xref: /linux/arch/s390/pci/pci.c (revision b889fcf63cb62e7fdb7816565e28f44dbe4a76a5)
1 /*
2  * Copyright IBM Corp. 2012
3  *
4  * Author(s):
5  *   Jan Glauber <jang@linux.vnet.ibm.com>
6  *
7  * The System z PCI code is a rewrite from a prototype by
8  * the following people (Kudoz!):
9  *   Alexander Schmidt
10  *   Christoph Raisch
11  *   Hannes Hering
12  *   Hoang-Nam Nguyen
13  *   Jan-Bernd Themann
14  *   Stefan Roscher
15  *   Thomas Klein
16  */
17 
18 #define COMPONENT "zPCI"
19 #define pr_fmt(fmt) COMPONENT ": " fmt
20 
21 #include <linux/kernel.h>
22 #include <linux/slab.h>
23 #include <linux/err.h>
24 #include <linux/export.h>
25 #include <linux/delay.h>
26 #include <linux/irq.h>
27 #include <linux/kernel_stat.h>
28 #include <linux/seq_file.h>
29 #include <linux/pci.h>
30 #include <linux/msi.h>
31 
32 #include <asm/isc.h>
33 #include <asm/airq.h>
34 #include <asm/facility.h>
35 #include <asm/pci_insn.h>
36 #include <asm/pci_clp.h>
37 #include <asm/pci_dma.h>
38 
39 #define DEBUG				/* enable pr_debug */
40 
41 #define	SIC_IRQ_MODE_ALL		0
42 #define	SIC_IRQ_MODE_SINGLE		1
43 
44 #define ZPCI_NR_DMA_SPACES		1
45 #define ZPCI_MSI_VEC_BITS		6
46 #define ZPCI_NR_DEVICES			CONFIG_PCI_NR_FUNCTIONS
47 
48 /* list of all detected zpci devices */
49 LIST_HEAD(zpci_list);
50 EXPORT_SYMBOL_GPL(zpci_list);
51 DEFINE_MUTEX(zpci_list_lock);
52 EXPORT_SYMBOL_GPL(zpci_list_lock);
53 
54 struct pci_hp_callback_ops hotplug_ops;
55 EXPORT_SYMBOL_GPL(hotplug_ops);
56 
57 static DECLARE_BITMAP(zpci_domain, ZPCI_NR_DEVICES);
58 static DEFINE_SPINLOCK(zpci_domain_lock);
59 
60 struct callback {
61 	irq_handler_t	handler;
62 	void		*data;
63 };
64 
65 struct zdev_irq_map {
66 	unsigned long	aibv;		/* AI bit vector */
67 	int		msi_vecs;	/* consecutive MSI-vectors used */
68 	int		__unused;
69 	struct callback	cb[ZPCI_NR_MSI_VECS]; /* callback handler array */
70 	spinlock_t	lock;		/* protect callbacks against de-reg */
71 };
72 
73 struct intr_bucket {
74 	/* amap of adapters, one bit per dev, corresponds to one irq nr */
75 	unsigned long	*alloc;
76 	/* AI summary bit, global page for all devices */
77 	unsigned long	*aisb;
78 	/* pointer to aibv and callback data in zdev */
79 	struct zdev_irq_map *imap[ZPCI_NR_DEVICES];
80 	/* protects the whole bucket struct */
81 	spinlock_t	lock;
82 };
83 
84 static struct intr_bucket *bucket;
85 
86 /* Adapter local summary indicator */
87 static u8 *zpci_irq_si;
88 
89 static atomic_t irq_retries = ATOMIC_INIT(0);
90 
91 /* I/O Map */
92 static DEFINE_SPINLOCK(zpci_iomap_lock);
93 static DECLARE_BITMAP(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
94 struct zpci_iomap_entry *zpci_iomap_start;
95 EXPORT_SYMBOL_GPL(zpci_iomap_start);
96 
97 /* highest irq summary bit */
98 static int __read_mostly aisb_max;
99 
100 static struct kmem_cache *zdev_irq_cache;
101 static struct kmem_cache *zdev_fmb_cache;
102 
103 debug_info_t *pci_debug_msg_id;
104 debug_info_t *pci_debug_err_id;
105 
106 static inline int irq_to_msi_nr(unsigned int irq)
107 {
108 	return irq & ZPCI_MSI_MASK;
109 }
110 
111 static inline int irq_to_dev_nr(unsigned int irq)
112 {
113 	return irq >> ZPCI_MSI_VEC_BITS;
114 }
115 
116 static inline struct zdev_irq_map *get_imap(unsigned int irq)
117 {
118 	return bucket->imap[irq_to_dev_nr(irq)];
119 }
120 
121 struct zpci_dev *get_zdev(struct pci_dev *pdev)
122 {
123 	return (struct zpci_dev *) pdev->sysdata;
124 }
125 
126 struct zpci_dev *get_zdev_by_fid(u32 fid)
127 {
128 	struct zpci_dev *tmp, *zdev = NULL;
129 
130 	mutex_lock(&zpci_list_lock);
131 	list_for_each_entry(tmp, &zpci_list, entry) {
132 		if (tmp->fid == fid) {
133 			zdev = tmp;
134 			break;
135 		}
136 	}
137 	mutex_unlock(&zpci_list_lock);
138 	return zdev;
139 }
140 
141 bool zpci_fid_present(u32 fid)
142 {
143 	return (get_zdev_by_fid(fid) != NULL) ? true : false;
144 }
145 
