1 /*
2  * pci.c - Low-Level PCI Access in IA-64
3  *
4  * Derived from bios32.c of i386 tree.
5  * Copyright (C) 2002, 2003 Hewlett-Packard Co
6  *	David Mosberger-Tang <davidm@hpl.hp.com>
7  *	Bjorn Helgaas <bjorn_helgaas@hp.com>
8  *
9  * Note: Above list of copyright holders is incomplete...
10  */
11 #include <linux/config.h>
12 
13 #include <linux/acpi.h>
14 #include <linux/types.h>
15 #include <linux/kernel.h>
16 #include <linux/pci.h>
17 #include <linux/init.h>
18 #include <linux/ioport.h>
19 #include <linux/slab.h>
20 #include <linux/smp_lock.h>
21 #include <linux/spinlock.h>
22 
23 #include <asm/machvec.h>
24 #include <asm/mca.h>
25 #include <asm/page.h>
26 #include <asm/segment.h>
27 #include <asm/system.h>
28 #include <asm/io.h>
29 
30 #include <asm/sal.h>
31 
32 
33 #ifdef CONFIG_SMP
34 # include <asm/smp.h>
35 #endif
36 #include <asm/irq.h>
37 
38 
39 #undef DEBUG
40 #define DEBUG
41 
42 #ifdef DEBUG
43 #define DBG(x...) printk(x)
44 #else
45 #define DBG(x...)
46 #endif
47 
48 struct pci_fixup pcibios_fixups[1];
49 
50 struct pci_ops *pci_root_ops;
51 
52 int (*pci_config_read)(int seg, int bus, int dev, int fn, int reg, int len, u32 *value);
53 int (*pci_config_write)(int seg, int bus, int dev, int fn, int reg, int len, u32 value);
54 
55 
56 /*
57  * Low-level SAL-based PCI configuration access functions. Note that SAL
58  * calls are already serialized (via sal_lock), so we don't need another
59  * synchronization mechanism here.
60  */
61 
62 #define PCI_SAL_ADDRESS(seg, bus, dev, fn, reg) \
63 	((u64)(seg << 24) | (u64)(bus << 16) | \
64 	 (u64)(dev << 11) | (u64)(fn << 8) | (u64)(reg))
65 
66 static int
pci_sal_read(int seg,int bus,int dev,int fn,int reg,int len,u32 * value)67 pci_sal_read (int seg, int bus, int dev, int fn, int reg, int len, u32 *value)
68 {
69 	int result = 0;
70 	u64 data = 0;
71 
72 	if (!value || (seg > 255) || (bus > 255) || (dev > 31) || (fn > 7) || (reg > 255))
73 		return -EINVAL;
74 
75 	result = ia64_sal_pci_config_read(PCI_SAL_ADDRESS(seg, bus, dev, fn, reg), len, &data);
76 
77 	*value = (u32) data;
78 
79 	return result;
80 }
81 
82 static int
pci_sal_write(int seg,int bus,int dev,int fn,int reg,int len,u32 value)83 pci_sal_write (int seg, int bus, int dev, int fn, int reg, int len, u32 value)
84 {
85 	if ((seg > 255) || (bus > 255) || (dev > 31) || (fn > 7) || (reg > 255))
86 		return -EINVAL;
87 
88 	return ia64_sal_pci_config_write(PCI_SAL_ADDRESS(seg, bus, dev, fn, reg), len, value);
89 }
90 
91 
92 static int
pci_sal_read_config_byte(struct pci_dev * dev,int where,u8 * value)93 pci_sal_read_config_byte (struct pci_dev *dev, int where, u8 *value)
94 {
95 	int result = 0;
96 	u32 data = 0;
97 
98 	if (!value)
99 		return -EINVAL;
100 
101 	result = pci_sal_read(PCI_SEGMENT(dev), dev->bus->number, PCI_SLOT(dev->devfn),
102 			      PCI_FUNC(dev->devfn), where, 1, &data);
