xref: /linux/arch/s390/pci/pci.c (revision 987b741c52c7c6c68d46fbaeb95b8d1087f10b7f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright IBM Corp. 2012
4  *
5  * Author(s):
6  *   Jan Glauber <jang@linux.vnet.ibm.com>
7  *
8  * The System z PCI code is a rewrite from a prototype by
9  * the following people (Kudoz!):
10  *   Alexander Schmidt
11  *   Christoph Raisch
12  *   Hannes Hering
13  *   Hoang-Nam Nguyen
14  *   Jan-Bernd Themann
15  *   Stefan Roscher
16  *   Thomas Klein
17  */
18 
19 #define KMSG_COMPONENT "zpci"
20 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
21 
22 #include <linux/kernel.h>
23 #include <linux/slab.h>
24 #include <linux/err.h>
25 #include <linux/export.h>
26 #include <linux/delay.h>
27 #include <linux/seq_file.h>
28 #include <linux/jump_label.h>
29 #include <linux/pci.h>
30 #include <linux/printk.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 #include "pci_bus.h"
40 #include "pci_iov.h"
41 
42 /* list of all detected zpci devices */
43 static LIST_HEAD(zpci_list);
44 static DEFINE_SPINLOCK(zpci_list_lock);
45 
46 static DECLARE_BITMAP(zpci_domain, ZPCI_DOMAIN_BITMAP_SIZE);
47 static DEFINE_SPINLOCK(zpci_domain_lock);
48 
49 #define ZPCI_IOMAP_ENTRIES						\
50 	min(((unsigned long) ZPCI_NR_DEVICES * PCI_STD_NUM_BARS / 2),	\
51 	    ZPCI_IOMAP_MAX_ENTRIES)
52 
53 unsigned int s390_pci_no_rid;
54 
55 static DEFINE_SPINLOCK(zpci_iomap_lock);
56 static unsigned long *zpci_iomap_bitmap;
57 struct zpci_iomap_entry *zpci_iomap_start;
58 EXPORT_SYMBOL_GPL(zpci_iomap_start);
59 
60 DEFINE_STATIC_KEY_FALSE(have_mio);
61 
62 static struct kmem_cache *zdev_fmb_cache;
63 
64 struct zpci_dev *get_zdev_by_fid(u32 fid)
65 {
66 	struct zpci_dev *tmp, *zdev = NULL;
67 
68 	spin_lock(&zpci_list_lock);
69 	list_for_each_entry(tmp, &zpci_list, entry) {
70 		if (tmp->fid == fid) {
71 			zdev = tmp;
72 			break;
73 		}
74 	}
75 	spin_unlock(&zpci_list_lock);
76 	return zdev;
77 }
78 
79 void zpci_remove_reserved_devices(void)
80 {
81 	struct zpci_dev *tmp, *zdev;
82 	enum zpci_state state;
83 	LIST_HEAD(remove);
84 
85 	spin_lock(&zpci_list_lock);
86 	list_for_each_entry_safe(zdev, tmp, &zpci_list, entry) {
87 		if (zdev->state == ZPCI_FN_STATE_STANDBY &&
88 		    !clp_get_state(zdev->fid, &state) &&
89 		    state == ZPCI_FN_STATE_RESERVED)
90 			list_move_tail(&zdev->entry, &remove);
91 	}
92 	spin_unlock(&zpci_list_lock);
93 
94 	list_for_each_entry_safe(zdev, tmp, &remove, entry)
95 		zpci_zdev_put(zdev);
96 }
97 
98 int pci_domain_nr(struct pci_bus *bus)
99 {
100 	return ((struct zpci_bus *) bus->sysdata)->domain_nr;
101 }
102 EXPORT_SYMBOL_GPL(pci_domain_nr);
103 
104 int pci_proc_domain(struct pci_bus *bus)
105 {
106 	return pci_domain_nr(bus);
107 }
108 EXPORT_SYMBOL_GPL(pci_proc_domain);
109 
110 /* Modify PCI: Register I/O address translation parameters */
111 int zpci_register_ioat(struct zpci_dev *zdev, u8 dmaas,
112 		       u64 base, u64 limit, u64 iota)
113 {
114 	u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, ZPCI_MOD_FC_REG_IOAT);
115 	struct zpci_fib fib = {0};
116 	u8 status;
117 
118 	WARN_ON_ONCE(iota & 0x3fff);
119 	fib.pba = base;
120 	fib.pal = limit;
121 	fib.iota = iota | ZPCI_IOTA_RTTO_FLAG;
122 	return zpci_mod_fc(req, &fib, &status) ? -EIO : 0;
123 }
124 
125 /* Modify PCI: Unregister I/O address translation parameters */
126 int zpci_unregister_ioat(struct zpci_dev *zdev, u8 dmaas)
127 {
128 	u64 req = ZPCI_CREATE_REQ(zdev->fh, dmaas, ZPCI_MOD_FC_DEREG_IOAT);
