER_REGION_ID
224 	    && hash_page(ea, _PAGE_PRESENT, 0x300) == 0) {
225 		spu_restart_dma(spu);
226 		return 0;
227 	}
228 
229 	spu->class_0_pending = 0;
230 	spu->dar = ea;
231 	spu->dsisr = dsisr;
232 
233 	spu->stop_callback(spu);
234 
235 	return 0;
236 }
237 
238 static void __spu_kernel_slb(void *addr, struct spu_slb *slb)
239 {
240 	unsigned long ea = (unsigned long)addr;
241 	u64 llp;
242 
243 	if (REGION_ID(ea) == KERNEL_REGION_ID)
244 		llp = mmu_psize_defs[mmu_linear_psize].sllp;
245 	else
246 		llp = mmu_psize_defs[mmu_virtual_psize].sllp;
247 
248 	slb->vsid = (get_kernel_vsid(ea, MMU_SEGSIZE_256M) << SLB_VSID_SHIFT) |
249 		SLB_VSID_KERNEL | llp;
250 	slb->esid = (ea & ESID_MASK) | SLB_ESID_V;
251 }
252 
253 /**
254  * Given an array of @nr_slbs SLB entries, @slbs, return non-zero if the
255  * address @new_addr is present.
256  */
257 static inline int __slb_present(struct spu_slb *slbs, int nr_slbs,
258 		void *new_addr)
259 {
260 	unsigned long ea = (unsigned long)new_addr;
261 	int i;
262 
263 	for (i = 0; i < nr_slbs; i++)
264 		if (!((slbs[i].esid ^ ea) & ESID_MASK))
265 			return 1;
266 
267 	return 0;
268 }
269 
270 /**
271  * Setup the SPU kernel SLBs, in preparation for a context save/restore. We
272  * need to map both the context save area, and the save/restore code.
273  *
274  * Because the lscsa and code may cross segment boundaires, we check to see
275  * if mappings are required for the start and end of each range. We currently
276  * assume that the mappings are smaller that one segment - if not, something
277  * is seriously wrong.
278  */
279 void spu_setup_kernel_slbs(struct spu *spu, struct spu_lscsa *lscsa,
280 		void *code, int code_size)
281 {
282 	struct spu_slb slbs[4];
283 	int i, nr_slbs = 0;
284 	/* start and end addresses of both mappings */
285 	void *addrs[] = {
286 		lscsa, (void *)lscsa + sizeof(*lscsa) - 1,
287 		code, code + code_size - 1
288 	};
289 
290 	/* check the set of addresses, and create a new entry in the slbs array
291 	 * if there isn't already a SLB for that address */
292 	for (i = 0; i < ARRAY_SIZE(addrs); i++) {
293 		if (__slb_present(slbs, nr_slbs, addrs[i]))
294 			continue;
295 
296 		__spu_kernel_slb(addrs[i], &slbs[nr_slbs]);
297 		nr_slbs++;
298 	}
299 
300 	spin_lock_irq(&spu->register_lock);
301 	/* Add the set of SLBs */
302 	for (i = 0; i < nr_slbs; i++)
303 		spu_load_slb(spu, i, &slbs[i]);
304 	spin_unlock_irq(&spu->register_lock);
305 }
306 EXPORT_SYMBOL_GPL(spu_setup_kernel_slbs);
307 
308 static irqreturn_t
309 spu_irq_class_0(int irq, void *data)
310 {
311 	struct spu *spu;
312 	unsigned long stat, mask;
313 
314 	spu = data;
315 
316 	spin_lock(&spu->register_lock);
317 	mask = spu_int_mask_get(spu, 0);
318 	stat = spu_int_stat_get(spu, 0) & mask;
319 
320 	spu->class_0_pending |= stat;
321 	spu->dsisr = spu_mfc_dsisr_get(spu);
322 	spu->dar = spu_mfc_dar_get(spu);
323 	spin_unlock(&spu->register_lock);
324 
325 	spu->stop_callback(spu);
326 
327 	spu_int_stat_clear(spu, 0, stat);
328 
329 	return IRQ_HANDLED;
330 }
331 
332 static irqreturn_t
333 spu_irq_class_1(int irq, void *data)
