xref: /openbmc/linux/arch/ia64/pci/pci.c (revision 7b6d864b)
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 	controller->node = -1;
130 	return controller;
131 }
132 
133 struct pci_root_info {
134 	struct acpi_device *bridge;
135 	struct pci_controller *controller;
136 	struct list_head resources;
137 	struct resource *res;
138 	resource_size_t *res_offset;
139 	unsigned int res_num;
140 	struct list_head io_resources;
141 	char *name;
142 };
143 
144 static unsigned int
145 new_space (u64 phys_base, int sparse)
146 {
147 	u64 mmio_base;
148 	int i;
149 
150 	if (phys_base == 0)
151 		return 0;	/* legacy I/O port space */
152 
153 	mmio_base = (u64) ioremap(phys_base, 0);
154 	for (i = 0; i < num_io_spaces; i++)
155 		if (io_space[i].mmio_base == mmio_base &&
156 		    io_space[i].sparse == sparse)
157 			return i;
158 
159 	if (num_io_spaces == MAX_IO_SPACES) {
160 		pr_err("PCI: Too many IO port spaces "
161 			"(MAX_IO_SPACES=%lu)\n", MAX_IO_SPACES);
162 		return ~0;
163 	}
164 
165 	i = num_io_spaces++;
166 	io_space[i].mmio_base = mmio_base;
167 	io_space[i].sparse = sparse;
168 
169 	return i;
170 }
171 
172 static u64 add_io_space(struct pci_root_info *info,
173 			struct acpi_resource_address64 *addr)
174 {
175 	struct iospace_resource *iospace;
176 	struct resource *resource;
177 	char *name;
178 	unsigned long base, min, max, base_port;
179 	unsigned int sparse = 0, space_nr, len;
180 
181 	len = strlen(info->name) + 32;
182 	iospace = kzalloc(sizeof(*iospace) + len, GFP_KERNEL);
183 	if (!iospace) {
184 		dev_err(&info->bridge->dev,
185 				"PCI: No memory for %s I/O port space\n",
186 				info->name);
187 		goto out;
188 	}
189 
190 	name = (char *)(iospace + 1);
191 
192 	min = addr->minimum;
193 	max = min + addr->address_length - 1;
194 	if (addr->info.io.translation_type == ACPI_SPARSE_TRANSLATION)
195 		sparse = 1;
196 
197 	space_nr = new_space(addr->translation_offset, sparse);
198 	if (space_nr == ~0)
199 		goto free_resource;
200 
201 	base = __pa(io_space[space_nr].mmio_base);
202 	base_port = IO_SPACE_BASE(space_nr);
203 	snprintf(name, len, "%s I/O Ports %08lx-%08lx", info->name,
204 		base_port + min, base_port + max);
205 
206 	/*
207 	 * The SDM guarantees the legacy 0-64K space is sparse, but if the
208 	 * mapping is done by the processor (not the bridge), ACPI may not
209 	 * mark it as sparse.