129 	struct zpci_fib fib = {0};
130 	u8 cc, status;
131 
132 	cc = zpci_mod_fc(req, &fib, &status);
133 	if (cc == 3) /* Function already gone. */
134 		cc = 0;
135 	return cc ? -EIO : 0;
136 }
137 
138 /* Modify PCI: Set PCI function measurement parameters */
139 int zpci_fmb_enable_device(struct zpci_dev *zdev)
140 {
141 	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
142 	struct zpci_fib fib = {0};
143 	u8 cc, status;
144 
145 	if (zdev->fmb || sizeof(*zdev->fmb) < zdev->fmb_length)
146 		return -EINVAL;
147 
148 	zdev->fmb = kmem_cache_zalloc(zdev_fmb_cache, GFP_KERNEL);
149 	if (!zdev->fmb)
150 		return -ENOMEM;
151 	WARN_ON((u64) zdev->fmb & 0xf);
152 
153 	/* reset software counters */
154 	atomic64_set(&zdev->allocated_pages, 0);
155 	atomic64_set(&zdev->mapped_pages, 0);
156 	atomic64_set(&zdev->unmapped_pages, 0);
157 
158 	fib.fmb_addr = virt_to_phys(zdev->fmb);
159 	cc = zpci_mod_fc(req, &fib, &status);
160 	if (cc) {
161 		kmem_cache_free(zdev_fmb_cache, zdev->fmb);
162 		zdev->fmb = NULL;
163 	}
164 	return cc ? -EIO : 0;
165 }
166 
167 /* Modify PCI: Disable PCI function measurement */
168 int zpci_fmb_disable_device(struct zpci_dev *zdev)
169 {
170 	u64 req = ZPCI_CREATE_REQ(zdev->fh, 0, ZPCI_MOD_FC_SET_MEASURE);
171 	struct zpci_fib fib = {0};
172 	u8 cc, status;
173 
174 	if (!zdev->fmb)
175 		return -EINVAL;
176 
177 	/* Function measurement is disabled if fmb address is zero */
178 	cc = zpci_mod_fc(req, &fib, &status);
179 	if (cc == 3) /* Function already gone. */
180 		cc = 0;
181 
182 	if (!cc) {
183 		kmem_cache_free(zdev_fmb_cache, zdev->fmb);
184 		zdev->fmb = NULL;
185 	}
186 	return cc ? -EIO : 0;
187 }
188 
189 static int zpci_cfg_load(struct zpci_dev *zdev, int offset, u32 *val, u8 len)
190 {
191 	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
192 	u64 data;
193 	int rc;
194 
195 	rc = __zpci_load(&data, req, offset);
196 	if (!rc) {
197 		data = le64_to_cpu((__force __le64) data);
198 		data >>= (8 - len) * 8;
199 		*val = (u32) data;
200 	} else
201 		*val = 0xffffffff;
202 	return rc;
203 }
204 
205 static int zpci_cfg_store(struct zpci_dev *zdev, int offset, u32 val, u8 len)
206 {
207 	u64 req = ZPCI_CREATE_REQ(zdev->fh, ZPCI_PCIAS_CFGSPC, len);
208 	u64 data = val;
209 	int rc;
210 
211 	data <<= (8 - len) * 8;
212 	data = (__force u64) cpu_to_le64(data);
213 	rc = __zpci_store(data, req, offset);
214 	return rc;
215 }
216 
217 resource_size_t pcibios_align_resource(void *data, const struct resource *res,
218 				       resource_size_t size,
219 				       resource_size_t align)
220 {
221 	return 0;
222 }
223 
224 /* combine single writes by using store-block insn */
225 void __iowrite64_copy(void __iomem *to, const void *from, size_t count)
226 {
227        zpci_memcpy_toio(to, from, count);
228 }
229 
230 static void __iomem *__ioremap(phys_addr_t addr, size_t size, pgprot_t prot)
231 {
232 	unsigned long offset, vaddr;
233 	struct vm_struct *area;
234 	phys_addr_t last_addr;
235 
236 	last_addr = addr + size - 1;
237 	if (!size || last_addr < addr)
238 		return NULL;
239 
240 	if (!static_branch_unlikely(&have_mio))
241 		return (void __iomem *) addr;
242 
243 	offset = addr & ~PAGE_MASK;
244 	addr &= PAGE_MASK;
245 	size = PAGE_ALIGN(size + offset);
246 	area = get_vm_area(size, VM_IOREMAP);
247 	if (!area)
248 		return NULL;
249 
250 	vaddr = (unsigned long) area->addr;
251 	if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