103 
104 	*value = (u8) data;
105 
106 	return result;
107 }
108 
109 static int
pci_sal_read_config_word(struct pci_dev * dev,int where,u16 * value)110 pci_sal_read_config_word (struct pci_dev *dev, int where, u16 *value)
111 {
112 	int result = 0;
113 	u32 data = 0;
114 
115 	if (!value)
116 		return -EINVAL;
117 
118 	result = pci_sal_read(PCI_SEGMENT(dev), dev->bus->number, PCI_SLOT(dev->devfn),
119 			      PCI_FUNC(dev->devfn), where, 2, &data);
120 
121 	*value = (u16) data;
122 
123 	return result;
124 }
125 
126 static int
pci_sal_read_config_dword(struct pci_dev * dev,int where,u32 * value)127 pci_sal_read_config_dword (struct pci_dev *dev, int where, u32 *value)
128 {
129 	if (!value)
130 		return -EINVAL;
131 
132 	return pci_sal_read(PCI_SEGMENT(dev), dev->bus->number, PCI_SLOT(dev->devfn),
133 			    PCI_FUNC(dev->devfn), where, 4, value);
134 }
135 
136 static int
pci_sal_write_config_byte(struct pci_dev * dev,int where,u8 value)137 pci_sal_write_config_byte (struct pci_dev *dev, int where, u8 value)
138 {
139 	return pci_sal_write(PCI_SEGMENT(dev), dev->bus->number, PCI_SLOT(dev->devfn),
140 			     PCI_FUNC(dev->devfn), where, 1, value);
141 }
142 
143 static int
pci_sal_write_config_word(struct pci_dev * dev,int where,u16 value)144 pci_sal_write_config_word (struct pci_dev *dev, int where, u16 value)
145 {
146 	return pci_sal_write(PCI_SEGMENT(dev), dev->bus->number, PCI_SLOT(dev->devfn),
147 			     PCI_FUNC(dev->devfn), where, 2, value);
148 }
149 
150 static int
pci_sal_write_config_dword(struct pci_dev * dev,int where,u32 value)151 pci_sal_write_config_dword (struct pci_dev *dev, int where, u32 value)
152 {
153 	return pci_sal_write(PCI_SEGMENT(dev), dev->bus->number, PCI_SLOT(dev->devfn),
154 			     PCI_FUNC(dev->devfn), where, 4, value);
155 }
156 
157 struct pci_ops pci_sal_ops = {
158 	pci_sal_read_config_byte,
159 	pci_sal_read_config_word,
160 	pci_sal_read_config_dword,
161 	pci_sal_write_config_byte,
162 	pci_sal_write_config_word,
163 	pci_sal_write_config_dword
164 };
165 
166 
167 /*
168  * Initialization. Uses the SAL interface
169  */
170 
171 static struct pci_controller *
alloc_pci_controller(int seg)172 alloc_pci_controller (int seg)
173 {
174 	struct pci_controller *controller;
175 
176 	controller = kmalloc(sizeof(*controller), GFP_KERNEL);
177 	if (!controller)
178 		return NULL;
179 
180 	memset(controller, 0, sizeof(*controller));
181 	controller->segment = seg;
182 	return controller;
183 }
184 
185 static struct pci_bus *
scan_root_bus(int bus,struct pci_ops * ops,void * sysdata)186 scan_root_bus (int bus, struct pci_ops *ops, void *sysdata)
187 {
188 	struct pci_bus *b;
189 
190 	/*
191 	 * We know this is a new root bus we haven't seen before, so
192 	 * scan it, even if we've seen the same bus number in a different
193 	 * segment.
