xref: /linux/arch/powerpc/kernel/pci_32.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
1 /*
2  * Common pmac/prep/chrp pci routines. -- Cort
3  */
4 
5 #include <linux/kernel.h>
6 #include <linux/pci.h>
7 #include <linux/delay.h>
8 #include <linux/string.h>
9 #include <linux/init.h>
10 #include <linux/capability.h>
11 #include <linux/sched.h>
12 #include <linux/errno.h>
13 #include <linux/bootmem.h>
14 #include <linux/irq.h>
15 #include <linux/list.h>
16 #include <linux/of.h>
17 
18 #include <asm/processor.h>
19 #include <asm/io.h>
20 #include <asm/prom.h>
21 #include <asm/sections.h>
22 #include <asm/pci-bridge.h>
23 #include <asm/ppc-pci.h>
24 #include <asm/byteorder.h>
25 #include <asm/uaccess.h>
26 #include <asm/machdep.h>
27 
28 #undef DEBUG
29 
30 unsigned long isa_io_base     = 0;
31 unsigned long pci_dram_offset = 0;
32 int pcibios_assign_bus_offset = 1;
33 
34 void pcibios_make_OF_bus_map(void);
35 
36 static void fixup_cpc710_pci64(struct pci_dev* dev);
37 #ifdef CONFIG_PPC_OF
38 static u8* pci_to_OF_bus_map;
39 #endif
40 
41 /* By default, we don't re-assign bus numbers. We do this only on
42  * some pmacs
43  */
44 static int pci_assign_all_buses;
45 
46 static int pci_bus_count;
47 
48 /* This will remain NULL for now, until isa-bridge.c is made common
49  * to both 32-bit and 64-bit.
50  */
51 struct pci_dev *isa_bridge_pcidev;
52 EXPORT_SYMBOL_GPL(isa_bridge_pcidev);
53 
54 static void
55 fixup_hide_host_resource_fsl(struct pci_dev *dev)
56 {
57 	int i, class = dev->class >> 8;
58 
59 	if ((class == PCI_CLASS_PROCESSOR_POWERPC ||
60 	     class == PCI_CLASS_BRIDGE_OTHER) &&
61 		(dev->hdr_type == PCI_HEADER_TYPE_NORMAL) &&
62 		(dev->bus->parent == NULL)) {
63 		for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
64 			dev->resource[i].start = 0;
65 			dev->resource[i].end = 0;
66 			dev->resource[i].flags = 0;
67 		}
68 	}
69 }
70 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_MOTOROLA, PCI_ANY_ID, fixup_hide_host_resource_fsl);
71 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_FREESCALE, PCI_ANY_ID, fixup_hide_host_resource_fsl);
72 
73 static void
74 fixup_cpc710_pci64(struct pci_dev* dev)
75 {
76 	/* Hide the PCI64 BARs from the kernel as their content doesn't
77 	 * fit well in the resource management
78 	 */
79 	dev->resource[0].start = dev->resource[0].end = 0;
80 	dev->resource[0].flags = 0;
81 	dev->resource[1].start = dev->resource[1].end = 0;
82 	dev->resource[1].flags = 0;
83 }
84 DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_IBM,	PCI_DEVICE_ID_IBM_CPC710_PCI64,	fixup_cpc710_pci64);
85 
86 #ifdef CONFIG_PPC_OF
87 /*
88  * Functions below are used on OpenFirmware machines.
