xref: /openbmc/linux/arch/ia64/pci/pci.c (revision 93d90ad7)
1 /*
2  * pci.c - Low-Level PCI Access in IA-64
3  *
4  * Derived from bios32.c of i386 tree.
5  *
6  * (c) Copyright 2002, 2005 Hewlett-Packard Development Company, L.P.
7  *	David Mosberger-Tang <davidm@hpl.hp.com>
8  *	Bjorn Helgaas <bjorn.helgaas@hp.com>
9  * Copyright (C) 2004 Silicon Graphics, Inc.
10  *
11  * Note: Above list of copyright holders is incomplete...
12  */
13 
14 #include <linux/acpi.h>
15 #include <linux/types.h>
16 #include <linux/kernel.h>
17 #include <linux/pci.h>
18 #include <linux/pci-acpi.h>
19 #include <linux/init.h>
20 #include <linux/ioport.h>
21 #include <linux/slab.h>
22 #include <linux/spinlock.h>
23 #include <linux/bootmem.h>
24 #include <linux/export.h>
25 
26 #include <asm/machvec.h>
27 #include <asm/page.h>
28 #include <asm/io.h>
29 #include <asm/sal.h>
30 #include <asm/smp.h>
31 #include <asm/irq.h>
32 #include <asm/hw_irq.h>
33 
34 /*
35  * Low-level SAL-based PCI configuration access functions. Note that SAL
36  * calls are already serialized (via sal_lock), so we don't need another
37  * synchronization mechanism here.
38  */
39 
40 #define PCI_SAL_ADDRESS(seg, bus, devfn, reg)		\
41 	(((u64) seg << 24) | (bus << 16) | (devfn << 8) | (reg))
42 
43 /* SAL 3.2 adds support for extended config space. */
44 
45 #define PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg)	\
46 	(((u64) seg << 28) | (bus << 20) | (devfn << 12) | (reg))
47 
48 int raw_pci_read(unsigned int seg, unsigned int bus, unsigned int devfn,
49 	      int reg, int len, u32 *value)
50 {
51 	u64 addr, data = 0;
52 	int mode, result;
53 
54 	if (!value || (seg > 65535) || (bus > 255) || (devfn > 255) || (reg > 4095))
55 		return -EINVAL;
56 
57 	if ((seg | reg) <= 255) {
58 		addr = PCI_SAL_ADDRESS(seg, bus, devfn, reg);
59 		mode = 0;
60 	} else if (sal_revision >= SAL_VERSION_CODE(3,2)) {
61 		addr = PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg);
62 		mode = 1;
63 	} else {
64 		return -EINVAL;
65 	}
66 
67 	result = ia64_sal_pci_config_read(addr, mode, len, &data);
68 	if (result != 0)
69 		return -EINVAL;
70 
71 	*value = (u32) data;
72 	return 0;
73 }
74 
75 int raw_pci_write(unsigned int seg, unsigned int bus, unsigned int devfn,
76 	       int reg, int len, u32 value)
77 {
78 	u64 addr;
79 	int mode, result;
80 
81 	if ((seg > 65535) || (bus > 255) || (devfn > 255) || (reg > 4095))
82 		return -EINVAL;
83 
84 	if ((seg | reg) <= 255) {
85 		addr = PCI_SAL_ADDRESS(seg, bus, devfn, reg);
86 		mode = 0;
87 	} else if (sal_revision >= SAL_VERSION_CODE(3,2)) {
88 		addr = PCI_SAL_EXT_ADDRESS(seg, bus, devfn, reg);
89 		mode = 1;
90 	} else {
91 		return -EINVAL;
92 	}
93 	result = ia64_sal_pci_config_write(addr, mode, len, value);
94 	if (result != 0)
95 		return -EINVAL;
96 	return 0;
97 }
98 
99 static int pci_read(struct pci_bus *bus, unsigned int devfn, int where,
100 							int size, u32 *value)
101 {