194 	 */
195 	b = kmalloc(sizeof(*b), GFP_KERNEL);
196 	if (!b)
197 		return NULL;
198 
199 	memset(b, 0, sizeof(*b));
200 	INIT_LIST_HEAD(&b->children);
201 	INIT_LIST_HEAD(&b->devices);
202 
203 	list_add_tail(&b->node, &pci_root_buses);
204 
205 	b->number = b->secondary = bus;
206 	b->resource[0] = &ioport_resource;
207 	b->resource[1] = &iomem_resource;
208 
209 	b->sysdata = sysdata;
210 	b->ops = ops;
211 	b->subordinate = pci_do_scan_bus(b);
212 
213 	return b;
214 }
215 
216 static int
alloc_resource(char * name,struct resource * root,unsigned long start,unsigned long end,unsigned long flags)217 alloc_resource (char *name, struct resource *root, unsigned long start, unsigned long end, unsigned long flags)
218 {
219 	struct resource *res;
220 
221 	res = kmalloc(sizeof(*res), GFP_KERNEL);
222 	if (!res)
223 		return -ENOMEM;
224 
225 	memset(res, 0, sizeof(*res));
226 	res->name = name;
227 	res->start = start;
228 	res->end = end;
229 	res->flags = flags;
230 
231 	if (request_resource(root, res))
232 		return -EBUSY;
233 
234 	return 0;
235 }
236 
237 static u64
add_io_space(struct acpi_resource_address64 * addr)238 add_io_space (struct acpi_resource_address64 *addr)
239 {
240 	u64 offset;
241 	int sparse = 0;
242 	int i;
243 
244 	if (addr->address_translation_offset == 0)
245 		return IO_SPACE_BASE(0);	/* part of legacy IO space */
246 
247 	if (addr->attribute.io.translation_attribute == ACPI_SPARSE_TRANSLATION)
248 		sparse = 1;
249 
250 	offset = (u64) ioremap(addr->address_translation_offset, 0);
251 	for (i = 0; i < num_io_spaces; i++)
252 		if (io_space[i].mmio_base == offset &&
253 		    io_space[i].sparse == sparse)
254 			return IO_SPACE_BASE(i);
255 
256 	if (num_io_spaces == MAX_IO_SPACES) {
257 		printk("Too many IO port spaces\n");
258 		return ~0;
259 	}
260 
261 	i = num_io_spaces++;
262 	io_space[i].mmio_base = offset;
263 	io_space[i].sparse = sparse;
264 
265 	return IO_SPACE_BASE(i);
266 }
267 
268 static acpi_status
count_window(struct acpi_resource * resource,void * data)269 count_window (struct acpi_resource *resource, void *data)
270 {
271 	unsigned int *windows = (unsigned int *) data;
272 	struct acpi_resource_address64 addr;
273 	acpi_status status;
274 
275 	status = acpi_resource_to_address64(resource, &addr);
276 	if (ACPI_SUCCESS(status))
277 		if (addr.resource_type == ACPI_MEMORY_RANGE ||
278 		    addr.resource_type == ACPI_IO_RANGE)
279 			(*windows)++;
280 
281 	return AE_OK;
282 }
283 
284 struct pci_root_info {
285 	struct pci_controller *controller;
286 	char *name;
287 };
288 
289 static acpi_status
add_window(struct acpi_resource * res,void * data)290 add_window (struct acpi_resource *res, void *data)
291 {
292 	struct pci_root_info *info = (struct pci_root_info *) data;
293 	struct pci_window *window;
294 	struct acpi_resource_address64 addr;
295 	acpi_status status;
296 	unsigned long flags, offset = 0;
297 	struct resource *root;
298 
299 	status = acpi_resource_to_address64(res, &addr);
300 	if (ACPI_SUCCESS(status)) {
301 		if (!addr.address_length)
302 			return AE_OK;
303 
304 		if (addr.resource_type == ACPI_MEMORY_RANGE) {
305 			flags = IORESOURCE_MEM;
306 			root = &iomem_resource;
307 			offset = addr.address_translation_offset;
308 		} else if (addr.resource_type == ACPI_IO_RANGE) {
309 			flags = IORESOURCE_IO;
310 			root = &ioport_resource;
311 			offset = add_io_space(&addr);