146 static struct zpci_dev *get_zdev_by_bus(struct pci_bus *bus)
147 {
148 	return (bus && bus->sysdata) ? (struct zpci_dev *) bus->sysdata : NULL;
149 }
150 
151 int pci_domain_nr(struct pci_bus *bus)
152 {
153 	return ((struct zpci_dev *) bus->sysdata)->domain;
154 }
155 EXPORT_SYMBOL_GPL(pci_domain_nr);
156 
157 int pci_proc_domain(struct pci_bus *bus)
158 {
159 	return pci_domain_nr(bus);
160 }
161 EXPORT_SYMBOL_GPL(pci_proc_domain);
162 
163 /* Store PCI function information block */
164 static int zpci_store_fib(struct zpci_dev *zdev, u8 *fc)
165 {
166 	struct zpci_fib *fib;
167 	u8 status, cc;
168 
169 	fib = (void *) get_zeroed_page(GFP_KERNEL);
170 	if (!fib)
171 		return -ENOMEM;
172 
173 	do {
174 		cc = __stpcifc(zdev->fh, 0, fib, &status);
175 		if (cc == 2) {
176 			msleep(ZPCI_INSN_BUSY_DELAY);
177 			memset(fib, 0, PAGE_SIZE);
178 		}
179 	} while (cc == 2);
180 
181 	if (cc)
182 		pr_err_once("%s: cc: %u  status: %u\n",
183 			    __func__, cc, status);
184 
185 	/* Return PCI function controls */
186 	*fc = fib->fc;
187 
188 	free_page((unsigned long) fib);
189 	return (cc) ? -EIO : 0;
190 }
191 
192 /* Modify PCI: Register adapter interruptions */
193 static int zpci_register_airq(struct zpci_dev *zdev, unsigned int aisb,
194 			      u64 aibv)
195 {
196 	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_REG_INT);
197 	struct zpci_fib *fib;
198 	int rc;
199 
200 	fib = (void *) get_zeroed_page(GFP_KERNEL);
201 	if (!fib)
202 		return -ENOMEM;
203 
204 	fib->isc = PCI_ISC;
205 	fib->noi = zdev->irq_map->msi_vecs;
206 	fib->sum = 1;		/* enable summary notifications */
207 	fib->aibv = aibv;
208 	fib->aibvo = 0;		/* every function has its own page */
209 	fib->aisb = (u64) bucket->aisb + aisb / 8;
210 	fib->aisbo = aisb & ZPCI_MSI_MASK;
211 
212 	rc = mpcifc_instr(req, fib);
213 	pr_debug("%s mpcifc returned noi: %d\n", __func__, fib->noi);
214 
215 	free_page((unsigned long) fib);
216 	return rc;
217 }
218 
219 struct mod_pci_args {
220 	u64 base;
221 	u64 limit;
222 	u64 iota;
223 	u64 fmb_addr;
224 };
225 
226 static int mod_pci(struct zpci_dev *zdev, int fn, u8 dmaas, struct mod_pci_args *args)
227 {
228 	u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, fn);
229 	struct zpci_fib *fib;
230 	int rc;
231 
232 	/* The FIB must be available even if it's not used */
233 	fib = (void *) get_zeroed_page(GFP_KERNEL);
234 	if (!fib)
235 		return -ENOMEM;
236 
237 	fib->pba = args->base;
238 	fib->pal = args->limit;
239 	fib->iota = args->iota;
240 	fib->fmb_addr = args->fmb_addr;
241 
242 	rc = mpcifc_instr(req, fib);
243 	free_page((unsigned long) fib);
244 	return rc;
245 }
246 
247 /* Modify PCI: Register I/O address translation parameters */
248 int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas,
249 		       u64 base, u64 limit, u64 iota)
250 {
251 	struct mod_pci_args args = { base, limit, iota, 0 };
252 
253 	WARN_ON_ONCE(iota & 0x3fff);
254 	args.iota |= ZPCI_IOTA_RTTO_FLAG;
255 	return mod_pci(zdev, ZPCI_MOD_FC_REG_IOAT, dmaas, &args);
256 }
257 
258 /* Modify PCI: Unregister I/O address translation parameters */
259 int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas)
260 {
261 	struct mod_pci_args args = { 0, 0, 0, 0 };
262 
263 	return mod_pci(zdev, ZPCI_MOD_FC_DEREG_IOAT, dmaas, &args);
264 }
265 
266 /* Modify PCI: Unregister adapter interruptions */
267 static int zpci_unregister_airq(struct zpci_dev *zdev)
268 {
269 	struct mod_pci_args args = { 0, 0, 0, 0 };
270 
271 	return mod_pci(zdev, ZPCI_MOD_FC_DEREG_INT, 0, &args);
272 }
273 
274 /* Modify PCI: Set PCI function measurement parameters */
275 int zpci_fmb_enable_device(struct zpci_dev *zdev)
276 {
277 	struct mod_pci_args args = { 0, 0, 0, 0 };
278 
279 	if (zdev->fmb)
280 		return -EINVAL;
281 
282 	zdev->fmb = kmem_cache_alloc(zdev_fmb_cache, GFP_KERNEL);
283 	if (!zdev->fmb)
284 		return -ENOMEM;