102 	return raw_pci_read(pci_domain_nr(bus), bus->number,
103 				 devfn, where, size, value);
104 }
105 
106 static int pci_write(struct pci_bus *bus, unsigned int devfn, int where,
107 							int size, u32 value)
108 {
109 	return raw_pci_write(pci_domain_nr(bus), bus->number,
110 				  devfn, where, size, value);
111 }
112 
113 struct pci_ops pci_root_ops = {
114 	.read = pci_read,
115 	.write = pci_write,
116 };
117 
118 /* Called by ACPI when it finds a new root bus.  */
119 
120 static struct pci_controller *alloc_pci_controller(int seg)
121 {
122 	struct pci_controller *controller;
123 
124 	controller = kzalloc(sizeof(*controller), GFP_KERNEL);
125 	if (!controller)
126 		return NULL;
127 
128 	controller->segment = seg;
129 	return controller;
130 }
131 
132 struct pci_root_info {
133 	struct acpi_device *bridge;
134 	struct pci_controller *controller;
135 	struct list_head resources;
136 	struct resource *res;
137 	resource_size_t *res_offset;
138 	unsigned int res_num;
139 	struct list_head io_resources;
140 	char *name;
141 };
142 
143 static unsigned int
144 new_space (u64 phys_base, int sparse)
145 {
146 	u64 mmio_base;
147 	int i;
148 
149 	if (phys_base == 0)
150 		return 0;	/* legacy I/O port space */
151 
152 	mmio_base = (u64) ioremap(phys_base, 0);
153 	for (i = 0; i < num_io_spaces; i++)
154 		if (io_space[i].mmio_base == mmio_base &&
155 		    io_space[i].sparse == sparse)
156 			return i;
157 
158 	if (num_io_spaces == MAX_IO_SPACES) {
159 		pr_err("PCI: Too many IO port spaces "
160 			"(MAX_IO_SPACES=%lu)\n", MAX_IO_SPACES);
161 		return ~0;
162 	}
163 
164 	i = num_io_spaces++;
165 	io_space[i].mmio_base = mmio_base;
166 	io_space[i].sparse = sparse;
167 
168 	return i;
169 }
170 
171 static u64 add_io_space(struct pci_root_info *info,
172 			struct acpi_resource_address64 *addr)
173 {
174 	struct iospace_resource *iospace;
175 	struct resource *resource;
176 	char *name;
177 	unsigned long base, min, max, base_port;
178 	unsigned int sparse = 0, space_nr, len;
179 
180 	len = strlen(info->name) + 32;
181 	iospace = kzalloc(sizeof(*iospace) + len, GFP_KERNEL);
182 	if (!iospace) {
183 		dev_err(&info->bridge->dev,
184 				"PCI: No memory for %s I/O port space\n",
185 				info->name);
186 		goto out;
187 	}
188 
189 	name = (char *)(iospace + 1);
190 
191 	min = addr->minimum;
192 	max = min + addr->address_length - 1;
193 	if (addr->info.io.translation_type == ACPI_SPARSE_TRANSLATION)
194 		sparse = 1;
195 
196 	space_nr = new_space(addr->translation_offset, sparse);
197 	if (space_nr == ~0)
198 		goto free_resource;
199 
200 	base = __pa(io_space[space_nr].mmio_base);
201 	base_port = IO_SPACE_BASE(space_nr);
202 	snprintf(name, len, "%s I/O Ports %08lx-%08lx", info->name,
203 		base_port + min, base_port + max);
204 
205 	/*
206 	 * The SDM guarantees the legacy 0-64K space is sparse, but if the
207 	 * mapping is done by the processor (not the bridge), ACPI may not
208 	 * mark it as sparse.