210 	 */
211 	if (space_nr == 0)
212 		sparse = 1;
213 
214 	resource = &iospace->res;
215 	resource->name  = name;
216 	resource->flags = IORESOURCE_MEM;
217 	resource->start = base + (sparse ? IO_SPACE_SPARSE_ENCODING(min) : min);
218 	resource->end   = base + (sparse ? IO_SPACE_SPARSE_ENCODING(max) : max);
219 	if (insert_resource(&iomem_resource, resource)) {
220 		dev_err(&info->bridge->dev,
221 				"can't allocate host bridge io space resource  %pR\n",
222 				resource);
223 		goto free_resource;
224 	}
225 
226 	list_add_tail(&iospace->list, &info->io_resources);
227 	return base_port;
228 
229 free_resource:
230 	kfree(iospace);
231 out:
232 	return ~0;
233 }
234 
235 static acpi_status resource_to_window(struct acpi_resource *resource,
236 				      struct acpi_resource_address64 *addr)
237 {
238 	acpi_status status;
239 
240 	/*
241 	 * We're only interested in _CRS descriptors that are
242 	 *	- address space descriptors for memory or I/O space
243 	 *	- non-zero size
244 	 *	- producers, i.e., the address space is routed downstream,
245 	 *	  not consumed by the bridge itself
246 	 */
247 	status = acpi_resource_to_address64(resource, addr);
248 	if (ACPI_SUCCESS(status) &&
249 	    (addr->resource_type == ACPI_MEMORY_RANGE ||
250 	     addr->resource_type == ACPI_IO_RANGE) &&
251 	    addr->address_length &&
252 	    addr->producer_consumer == ACPI_PRODUCER)
253 		return AE_OK;
254 
255 	return AE_ERROR;
256 }
257 
258 static acpi_status count_window(struct acpi_resource *resource, void *data)
259 {
260 	unsigned int *windows = (unsigned int *) data;
261 	struct acpi_resource_address64 addr;
262 	acpi_status status;
263 
264 	status = resource_to_window(resource, &addr);
265 	if (ACPI_SUCCESS(status))
266 		(*windows)++;
267 
268 	return AE_OK;
269 }
270 
271 static acpi_status add_window(struct acpi_resource *res, void *data)
272 {
273 	struct pci_root_info *info = data;
274 	struct resource *resource;
275 	struct acpi_resource_address64 addr;
276 	acpi_status status;
277 	unsigned long flags, offset = 0;
278 	struct resource *root;
279 
280 	/* Return AE_OK for non-window resources to keep scanning for more */
281 	status = resource_to_window(res, &addr);
282 	if (!ACPI_SUCCESS(status))
283 		return AE_OK;
284 
285 	if (addr.resource_type == ACPI_MEMORY_RANGE) {
286 		flags = IORESOURCE_MEM;
287 		root = &iomem_resource;
288 		offset = addr.translation_offset;
289 	} else if (addr.resource_type == ACPI_IO_RANGE) {
290 		flags = IORESOURCE_IO;
291 		root = &ioport_resource;
292 		offset = add_io_space(info, &addr);
293 		if (offset == ~0)
294 			return AE_OK;
295 	} else
296 		return AE_OK;
297 
298 	resource = &info->res[info->res_num];
299 	resource->name = info->name;
300 	resource->flags = flags;
301 	resource->start = addr.minimum + offset;
302 	resource->end = resource->start + addr.address_length - 1;
303 	info->res_offset[info->res_num] = offset;
304 
305 	if (insert_resource(root, resource)) {
306 		dev_err(&info->bridge->dev,
307 			"can't allocate host bridge window %pR\n",
308 			resource);
309 	} else {
310 		if (offset)
311 			dev_info(&info->bridge->dev, "host bridge window %pR "
312 				 "(PCI address [%#llx-%#llx])\n",
313 				 resource,
314 				 resource->start - offset,
315 				 resource->end - offset);
316 		else
317 			dev_info(&info->bridge->dev,
318 				 "host bridge window %pR\n", resource);
319 	}
320 	/* HP's firmware has a hack to work around a Windows bug.