285 	memset(zdev->fmb, 0, sizeof(*zdev->fmb));
286 	WARN_ON((u64) zdev->fmb & 0xf);
287 
288 	args.fmb_addr = virt_to_phys(zdev->fmb);
289 	return mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);
290 }
291 
292 /* Modify PCI: Disable PCI function measurement */
293 int zpci_fmb_disable_device(struct zpci_dev *zdev)
294 {
295 	struct mod_pci_args args = { 0, 0, 0, 0 };
296 	int rc;
297 
298 	if (!zdev->fmb)
299 		return -EINVAL;
300 
301 	/* Function measurement is disabled if fmb address is zero */
302 	rc = mod_pci(zdev, ZPCI_MOD_FC_SET_MEASURE, 0, &args);
303 
304 	kmem_cache_free(zdev_fmb_cache, zdev->fmb);
305 	zdev->fmb = NULL;
306 	return rc;
307 }
308 
309 #define ZPCI_PCIAS_CFGSPC	15
310 
311 static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)
312 {
313 	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
314 	u64 data;
315 	int rc;
316 
317 	rc = pcilg_instr(&data, req, offset);
318 	data = data << ((8 - len) * 8);
319 	data = le64_to_cpu(data);
320 	if (!rc)
321 		*val = (u32) data;
322 	else
323 		*val = 0xffffffff;
324 	return rc;
325 }
326 
327 static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len)
328 {
329 	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
330 	u64 data = val;
331 	int rc;
332 
333 	data = cpu_to_le64(data);
334 	data = data >> ((8 - len) * 8);
335 	rc = pcistg_instr(data, req, offset);
336 	return rc;
337 }
338 
339 void synchronize_irq(unsigned int irq)
340 {
341 	/*
342 	 * Not needed, the handler is protected by a lock and IRQs that occur
343 	 * after the handler is deleted are just NOPs.
344 	 */
345 }
346 EXPORT_SYMBOL_GPL(synchronize_irq);
347 
348 void enable_irq(unsigned int irq)
349 {
350 	struct msi_desc *msi = irq_get_msi_desc(irq);
351 
352 	zpci_msi_set_mask_bits(msi, 1, 0);
353 }
354 EXPORT_SYMBOL_GPL(enable_irq);
355 
356 void disable_irq(unsigned int irq)
357 {
358 	struct msi_desc *msi = irq_get_msi_desc(irq);
359 
360 	zpci_msi_set_mask_bits(msi, 1, 1);
361 }
362 EXPORT_SYMBOL_GPL(disable_irq);
363 
364 void disable_irq_nosync(unsigned int irq)
365 {
366 	disable_irq(irq);
367 }
368 EXPORT_SYMBOL_GPL(disable_irq_nosync);
369 
370 unsigned long probe_irq_on(void)
371 {
372 	return 0;
373 }
374 EXPORT_SYMBOL_GPL(probe_irq_on);
375 
376 int probe_irq_off(unsigned long val)
377 {
378 	return 0;
379 }
380 EXPORT_SYMBOL_GPL(probe_irq_off);
381 
382 unsigned int probe_irq_mask(unsigned long val)
383 {
384 	return val;
385 }
386 EXPORT_SYMBOL_GPL(probe_irq_mask);
387 
388 void __devinit pcibios_fixup_bus(struct pci_bus *bus)
389 {
390 }
391 
392 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
393 				       resource_size_t size,
394 				       resource_size_t align)
395 {
396 	return 0;
397 }
398 
399 /* combine single writes by using store-block insn */
400 void __iowrite64_copy(void __iomem *to, const void *from, size_t count)
401 {
402        zpci_memcpy_toio(to, from, count);
403 }
404 
405 /* Create a virtual mapping cookie for a PCI BAR */
406 void __iomem *pci_iomap(struct pci_dev *pdev, int bar, unsigned long max)
407 {
408 	struct zpci_dev *zdev =	get_zdev(pdev);
409 	u64 addr;
410 	int idx;
411 
412 	if ((bar & 7) != bar)
413 		return NULL;
414 
415 	idx = zdev->bars[bar].map_idx;
416 	spin_lock(&zpci_iomap_lock);
417 	zpci_iomap_start[idx].fh = zdev->fh;
418 	zpci_iomap_start[idx].bar = bar;
419 	spin_unlock(&zpci_iomap_lock);
420 
421 	addr = ZPCI_IOMAP_ADDR_BASE | ((u64) idx << 48);
422 	return (void __iomem *) addr;
423 }
424 EXPORT_SYMBOL_GPL(pci_iomap);
425 
426 void pci_iounmap(struct pci_dev *pdev, void __iomem *addr)
427 {
428 	unsigned int idx;
429 
430 	idx = (((__force u64) addr) & ~ZPCI_IOMAP_ADDR_BASE) >> 48;
431 	spin_lock(&zpci_iomap_lock);
432 	zpci_iomap_start[idx].fh = 0;
433 	zpci_iomap_start[idx].bar = 0;
434 	spin_unlock(&zpci_iomap_lock);
435 }
436 EXPORT_SYMBOL_GPL(pci_iounmap);
437 