89  */
90 static void
91 make_one_node_map(struct device_node* node, u8 pci_bus)
92 {
93 	const int *bus_range;
94 	int len;
95 
96 	if (pci_bus >= pci_bus_count)
97 		return;
98 	bus_range = of_get_property(node, "bus-range", &len);
99 	if (bus_range == NULL || len < 2 * sizeof(int)) {
100 		printk(KERN_WARNING "Can't get bus-range for %s, "
101 		       "assuming it starts at 0\n", node->full_name);
102 		pci_to_OF_bus_map[pci_bus] = 0;
103 	} else
104 		pci_to_OF_bus_map[pci_bus] = bus_range[0];
105 
106 	for_each_child_of_node(node, node) {
107 		struct pci_dev* dev;
108 		const unsigned int *class_code, *reg;
109 
110 		class_code = of_get_property(node, "class-code", NULL);
111 		if (!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
112 			(*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS))
113 			continue;
114 		reg = of_get_property(node, "reg", NULL);
115 		if (!reg)
116 			continue;
117 		dev = pci_get_bus_and_slot(pci_bus, ((reg[0] >> 8) & 0xff));
118 		if (!dev || !dev->subordinate) {
119 			pci_dev_put(dev);
120 			continue;
121 		}
122 		make_one_node_map(node, dev->subordinate->number);
123 		pci_dev_put(dev);
124 	}
125 }
126 
127 void
128 pcibios_make_OF_bus_map(void)
129 {
130 	int i;
131 	struct pci_controller *hose, *tmp;
132 	struct property *map_prop;
133 	struct device_node *dn;
134 
135 	pci_to_OF_bus_map = kmalloc(pci_bus_count, GFP_KERNEL);
136 	if (!pci_to_OF_bus_map) {
137 		printk(KERN_ERR "Can't allocate OF bus map !\n");
138 		return;
139 	}
140 
141 	/* We fill the bus map with invalid values, that helps
142 	 * debugging.
143 	 */
144 	for (i=0; i<pci_bus_count; i++)
145 		pci_to_OF_bus_map[i] = 0xff;
146 
147 	/* For each hose, we begin searching bridges */
148 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
149 		struct device_node* node = hose->dn;
150 
151 		if (!node)
152 			continue;
153 		make_one_node_map(node, hose->first_busno);
154 	}
155 	dn = of_find_node_by_path("/");
156 	map_prop = of_find_property(dn, "pci-OF-bus-map", NULL);
157 	if (map_prop) {
158 		BUG_ON(pci_bus_count > map_prop->length);
159 		memcpy(map_prop->value, pci_to_OF_bus_map, pci_bus_count);
160 	}
161 	of_node_put(dn);
162 #ifdef DEBUG
163 	printk("PCI->OF bus map:\n");
164 	for (i=0; i<pci_bus_count; i++) {
165 		if (pci_to_OF_bus_map[i] == 0xff)
166 			continue;
167 		printk("%d -> %d\n", i, pci_to_OF_bus_map[i]);
168 	}
169 #endif
170 }
171 
172 typedef int (*pci_OF_scan_iterator)(struct device_node* node, void* data);
173 
174 static struct device_node*
175 scan_OF_pci_childs(struct device_node *parent, pci_OF_scan_iterator filter, void* data)
176 {
177 	struct device_node *node;
178 	struct device_node* sub_node;
179 
180 	for_each_child_of_node(parent, node) {
181 		const unsigned int *class_code;
182 
183 		if (filter(node, data)) {
184 			of_node_put(node);
185 			return node;
186 		}
187 
188 		/* For PCI<->PCI bridges or CardBus bridges, we go down
189 		 * Note: some OFs create a parent node "multifunc-device" as
190 		 * a fake root for all functions of a multi-function device,
191 		 * we go down them as well.