321 	 * Ignore these tiny memory ranges */
322 	if (!((resource->flags & IORESOURCE_MEM) &&
323 	      (resource->end - resource->start < 16)))
324 		pci_add_resource_offset(&info->resources, resource,
325 					info->res_offset[info->res_num]);
326 
327 	info->res_num++;
328 	return AE_OK;
329 }
330 
331 static void free_pci_root_info_res(struct pci_root_info *info)
332 {
333 	struct iospace_resource *iospace, *tmp;
334 
335 	list_for_each_entry_safe(iospace, tmp, &info->io_resources, list)
336 		kfree(iospace);
337 
338 	kfree(info->name);
339 	kfree(info->res);
340 	info->res = NULL;
341 	kfree(info->res_offset);
342 	info->res_offset = NULL;
343 	info->res_num = 0;
344 	kfree(info->controller);
345 	info->controller = NULL;
346 }
347 
348 static void __release_pci_root_info(struct pci_root_info *info)
349 {
350 	int i;
351 	struct resource *res;
352 	struct iospace_resource *iospace;
353 
354 	list_for_each_entry(iospace, &info->io_resources, list)
355 		release_resource(&iospace->res);
356 
357 	for (i = 0; i < info->res_num; i++) {
358 		res = &info->res[i];
359 
360 		if (!res->parent)
361 			continue;
362 
363 		if (!(res->flags & (IORESOURCE_MEM | IORESOURCE_IO)))
364 			continue;
365 
366 		release_resource(res);
367 	}
368 
369 	free_pci_root_info_res(info);
370 	kfree(info);
371 }
372 
373 static void release_pci_root_info(struct pci_host_bridge *bridge)
374 {
375 	struct pci_root_info *info = bridge->release_data;
376 
377 	__release_pci_root_info(info);
378 }
379 
380 static int
381 probe_pci_root_info(struct pci_root_info *info, struct acpi_device *device,
382 		int busnum, int domain)
383 {
384 	char *name;
385 
386 	name = kmalloc(16, GFP_KERNEL);
387 	if (!name)
388 		return -ENOMEM;
389 
390 	sprintf(name, "PCI Bus %04x:%02x", domain, busnum);
391 	info->bridge = device;
392 	info->name = name;
393 
394 	acpi_walk_resources(device->handle, METHOD_NAME__CRS, count_window,
395 			&info->res_num);
396 	if (info->res_num) {
397 		info->res =
398 			kzalloc_node(sizeof(*info->res) * info->res_num,
399 				     GFP_KERNEL, info->controller->node);
400 		if (!info->res) {
401 			kfree(name);
402 			return -ENOMEM;
403 		}
404 
405 		info->res_offset =
406 			kzalloc_node(sizeof(*info->res_offset) * info->res_num,
407 					GFP_KERNEL, info->controller->node);
408 		if (!info->res_offset) {
409 			kfree(name);
410 			kfree(info->res);
411 			info->res = NULL;
412 			return -ENOMEM;
413 		}
414 
415 		info->res_num = 0;
416 		acpi_walk_resources(device->handle, METHOD_NAME__CRS,
417 			add_window, info);
418 	} else
419 		kfree(name);
420 
421 	return 0;
422 }
423 
424 struct pci_bus *pci_acpi_scan_root(struct acpi_pci_root *root)
425 {
426 	struct acpi_device *device = root->device;
427 	int domain = root->segment;
428 	int bus = root->secondary.start;
429 	struct pci_controller *controller;
430 	struct pci_root_info *info = NULL;
431 	int busnum = root->secondary.start;
432 	struct pci_bus *pbus;
433 	int pxm, ret;
434 
435 	controller = alloc_pci_controller(domain);
436 	if (!controller)
437 		return NULL;
438 
439 	controller->acpi_handle = device->handle;
440 
441 	pxm = acpi_get_pxm(controller->acpi_handle);
442 #ifdef CONFIG_NUMA
443 	if (pxm >= 0)
444 		controller->node = pxm_to_node(pxm);
445 #endif
446 
447 	info = kzalloc(sizeof(*info), GFP_KERNEL);
448 	if (!info) {
449 		dev_err(&device->dev,
450 				"pci_bus %04x:%02x: ignored (out of memory)\n",
451 				domain, busnum);
452 		kfree(controller);
453 		return NULL;
454 	}
455 
456 	info->controller = controller;
457 	INIT_LIST_HEAD(&info->io_resources);
458 	INIT_LIST_HEAD(&info->resources);
459 
460 	ret = probe_pci_root_info(info, device, busnum, domain);
461 	if (ret) {
462 		kfree(info->controller);
463 		kfree(info);
464 		return NULL;
465 	}
466 	/* insert busn resource at first */
467 	pci_add_resource(&info->resources, &root->secondary);
468 	/*
469 	 * See arch/x86/pci/acpi.c.
470 	 * The desired pci bus might already be scanned in a quirk. We
471 	 * should handle the case here, but it appears that IA64 hasn't
472 	 * such quirk. So we just ignore the case now.