438 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
439 		    int size, u32 *val)
440 {
441 	struct zpci_dev *zdev = get_zdev_by_bus(bus);
442 
443 	if (!zdev || devfn != ZPCI_DEVFN)
444 		return 0;
445 	return zpci_cfg_load(zdev, where, val, size);
446 }
447 
448 static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
449 		     int size, u32 val)
450 {
451 	struct zpci_dev *zdev = get_zdev_by_bus(bus);
452 
453 	if (!zdev || devfn != ZPCI_DEVFN)
454 		return 0;
455 	return zpci_cfg_store(zdev, where, val, size);
456 }
457 
458 static struct pci_ops pci_root_ops = {
459 	.read = pci_read,
460 	.write = pci_write,
461 };
462 
463 /* store the last handled bit to implement fair scheduling of devices */
464 static DEFINE_PER_CPU(unsigned long, next_sbit);
465 
466 static void zpci_irq_handler(void *dont, void *need)
467 {
468 	unsigned long sbit, mbit, last = 0, start = __get_cpu_var(next_sbit);
469 	int rescan = 0, max = aisb_max;
470 	struct zdev_irq_map *imap;
471 
472 	kstat_cpu(smp_processor_id()).irqs[IOINT_PCI]++;
473 	sbit = start;
474 
475 scan:
476 	/* find summary_bit */
477 	for_each_set_bit_left_cont(sbit, bucket->aisb, max) {
478 		clear_bit(63 - (sbit & 63), bucket->aisb + (sbit >> 6));
479 		last = sbit;
480 
481 		/* find vector bit */
482 		imap = bucket->imap[sbit];
483 		for_each_set_bit_left(mbit, &imap->aibv, imap->msi_vecs) {
484 			kstat_cpu(smp_processor_id()).irqs[IOINT_MSI]++;
485 			clear_bit(63 - mbit, &imap->aibv);
486 
487 			spin_lock(&imap->lock);
488 			if (imap->cb[mbit].handler)
489 				imap->cb[mbit].handler(mbit,
490 					imap->cb[mbit].data);
491 			spin_unlock(&imap->lock);
492 		}
493 	}
494 
495 	if (rescan)
496 		goto out;
497 
498 	/* scan the skipped bits */
499 	if (start > 0) {
500 		sbit = 0;
501 		max = start;
502 		start = 0;
503 		goto scan;
504 	}
505 
506 	/* enable interrupts again */
507 	sic_instr(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC);
508 
509 	/* check again to not lose initiative */
510 	rmb();
511 	max = aisb_max;
512 	sbit = find_first_bit_left(bucket->aisb, max);
513 	if (sbit != max) {
514 		atomic_inc(&irq_retries);
515 		rescan++;
516 		goto scan;
517 	}
518 out:
519 	/* store next device bit to scan */
520 	__get_cpu_var(next_sbit) = (++last >= aisb_max) ? 0 : last;
521 }
522 
523 /* msi_vecs - number of requested interrupts, 0 place function to error state */
524 static int zpci_setup_msi(struct pci_dev *pdev, int msi_vecs)
525 {
526 	struct zpci_dev *zdev = get_zdev(pdev);
527 	unsigned int aisb, msi_nr;
528 	struct msi_desc *msi;
529 	int rc;
530 
531 	/* store the number of used MSI vectors */
532 	zdev->irq_map->msi_vecs = min(msi_vecs, ZPCI_NR_MSI_VECS);
533 
534 	spin_lock(&bucket->lock);
535 	aisb = find_first_zero_bit(bucket->alloc, PAGE_SIZE);
536 	/* alloc map exhausted? */
537 	if (aisb == PAGE_SIZE) {
538 		spin_unlock(&bucket->lock);
539 		return -EIO;
540 	}
541 	set_bit(aisb, bucket->alloc);
542 	spin_unlock(&bucket->lock);
543 
544 	zdev->aisb = aisb;
545 	if (aisb + 1 > aisb_max)
546 		aisb_max = aisb + 1;
547 
548 	/* wire up IRQ shortcut pointer */
549 	bucket->imap[zdev->aisb] = zdev->irq_map;
550 	pr_debug("%s: imap[%u] linked to %p\n", __func__, zdev->aisb, zdev->irq_map);
551 
552 	/* TODO: irq number 0 wont be found if we return less than requested MSIs.
553 	 * ignore it for now and fix in common code.
554 	 */
555 	msi_nr = aisb << ZPCI_MSI_VEC_BITS;
556 
557 	list_for_each_entry(msi, &pdev->msi_list, list) {
558 		rc = zpci_setup_msi_irq(zdev, msi, msi_nr,
559 					  aisb << ZPCI_MSI_VEC_BITS);
560 		if (rc)
561 			return rc;
562 		msi_nr++;
563 	}
564 
565 	rc = zpci_register_airq(zdev, aisb, (u64) &zdev->irq_map->aibv);
566 	if (rc) {
567 		clear_bit(aisb, bucket->alloc);
568 		dev_err(&pdev->dev, "register MSI failed with: %d\n", rc);
569 		return rc;
570 	}
571 	return (zdev->irq_map->msi_vecs == msi_vecs) ?