209 	 */
210 	if (space_nr == 0)
211 		sparse = 1;
212 
213 	resource = &iospace->res;
214 	resource->name  = name;
215 	resource->flags = IORESOURCE_MEM;
216 	resource->start = base + (sparse ? IO_SPACE_SPARSE_ENCODING(min) : min);
217 	resource->end   = base + (sparse ? IO_SPACE_SPARSE_ENCODING(max) : max);
218 	if (insert_resource(&iomem_resource, resource)) {
219 		dev_err(&info->bridge->dev,
220 				"can't allocate host bridge io space resource  %pR\n",
221 				resource);
222 		goto free_resource;
223 	}
224 
225 	list_add_tail(&iospace->list, &info->io_resources);
226 	return base_port;
227 
228 free_resource:
229 	kfree(iospace);
230 out:
231 	return ~0;
232 }
233 
234 static acpi_status resource_to_window(struct acpi_resource *resource,
235 				      struct acpi_resource_address64 *addr)
236 {
237 	acpi_status status;
238 
239 	/*
240 	 * We're only interested in _CRS descriptors that are
241 	 *	- address space descriptors for memory or I/O space
242 	 *	- non-zero size
243 	 *	- producers, i.e., the address space is routed downstream,
244 	 *	  not consumed by the bridge itself
245 	 */
246 	status = acpi_resource_to_address64(resource, addr);
247 	if (ACPI_SUCCESS(status) &&
248 	    (addr->resource_type == ACPI_MEMORY_RANGE ||
249 	     addr->resource_type == ACPI_IO_RANGE) &&
250 	    addr->address_length &&
251 	    addr->producer_consumer == ACPI_PRODUCER)
252 		return AE_OK;
253 
254 	return AE_ERROR;
255 }
256 
257 static acpi_status count_window(struct acpi_resource *resource, void *data)
258 {
259 	unsigned int *windows = (unsigned int *) data;
260 	struct acpi_resource_address64 addr;
261 	acpi_status status;
262 
263 	status = resource_to_window(resource, &addr);
264 	if (ACPI_SUCCESS(status))
265 		(*windows)++;
266 
267 	return AE_OK;
268 }
269 
270 static acpi_status add_window(struct acpi_resource *res, void *data)
271 {
272 	struct pci_root_info *info = data;
273 	struct resource *resource;
274 	struct acpi_resource_address64 addr;
275 	acpi_status status;
276 	unsigned long flags, offset = 0;
277 	struct resource *root;
278 
279 	/* Return AE_OK for non-window resources to keep scanning for more */
280 	status = resource_to_window(res, &addr);
281 	if (!ACPI_SUCCESS(status))
282 		return AE_OK;
283 
284 	if (addr.resource_type == ACPI_MEMORY_RANGE) {
285 		flags = IORESOURCE_MEM;
286 		root = &iomem_resource;
287 		offset = addr.translation_offset;
288 	} else if (addr.resource_type == ACPI_IO_RANGE) {
289 		flags = IORESOURCE_IO;
290 		root = &ioport_resource;
291 		offset = add_io_space(info, &addr);
292 		if (offset == ~0)
293 			return AE_OK;
294 	} else
295 		return AE_OK;
296 
297 	resource = &info->res[info->res_num];
298 	resource->name = info->name;
299 	resource->flags = flags;
300 	resource->start = addr.minimum + offset;
301 	resource->end = resource->start + addr.address_length - 1;
302 	info->res_offset[info->res_num] = offset;
303 
304 	if (insert_resource(root, resource)) {
305 		dev_err(&info->bridge->dev,
306 			"can't allocate host bridge window %pR\n",
307 			resource);
308 	} else {
309 		if (offset)
310 			dev_info(&info->bridge->dev, "host bridge window %pR "
311 				 "(PCI address [%#llx-%#llx])\n",
312 				 resource,
313 				 resource->start - offset,
314 				 resource->end - offset);
315 		else
316 			dev_info(&info->bridge->dev,
317 				 "host bridge window %pR\n", resource);
318 	}
319 	/* HP's firmware has a hack to work around a Windows bug.