473 	 */
474 	pbus = pci_create_root_bus(NULL, bus, &pci_root_ops, controller,
475 				   &info->resources);
476 	if (!pbus) {
477 		pci_free_resource_list(&info->resources);
478 		__release_pci_root_info(info);
479 		return NULL;
480 	}
481 
482 	pci_set_host_bridge_release(to_pci_host_bridge(pbus->bridge),
483 			release_pci_root_info, info);
484 	pci_scan_child_bus(pbus);
485 	return pbus;
486 }
487 
488 int pcibios_root_bridge_prepare(struct pci_host_bridge *bridge)
489 {
490 	struct pci_controller *controller = bridge->bus->sysdata;
491 
492 	ACPI_HANDLE_SET(&bridge->dev, controller->acpi_handle);
493 	return 0;
494 }
495 
496 static int is_valid_resource(struct pci_dev *dev, int idx)
497 {
498 	unsigned int i, type_mask = IORESOURCE_IO | IORESOURCE_MEM;
499 	struct resource *devr = &dev->resource[idx], *busr;
500 
501 	if (!dev->bus)
502 		return 0;
503 
504 	pci_bus_for_each_resource(dev->bus, busr, i) {
505 		if (!busr || ((busr->flags ^ devr->flags) & type_mask))
506 			continue;
507 		if ((devr->start) && (devr->start >= busr->start) &&
508 				(devr->end <= busr->end))
509 			return 1;
510 	}
511 	return 0;
512 }
513 
514 static void pcibios_fixup_resources(struct pci_dev *dev, int start, int limit)
515 {
516 	int i;
517 
518 	for (i = start; i < limit; i++) {
519 		if (!dev->resource[i].flags)
520 			continue;
521 		if ((is_valid_resource(dev, i)))
522 			pci_claim_resource(dev, i);
523 	}
524 }
525 
526 void pcibios_fixup_device_resources(struct pci_dev *dev)
527 {
528 	pcibios_fixup_resources(dev, 0, PCI_BRIDGE_RESOURCES);
529 }
530 EXPORT_SYMBOL_GPL(pcibios_fixup_device_resources);
531 
532 static void pcibios_fixup_bridge_resources(struct pci_dev *dev)
533 {
534 	pcibios_fixup_resources(dev, PCI_BRIDGE_RESOURCES, PCI_NUM_RESOURCES);
535 }
536 
537 /*
538  *  Called after each bus is probed, but before its children are examined.
539  */
540 void pcibios_fixup_bus(struct pci_bus *b)
541 {
542 	struct pci_dev *dev;
543 
544 	if (b->self) {
545 		pci_read_bridge_bases(b);
546 		pcibios_fixup_bridge_resources(b->self);
547 	}
548 	list_for_each_entry(dev, &b->devices, bus_list)
549 		pcibios_fixup_device_resources(dev);
550 	platform_pci_fixup_bus(b);
551 }
552 
553 void pcibios_add_bus(struct pci_bus *bus)
554 {
555 	acpi_pci_add_bus(bus);
556 }
557 
558 void pcibios_remove_bus(struct pci_bus *bus)
559 {
560 	acpi_pci_remove_bus(bus);
561 }
562 
563 void pcibios_set_master (struct pci_dev *dev)
564 {
565 	/* No special bus mastering setup handling */
566 }
567 
568 int
569 pcibios_enable_device (struct pci_dev *dev, int mask)
570 {
571 	int ret;
572 
573 	ret = pci_enable_resources(dev, mask);
574 	if (ret < 0)
575 		return ret;
576 
577 	if (!dev->msi_enabled)
578 		return acpi_pci_irq_enable(dev);
579 	return 0;
580 }
581 
582 void
583 pcibios_disable_device (struct pci_dev *dev)
584 {
585 	BUG_ON(atomic_read(&dev->enable_cnt));
586 	if (!dev->msi_enabled)
587 		acpi_pci_irq_disable(dev);
588 }
589 
590 resource_size_t
591 pcibios_align_resource (void *data, const struct resource *res,
592 		        resource_size_t size, resource_size_t align)
593 {
594 	return res->start;
595 }
596 
597 int
598 pci_mmap_page_range (struct pci_dev *dev, struct vm_area_struct *vma,
599 		     enum pci_mmap_state mmap_state, int write_combine)
600 {
601 	unsigned long size = vma->vm_end - vma->vm_start;
602 	pgprot_t prot;
603 
604 	/*
605 	 * I/O space cannot be accessed via normal processor loads and
606 	 * stores on this platform.