572 		0 : zdev->irq_map->msi_vecs;
573 }
574 
575 static void zpci_teardown_msi(struct pci_dev *pdev)
576 {
577 	struct zpci_dev *zdev = get_zdev(pdev);
578 	struct msi_desc *msi;
579 	int aisb, rc;
580 
581 	rc = zpci_unregister_airq(zdev);
582 	if (rc) {
583 		dev_err(&pdev->dev, "deregister MSI failed with: %d\n", rc);
584 		return;
585 	}
586 
587 	msi = list_first_entry(&pdev->msi_list, struct msi_desc, list);
588 	aisb = irq_to_dev_nr(msi->irq);
589 
590 	list_for_each_entry(msi, &pdev->msi_list, list)
591 		zpci_teardown_msi_irq(zdev, msi);
592 
593 	clear_bit(aisb, bucket->alloc);
594 	if (aisb + 1 == aisb_max)
595 		aisb_max--;
596 }
597 
598 int arch_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
599 {
600 	pr_debug("%s: requesting %d MSI-X interrupts...", __func__, nvec);
601 	if (type != PCI_CAP_ID_MSIX && type != PCI_CAP_ID_MSI)
602 		return -EINVAL;
603 	return zpci_setup_msi(pdev, nvec);
604 }
605 
606 void arch_teardown_msi_irqs(struct pci_dev *pdev)
607 {
608 	pr_info("%s: on pdev: %p\n", __func__, pdev);
609 	zpci_teardown_msi(pdev);
610 }
611 
612 static void zpci_map_resources(struct zpci_dev *zdev)
613 {
614 	struct pci_dev *pdev = zdev->pdev;
615 	resource_size_t len;
616 	int i;
617 
618 	for (i = 0; i < PCI_BAR_COUNT; i++) {
619 		len = pci_resource_len(pdev, i);
620 		if (!len)
621 			continue;
622 		pdev->resource[i].start = (resource_size_t) pci_iomap(pdev, i, 0);
623 		pdev->resource[i].end = pdev->resource[i].start + len - 1;
624 		pr_debug("BAR%i: -> start: %Lx  end: %Lx\n",
625 			i, pdev->resource[i].start, pdev->resource[i].end);
626 	}
627 };
628 
629 static void zpci_unmap_resources(struct pci_dev *pdev)
630 {
631 	resource_size_t len;
632 	int i;
633 
634 	for (i = 0; i < PCI_BAR_COUNT; i++) {
635 		len = pci_resource_len(pdev, i);
636 		if (!len)
637 			continue;
638 		pci_iounmap(pdev, (void *) pdev->resource[i].start);
639 	}
640 };
641 
642 struct zpci_dev *zpci_alloc_device(void)
643 {
644 	struct zpci_dev *zdev;
645 
646 	/* Alloc memory for our private pci device data */
647 	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
648 	if (!zdev)
649 		return ERR_PTR(-ENOMEM);
650 
651 	/* Alloc aibv & callback space */
652 	zdev->irq_map = kmem_cache_zalloc(zdev_irq_cache, GFP_KERNEL);
653 	if (!zdev->irq_map)
654 		goto error;
655 	WARN_ON((u64) zdev->irq_map & 0xff);
656 	return zdev;
657 
658 error:
659 	kfree(zdev);
660 	return ERR_PTR(-ENOMEM);
661 }
662 
663 void zpci_free_device(struct zpci_dev *zdev)
664 {
665 	kmem_cache_free(zdev_irq_cache, zdev->irq_map);
666 	kfree(zdev);
667 }
668 
669 /* Called on removal of pci_dev, leaves zpci and bus device */
670 static void zpci_remove_device(struct pci_dev *pdev)
671 {
672 	struct zpci_dev *zdev = get_zdev(pdev);
673 
674 	dev_info(&pdev->dev, "Removing device %u\n", zdev->domain);
675 	zdev->state = ZPCI_FN_STATE_CONFIGURED;
676 	zpci_dma_exit_device(zdev);
677 	zpci_fmb_disable_device(zdev);
678 	zpci_sysfs_remove_device(&pdev->dev);
679 	zpci_unmap_resources(pdev);
680 	list_del(&zdev->entry);		/* can be called from init */
681 	zdev->pdev = NULL;
682 }
683 
684 static void zpci_scan_devices(void)
685 {
686 	struct zpci_dev *zdev;
687 
688 	mutex_lock(&zpci_list_lock);
689 	list_for_each_entry(zdev, &zpci_list, entry)
690 		if (zdev->state == ZPCI_FN_STATE_CONFIGURED)
691 			zpci_scan_device(zdev);
692 	mutex_unlock(&zpci_list_lock);
693 }
694 
695 /*
696  * Too late for any s390 specific setup, since interrupts must be set up
697  * already which requires DMA setup too and the pci scan will access the
698  * config space, which only works if the function handle is enabled.
699  */
700 int pcibios_enable_device(struct pci_dev *pdev, int mask)
701 {
702 	struct resource *res;
703 	u16 cmd;
704 	int i;
705 
706 	pci_read_config_word(pdev, PCI_COMMAND, &cmd);
707 
708 	for (i = 0; i < PCI_BAR_COUNT; i++) {
709 		res = &pdev->resource[i];
710 
711 		if (res->flags & IORESOURCE_IO)
712 			return -EINVAL;
713 
714 		if (res->flags & IORESOURCE_MEM)
715 			cmd |= PCI_COMMAND_MEMORY;
716 	}
717 	pci_write_config_word(pdev, PCI_COMMAND, cmd);
718 	return 0;
719 }
720 
721 void pcibios_disable_device(struct pci_dev *pdev)
722 {
723 	zpci_remove_device(pdev);
724 	pdev->sysdata = NULL;
725 }
726 
727 int pcibios_add_platform_entries(struct pci_dev *pdev)
728 {
729 	return zpci_sysfs_add_device(&pdev->dev);
730 }
731 
732 int zpci_request_irq(unsigned int irq, irq_handler_t handler, void *data)
733 {
734 	int msi_nr = irq_to_msi_nr(irq);
735 	struct zdev_irq_map *imap;
736 	struct msi_desc *msi;
737 
738 	msi = irq_get_msi_desc(irq);
739 	if (!msi)
740 		return -EIO;
741 
742 	imap = get_imap(irq);
743 	spin_lock_init(&imap->lock);
744 
745 	pr_debug("%s: register handler for IRQ:MSI %d:%d\n", __func__, irq >> 6, msi_nr);
746 	imap->cb[msi_nr].handler = handler;
747 	imap->cb[msi_nr].data = data;
748 
749 	/*
750 	 * The generic MSI code returns with the interrupt disabled on the
751 	 * card, using the MSI mask bits. Firmware doesn't appear to unmask
752 	 * at that level, so we do it here by hand.