334 {
335 	struct spu *spu;
336 	unsigned long stat, mask, dar, dsisr;
337 
338 	spu = data;
339 
340 	/* atomically read & clear class1 status. */
341 	spin_lock(&spu->register_lock);
342 	mask  = spu_int_mask_get(spu, 1);
343 	stat  = spu_int_stat_get(spu, 1) & mask;
344 	dar   = spu_mfc_dar_get(spu);
345 	dsisr = spu_mfc_dsisr_get(spu);
346 	if (stat & CLASS1_STORAGE_FAULT_INTR)
347 		spu_mfc_dsisr_set(spu, 0ul);
348 	spu_int_stat_clear(spu, 1, stat);
349 
350 	if (stat & CLASS1_SEGMENT_FAULT_INTR)
351 		__spu_trap_data_seg(spu, dar);
352 
353 	spin_unlock(&spu->register_lock);
354 	pr_debug("%s: %lx %lx %lx %lx\n", __FUNCTION__, mask, stat,
355 			dar, dsisr);
356 
357 	if (stat & CLASS1_STORAGE_FAULT_INTR)
358 		__spu_trap_data_map(spu, dar, dsisr);
359 
360 	if (stat & CLASS1_LS_COMPARE_SUSPEND_ON_GET_INTR)
361 		;
362 
363 	if (stat & CLASS1_LS_COMPARE_SUSPEND_ON_PUT_INTR)
364 		;
365 
366 	return stat ? IRQ_HANDLED : IRQ_NONE;
367 }
368 
369 static irqreturn_t
370 spu_irq_class_2(int irq, void *data)
371 {
372 	struct spu *spu;
373 	unsigned long stat;
374 	unsigned long mask;
375 	const int mailbox_intrs =
376 		CLASS2_MAILBOX_THRESHOLD_INTR | CLASS2_MAILBOX_INTR;
377 
378 	spu = data;
379 	spin_lock(&spu->register_lock);
380 	stat = spu_int_stat_get(spu, 2);
381 	mask = spu_int_mask_get(spu, 2);
382 	/* ignore interrupts we're not waiting for */
383 	stat &= mask;
384 
385 	/* mailbox interrupts are level triggered. mask them now before
386 	 * acknowledging */
387 	if (stat & mailbox_intrs)
388 		spu_int_mask_and(spu, 2, ~(stat & mailbox_intrs));
389 	/* acknowledge all interrupts before the callbacks */
390 	spu_int_stat_clear(spu, 2, stat);
391 	spin_unlock(&spu->register_lock);
392 
393 	pr_debug("class 2 interrupt %d, %lx, %lx\n", irq, stat, mask);
394 
395 	if (stat & CLASS2_MAILBOX_INTR)
396 		spu->ibox_callback(spu);
397 
398 	if (stat & CLASS2_SPU_STOP_INTR)
399 		spu->stop_callback(spu);
400 
401 	if (stat & CLASS2_SPU_HALT_INTR)
402 		spu->stop_callback(spu);
403 
404 	if (stat & CLASS2_SPU_DMA_TAG_GROUP_COMPLETE_INTR)
405 		spu->mfc_callback(spu);
406 
407 	if (stat & CLASS2_MAILBOX_THRESHOLD_INTR)
408 		spu->wbox_callback(spu);
409 
410 	spu->stats.class2_intr++;
411 	return stat ? IRQ_HANDLED : IRQ_NONE;
412 }
413 
414 static int spu_request_irqs(struct spu *spu)
415 {
416 	int ret = 0;
417 
418 	if (spu->irqs[0] != NO_IRQ) {
419 		snprintf(spu->irq_c0, sizeof (spu->irq_c0), "spe%02d.0",
420 			 spu->number);
421 		ret = request_irq(spu->irqs[0], spu_irq_class_0,
422 				  IRQF_DISABLED,
423 				  spu->irq_c0, spu);
424 		if (ret)
425 			goto bail0;
426 	}
427 	if (spu->irqs[1] != NO_IRQ) {
428 		snprintf(spu->irq_c1, sizeof (spu->irq_c1), "spe%02d.1",
429 			 spu->number);
430 		ret = request_irq(spu->irqs[1], spu_irq_class_1,
431 				  IRQF_DISABLED,
432 				  spu->irq_c1, spu);
433 		if (ret)
434 			goto bail1;
435 	}
436 	if (spu->irqs[2] != NO_IRQ) {
437 		snprintf(spu->irq_c2, sizeof (spu->irq_c2), "spe%02d.2",
438 			 spu->number);
439 		ret = request_irq(spu->irqs[2], spu_irq_class_2,
440 				  IRQF_DISABLED,
441 				  spu->irq_c2, spu);