312 			if (offset == ~0)
313 				return AE_OK;
314 		} else
315 			return AE_OK;
316 
317 		window = &info->controller->window[info->controller->windows++];
318 		window->resource.flags |= flags;
319 		window->resource.start  = addr.min_address_range;
320 		window->resource.end    = addr.max_address_range;
321 		window->offset		= offset;
322 
323 		if (alloc_resource(info->name, root, addr.min_address_range + offset,
324 			addr.max_address_range + offset, flags))
325 			printk(KERN_ERR "alloc 0x%lx-0x%lx from %s for %s failed\n",
326 				addr.min_address_range + offset, addr.max_address_range + offset,
327 				root->name, info->name);
328 	}
329 
330 	return AE_OK;
331 }
332 
333 struct pci_bus *
pcibios_scan_root(void * handle,int seg,int bus)334 pcibios_scan_root (void *handle, int seg, int bus)
335 {
336 	struct pci_root_info info;
337 	struct pci_controller *controller;
338 	unsigned int windows = 0;
339 	char *name;
340 
341 	controller = alloc_pci_controller(seg);
342 	if (!controller)
343 		goto out1;
344 
345 	controller->acpi_handle = handle;
346 
347 	acpi_walk_resources(handle, METHOD_NAME__CRS, count_window, &windows);
348 	controller->window = kmalloc(sizeof(*controller->window) * windows, GFP_KERNEL);
349 	if (!controller->window)
350 		goto out2;
351 
352 	name = kmalloc(16, GFP_KERNEL);
353 	if (!name)
354 		goto out3;
355 
356 	sprintf(name, "PCI Bus %02x:%02x", seg, bus);
357 	info.controller = controller;
358 	info.name = name;
359 	acpi_walk_resources(handle, METHOD_NAME__CRS, add_window, &info);
360 
361 	return scan_root_bus(bus, pci_root_ops, controller);
362 
363 out3:
364 	kfree(controller->window);
365 out2:
366 	kfree(controller);
367 out1:
368 	return NULL;
369 }
370 
371 void __init
pcibios_config_init(void)372 pcibios_config_init (void)
373 {
374 	if (pci_root_ops)
375 		return;
376 
377 	printk("PCI: Using SAL to access configuration space\n");
378 
379 	pci_root_ops = &pci_sal_ops;
380 	pci_config_read = pci_sal_read;
381 	pci_config_write = pci_sal_write;
382 
383 	return;
384 }
385 
386 void __init
pcibios_init(void)387 pcibios_init (void)
388 {
389 	pcibios_config_init();
390 
391 	platform_pci_fixup(0);	/* phase 0 fixups (before buses scanned) */
392 
393 	platform_pci_fixup(1);	/* phase 1 fixups (after buses scanned) */
394 
395 	return;
396 }
397 
398 void __init
pcibios_fixup_device_resources(struct pci_dev * dev,struct pci_bus * bus)399 pcibios_fixup_device_resources (struct pci_dev *dev, struct pci_bus *bus)
400 {
401 	struct pci_controller *controller = PCI_CONTROLLER(dev);
402 	struct pci_window *window;
403 	int i, j;
404 
405 	for (i = 0; i < PCI_NUM_RESOURCES; i++) {
406 		if (!dev->resource[i].start)
407 			continue;
408 
409 #define contains(win, res)	((res)->start >= (win)->start && \
410 				 (res)->end   <= (win)->end)
411 
412 		for (j = 0; j < controller->windows; j++) {
413 			window = &controller->window[j];
414 			if (((dev->resource[i].flags & IORESOURCE_MEM &&
415 			      window->resource.flags & IORESOURCE_MEM) ||
416 			     (dev->resource[i].flags & IORESOURCE_IO &&
417 			      window->resource.flags & IORESOURCE_IO)) &&
418 			    contains(&window->resource, &dev->resource[i])) {
419 				dev->resource[i].start += window->offset;
420 				dev->resource[i].end   += window->offset;
421 			}
422 		}
423 	}
424 }
425 
426 /*
427  *  Called after each bus is probed, but before its children are examined.