252 		free_vm_area(area);
253 		return NULL;
254 	}
255 	return (void __iomem *) ((unsigned long) area->addr + offset);
256 }
257 
258 void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
259 {
260 	return __ioremap(addr, size, __pgprot(prot));
261 }
262 EXPORT_SYMBOL(ioremap_prot);
263 
264 void __iomem *ioremap(phys_addr_t addr, size_t size)
265 {
266 	return __ioremap(addr, size, PAGE_KERNEL);
267 }
268 EXPORT_SYMBOL(ioremap);
269 
270 void __iomem *ioremap_wc(phys_addr_t addr, size_t size)
271 {
272 	return __ioremap(addr, size, pgprot_writecombine(PAGE_KERNEL));
273 }
274 EXPORT_SYMBOL(ioremap_wc);
275 
276 void __iomem *ioremap_wt(phys_addr_t addr, size_t size)
277 {
278 	return __ioremap(addr, size, pgprot_writethrough(PAGE_KERNEL));
279 }
280 EXPORT_SYMBOL(ioremap_wt);
281 
282 void iounmap(volatile void __iomem *addr)
283 {
284 	if (static_branch_likely(&have_mio))
285 		vunmap((__force void *) ((unsigned long) addr & PAGE_MASK));
286 }
287 EXPORT_SYMBOL(iounmap);
288 
289 /* Create a virtual mapping cookie for a PCI BAR */
290 static void __iomem *pci_iomap_range_fh(struct pci_dev *pdev, int bar,
291 					unsigned long offset, unsigned long max)
292 {
293 	struct zpci_dev *zdev =	to_zpci(pdev);
294 	int idx;
295 
296 	idx = zdev->bars[bar].map_idx;
297 	spin_lock(&zpci_iomap_lock);
298 	/* Detect overrun */
299 	WARN_ON(!++zpci_iomap_start[idx].count);
300 	zpci_iomap_start[idx].fh = zdev->fh;
301 	zpci_iomap_start[idx].bar = bar;
302 	spin_unlock(&zpci_iomap_lock);
303 
304 	return (void __iomem *) ZPCI_ADDR(idx) + offset;
305 }
306 
307 static void __iomem *pci_iomap_range_mio(struct pci_dev *pdev, int bar,
308 					 unsigned long offset,
309 					 unsigned long max)
310 {
311 	unsigned long barsize = pci_resource_len(pdev, bar);
312 	struct zpci_dev *zdev = to_zpci(pdev);
313 	void __iomem *iova;
314 
315 	iova = ioremap((unsigned long) zdev->bars[bar].mio_wt, barsize);
316 	return iova ? iova + offset : iova;
317 }
318 
319 void __iomem *pci_iomap_range(struct pci_dev *pdev, int bar,
320 			      unsigned long offset, unsigned long max)
321 {
322 	if (bar >= PCI_STD_NUM_BARS || !pci_resource_len(pdev, bar))
323 		return NULL;
324 
325 	if (static_branch_likely(&have_mio))
326 		return pci_iomap_range_mio(pdev, bar, offset, max);
327 	else
328 		return pci_iomap_range_fh(pdev, bar, offset, max);
329 }
330 EXPORT_SYMBOL(pci_iomap_range);
331 
332 void __iomem *pci_iomap(struct pci_dev *dev, int bar, unsigned long maxlen)
333 {
334 	return pci_iomap_range(dev, bar, 0, maxlen);
335 }
336 EXPORT_SYMBOL(pci_iomap);
337 
338 static void __iomem *pci_iomap_wc_range_mio(struct pci_dev *pdev, int bar,
339 					    unsigned long offset, unsigned long max)
340 {
341 	unsigned long barsize = pci_resource_len(pdev, bar);
342 	struct zpci_dev *zdev = to_zpci(pdev);
343 	void __iomem *iova;
344 
345 	iova = ioremap((unsigned long) zdev->bars[bar].mio_wb, barsize);
346 	return iova ? iova + offset : iova;
347 }
348 
349 void __iomem *pci_iomap_wc_range(struct pci_dev *pdev, int bar,
350 				 unsigned long offset, unsigned long max)
351 {
352 	if (bar >= PCI_STD_NUM_BARS || !pci_resource_len(pdev, bar))
353 		return NULL;
354 
355 	if (static_branch_likely(&have_mio))
356 		return pci_iomap_wc_range_mio(pdev, bar, offset, max);
357 	else
358 		return pci_iomap_range_fh(pdev, bar, offset, max);
359 }
360 EXPORT_SYMBOL(pci_iomap_wc_range);
361 