607 	 */
608 	if (mmap_state == pci_mmap_io)
609 		/*
610 		 * XXX we could relax this for I/O spaces for which ACPI
611 		 * indicates that the space is 1-to-1 mapped.  But at the
612 		 * moment, we don't support multiple PCI address spaces and
613 		 * the legacy I/O space is not 1-to-1 mapped, so this is moot.
614 		 */
615 		return -EINVAL;
616 
617 	if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size))
618 		return -EINVAL;
619 
620 	prot = phys_mem_access_prot(NULL, vma->vm_pgoff, size,
621 				    vma->vm_page_prot);
622 
623 	/*
624 	 * If the user requested WC, the kernel uses UC or WC for this region,
625 	 * and the chipset supports WC, we can use WC. Otherwise, we have to
626 	 * use the same attribute the kernel uses.
627 	 */
628 	if (write_combine &&
629 	    ((pgprot_val(prot) & _PAGE_MA_MASK) == _PAGE_MA_UC ||
630 	     (pgprot_val(prot) & _PAGE_MA_MASK) == _PAGE_MA_WC) &&
631 	    efi_range_is_wc(vma->vm_start, vma->vm_end - vma->vm_start))
632 		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
633 	else
634 		vma->vm_page_prot = prot;
635 
636 	if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
637 			     vma->vm_end - vma->vm_start, vma->vm_page_prot))
638 		return -EAGAIN;
639 
640 	return 0;
641 }
642 
643 /**
644  * ia64_pci_get_legacy_mem - generic legacy mem routine
645  * @bus: bus to get legacy memory base address for
646  *
647  * Find the base of legacy memory for @bus.  This is typically the first
648  * megabyte of bus address space for @bus or is simply 0 on platforms whose
649  * chipsets support legacy I/O and memory routing.  Returns the base address
650  * or an error pointer if an error occurred.
651  *
652  * This is the ia64 generic version of this routine.  Other platforms
653  * are free to override it with a machine vector.
654  */
655 char *ia64_pci_get_legacy_mem(struct pci_bus *bus)
656 {
657 	return (char *)__IA64_UNCACHED_OFFSET;
658 }
659 
660 /**
661  * pci_mmap_legacy_page_range - map legacy memory space to userland
662  * @bus: bus whose legacy space we're mapping
663  * @vma: vma passed in by mmap
664  *
665  * Map legacy memory space for this device back to userspace using a machine
666  * vector to get the base address.
667  */
668 int
669 pci_mmap_legacy_page_range(struct pci_bus *bus, struct vm_area_struct *vma,
670 			   enum pci_mmap_state mmap_state)
671 {
672 	unsigned long size = vma->vm_end - vma->vm_start;
673 	pgprot_t prot;
674 	char *addr;
675 
676 	/* We only support mmap'ing of legacy memory space */
677 	if (mmap_state != pci_mmap_mem)
678 		return -ENOSYS;
679 
680 	/*
681 	 * Avoid attribute aliasing.  See Documentation/ia64/aliasing.txt
682 	 * for more details.
683 	 */
684 	if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size))
685 		return -EINVAL;
686 	prot = phys_mem_access_prot(NULL, vma->vm_pgoff, size,
687 				    vma->vm_page_prot);
688 
689 	addr = pci_get_legacy_mem(bus);
690 	if (IS_ERR(addr))
691 		return PTR_ERR(addr);
692 
693 	vma->vm_pgoff += (unsigned long)addr >> PAGE_SHIFT;
694 	vma->vm_page_prot = prot;
695 
696 	if (remap_pfn_range(vma, vma->vm_start, vma->vm_pgoff,
697 			    size, vma->vm_page_prot))
698 		return -EAGAIN;
699 
700 	return 0;
701 }
702 
703 /**
704  * ia64_pci_legacy_read - read from legacy I/O space
705  * @bus: bus to read
706  * @port: legacy port value
707  * @val: caller allocated storage for returned value
708  * @size: number of bytes to read
709  *
710  * Simply reads @size bytes from @port and puts the result in @val.