428  */
429 void __devinit
pcibios_fixup_bus(struct pci_bus * b)430 pcibios_fixup_bus (struct pci_bus *b)
431 {
432 	struct list_head *ln;
433 
434 	for (ln = b->devices.next; ln != &b->devices; ln = ln->next)
435 		pcibios_fixup_device_resources(pci_dev_b(ln), b);
436 }
437 
438 void __devinit
pcibios_update_resource(struct pci_dev * dev,struct resource * root,struct resource * res,int resource)439 pcibios_update_resource (struct pci_dev *dev, struct resource *root,
440 			 struct resource *res, int resource)
441 {
442 	unsigned long where, size;
443 	u32 reg;
444 
445 	where = PCI_BASE_ADDRESS_0 + (resource * 4);
446 	size = res->end - res->start;
447 	pci_read_config_dword(dev, where, &reg);
448 	reg = (reg & size) | (((u32)(res->start - root->start)) & ~size);
449 	pci_write_config_dword(dev, where, reg);
450 
451 	/* ??? FIXME -- record old value for shutdown.  */
452 }
453 
454 void __devinit
pcibios_update_irq(struct pci_dev * dev,int irq)455 pcibios_update_irq (struct pci_dev *dev, int irq)
456 {
457 	pci_write_config_byte(dev, PCI_INTERRUPT_LINE, irq);
458 
459 	/* ??? FIXME -- record old value for shutdown.  */
460 }
461 
462 void __devinit
pcibios_fixup_pbus_ranges(struct pci_bus * bus,struct pbus_set_ranges_data * ranges)463 pcibios_fixup_pbus_ranges (struct pci_bus * bus, struct pbus_set_ranges_data * ranges)
464 {
465 	ranges->io_start -= bus->resource[0]->start;
466 	ranges->io_end -= bus->resource[0]->start;
467 	ranges->mem_start -= bus->resource[1]->start;
468 	ranges->mem_end -= bus->resource[1]->start;
469 }
470 
471 static inline int
pcibios_enable_resources(struct pci_dev * dev,int mask)472 pcibios_enable_resources (struct pci_dev *dev, int mask)
473 {
474 	u16 cmd, old_cmd;
475 	int idx;
476 	struct resource *r;
477 
478 	if (!dev)
479 		return -EINVAL;
480 
481 	pci_read_config_word(dev, PCI_COMMAND, &cmd);
482 	old_cmd = cmd;
483 	for (idx=0; idx<6; idx++) {
484 		/* Only set up the desired resources.  */
485 		if (!(mask & (1 << idx)))
486 			continue;
487 
488 		r = &dev->resource[idx];
489 		if (!r->start && r->end) {
490 			printk(KERN_ERR
491 			       "PCI: Device %s not available because of resource collisions\n",
492 			       dev->slot_name);
493 			return -EINVAL;
494 		}
495 		if (r->flags & IORESOURCE_IO)
496 			cmd |= PCI_COMMAND_IO;
497 		if (r->flags & IORESOURCE_MEM)
498 			cmd |= PCI_COMMAND_MEMORY;
499 	}
500 	if (dev->resource[PCI_ROM_RESOURCE].start)
501 		cmd |= PCI_COMMAND_MEMORY;
502 	if (cmd != old_cmd) {
503 		printk("PCI: Enabling device %s (%04x -> %04x)\n", dev->slot_name, old_cmd, cmd);
504 		pci_write_config_word(dev, PCI_COMMAND, cmd);
505 	}
506 	return 0;
507 }
508 
509 int
pcibios_enable_device(struct pci_dev * dev,int mask)510 pcibios_enable_device (struct pci_dev *dev, int mask)
511 {
512 	int ret;
513 
514 	ret = pcibios_enable_resources(dev, mask);
515 	if (ret < 0)
516 		return ret;
517 
518 	printk(KERN_INFO "PCI: Found IRQ %d for device %s\n", dev->irq, dev->slot_name);
519 
520 	return 0;
521 }
522 
523 void
pcibios_align_resource(void * data,struct resource * res,unsigned long size,unsigned long align)524 pcibios_align_resource (void *data, struct resource *res,
525 		        unsigned long size, unsigned long align)
526 {
527 }
528 
529 /*
530  * PCI BIOS setup, always defaults to SAL interface
531  */
532 char * __init
pcibios_setup(char * str)533 pcibios_setup (char *str)
534 {
535 	return NULL;
536 }
537 
538 int
pci_mmap_page_range(struct pci_dev * dev,struct vm_area_struct * vma,enum pci_mmap_state mmap_state,int write_combine)539 pci_mmap_page_range (struct pci_dev *dev, struct vm_area_struct *vma,
540 		     enum pci_mmap_state mmap_state, int write_combine)
541 {
542 	/*
543 	 * I/O space cannot be accessed via normal processor loads and stores on this
544 	 * platform.