192 		 */
193 		class_code = of_get_property(node, "class-code", NULL);
194 		if ((!class_code || ((*class_code >> 8) != PCI_CLASS_BRIDGE_PCI &&
195 			(*class_code >> 8) != PCI_CLASS_BRIDGE_CARDBUS)) &&
196 			strcmp(node->name, "multifunc-device"))
197 			continue;
198 		sub_node = scan_OF_pci_childs(node, filter, data);
199 		if (sub_node) {
200 			of_node_put(node);
201 			return sub_node;
202 		}
203 	}
204 	return NULL;
205 }
206 
207 static struct device_node *scan_OF_for_pci_dev(struct device_node *parent,
208 					       unsigned int devfn)
209 {
210 	struct device_node *np, *cnp;
211 	const u32 *reg;
212 	unsigned int psize;
213 
214 	for_each_child_of_node(parent, np) {
215 		reg = of_get_property(np, "reg", &psize);
216                 if (reg && psize >= 4 && ((reg[0] >> 8) & 0xff) == devfn)
217 			return np;
218 
219 		/* Note: some OFs create a parent node "multifunc-device" as
220 		 * a fake root for all functions of a multi-function device,
221 		 * we go down them as well. */
222                 if (!strcmp(np->name, "multifunc-device")) {
223                         cnp = scan_OF_for_pci_dev(np, devfn);
224                         if (cnp)
225                                 return cnp;
226                 }
227 	}
228 	return NULL;
229 }
230 
231 
232 static struct device_node *scan_OF_for_pci_bus(struct pci_bus *bus)
233 {
234 	struct device_node *parent, *np;
235 
236 	/* Are we a root bus ? */
237 	if (bus->self == NULL || bus->parent == NULL) {
238 		struct pci_controller *hose = pci_bus_to_host(bus);
239 		if (hose == NULL)
240 			return NULL;
241 		return of_node_get(hose->dn);
242 	}
243 
244 	/* not a root bus, we need to get our parent */
245 	parent = scan_OF_for_pci_bus(bus->parent);
246 	if (parent == NULL)
247 		return NULL;
248 
249 	/* now iterate for children for a match */
250 	np = scan_OF_for_pci_dev(parent, bus->self->devfn);
251 	of_node_put(parent);
252 
253 	return np;
254 }
255 
256 /*
257  * Scans the OF tree for a device node matching a PCI device
258  */
259 struct device_node *
260 pci_busdev_to_OF_node(struct pci_bus *bus, int devfn)
261 {
262 	struct device_node *parent, *np;
263 
264 	pr_debug("pci_busdev_to_OF_node(%d,0x%x)\n", bus->number, devfn);
265 	parent = scan_OF_for_pci_bus(bus);
266 	if (parent == NULL)
267 		return NULL;
268 	pr_debug(" parent is %s\n", parent ? parent->full_name : "<NULL>");
269 	np = scan_OF_for_pci_dev(parent, devfn);
270 	of_node_put(parent);
271 	pr_debug(" result is %s\n", np ? np->full_name : "<NULL>");
272 
273 	/* XXX most callers don't release the returned node
274 	 * mostly because ppc64 doesn't increase the refcount,
275 	 * we need to fix that.
276 	 */
277 	return np;
278 }
279 EXPORT_SYMBOL(pci_busdev_to_OF_node);
280 
281 struct device_node*
282 pci_device_to_OF_node(struct pci_dev *dev)
283 {
284 	return pci_busdev_to_OF_node(dev->bus, dev->devfn);
285 }
286 EXPORT_SYMBOL(pci_device_to_OF_node);
287 
288 static int
289 find_OF_pci_device_filter(struct device_node* node, void* data)
290 {
291 	return ((void *)node == data);
292 }
293 
294 /*
295  * Returns the PCI device matching a given OF node
296  */
297 int
298 pci_device_from_OF_node(struct device_node* node, u8* bus, u8* devfn)
299 {
300 	const unsigned int *reg;
301 	struct pci_controller* hose;
302 	struct pci_dev* dev = NULL;
303 
304 	/* Make sure it's really a PCI device */
305 	hose = pci_find_hose_for_OF_device(node);
306 	if (!hose || !hose->dn)
307 		return -ENODEV;
308 	if (!scan_OF_pci_childs(hose->dn,
309 			find_OF_pci_device_filter, (void *)node))
310 		return -ENODEV;
311 	reg = of_get_property(node, "reg", NULL);
312 	if (!reg)
313 		return -ENODEV;
314 	*bus = (reg[0] >> 16) & 0xff;
315 	*devfn = ((reg[0] >> 8) & 0xff);
316 
317 	/* Ok, here we need some tweak. If we have already renumbered
318 	 * all busses, we can't rely on the OF bus number any more.
319 	 * the pci_to_OF_bus_map is not enough as several PCI busses
320 	 * may match the same OF bus number.