362 void __iomem *pci_iomap_wc(struct pci_dev *dev, int bar, unsigned long maxlen)
363 {
364 	return pci_iomap_wc_range(dev, bar, 0, maxlen);
365 }
366 EXPORT_SYMBOL(pci_iomap_wc);
367 
368 static void pci_iounmap_fh(struct pci_dev *pdev, void __iomem *addr)
369 {
370 	unsigned int idx = ZPCI_IDX(addr);
371 
372 	spin_lock(&zpci_iomap_lock);
373 	/* Detect underrun */
374 	WARN_ON(!zpci_iomap_start[idx].count);
375 	if (!--zpci_iomap_start[idx].count) {
376 		zpci_iomap_start[idx].fh = 0;
377 		zpci_iomap_start[idx].bar = 0;
378 	}
379 	spin_unlock(&zpci_iomap_lock);
380 }
381 
382 static void pci_iounmap_mio(struct pci_dev *pdev, void __iomem *addr)
383 {
384 	iounmap(addr);
385 }
386 
387 void pci_iounmap(struct pci_dev *pdev, void __iomem *addr)
388 {
389 	if (static_branch_likely(&have_mio))
390 		pci_iounmap_mio(pdev, addr);
391 	else
392 		pci_iounmap_fh(pdev, addr);
393 }
394 EXPORT_SYMBOL(pci_iounmap);
395 
396 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
397 		    int size, u32 *val)
398 {
399 	struct zpci_dev *zdev = get_zdev_by_bus(bus, devfn);
400 
401 	return (zdev) ? zpci_cfg_load(zdev, where, val, size) : -ENODEV;
402 }
403 
404 static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
405 		     int size, u32 val)
406 {
407 	struct zpci_dev *zdev = get_zdev_by_bus(bus, devfn);
408 
409 	return (zdev) ? zpci_cfg_store(zdev, where, val, size) : -ENODEV;
410 }
411 
412 static struct pci_ops pci_root_ops = {
413 	.read = pci_read,
414 	.write = pci_write,
415 };
416 
417 static void zpci_map_resources(struct pci_dev *pdev)
418 {
419 	struct zpci_dev *zdev = to_zpci(pdev);
420 	resource_size_t len;
421 	int i;
422 
423 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
424 		len = pci_resource_len(pdev, i);
425 		if (!len)
426 			continue;
427 
428 		if (zpci_use_mio(zdev))
429 			pdev->resource[i].start =
430 				(resource_size_t __force) zdev->bars[i].mio_wt;
431 		else
432 			pdev->resource[i].start = (resource_size_t __force)
433 				pci_iomap_range_fh(pdev, i, 0, 0);
434 		pdev->resource[i].end = pdev->resource[i].start + len - 1;
435 	}
436 
437 	zpci_iov_map_resources(pdev);
438 }
439 
440 static void zpci_unmap_resources(struct pci_dev *pdev)
441 {
442 	struct zpci_dev *zdev = to_zpci(pdev);
443 	resource_size_t len;
444 	int i;
445 
446 	if (zpci_use_mio(zdev))
447 		return;
448 
449 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
450 		len = pci_resource_len(pdev, i);
451 		if (!len)
452 			continue;
453 		pci_iounmap_fh(pdev, (void __iomem __force *)
454 			       pdev->resource[i].start);
455 	}
456 }
457 
458 static int zpci_alloc_iomap(struct zpci_dev *zdev)
459 {
460 	unsigned long entry;
461 
462 	spin_lock(&zpci_iomap_lock);
463 	entry = find_first_zero_bit(zpci_iomap_bitmap, ZPCI_IOMAP_ENTRIES);
464 	if (entry == ZPCI_IOMAP_ENTRIES) {
465 		spin_unlock(&zpci_iomap_lock);
466 		return -ENOSPC;
467 	}
468 	set_bit(entry, zpci_iomap_bitmap);
469 	spin_unlock(&zpci_iomap_lock);
470 	return entry;
471 }
472 
473 static void zpci_free_iomap(struct zpci_dev *zdev, int entry)
474 {
475 	spin_lock(&zpci_iomap_lock);
476 	memset(&zpci_iomap_start[entry], 0, sizeof(struct zpci_iomap_entry));
477 	clear_bit(entry, zpci_iomap_bitmap);
478 	spin_unlock(&zpci_iomap_lock);
479 }
480 
481 static struct resource *__alloc_res(struct zpci_dev *zdev, unsigned long start,
482 				    unsigned long size, unsigned long flags)
483 {
484 	struct resource *r;
485 
486 	r = kzalloc(sizeof(*r), GFP_KERNEL);