545 	 */
546 	if (mmap_state == pci_mmap_io)
547 		/*
548 		 * XXX we could relax this for I/O spaces for which ACPI indicates that
549 		 * the space is 1-to-1 mapped.  But at the moment, we don't support
550 		 * multiple PCI address spaces and the legacy I/O space is not 1-to-1
551 		 * mapped, so this is moot.
552 		 */
553 		return -EINVAL;
554 
555 	/*
556 	 * Leave vm_pgoff as-is, the PCI space address is the physical address on this
557 	 * platform.
558 	 */
559 	vma->vm_flags |= (VM_SHM | VM_LOCKED | VM_IO);
560 
561 	if (write_combine)
562 		vma->vm_page_prot = pgprot_writecombine(vma->vm_page_prot);
563 	else
564 		vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
565 
566 	if (remap_page_range(vma->vm_start, vma->vm_pgoff << PAGE_SHIFT,
567 			     vma->vm_end - vma->vm_start, vma->vm_page_prot))
568 		return -EAGAIN;
569 
570 	return 0;
571 }
572 
573 /**
574  * pci_cacheline_size - determine cacheline size for PCI devices
575  * @dev: void
576  *
577  * We want to use the line-size of the outer-most cache.  We assume
578  * that this line-size is the same for all CPUs.
579  *
580  * Code mostly taken from arch/ia64/kernel/palinfo.c:cache_info().
581  *
582  * RETURNS: An appropriate -ERRNO error value on eror, or zero for success.
583  */
584 static unsigned long
pci_cacheline_size(void)585 pci_cacheline_size (void)
586 {
587 	u64 levels, unique_caches;
588 	s64 status;
589 	pal_cache_config_info_t cci;
590 	static u8 cacheline_size;
591 
592 	if (cacheline_size)
593 		return cacheline_size;
594 
595 	status = ia64_pal_cache_summary(&levels, &unique_caches);
596 	if (status != 0) {
597 		printk(KERN_ERR "%s: ia64_pal_cache_summary() failed (status=%ld)\n",
598 		       __FUNCTION__, status);
599 		return SMP_CACHE_BYTES;
600 	}
601 
602 	status = ia64_pal_cache_config_info(levels - 1, /* cache_type (data_or_unified)= */ 2,
603 					    &cci);
604 	if (status != 0) {
605 		printk(KERN_ERR "%s: ia64_pal_cache_config_info() failed (status=%ld)\n",
606 		       __FUNCTION__, status);
607 		return SMP_CACHE_BYTES;
608 	}
609 	cacheline_size = 1 << cci.pcci_line_size;
610 	return cacheline_size;
611 }
612 
613 /**
614  * pcibios_prep_mwi - helper function for drivers/pci/pci.c:pci_set_mwi()
615  * @dev: the PCI device for which MWI is enabled
616  *
617  * For ia64, we can get the cacheline sizes from PAL.
618  *
619  * RETURNS: An appropriate -ERRNO error value on eror, or zero for success.
620  */
621 int
pcibios_set_mwi(struct pci_dev * dev)622 pcibios_set_mwi (struct pci_dev *dev)
623 {
624 	unsigned long desired_linesize, current_linesize;
625 	int rc = 0;
626 	u8 pci_linesize;
627 
628 	desired_linesize = pci_cacheline_size();
629 
630 	pci_read_config_byte(dev, PCI_CACHE_LINE_SIZE, &pci_linesize);
631 	current_linesize = 4 * pci_linesize;
632 	if (desired_linesize != current_linesize) {
633 		printk(KERN_WARNING "PCI: slot %s has incorrect PCI cache line size of %lu bytes,",
634 		       dev->slot_name, current_linesize);
635 		if (current_linesize > desired_linesize) {
636 			printk(" expected %lu bytes instead\n", desired_linesize);
637 			rc = -EINVAL;
638 		} else {
639 			printk(" correcting to %lu\n", desired_linesize);
640 			pci_write_config_byte(dev, PCI_CACHE_LINE_SIZE, desired_linesize / 4);
641 		}
642 	}
643 	return rc;
644 }
645