753 	 */
754 	zpci_msi_set_mask_bits(msi, 1, 0);
755 	return 0;
756 }
757 
758 void zpci_free_irq(unsigned int irq)
759 {
760 	struct zdev_irq_map *imap = get_imap(irq);
761 	int msi_nr = irq_to_msi_nr(irq);
762 	unsigned long flags;
763 
764 	pr_debug("%s: for irq: %d\n", __func__, irq);
765 
766 	spin_lock_irqsave(&imap->lock, flags);
767 	imap->cb[msi_nr].handler = NULL;
768 	imap->cb[msi_nr].data = NULL;
769 	spin_unlock_irqrestore(&imap->lock, flags);
770 }
771 
772 int request_irq(unsigned int irq, irq_handler_t handler,
773 		unsigned long irqflags, const char *devname, void *dev_id)
774 {
775 	pr_debug("%s: irq: %d  handler: %p  flags: %lx  dev: %s\n",
776 		__func__, irq, handler, irqflags, devname);
777 
778 	return zpci_request_irq(irq, handler, dev_id);
779 }
780 EXPORT_SYMBOL_GPL(request_irq);
781 
782 void free_irq(unsigned int irq, void *dev_id)
783 {
784 	zpci_free_irq(irq);
785 }
786 EXPORT_SYMBOL_GPL(free_irq);
787 
788 static int __init zpci_irq_init(void)
789 {
790 	int cpu, rc;
791 
792 	bucket = kzalloc(sizeof(*bucket), GFP_KERNEL);
793 	if (!bucket)
794 		return -ENOMEM;
795 
796 	bucket->aisb = (unsigned long *) get_zeroed_page(GFP_KERNEL);
797 	if (!bucket->aisb) {
798 		rc = -ENOMEM;
799 		goto out_aisb;
800 	}
801 
802 	bucket->alloc = (unsigned long *) get_zeroed_page(GFP_KERNEL);
803 	if (!bucket->alloc) {
804 		rc = -ENOMEM;
805 		goto out_alloc;
806 	}
807 
808 	isc_register(PCI_ISC);
809 	zpci_irq_si = s390_register_adapter_interrupt(&zpci_irq_handler, NULL, PCI_ISC);
810 	if (IS_ERR(zpci_irq_si)) {
811 		rc = PTR_ERR(zpci_irq_si);
812 		zpci_irq_si = NULL;
813 		goto out_ai;
814 	}
815 
816 	for_each_online_cpu(cpu)
817 		per_cpu(next_sbit, cpu) = 0;
818 
819 	spin_lock_init(&bucket->lock);
820 	/* set summary to 1 to be called every time for the ISC */
821 	*zpci_irq_si = 1;
822 	sic_instr(SIC_IRQ_MODE_SINGLE, NULL, PCI_ISC);
823 	return 0;
824 
825 out_ai:
826 	isc_unregister(PCI_ISC);
827 	free_page((unsigned long) bucket->alloc);
828 out_alloc:
829 	free_page((unsigned long) bucket->aisb);
830 out_aisb:
831 	kfree(bucket);
832 	return rc;
833 }
834 
835 static void zpci_irq_exit(void)
836 {
837 	free_page((unsigned long) bucket->alloc);
838 	free_page((unsigned long) bucket->aisb);
839 	s390_unregister_adapter_interrupt(zpci_irq_si, PCI_ISC);
840 	isc_unregister(PCI_ISC);
841 	kfree(bucket);
842 }
843 
844 void zpci_debug_info(struct zpci_dev *zdev, struct seq_file *m)
845 {
846 	if (!zdev)
847 		return;
848 
849 	seq_printf(m, "global irq retries: %u\n", atomic_read(&irq_retries));
850 	seq_printf(m, "aibv[0]:%016lx  aibv[1]:%016lx  aisb:%016lx\n",
851 		   get_imap(0)->aibv, get_imap(1)->aibv, *bucket->aisb);
852 }
853 
854 static struct resource *zpci_alloc_bus_resource(unsigned long start, unsigned long size,
855 						unsigned long flags, int domain)
856 {
857 	struct resource *r;
858 	char *name;
859 	int rc;
860 
861 	r = kzalloc(sizeof(*r), GFP_KERNEL);
862 	if (!r)
863 		return ERR_PTR(-ENOMEM);
864 	r->start = start;
865 	r->end = r->start + size - 1;
866 	r->flags = flags;
867 	r->parent = &iomem_resource;
868 	name = kmalloc(18, GFP_KERNEL);
869 	if (!name) {
870 		kfree(r);
871 		return ERR_PTR(-ENOMEM);
872 	}
873 	sprintf(name, "PCI Bus: %04x:%02x", domain, ZPCI_BUS_NR);
874 	r->name = name;
875 
876 	rc = request_resource(&iomem_resource, r);
877 	if (rc)
878 		pr_debug("request resource %pR failed\n", r);
879 	return r;
880 }
881 
882 static int zpci_alloc_iomap(struct zpci_dev *zdev)
883 {
884 	int entry;
885 
886 	spin_lock(&zpci_iomap_lock);
887 	entry = find_first_zero_bit(zpci_iomap, ZPCI_IOMAP_MAX_ENTRIES);
888 	if (entry == ZPCI_IOMAP_MAX_ENTRIES) {