487 	if (!r)
488 		return NULL;
489 
490 	r->start = start;
491 	r->end = r->start + size - 1;
492 	r->flags = flags;
493 	r->name = zdev->res_name;
494 
495 	if (request_resource(&iomem_resource, r)) {
496 		kfree(r);
497 		return NULL;
498 	}
499 	return r;
500 }
501 
502 int zpci_setup_bus_resources(struct zpci_dev *zdev,
503 			     struct list_head *resources)
504 {
505 	unsigned long addr, size, flags;
506 	struct resource *res;
507 	int i, entry;
508 
509 	snprintf(zdev->res_name, sizeof(zdev->res_name),
510 		 "PCI Bus %04x:%02x", zdev->uid, ZPCI_BUS_NR);
511 
512 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
513 		if (!zdev->bars[i].size)
514 			continue;
515 		entry = zpci_alloc_iomap(zdev);
516 		if (entry < 0)
517 			return entry;
518 		zdev->bars[i].map_idx = entry;
519 
520 		/* only MMIO is supported */
521 		flags = IORESOURCE_MEM;
522 		if (zdev->bars[i].val & 8)
523 			flags |= IORESOURCE_PREFETCH;
524 		if (zdev->bars[i].val & 4)
525 			flags |= IORESOURCE_MEM_64;
526 
527 		if (zpci_use_mio(zdev))
528 			addr = (unsigned long) zdev->bars[i].mio_wt;
529 		else
530 			addr = ZPCI_ADDR(entry);
531 		size = 1UL << zdev->bars[i].size;
532 
533 		res = __alloc_res(zdev, addr, size, flags);
534 		if (!res) {
535 			zpci_free_iomap(zdev, entry);
536 			return -ENOMEM;
537 		}
538 		zdev->bars[i].res = res;
539 		pci_add_resource(resources, res);
540 	}
541 	zdev->has_resources = 1;
542 
543 	return 0;
544 }
545 
546 static void zpci_cleanup_bus_resources(struct zpci_dev *zdev)
547 {
548 	int i;
549 
550 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
551 		if (!zdev->bars[i].size || !zdev->bars[i].res)
552 			continue;
553 
554 		zpci_free_iomap(zdev, zdev->bars[i].map_idx);
555 		release_resource(zdev->bars[i].res);
556 		kfree(zdev->bars[i].res);
557 	}
558 	zdev->has_resources = 0;
559 }
560 
561 int pcibios_add_device(struct pci_dev *pdev)
562 {
563 	struct resource *res;
564 	int i;
565 
566 	if (pdev->is_physfn)
567 		pdev->no_vf_scan = 1;
568 
569 	pdev->dev.groups = zpci_attr_groups;
570 	pdev->dev.dma_ops = &s390_pci_dma_ops;
571 	zpci_map_resources(pdev);
572 
573 	for (i = 0; i < PCI_STD_NUM_BARS; i++) {
574 		res = &pdev->resource[i];
575 		if (res->parent || !res->flags)
576 			continue;
577 		pci_claim_resource(pdev, i);
578 	}
579 
580 	return 0;
581 }
582 
583 void pcibios_release_device(struct pci_dev *pdev)
584 {
585 	zpci_unmap_resources(pdev);
586 }
587 
588 int pcibios_enable_device(struct pci_dev *pdev, int mask)
589 {
590 	struct zpci_dev *zdev = to_zpci(pdev);
591 
592 	zpci_debug_init_device(zdev, dev_name(&pdev->dev));
593 	zpci_fmb_enable_device(zdev);
594 
595 	return pci_enable_resources(pdev, mask);
596 }
597 
598 void pcibios_disable_device(struct pci_dev *pdev)
599 {
600 	struct zpci_dev *zdev = to_zpci(pdev);
601 
602 	zpci_fmb_disable_device(zdev);
603 	zpci_debug_exit_device(zdev);
604 }
605 
606 static int __zpci_register_domain(int domain)
607 {
608 	spin_lock(&zpci_domain_lock);
609 	if (test_bit(domain, zpci_domain)) {
610 		spin_unlock(&zpci_domain_lock);
611 		pr_err("Domain %04x is already assigned\n", domain);
612 		return -EEXIST;
613 	}
614 	set_bit(domain, zpci_domain);
615 	spin_unlock(&zpci_domain_lock);
616 	return domain;
617 }
618 
619 static int __zpci_alloc_domain(void)
620 {
621 	int domain;
622 
623 	spin_lock(&zpci_domain_lock);
624 	/*
625 	 * We can always auto allocate domains below ZPCI_NR_DEVICES.