442 		if (ret)
443 			goto bail2;
444 	}
445 	return 0;
446 
447 bail2:
448 	if (spu->irqs[1] != NO_IRQ)
449 		free_irq(spu->irqs[1], spu);
450 bail1:
451 	if (spu->irqs[0] != NO_IRQ)
452 		free_irq(spu->irqs[0], spu);
453 bail0:
454 	return ret;
455 }
456 
457 static void spu_free_irqs(struct spu *spu)
458 {
459 	if (spu->irqs[0] != NO_IRQ)
460 		free_irq(spu->irqs[0], spu);
461 	if (spu->irqs[1] != NO_IRQ)
462 		free_irq(spu->irqs[1], spu);
463 	if (spu->irqs[2] != NO_IRQ)
464 		free_irq(spu->irqs[2], spu);
465 }
466 
467 void spu_init_channels(struct spu *spu)
468 {
469 	static const struct {
470 		 unsigned channel;
471 		 unsigned count;
472 	} zero_list[] = {
473 		{ 0x00, 1, }, { 0x01, 1, }, { 0x03, 1, }, { 0x04, 1, },
474 		{ 0x18, 1, }, { 0x19, 1, }, { 0x1b, 1, }, { 0x1d, 1, },
475 	}, count_list[] = {
476 		{ 0x00, 0, }, { 0x03, 0, }, { 0x04, 0, }, { 0x15, 16, },
477 		{ 0x17, 1, }, { 0x18, 0, }, { 0x19, 0, }, { 0x1b, 0, },
478 		{ 0x1c, 1, }, { 0x1d, 0, }, { 0x1e, 1, },
479 	};
480 	struct spu_priv2 __iomem *priv2;
481 	int i;
482 
483 	priv2 = spu->priv2;
484 
485 	/* initialize all channel data to zero */
486 	for (i = 0; i < ARRAY_SIZE(zero_list); i++) {
487 		int count;
488 
489 		out_be64(&priv2->spu_chnlcntptr_RW, zero_list[i].channel);
490 		for (count = 0; count < zero_list[i].count; count++)
491 			out_be64(&priv2->spu_chnldata_RW, 0);
492 	}
493 
494 	/* initialize channel counts to meaningful values */
495 	for (i = 0; i < ARRAY_SIZE(count_list); i++) {
496 		out_be64(&priv2->spu_chnlcntptr_RW, count_list[i].channel);
497 		out_be64(&priv2->spu_chnlcnt_RW, count_list[i].count);
498 	}
499 }
500 EXPORT_SYMBOL_GPL(spu_init_channels);
501 
502 static int spu_shutdown(struct sys_device *sysdev)
503 {
504 	struct spu *spu = container_of(sysdev, struct spu, sysdev);
505 
506 	spu_free_irqs(spu);
507 	spu_destroy_spu(spu);
508 	return 0;
509 }
510 
511 static struct sysdev_class spu_sysdev_class = {
512 	.name = "spu",
513 	.shutdown = spu_shutdown,
514 };
515 
516 int spu_add_sysdev_attr(struct sysdev_attribute *attr)
517 {
518 	struct spu *spu;
519 
520 	mutex_lock(&spu_full_list_mutex);
521 	list_for_each_entry(spu, &spu_full_list, full_list)
522 		sysdev_create_file(&spu->sysdev, attr);
523 	mutex_unlock(&spu_full_list_mutex);
524 
525 	return 0;
526 }
527 EXPORT_SYMBOL_GPL(spu_add_sysdev_attr);
528 
529 int spu_add_sysdev_attr_group(struct attribute_group *attrs)
530 {
531 	struct spu *spu;
532 	int rc = 0;
533 
534 	mutex_lock(&spu_full_list_mutex);
535 	list_for_each_entry(spu, &spu_full_list, full_list) {
536 		rc = sysfs_create_group(&spu->sysdev.kobj, attrs);
537 
538 		/* we're in trouble here, but try unwinding anyway */
539 		if (rc) {
540 			printk(KERN_ERR "%s: can't create sysfs group '%s'\n",
541 					__func__, attrs->name);
542 
543 			list_for_each_entry_continue_reverse(spu,
544 					&spu_full_list, full_list)
545 				sysfs_remove_group(&spu->sysdev.kobj, attrs);
546 			break;
547 		}
548 	}
549 
550 	mutex_unlock(&spu_full_list_mutex);
551 
552 	return rc;
553 }
554 EXPORT_SYMBOL_GPL(spu_add_sysdev_attr_group);
555 