320 	 * Ignore these tiny memory ranges */
321 	if (!((resource->flags & IORESOURCE_MEM) &&
322 	      (resource->end - resource->start < 16)))
323 		pci_add_resource_offset(&info->resources, resource,
324 					info->res_offset[info->res_num]);
325 
326 	info->res_num++;
327 	return AE_OK;
328 }
329 
330 static void free_pci_root_info_res(struct pci_root_info *info)
331 {
332 	struct iospace_resource *iospace, *tmp;
333 
334 	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list)
335 		kfree(iospace);
336 
337 	kfree(info->name);
338 	kfree(info->res);
339 	info->res = NULL;
340 	kfree(info->res_offset);
341 	info->res_offset = NULL;
342 	info->res_num = 0;
343 	kfree(info->controller);
344 	info->controller = NULL;
345 }
346 
347 static void __release_pci_root_info(struct pci_root_info *info)
348 {
349 	int i;
350 	struct resource *res;
351 	struct iospace_resource *iospace;
352 
353 	list_for_each_entry(iospace, &info->io_resources, list)
354 		release_resource(&iospace->res);
355 
356 	for (i = 0; i < info->res_num; i++) {
357 		res = &info->res[i];
358 
359 		if (!res->parent)
360 			continue;
361 
362 		if (!(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
363 			continue;
364 
365 		release_resource(res);
366 	}
367 
368 	free_pci_root_info_res(info);
369 	kfree(info);
370 }
371 
372 static void release_pci_root_info(struct pci_host_bridge *bridge)
373 {
374 	struct pci_root_info *info = bridge->release_data;
375 
376 	__release_pci_root_info(info);
377 }
378 
379 static int
380 probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
381 		int busnum, int domain)
382 {
383 	char *name;
384 
385 	name = kmalloc(16, GFP_KERNEL);
386 	if (!name)
387 		return -ENOMEM;
388 
389 	sprintf(name, "PCI Bus %04x:%02x", domain, busnum);
390 	info->bridge = device;
391 	info->name = name;
392 
393 	acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_window,
394 			&info->res_num);
395 	if (info->res_num) {
396 		info->res =
397 			kzalloc_node(sizeof(*info->res) * info->res_num,
398 				     GFP_KERNEL, info->controller->node);
399 		if (!info->res) {
400 			kfree(name);
401 			return -ENOMEM;
402 		}
403 
404 		info->res_offset =
405 			kzalloc_node(sizeof(*info->res_offset) * info->res_num,
406 					GFP_KERNEL, info->controller->node);
407 		if (!info->res_offset) {
408 			kfree(name);
409 			kfree(info->res);
410 			info->res = NULL;
411 			return -ENOMEM;
412 		}
413 
414 		info->res_num = 0;
415 		acpi_walk_resources(device->handle, METHOD_NAME__CRS,
416 			add_window, info);
417 	} else
418 		kfree(name);
419 
420 	return 0;
421 }
422 
423 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
424 {
425 	struct acpi_device *device = root->device;
426 	int domain = root->segment;
427 	int bus = root->secondary.start;
428 	struct pci_controller *controller;
429 	struct pci_root_info *info = NULL;
430 	int busnum = root->secondary.start;
431 	struct pci_bus *pbus;
432 	int ret;
433 
434 	controller = alloc_pci_controller(domain);
435 	if (!controller)
436 		return NULL;
437 
438 	controller->companion = device;
439 	controller->node = acpi_get_node(device->handle);
440 
441 	info = kzalloc(sizeof(*info), GFP_KERNEL);
442 	if (!info) {
443 		dev_err(&device->dev,
444 				"pci_bus %04x:%02x: ignored (out of memory)\n",
445 				domain, busnum);
446 		kfree(controller);
447 		return NULL;
448 	}
449 
450 	info->controller = controller;
451 	INIT_LIST_HEAD(&info->io_resources);
452 	INIT_LIST_HEAD(&info->resources);
453 
454 	ret = probe_pci_root_info(info, device, busnum, domain);
455 	if (ret) {
456 		kfree(info->controller);
457 		kfree(info);
458 		return NULL;
459 	}
460 	/* insert busn resource at first */
461 	pci_add_resource(&info->resources, &root->secondary);
462 	/*
463 	 * See arch/x86/pci/acpi.c.