626 	 * There is either a free domain or we have reached the maximum in
627 	 * which case we would have bailed earlier.
628 	 */
629 	domain = find_first_zero_bit(zpci_domain, ZPCI_NR_DEVICES);
630 	set_bit(domain, zpci_domain);
631 	spin_unlock(&zpci_domain_lock);
632 	return domain;
633 }
634 
635 int zpci_alloc_domain(int domain)
636 {
637 	if (zpci_unique_uid) {
638 		if (domain)
639 			return __zpci_register_domain(domain);
640 		pr_warn("UID checking was active but no UID is provided: switching to automatic domain allocation\n");
641 		update_uid_checking(false);
642 	}
643 	return __zpci_alloc_domain();
644 }
645 
646 void zpci_free_domain(int domain)
647 {
648 	spin_lock(&zpci_domain_lock);
649 	clear_bit(domain, zpci_domain);
650 	spin_unlock(&zpci_domain_lock);
651 }
652 
653 
654 int zpci_enable_device(struct zpci_dev *zdev)
655 {
656 	int rc;
657 
658 	rc = clp_enable_fh(zdev, ZPCI_NR_DMA_SPACES);
659 	if (rc)
660 		goto out;
661 
662 	rc = zpci_dma_init_device(zdev);
663 	if (rc)
664 		goto out_dma;
665 
666 	return 0;
667 
668 out_dma:
669 	clp_disable_fh(zdev);
670 out:
671 	return rc;
672 }
673 
674 int zpci_disable_device(struct zpci_dev *zdev)
675 {
676 	zpci_dma_exit_device(zdev);
677 	/*
678 	 * The zPCI function may already be disabled by the platform, this is
679 	 * detected in clp_disable_fh() which becomes a no-op.
680 	 */
681 	return clp_disable_fh(zdev);
682 }
683 
684 /**
685  * zpci_create_device() - Create a new zpci_dev and add it to the zbus
686  * @fid: Function ID of the device to be created
687  * @fh: Current Function Handle of the device to be created
688  * @state: Initial state after creation either Standby or Configured
689  *
690  * Creates a new zpci device and adds it to its, possibly newly created, zbus
691  * as well as zpci_list.