711  *
712  * Again, this (and the write routine) are generic versions that can be
713  * overridden by the platform.  This is necessary on platforms that don't
714  * support legacy I/O routing or that hard fail on legacy I/O timeouts.
715  */
716 int ia64_pci_legacy_read(struct pci_bus *bus, u16 port, u32 *val, u8 size)
717 {
718 	int ret = size;
719 
720 	switch (size) {
721 	case 1:
722 		*val = inb(port);
723 		break;
724 	case 2:
725 		*val = inw(port);
726 		break;
727 	case 4:
728 		*val = inl(port);
729 		break;
730 	default:
731 		ret = -EINVAL;
732 		break;
733 	}
734 
735 	return ret;
736 }
737 
738 /**
739  * ia64_pci_legacy_write - perform a legacy I/O write
740  * @bus: bus pointer
741  * @port: port to write
742  * @val: value to write
743  * @size: number of bytes to write from @val
744  *
745  * Simply writes @size bytes of @val to @port.
746  */
747 int ia64_pci_legacy_write(struct pci_bus *bus, u16 port, u32 val, u8 size)
748 {
749 	int ret = size;
750 
751 	switch (size) {
752 	case 1:
753 		outb(val, port);
754 		break;
755 	case 2:
756 		outw(val, port);
757 		break;
758 	case 4:
759 		outl(val, port);
760 		break;
761 	default:
762 		ret = -EINVAL;
763 		break;
764 	}
765 
766 	return ret;
767 }
768 
769 /**
770  * set_pci_cacheline_size - determine cacheline size for PCI devices
771  *
772  * We want to use the line-size of the outer-most cache.  We assume
773  * that this line-size is the same for all CPUs.
774  *
775  * Code mostly taken from arch/ia64/kernel/palinfo.c:cache_info().
776  */
777 static void __init set_pci_dfl_cacheline_size(void)
778 {
779 	unsigned long levels, unique_caches;
780 	long status;
781 	pal_cache_config_info_t cci;
782 
783 	status = ia64_pal_cache_summary(&levels, &unique_caches);
784 	if (status != 0) {
785 		pr_err("%s: ia64_pal_cache_summary() failed "
786 			"(status=%ld)\n", __func__, status);
787 		return;
788 	}
789 
790 	status = ia64_pal_cache_config_info(levels - 1,
791 				/* cache_type (data_or_unified)= */ 2, &cci);
792 	if (status != 0) {
793 		pr_err("%s: ia64_pal_cache_config_info() failed "
794 			"(status=%ld)\n", __func__, status);
795 		return;
796 	}
797 	pci_dfl_cache_line_size = (1 << cci.pcci_line_size) / 4;
798 }
799 
800 u64 ia64_dma_get_required_mask(struct device *dev)
801 {
802 	u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
803 	u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
804 	u64 mask;
805 
806 	if (!high_totalram) {
807 		/* convert to mask just covering totalram */
808 		low_totalram = (1 << (fls(low_totalram) - 1));
809 		low_totalram += low_totalram - 1;
810 		mask = low_totalram;
811 	} else {
812 		high_totalram = (1 << (fls(high_totalram) - 1));
813 		high_totalram += high_totalram - 1;
814 		mask = (((u64)high_totalram) << 32) + 0xffffffff;
815 	}
816 	return mask;
817 }
818 EXPORT_SYMBOL_GPL(ia64_dma_get_required_mask);
819 
820 u64 dma_get_required_mask(struct device *dev)
821 {
822 	return platform_dma_get_required_mask(dev);
823 }
824 EXPORT_SYMBOL_GPL(dma_get_required_mask);
825 
826 static int __init pcibios_init(void)
827 {
828 	set_pci_dfl_cacheline_size();
829 	return 0;
830 }
831 
832 subsys_initcall(pcibios_init);
833