321 	 */
322 	if (!pci_to_OF_bus_map)
323 		return 0;
324 
325 	for_each_pci_dev(dev)
326 		if (pci_to_OF_bus_map[dev->bus->number] == *bus &&
327 				dev->devfn == *devfn) {
328 			*bus = dev->bus->number;
329 			pci_dev_put(dev);
330 			return 0;
331 		}
332 
333 	return -ENODEV;
334 }
335 EXPORT_SYMBOL(pci_device_from_OF_node);
336 
337 /* We create the "pci-OF-bus-map" property now so it appears in the
338  * /proc device tree
339  */
340 void __init
341 pci_create_OF_bus_map(void)
342 {
343 	struct property* of_prop;
344 	struct device_node *dn;
345 
346 	of_prop = (struct property*) alloc_bootmem(sizeof(struct property) + 256);
347 	if (!of_prop)
348 		return;
349 	dn = of_find_node_by_path("/");
350 	if (dn) {
351 		memset(of_prop, -1, sizeof(struct property) + 256);
352 		of_prop->name = "pci-OF-bus-map";
353 		of_prop->length = 256;
354 		of_prop->value = &of_prop[1];
355 		prom_add_property(dn, of_prop);
356 		of_node_put(dn);
357 	}
358 }
359 
360 #else /* CONFIG_PPC_OF */
361 void pcibios_make_OF_bus_map(void)
362 {
363 }
364 #endif /* CONFIG_PPC_OF */
365 
366 static void __devinit pcibios_scan_phb(struct pci_controller *hose)
367 {
368 	struct pci_bus *bus;
369 	struct device_node *node = hose->dn;
370 	unsigned long io_offset;
371 	struct resource *res = &hose->io_resource;
372 
373 	pr_debug("PCI: Scanning PHB %s\n",
374 		 node ? node->full_name : "<NO NAME>");
375 
376 	/* Create an empty bus for the toplevel */
377 	bus = pci_create_bus(hose->parent, hose->first_busno, hose->ops, hose);
378 	if (bus == NULL) {
379 		printk(KERN_ERR "Failed to create bus for PCI domain %04x\n",
380 		       hose->global_number);
381 		return;
382 	}
383 	bus->secondary = hose->first_busno;
384 	hose->bus = bus;
385 
386 	/* Fixup IO space offset */
387 	io_offset = (unsigned long)hose->io_base_virt - isa_io_base;
388 	res->start = (res->start + io_offset) & 0xffffffffu;
389 	res->end = (res->end + io_offset) & 0xffffffffu;
390 
391 	/* Wire up PHB bus resources */
392 	pcibios_setup_phb_resources(hose);
393 
394 	/* Scan children */
395 	hose->last_busno = bus->subordinate = pci_scan_child_bus(bus);
396 }
397 
398 static int __init pcibios_init(void)
399 {
400 	struct pci_controller *hose, *tmp;
401 	int next_busno = 0;
402 
403 	printk(KERN_INFO "PCI: Probing PCI hardware\n");
404 
405 	if (ppc_pci_flags & PPC_PCI_REASSIGN_ALL_BUS)
406 		pci_assign_all_buses = 1;
407 
408 	/* Scan all of the recorded PCI controllers.  */
409 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node) {
410 		if (pci_assign_all_buses)
411 			hose->first_busno = next_busno;
412 		hose->last_busno = 0xff;
413 		pcibios_scan_phb(hose);
414 		pci_bus_add_devices(hose->bus);
415 		if (pci_assign_all_buses || next_busno <= hose->last_busno)
416 			next_busno = hose->last_busno + pcibios_assign_bus_offset;
417 	}
418 	pci_bus_count = next_busno;
419 
420 	/* OpenFirmware based machines need a map of OF bus
421 	 * numbers vs. kernel bus numbers since we may have to
422 	 * remap them.
423 	 */
424 	if (pci_assign_all_buses)
425 		pcibios_make_OF_bus_map();
426 
427 	/* Call common code to handle resource allocation */
428 	pcibios_resource_survey();
429 
430 	/* Call machine dependent post-init code */
431 	if (ppc_md.pcibios_after_init)
432 		ppc_md.pcibios_after_init();
433 
434 	return 0;
435 }
436 
437 subsys_initcall(pcibios_init);
438 
439 static struct pci_controller*
440 pci_bus_to_hose(int bus)
441 {
442 	struct pci_controller *hose, *tmp;
443 
444 	list_for_each_entry_safe(hose, tmp, &hose_list, list_node)
445 		if (bus >= hose->first_busno && bus <= hose->last_busno)
446 			return hose;
447 	return NULL;
448 }
449 
450 /* Provide information on locations of various I/O regions in physical
451  * memory.  Do this on a per-card basis so that we choose the right
452  * root bridge.