692  *
693  * Returns: the zdev on success or an error pointer otherwise
694  */
695 struct zpci_dev *zpci_create_device(u32 fid, u32 fh, enum zpci_state state)
696 {
697 	struct zpci_dev *zdev;
698 	int rc;
699 
700 	zpci_dbg(3, "add fid:%x, fh:%x, c:%d\n", fid, fh, state);
701 	zdev = kzalloc(sizeof(*zdev), GFP_KERNEL);
702 	if (!zdev)
703 		return ERR_PTR(-ENOMEM);
704 
705 	/* FID and Function Handle are the static/dynamic identifiers */
706 	zdev->fid = fid;
707 	zdev->fh = fh;
708 
709 	/* Query function properties and update zdev */
710 	rc = clp_query_pci_fn(zdev);
711 	if (rc)
712 		goto error;
713 	zdev->state =  state;
714 
715 	kref_init(&zdev->kref);
716 	mutex_init(&zdev->lock);
717 
718 	rc = zpci_init_iommu(zdev);
719 	if (rc)
720 		goto error;
721 
722 	rc = zpci_bus_device_register(zdev, &pci_root_ops);
723 	if (rc)
724 		goto error_destroy_iommu;
725 
726 	spin_lock(&zpci_list_lock);
727 	list_add_tail(&zdev->entry, &zpci_list);
728 	spin_unlock(&zpci_list_lock);
729 
730 	return zdev;
731 
732 error_destroy_iommu:
733 	zpci_destroy_iommu(zdev);
734 error:
735 	zpci_dbg(0, "add fid:%x, rc:%d\n", fid, rc);
736 	kfree(zdev);
737 	return ERR_PTR(rc);
738 }
739 
740 /**
741  * zpci_scan_configured_device() - Scan a freshly configured zpci_dev
742  * @zdev: The zpci_dev to be configured
743  * @fh: The general function handle supplied by the platform
744  *
745  * Given a device in the configuration state Configured, enables, scans and
746  * adds it to the common code PCI subsystem if possible. If the PCI device is
747  * parked because we can not yet create a PCI bus because we have not seen
748  * function 0, it is ignored but will be scanned once function 0 appears.
749  * If any failure occurs, the zpci_dev is left disabled.
750  *
751  * Return: 0 on success, or an error code otherwise
752  */
753 int zpci_scan_configured_device(struct zpci_dev *zdev, u32 fh)
754 {
755 	int rc;
756 
757 	zdev->fh = fh;
758 	/* the PCI function will be scanned once function 0 appears */
759 	if (!zdev->zbus->bus)
760 		return 0;
761 
762 	/* For function 0 on a multi-function bus scan whole bus as we might
763 	 * have to pick up existing functions waiting for it to allow creating
764 	 * the PCI bus
765 	 */
766 	if (zdev->devfn == 0 && zdev->zbus->multifunction)
767 		rc = zpci_bus_scan_bus(zdev->zbus);
768 	else
769 		rc = zpci_bus_scan_device(zdev);
770 
771 	return rc;
772 }
773 
774 /**
775  * zpci_deconfigure_device() - Deconfigure a zpci_dev
776  * @zdev: The zpci_dev to configure
777  *
778  * Deconfigure a zPCI function that is currently configured and possibly known
779  * to the common code PCI subsystem.
780  * If any failure occurs the device is left as is.
781  *
782  * Return: 0 on success, or an error code otherwise
783  */
784 int zpci_deconfigure_device(struct zpci_dev *zdev)
785 {
786 	int rc;
787 
788 	if (zdev->zbus->bus)
789 		zpci_bus_remove_device(zdev, false);
790 
791 	if (zdev_enabled(zdev)) {
792 		rc = zpci_disable_device(zdev);
793 		if (rc)
794 			return rc;
795 	}
796 
797 	rc = sclp_pci_deconfigure(zdev->fid);
798 	zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, rc);
799 	if (rc)
800 		return rc;
801 	zdev->state = ZPCI_FN_STATE_STANDBY;
802 
803 	return 0;
804 }
805 
806 void zpci_release_device(struct kref *kref)
807 {
808 	struct zpci_dev *zdev = container_of(kref, struct zpci_dev, kref);
809 	int ret;
810 
811 	if (zdev->zbus->bus)
812 		zpci_bus_remove_device(zdev, false);
813 
814 	if (zdev_enabled(zdev))
815 		zpci_disable_device(zdev);
816 
817 	switch (zdev->state) {
818 	case ZPCI_FN_STATE_CONFIGURED:
819 		ret = sclp_pci_deconfigure(zdev->fid);