556 
557 void spu_remove_sysdev_attr(struct sysdev_attribute *attr)
558 {
559 	struct spu *spu;
560 
561 	mutex_lock(&spu_full_list_mutex);
562 	list_for_each_entry(spu, &spu_full_list, full_list)
563 		sysdev_remove_file(&spu->sysdev, attr);
564 	mutex_unlock(&spu_full_list_mutex);
565 }
566 EXPORT_SYMBOL_GPL(spu_remove_sysdev_attr);
567 
568 void spu_remove_sysdev_attr_group(struct attribute_group *attrs)
569 {
570 	struct spu *spu;
571 
572 	mutex_lock(&spu_full_list_mutex);
573 	list_for_each_entry(spu, &spu_full_list, full_list)
574 		sysfs_remove_group(&spu->sysdev.kobj, attrs);
575 	mutex_unlock(&spu_full_list_mutex);
576 }
577 EXPORT_SYMBOL_GPL(spu_remove_sysdev_attr_group);
578 
579 static int spu_create_sysdev(struct spu *spu)
580 {
581 	int ret;
582 
583 	spu->sysdev.id = spu->number;
584 	spu->sysdev.cls = &spu_sysdev_class;
585 	ret = sysdev_register(&spu->sysdev);
586 	if (ret) {
587 		printk(KERN_ERR "Can't register SPU %d with sysfs\n",
588 				spu->number);
589 		return ret;
590 	}
591 
592 	sysfs_add_device_to_node(&spu->sysdev, spu->node);
593 
594 	return 0;
595 }
596 
597 static int __init create_spu(void *data)
598 {
599 	struct spu *spu;
600 	int ret;
601 	static int number;
602 	unsigned long flags;
603 	struct timespec ts;
604 
605 	ret = -ENOMEM;
606 	spu = kzalloc(sizeof (*spu), GFP_KERNEL);
607 	if (!spu)
608 		goto out;
609 
610 	spu->alloc_state = SPU_FREE;
611 
612 	spin_lock_init(&spu->register_lock);
613 	spin_lock(&spu_lock);
614 	spu->number = number++;
615 	spin_unlock(&spu_lock);
616 
617 	ret = spu_create_spu(spu, data);
618 
619 	if (ret)
620 		goto out_free;
621 
622 	spu_mfc_sdr_setup(spu);
623 	spu_mfc_sr1_set(spu, 0x33);
624 	ret = spu_request_irqs(spu);
625 	if (ret)
626 		goto out_destroy;
627 
628 	ret = spu_create_sysdev(spu);
629 	if (ret)
630 		goto out_free_irqs;
631 
632 	mutex_lock(&cbe_spu_info[spu->node].list_mutex);
633 	list_add(&spu->cbe_list, &cbe_spu_info[spu->node].spus);
634 	cbe_spu_info[spu->node].n_spus++;
635 	mutex_unlock(&cbe_spu_info[spu->node].list_mutex);
636 
637 	mutex_lock(&spu_full_list_mutex);
638 	spin_lock_irqsave(&spu_full_list_lock, flags);
639 	list_add(&spu->full_list, &spu_full_list);
640 	spin_unlock_irqrestore(&spu_full_list_lock, flags);
641 	mutex_unlock(&spu_full_list_mutex);
642 
643 	spu->stats.util_state = SPU_UTIL_IDLE_LOADED;
644 	ktime_get_ts(&ts);
645 	spu->stats.tstamp = timespec_to_ns(&ts);
646 
647 	INIT_LIST_HEAD(&spu->aff_list);
648 
649 	goto out;
650 
651 out_free_irqs:
652 	spu_free_irqs(spu);
653 out_destroy:
654 	spu_destroy_spu(spu);
655 out_free:
656 	kfree(spu);
657 out:
658 	return ret;
659 }
660 
661 static const char *spu_state_names[] = {
662 	"user", "system", "iowait", "idle"
663 };
664 
665 static unsigned long long spu_acct_time(struct spu *spu,
666 		enum spu_utilization_state state)
667 {
668 	struct timespec ts;
669 	unsigned long long time = spu->stats.times[state];
670 
671 	/*
672 	 * If the spu is idle or the context is stopped, utilization
673 	 * statistics are not updated.  Apply the time delta from the
674 	 * last recorded state of the spu.