453  * Note that the returned IO or memory base is a physical address
454  */
455 
456 long sys_pciconfig_iobase(long which, unsigned long bus, unsigned long devfn)
457 {
458 	struct pci_controller* hose;
459 	long result = -EOPNOTSUPP;
460 
461 	hose = pci_bus_to_hose(bus);
462 	if (!hose)
463 		return -ENODEV;
464 
465 	switch (which) {
466 	case IOBASE_BRIDGE_NUMBER:
467 		return (long)hose->first_busno;
468 	case IOBASE_MEMORY:
469 		return (long)hose->pci_mem_offset;
470 	case IOBASE_IO:
471 		return (long)hose->io_base_phys;
472 	case IOBASE_ISA_IO:
473 		return (long)isa_io_base;
474 	case IOBASE_ISA_MEM:
475 		return (long)isa_mem_base;
476 	}
477 
478 	return result;
479 }
480 
481 /*
482  * Null PCI config access functions, for the case when we can't
483  * find a hose.
484  */
485 #define NULL_PCI_OP(rw, size, type)					\
486 static int								\
487 null_##rw##_config_##size(struct pci_dev *dev, int offset, type val)	\
488 {									\
489 	return PCIBIOS_DEVICE_NOT_FOUND;    				\
490 }
491 
492 static int
493 null_read_config(struct pci_bus *bus, unsigned int devfn, int offset,
494 		 int len, u32 *val)
495 {
496 	return PCIBIOS_DEVICE_NOT_FOUND;
497 }
498 
499 static int
500 null_write_config(struct pci_bus *bus, unsigned int devfn, int offset,
501 		  int len, u32 val)
502 {
503 	return PCIBIOS_DEVICE_NOT_FOUND;
504 }
505 
506 static struct pci_ops null_pci_ops =
507 {
508 	.read = null_read_config,
509 	.write = null_write_config,
510 };
511 
512 /*
513  * These functions are used early on before PCI scanning is done
514  * and all of the pci_dev and pci_bus structures have been created.
515  */
516 static struct pci_bus *
517 fake_pci_bus(struct pci_controller *hose, int busnr)
518 {
519 	static struct pci_bus bus;
520 
521 	if (hose == 0) {
522 		hose = pci_bus_to_hose(busnr);
523 		if (hose == 0)
524 			printk(KERN_ERR "Can't find hose for PCI bus %d!\n", busnr);
525 	}
526 	bus.number = busnr;
527 	bus.sysdata = hose;
528 	bus.ops = hose? hose->ops: &null_pci_ops;
529 	return &bus;
530 }
531 
532 #define EARLY_PCI_OP(rw, size, type)					\
533 int early_##rw##_config_##size(struct pci_controller *hose, int bus,	\
534 			       int devfn, int offset, type value)	\
535 {									\
536 	return pci_bus_##rw##_config_##size(fake_pci_bus(hose, bus),	\
537 					    devfn, offset, value);	\
538 }
539 
540 EARLY_PCI_OP(read, byte, u8 *)
541 EARLY_PCI_OP(read, word, u16 *)
542 EARLY_PCI_OP(read, dword, u32 *)
543 EARLY_PCI_OP(write, byte, u8)
544 EARLY_PCI_OP(write, word, u16)
545 EARLY_PCI_OP(write, dword, u32)
546 
547 extern int pci_bus_find_capability (struct pci_bus *bus, unsigned int devfn, int cap);
548 int early_find_capability(struct pci_controller *hose, int bus, int devfn,
549 			  int cap)
550 {
551 	return pci_bus_find_capability(fake_pci_bus(hose, bus), devfn, cap);
552 }
553