464 	 * The desired pci bus might already be scanned in a quirk. We
465 	 * should handle the case here, but it appears that IA64 hasn't
466 	 * such quirk. So we just ignore the case now.
467 	 */
468 	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops, controller,
469 				   &info->resources);
470 	if (!pbus) {
471 		pci_free_resource_list(&info->resources);
472 		__release_pci_root_info(info);
473 		return NULL;
474 	}
475 
476 	pci_set_host_bridge_release(to_pci_host_bridge(pbus->bridge),
477 			release_pci_root_info, info);
478 	pci_scan_child_bus(pbus);
479 	return pbus;
480 }
481 
482 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
483 {
484 	struct pci_controller *controller = bridge->bus->sysdata;
485 
486 	ACPI_COMPANION_SET(&bridge->dev, controller->companion);
487 	return 0;
488 }
489 
490 static int is_valid_resource(struct pci_dev *dev, int idx)
491 {
492 	unsigned int i, type_mask = IORESOURCE_IO | IORESOURCE_MEM;
493 	struct resource *devr = &dev->resource[idx], *busr;
494 
495 	if (!dev->bus)
496 		return 0;
497 
498 	pci_bus_for_each_resource(dev->bus, busr, i) {
499 		if (!busr || ((busr->flags ^ devr->flags) & type_mask))
500 			continue;
501 		if ((devr->start) && (devr->start >= busr->start) &&
502 				(devr->end <= busr->end))
503 			return 1;
504 	}
505 	return 0;
506 }
507 
508 static void pcibios_fixup_resources(struct pci_dev *dev, int start, int limit)
509 {
510 	int i;
511 
512 	for (i = start; i < limit; i++) {
513 		if (!dev->resource[i].flags)
514 			continue;
515 		if ((is_valid_resource(dev, i)))
516 			pci_claim_resource(dev, i);
517 	}
518 }
519 
520 void pcibios_fixup_device_resources(struct pci_dev *dev)
521 {
522 	pcibios_fixup_resources(dev, 0, PCI_BRIDGE_RESOURCES);
523 }
524 EXPORT_SYMBOL_GPL(pcibios_fixup_device_resources);
525 
526 static void pcibios_fixup_bridge_resources(struct pci_dev *dev)
527 {
528 	pcibios_fixup_resources(dev, PCI_BRIDGE_RESOURCES, PCI_NUM_RESOURCES);
529 }
530 
531 /*
532  *  Called after each bus is probed, but before its children are examined.
533  */
534 void pcibios_fixup_bus(struct pci_bus *b)
535 {
536 	struct pci_dev *dev;
537 
538 	if (b->self) {
539 		pci_read_bridge_bases(b);
540 		pcibios_fixup_bridge_resources(b->self);
541 	}
542 	list_for_each_entry(dev, &b->devices, bus_list)
543 		pcibios_fixup_device_resources(dev);
544 	platform_pci_fixup_bus(b);
545 }
546 
547 void pcibios_add_bus(struct pci_bus *bus)
548 {
549 	acpi_pci_add_bus(bus);
550 }
551 
552 void pcibios_remove_bus(struct pci_bus *bus)
553 {
554 	acpi_pci_remove_bus(bus);
555 }
556 
557 void pcibios_set_master (struct pci_dev *dev)
558 {
559 	/* No special bus mastering setup handling */
560 }
561 
562 int
563 pcibios_enable_device (struct pci_dev *dev, int mask)
564 {
565 	int ret;
566 
567 	ret = pci_enable_resources(dev, mask);
568 	if (ret < 0)
569 		return ret;
570 
571 	if (!dev->msi_enabled)
572 		return acpi_pci_irq_enable(dev);
573 	return 0;
574 }
575 
576 void
577 pcibios_disable_device (struct pci_dev *dev)
578 {
579 	BUG_ON(atomic_read(&dev->enable_cnt));
580 	if (!dev->msi_enabled)
581 		acpi_pci_irq_disable(dev);
582 }
583 
584 resource_size_t
585 pcibios_align_resource (void *data, const struct resource *res,
586 		        resource_size_t size, resource_size_t align)
587 {
588 	return res->start;
589 }
590 
591 int
592 pci_mmap_page_range (struct pci_dev *dev, struct vm_area_struct *vma,
593 		     enum pci_mmap_state mmap_state, int write_combine)
594 {
595 	unsigned long size = vma->vm_end - vma->vm_start;
596 	pgprot_t prot;
597 
598 	/*
599 	 * I/O space cannot be accessed via normal processor loads and
600 	 * stores on this platform.