675 	 */
676 	if (spu->stats.util_state == state) {
677 		ktime_get_ts(&ts);
678 		time += timespec_to_ns(&ts) - spu->stats.tstamp;
679 	}
680 
681 	return time / NSEC_PER_MSEC;
682 }
683 
684 
685 static ssize_t spu_stat_show(struct sys_device *sysdev, char *buf)
686 {
687 	struct spu *spu = container_of(sysdev, struct spu, sysdev);
688 
689 	return sprintf(buf, "%s %llu %llu %llu %llu "
690 		      "%llu %llu %llu %llu %llu %llu %llu %llu\n",
691 		spu_state_names[spu->stats.util_state],
692 		spu_acct_time(spu, SPU_UTIL_USER),
693 		spu_acct_time(spu, SPU_UTIL_SYSTEM),
694 		spu_acct_time(spu, SPU_UTIL_IOWAIT),
695 		spu_acct_time(spu, SPU_UTIL_IDLE_LOADED),
696 		spu->stats.vol_ctx_switch,
697 		spu->stats.invol_ctx_switch,
698 		spu->stats.slb_flt,
699 		spu->stats.hash_flt,
700 		spu->stats.min_flt,
701 		spu->stats.maj_flt,
702 		spu->stats.class2_intr,
703 		spu->stats.libassist);
704 }
705 
706 static SYSDEV_ATTR(stat, 0644, spu_stat_show, NULL);
707 
708 static int __init init_spu_base(void)
709 {
710 	int i, ret = 0;
711 
712 	for (i = 0; i < MAX_NUMNODES; i++) {
713 		mutex_init(&cbe_spu_info[i].list_mutex);
714 		INIT_LIST_HEAD(&cbe_spu_info[i].spus);
715 	}
716 
717 	if (!spu_management_ops)
718 		goto out;
719 
720 	/* create sysdev class for spus */
721 	ret = sysdev_class_register(&spu_sysdev_class);
722 	if (ret)
723 		goto out;
724 
725 	ret = spu_enumerate_spus(create_spu);
726 
727 	if (ret < 0) {
728 		printk(KERN_WARNING "%s: Error initializing spus\n",
729 			__FUNCTION__);
730 		goto out_unregister_sysdev_class;
731 	}
732 
733 	if (ret > 0) {
734 		/*
735 		 * We cannot put the forward declaration in
736 		 * <linux/linux_logo.h> because of conflicting session type
737 		 * conflicts for const and __initdata with different compiler
738 		 * versions
739 		 */
740 		extern const struct linux_logo logo_spe_clut224;
741 
742 		fb_append_extra_logo(&logo_spe_clut224, ret);
743 	}
744 
745 	mutex_lock(&spu_full_list_mutex);
746 	xmon_register_spus(&spu_full_list);
747 	crash_register_spus(&spu_full_list);
748 	mutex_unlock(&spu_full_list_mutex);
749 	spu_add_sysdev_attr(&attr_stat);
750 
751 	spu_init_affinity();
752 
753 	return 0;
754 
755  out_unregister_sysdev_class:
756 	sysdev_class_unregister(&spu_sysdev_class);
757  out:
758 	return ret;
759 }
760 module_init(init_spu_base);
761 
762 MODULE_LICENSE("GPL");
763 MODULE_AUTHOR("Arnd Bergmann <arndb@de.ibm.com>");
764