889 		spin_unlock(&zpci_iomap_lock);
890 		return -ENOSPC;
891 	}
892 	set_bit(entry, zpci_iomap);
893 	spin_unlock(&zpci_iomap_lock);
894 	return entry;
895 }
896 
897 static void zpci_free_iomap(struct zpci_dev *zdev, int entry)
898 {
899 	spin_lock(&zpci_iomap_lock);
900 	memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry));
901 	clear_bit(entry, zpci_iomap);
902 	spin_unlock(&zpci_iomap_lock);
903 }
904 
905 static int zpci_create_device_bus(struct zpci_dev *zdev)
906 {
907 	struct resource *res;
908 	LIST_HEAD(resources);
909 	int i;
910 
911 	/* allocate mapping entry for each used bar */
912 	for (i = 0; i < PCI_BAR_COUNT; i++) {
913 		unsigned long addr, size, flags;
914 		int entry;
915 
916 		if (!zdev->bars[i].size)
917 			continue;
918 		entry = zpci_alloc_iomap(zdev);
919 		if (entry < 0)
920 			return entry;
921 		zdev->bars[i].map_idx = entry;
922 
923 		/* only MMIO is supported */
924 		flags = IORESOURCE_MEM;
925 		if (zdev->bars[i].val & 8)
926 			flags |= IORESOURCE_PREFETCH;
927 		if (zdev->bars[i].val & 4)
928 			flags |= IORESOURCE_MEM_64;
929 
930 		addr = ZPCI_IOMAP_ADDR_BASE + ((u64) entry << 48);
931 
932 		size = 1UL << zdev->bars[i].size;
933 
934 		res = zpci_alloc_bus_resource(addr, size, flags, zdev->domain);
935 		if (IS_ERR(res)) {
936 			zpci_free_iomap(zdev, entry);
937 			return PTR_ERR(res);
938 		}
939 		pci_add_resource(&resources, res);
940 	}
941 
942 	zdev->bus = pci_create_root_bus(NULL, ZPCI_BUS_NR, &pci_root_ops,
943 					zdev, &resources);
944 	if (!zdev->bus)
945 		return -EIO;
946 
947 	zdev->bus->max_bus_speed = zdev->max_bus_speed;
948 	return 0;
949 }
950 
951 static int zpci_alloc_domain(struct zpci_dev *zdev)
952 {
953 	spin_lock(&zpci_domain_lock);
954 	zdev->domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES);
955 	if (zdev->domain == ZPCI_NR_DEVICES) {
956 		spin_unlock(&zpci_domain_lock);
957 		return -ENOSPC;
958 	}
959 	set_bit(zdev->domain, zpci_domain);
960 	spin_unlock(&zpci_domain_lock);
961 	return 0;
962 }
963 
964 static void zpci_free_domain(struct zpci_dev *zdev)
965 {
966 	spin_lock(&zpci_domain_lock);
967 	clear_bit(zdev->domain, zpci_domain);
968 	spin_unlock(&zpci_domain_lock);
969 }
970 
971 int zpci_enable_device(struct zpci_dev *zdev)
972 {
973 	int rc;
974 
975 	rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES);
976 	if (rc)
977 		goto out;
978 	pr_info("Enabled fh: 0x%x fid: 0x%x\n", zdev->fh, zdev->fid);
979 
980 	rc = zpci_dma_init_device(zdev);
981 	if (rc)
982 		goto out_dma;
983 	return 0;
984 
985 out_dma:
986 	clp_disable_fh(zdev);
987 out:
988 	return rc;
989 }
990 EXPORT_SYMBOL_GPL(zpci_enable_device);
991 
992 int zpci_create_device(struct zpci_dev *zdev)
993 {
994 	int rc;
995 
996 	rc = zpci_alloc_domain(zdev);
997 	if (rc)
998 		goto out;
999 
1000 	rc = zpci_create_device_bus(zdev);
1001 	if (rc)
1002 		goto out_bus;
1003 
1004 	mutex_lock(&zpci_list_lock);
1005 	list_add_tail(&zdev->entry, &zpci_list);
1006 	if (hotplug_ops.create_slot)
1007 		hotplug_ops.create_slot(zdev);
1008 	mutex_unlock(&zpci_list_lock);
1009 
1010 	if (zdev->state == ZPCI_FN_STATE_STANDBY)
1011 		return 0;
1012 
1013 	rc = zpci_enable_device(zdev);
1014 	if (rc)
1015 		goto out_start;
1016 	return 0;
1017 
1018 out_start:
1019 	mutex_lock(&zpci_list_lock);
1020 	list_del(&zdev->entry);
1021 	if (hotplug_ops.remove_slot)
1022 		hotplug_ops.remove_slot(zdev);
1023 	mutex_unlock(&zpci_list_lock);
1024 out_bus:
1025 	zpci_free_domain(zdev);
1026 out:
1027 	return rc;
1028 }
1029 
1030 void zpci_stop_device(struct zpci_dev *zdev)
1031 {
1032 	zpci_dma_exit_device(zdev);
1033 	/*
1034 	 * Note: SCLP disables fh via set-pci-fn so don't
1035 	 * do that here.