601 	 */
602 	if (mmap_state == pci_mmap_io)
603 		/*
604 		 * XXX we could relax this for I/O spaces for which ACPI
605 		 * indicates that the space is 1-to-1 mapped.  But at the
606 		 * moment, we don't support multiple PCI address spaces and
607 		 * the legacy I/O space is not 1-to-1 mapped, so this is moot.
608 		 */
609 		return -EINVAL;
610 
611 	if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size))
612 		return -EINVAL;
613 
614 	prot = phys_mem_access_prot(NULL, vma->vm_pgoff, size,
615 				    vma->vm_page_prot);
616 
617 	/*
618 	 * If the user requested WC, the kernel uses UC or WC for this region,
619 	 * and the chipset supports WC, we can use WC. Otherwise, we have to
620 	 * use the same attribute the kernel uses.
621 	 */
622 	if (write_combine &&
623 	    ((pgprot_val(prot) & _PAGE_MA_MASK) == _PAGE_MA_UC ||
624 	     (pgprot_val(prot) & _PAGE_MA_MASK) == _PAGE_MA_WC) &&
625 	    efi_range_is_wc(vma->vm_start, vma->vm_end - vma->vm_start))
626 		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
627 	else
628 		vma->vm_page_prot = prot;
629 
630 	if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
631 			     vma->vm_end - vma->vm_start, vma->vm_page_prot))
632 		return -EAGAIN;
633 
634 	return 0;
635 }
636 
637 /**
638  * ia64_pci_get_legacy_mem - generic legacy mem routine
639  * @bus: bus to get legacy memory base address for
640  *
641  * Find the base of legacy memory for @bus.  This is typically the first
642  * megabyte of bus address space for @bus or is simply 0 on platforms whose
643  * chipsets support legacy I/O and memory routing.  Returns the base address
644  * or an error pointer if an error occurred.
645  *
646  * This is the ia64 generic version of this routine.  Other platforms
647  * are free to override it with a machine vector.
648  */
649 char *ia64_pci_get_legacy_mem(struct pci_bus *bus)
650 {
651 	return (char *)__IA64_UNCACHED_OFFSET;
652 }
653 
654 /**
655  * pci_mmap_legacy_page_range - map legacy memory space to userland
656  * @bus: bus whose legacy space we're mapping
657  * @vma: vma passed in by mmap
658  *
659  * Map legacy memory space for this device back to userspace using a machine
660  * vector to get the base address.
661  */
662 int
663 pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma,
664 			   enum pci_mmap_state mmap_state)
665 {
666 	unsigned long size = vma->vm_end - vma->vm_start;
667 	pgprot_t prot;
668 	char *addr;
669 
670 	/* We only support mmap'ing of legacy memory space */
671 	if (mmap_state != pci_mmap_mem)
672 		return -ENOSYS;
673 
674 	/*
675 	 * Avoid attribute aliasing.  See Documentation/ia64/aliasing.txt
676 	 * for more details.
677 	 */
678 	if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size))
679 		return -EINVAL;
680 	prot = phys_mem_access_prot(NULL, vma->vm_pgoff, size,
681 				    vma->vm_page_prot);
682 
683 	addr = pci_get_legacy_mem(bus);
684 	if (IS_ERR(addr))
685 		return PTR_ERR(addr);
686 
687 	vma->vm_pgoff += (unsigned long)addr >> PAGE_SHIFT;
688 	vma->vm_page_prot = prot;
689 
690 	if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
691 			    size, vma->vm_page_prot))
692 		return -EAGAIN;
693 
694 	return 0;
695 }
696 
697 /**
698  * ia64_pci_legacy_read - read from legacy I/O space
699  * @bus: bus to read
700  * @port: legacy port value
701  * @val: caller allocated storage for returned value
702  * @size: number of bytes to read
703  *
704  * Simply reads @size bytes from @port and puts the result in @val.