820 		zpci_dbg(3, "deconf fid:%x, rc:%d\n", zdev->fid, ret);
821 		fallthrough;
822 	case ZPCI_FN_STATE_STANDBY:
823 		if (zdev->has_hp_slot)
824 			zpci_exit_slot(zdev);
825 		zpci_cleanup_bus_resources(zdev);
826 		zpci_bus_device_unregister(zdev);
827 		zpci_destroy_iommu(zdev);
828 		fallthrough;
829 	default:
830 		break;
831 	}
832 
833 	spin_lock(&zpci_list_lock);
834 	list_del(&zdev->entry);
835 	spin_unlock(&zpci_list_lock);
836 	zpci_dbg(3, "rem fid:%x\n", zdev->fid);
837 	kfree(zdev);
838 }
839 
840 int zpci_report_error(struct pci_dev *pdev,
841 		      struct zpci_report_error_header *report)
842 {
843 	struct zpci_dev *zdev = to_zpci(pdev);
844 
845 	return sclp_pci_report(report, zdev->fh, zdev->fid);
846 }
847 EXPORT_SYMBOL(zpci_report_error);
848 
849 static int zpci_mem_init(void)
850 {
851 	BUILD_BUG_ON(!is_power_of_2(__alignof__(struct zpci_fmb)) ||
852 		     __alignof__(struct zpci_fmb) < sizeof(struct zpci_fmb));
853 
854 	zdev_fmb_cache = kmem_cache_create("PCI_FMB_cache", sizeof(struct zpci_fmb),
855 					   __alignof__(struct zpci_fmb), 0, NULL);
856 	if (!zdev_fmb_cache)
857 		goto error_fmb;
858 
859 	zpci_iomap_start = kcalloc(ZPCI_IOMAP_ENTRIES,
860 				   sizeof(*zpci_iomap_start), GFP_KERNEL);
861 	if (!zpci_iomap_start)
862 		goto error_iomap;
863 
864 	zpci_iomap_bitmap = kcalloc(BITS_TO_LONGS(ZPCI_IOMAP_ENTRIES),
865 				    sizeof(*zpci_iomap_bitmap), GFP_KERNEL);
866 	if (!zpci_iomap_bitmap)
867 		goto error_iomap_bitmap;
868 
869 	if (static_branch_likely(&have_mio))
870 		clp_setup_writeback_mio();
871 
872 	return 0;
873 error_iomap_bitmap:
874 	kfree(zpci_iomap_start);
875 error_iomap:
876 	kmem_cache_destroy(zdev_fmb_cache);
877 error_fmb:
878 	return -ENOMEM;
879 }
880 
881 static void zpci_mem_exit(void)
882 {
883 	kfree(zpci_iomap_bitmap);
884 	kfree(zpci_iomap_start);
885 	kmem_cache_destroy(zdev_fmb_cache);
886 }
887 
888 static unsigned int s390_pci_probe __initdata = 1;
889 static unsigned int s390_pci_no_mio __initdata;
890 unsigned int s390_pci_force_floating __initdata;
891 static unsigned int s390_pci_initialized;
892 
893 char * __init pcibios_setup(char *str)
894 {
895 	if (!strcmp(str, "off")) {
896 		s390_pci_probe = 0;
897 		return NULL;
898 	}
899 	if (!strcmp(str, "nomio")) {
900 		s390_pci_no_mio = 1;
901 		return NULL;
902 	}
903 	if (!strcmp(str, "force_floating")) {
904 		s390_pci_force_floating = 1;
905 		return NULL;
906 	}
907 	if (!strcmp(str, "norid")) {
908 		s390_pci_no_rid = 1;
909 		return NULL;
910 	}
911 	return str;
912 }
913 
914 bool zpci_is_enabled(void)
915 {
916 	return s390_pci_initialized;
917 }
918 
919 static int __init pci_base_init(void)
920 {
921 	int rc;
922 
923 	if (!s390_pci_probe)
924 		return 0;
925 
926 	if (!test_facility(69) || !test_facility(71)) {
927 		pr_info("PCI is not supported because CPU facilities 69 or 71 are not available\n");
928 		return 0;
929 	}
930 
931 	if (test_facility(153) && !s390_pci_no_mio) {
932 		static_branch_enable(&have_mio);
933 		ctl_set_bit(2, 5);
934 	}
935 
936 	rc = zpci_debug_init();
937 	if (rc)
938 		goto out;
939 
940 	rc = zpci_mem_init();
941 	if (rc)
942 		goto out_mem;
943 
944 	rc = zpci_irq_init();
945 	if (rc)
946 		goto out_irq;
947 
948 	rc = zpci_dma_init();
949 	if (rc)
950 		goto out_dma;
951 
952 	rc = clp_scan_pci_devices();
953 	if (rc)
954 		goto out_find;
955 	zpci_bus_scan_busses();
956 
957 	s390_pci_initialized = 1;
958 	return 0;
959 
960 out_find:
961 	zpci_dma_exit();
962 out_dma:
963 	zpci_irq_exit();
964 out_irq:
965 	zpci_mem_exit();
966 out_mem:
967 	zpci_debug_exit();
968 out:
969 	return rc;
970 }
971 subsys_initcall_sync(pci_base_init);
972