1036 	 */
1037 }
1038 EXPORT_SYMBOL_GPL(zpci_stop_device);
1039 
1040 int zpci_scan_device(struct zpci_dev *zdev)
1041 {
1042 	zdev->pdev = pci_scan_single_device(zdev->bus, ZPCI_DEVFN);
1043 	if (!zdev->pdev) {
1044 		pr_err("pci_scan_single_device failed for fid: 0x%x\n",
1045 			zdev->fid);
1046 		goto out;
1047 	}
1048 
1049 	zpci_debug_init_device(zdev);
1050 	zpci_fmb_enable_device(zdev);
1051 	zpci_map_resources(zdev);
1052 	pci_bus_add_devices(zdev->bus);
1053 
1054 	/* now that pdev was added to the bus mark it as used */
1055 	zdev->state = ZPCI_FN_STATE_ONLINE;
1056 	return 0;
1057 
1058 out:
1059 	zpci_dma_exit_device(zdev);
1060 	clp_disable_fh(zdev);
1061 	return -EIO;
1062 }
1063 EXPORT_SYMBOL_GPL(zpci_scan_device);
1064 
1065 static inline int barsize(u8 size)
1066 {
1067 	return (size) ? (1 << size) >> 10 : 0;
1068 }
1069 
1070 static int zpci_mem_init(void)
1071 {
1072 	zdev_irq_cache = kmem_cache_create("PCI_IRQ_cache", sizeof(struct zdev_irq_map),
1073 				L1_CACHE_BYTES, SLAB_HWCACHE_ALIGN, NULL);
1074 	if (!zdev_irq_cache)
1075 		goto error_zdev;
1076 
1077 	zdev_fmb_cache = kmem_cache_create("PCI_FMB_cache", sizeof(struct zpci_fmb),
1078 				16, 0, NULL);
1079 	if (!zdev_fmb_cache)
1080 		goto error_fmb;
1081 
1082 	/* TODO: use realloc */
1083 	zpci_iomap_start = kzalloc(ZPCI_IOMAP_MAX_ENTRIES * sizeof(*zpci_iomap_start),
1084 				   GFP_KERNEL);
1085 	if (!zpci_iomap_start)
1086 		goto error_iomap;
1087 	return 0;
1088 
1089 error_iomap:
1090 	kmem_cache_destroy(zdev_fmb_cache);
1091 error_fmb:
1092 	kmem_cache_destroy(zdev_irq_cache);
1093 error_zdev:
1094 	return -ENOMEM;
1095 }
1096 
1097 static void zpci_mem_exit(void)
1098 {
1099 	kfree(zpci_iomap_start);
1100 	kmem_cache_destroy(zdev_irq_cache);
1101 	kmem_cache_destroy(zdev_fmb_cache);
1102 }
1103 
1104 unsigned int pci_probe = 1;
1105 EXPORT_SYMBOL_GPL(pci_probe);
1106 
1107 char * __init pcibios_setup(char *str)
1108 {
1109 	if (!strcmp(str, "off")) {
1110 		pci_probe = 0;
1111 		return NULL;
1112 	}
1113 	return str;
1114 }
1115 
1116 static int __init pci_base_init(void)
1117 {
1118 	int rc;
1119 
1120 	if (!pci_probe)
1121 		return 0;
1122 
1123 	if (!test_facility(2) || !test_facility(69)
1124 	    || !test_facility(71) || !test_facility(72))
1125 		return 0;
1126 
1127 	pr_info("Probing PCI hardware: PCI:%d  SID:%d  AEN:%d\n",
1128 		test_facility(69), test_facility(70),
1129 		test_facility(71));
1130 
1131 	rc = zpci_debug_init();
1132 	if (rc)
1133 		return rc;
1134 
1135 	rc = zpci_mem_init();
1136 	if (rc)
1137 		goto out_mem;
1138 
1139 	rc = zpci_msihash_init();
1140 	if (rc)
1141 		goto out_hash;
1142 
1143 	rc = zpci_irq_init();
1144 	if (rc)
1145 		goto out_irq;
1146 
1147 	rc = zpci_dma_init();
1148 	if (rc)
1149 		goto out_dma;
1150 
1151 	rc = clp_find_pci_devices();
1152 	if (rc)
1153 		goto out_find;
1154 
1155 	zpci_scan_devices();
1156 	return 0;
1157 
1158 out_find:
1159 	zpci_dma_exit();
1160 out_dma:
1161 	zpci_irq_exit();
1162 out_irq:
1163 	zpci_msihash_exit();
1164 out_hash:
1165 	zpci_mem_exit();
1166 out_mem:
1167 	zpci_debug_exit();
1168 	return rc;
1169 }
1170 subsys_initcall(pci_base_init);
1171