705  *
706  * Again, this (and the write routine) are generic versions that can be
707  * overridden by the platform.  This is necessary on platforms that don't
708  * support legacy I/O routing or that hard fail on legacy I/O timeouts.
709  */
710 int ia64_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size)
711 {
712 	int ret = size;
713 
714 	switch (size) {
715 	case 1:
716 		*val = inb(port);
717 		break;
718 	case 2:
719 		*val = inw(port);
720 		break;
721 	case 4:
722 		*val = inl(port);
723 		break;
724 	default:
725 		ret = -EINVAL;
726 		break;
727 	}
728 
729 	return ret;
730 }
731 
732 /**
733  * ia64_pci_legacy_write - perform a legacy I/O write
734  * @bus: bus pointer
735  * @port: port to write
736  * @val: value to write
737  * @size: number of bytes to write from @val
738  *
739  * Simply writes @size bytes of @val to @port.
740  */
741 int ia64_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size)
742 {
743 	int ret = size;
744 
745 	switch (size) {
746 	case 1:
747 		outb(val, port);
748 		break;
749 	case 2:
750 		outw(val, port);
751 		break;
752 	case 4:
753 		outl(val, port);
754 		break;
755 	default:
756 		ret = -EINVAL;
757 		break;
758 	}
759 
760 	return ret;
761 }
762 
763 /**
764  * set_pci_cacheline_size - determine cacheline size for PCI devices
765  *
766  * We want to use the line-size of the outer-most cache.  We assume
767  * that this line-size is the same for all CPUs.
768  *
769  * Code mostly taken from arch/ia64/kernel/palinfo.c:cache_info().
770  */
771 static void __init set_pci_dfl_cacheline_size(void)
772 {
773 	unsigned long levels, unique_caches;
774 	long status;
775 	pal_cache_config_info_t cci;
776 
777 	status = ia64_pal_cache_summary(&levels, &unique_caches);
778 	if (status != 0) {
779 		pr_err("%s: ia64_pal_cache_summary() failed "
780 			"(status=%ld)\n", __func__, status);
781 		return;
782 	}
783 
784 	status = ia64_pal_cache_config_info(levels - 1,
785 				/* cache_type (data_or_unified)= */ 2, &cci);
786 	if (status != 0) {
787 		pr_err("%s: ia64_pal_cache_config_info() failed "
788 			"(status=%ld)\n", __func__, status);
789 		return;
790 	}
791 	pci_dfl_cache_line_size = (1 << cci.pcci_line_size) / 4;
792 }
793 
794 u64 ia64_dma_get_required_mask(struct device *dev)
795 {
796 	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
797 	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
798 	u64 mask;
799 
800 	if (!high_totalram) {
801 		/* convert to mask just covering totalram */
802 		low_totalram = (1 << (fls(low_totalram) - 1));
803 		low_totalram += low_totalram - 1;
804 		mask = low_totalram;
805 	} else {
806 		high_totalram = (1 << (fls(high_totalram) - 1));
807 		high_totalram += high_totalram - 1;
808 		mask = (((u64)high_totalram) << 32) + 0xffffffff;
809 	}
810 	return mask;
811 }
812 EXPORT_SYMBOL_GPL(ia64_dma_get_required_mask);
813 
814 u64 dma_get_required_mask(struct device *dev)
815 {
816 	return platform_dma_get_required_mask(dev);
817 }
818 EXPORT_SYMBOL_GPL(dma_get_required_mask);
819 
820 static int __init pcibios_init(void)
821 {
822 	set_pci_dfl_cacheline_size();
823 	return 0;
824 }
825 
826 subsys_initcall(pcibios_init);
827