xref: /linux/arch/powerpc/kernel/prom_parse.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
1 #undef DEBUG
2 
3 #include <linux/kernel.h>
4 #include <linux/string.h>
5 #include <linux/pci_regs.h>
6 #include <linux/module.h>
7 #include <linux/ioport.h>
8 #include <asm/prom.h>
9 #include <asm/pci-bridge.h>
10 
11 #ifdef DEBUG
12 #define DBG(fmt...) do { printk(fmt); } while(0)
13 #else
14 #define DBG(fmt...) do { } while(0)
15 #endif
16 
17 #ifdef CONFIG_PPC64
18 #define PRu64	"%lx"
19 #else
20 #define PRu64	"%llx"
21 #endif
22 
23 /* Max address size we deal with */
24 #define OF_MAX_ADDR_CELLS	4
25 #define OF_CHECK_COUNTS(na, ns)	((na) > 0 && (na) <= OF_MAX_ADDR_CELLS && \
26 			(ns) > 0)
27 
28 /* Debug utility */
29 #ifdef DEBUG
30 static void of_dump_addr(const char *s, u32 *addr, int na)
31 {
32 	printk("%s", s);
33 	while(na--)
34 		printk(" %08x", *(addr++));
35 	printk("\n");
36 }
37 #else
38 static void of_dump_addr(const char *s, u32 *addr, int na) { }
39 #endif
40 
41 /* Read a big address */
42 static inline u64 of_read_addr(u32 *cell, int size)
43 {
44 	u64 r = 0;
45 	while (size--)
46 		r = (r << 32) | *(cell++);
47 	return r;
48 }
49 
50 /* Callbacks for bus specific translators */
51 struct of_bus {
52 	const char	*name;
53 	const char	*addresses;
54 	int		(*match)(struct device_node *parent);
55 	void		(*count_cells)(struct device_node *child,
56 				       int *addrc, int *sizec);
57 	u64		(*map)(u32 *addr, u32 *range, int na, int ns, int pna);
58 	int		(*translate)(u32 *addr, u64 offset, int na);
59 	unsigned int	(*get_flags)(u32 *addr);
60 };
61 
62 
63 /*
64  * Default translator (generic bus)
65  */
66 
67 static void of_bus_default_count_cells(struct device_node *dev,
68 				       int *addrc, int *sizec)
69 {
70 	if (addrc)
71 		*addrc = prom_n_addr_cells(dev);
72 	if (sizec)
73 		*sizec = prom_n_size_cells(dev);
74 }
75 
76 static u64 of_bus_default_map(u32 *addr, u32 *range, int na, int ns, int pna)
77 {
78 	u64 cp, s, da;
79 
80 	cp = of_read_addr(range, na);
81 	s  = of_read_addr(range + na + pna, ns);
82 	da = of_read_addr(addr, na);
83 
84 	DBG("OF: default map, cp="PRu64", s="PRu64", da="PRu64"\n",
85 	    cp, s, da);
86 
87 	if (da < cp || da >= (cp + s))
88 		return OF_BAD_ADDR;
89 	return da - cp;
90 }
91 
92 static int of_bus_default_translate(u32 *addr, u64 offset, int na)
93 {
94 	u64 a = of_read_addr(addr, na);
95 	memset(addr, 0, na * 4);
96 	a += offset;
97 	if (na > 1)
98 		addr[na - 2] = a >> 32;
99 	addr[na - 1] = a & 0xffffffffu;
100 
101 	return 0;
102 }
103 
104 static unsigned int of_bus_default_get_flags(u32 *addr)
105 {
106 	return IORESOURCE_MEM;
107 }
108 
109 
110 /*
111  * PCI bus specific translator
112  */
113 
114 static int of_bus_pci_match(struct device_node *np)
115 {
116 	/* "vci" is for the /chaos bridge on 1st-gen PCI powermacs */
117 	return !strcmp(np->type, "pci") || !strcmp(np->type, "vci");
118 }
119 
120 static void of_bus_pci_count_cells(struct device_node *np,
121 				   int *addrc, int *sizec)
122 {
123 	if (addrc)
124 		*addrc = 3;
125 	if (sizec)
126 		*sizec = 2;
127 }
128 
129 static u64 of_bus_pci_map(u32 *addr, u32 *range, int na, int ns, int pna)
130 {
131 	u64 cp, s, da;
132 
133 	/* Check address type match */
134 	if ((addr[0] ^ range[0]) & 0x03000000)
135 		return OF_BAD_ADDR;
136 
137 	/* Read address values, skipping high cell */
138 	cp = of_read_addr(range + 1, na - 1);
139 	s  = of_read_addr(range + na + pna, ns);
140 	da = of_read_addr(addr + 1, na - 1);
141 
142 	DBG("OF: PCI map, cp="PRu64", s="PRu64", da="PRu64"\n", cp, s, da);
143 
144 	if (da < cp || da >= (cp + s))
145 		return OF_BAD_ADDR;
146 	return da - cp;
147 }
148 
149 static int of_bus_pci_translate(u32 *addr, u64 offset, int na)
150 {
151 	return of_bus_default_translate(addr + 1, offset, na - 1);
152 }
153 
154 static unsigned int of_bus_pci_get_flags(u32 *addr)
155 {
156 	unsigned int flags = 0;
157 	u32 w = addr[0];
158 
159 	switch((w >> 24) & 0x03) {
160 	case 0x01:
161 		flags |= IORESOURCE_IO;
162 	case 0x02: /* 32 bits */
163 	case 0x03: /* 64 bits */
164 		flags |= IORESOURCE_MEM;
165 	}
166 	if (w & 0x40000000)
167 		flags |= IORESOURCE_PREFETCH;
168 	return flags;
169 }
170 
171 /*
172  * ISA bus specific translator
173  */
174 
175 static int of_bus_isa_match(struct device_node *np)
176 {
177 	return !strcmp(np->name, "isa");
178 }
179 
180 static void of_bus_isa_count_cells(struct device_node *child,
181 				   int *addrc, int *sizec)
182 {
183 	if (addrc)
184 		*addrc = 2;
185 	if (sizec)
186 		*sizec = 1;
187 }
188 
189 static u64 of_bus_isa_map(u32 *addr, u32 *range, int na, int ns, int pna)
190 {
191 	u64 cp, s, da;
192 
193 	/* Check address type match */
194 	if ((addr[0] ^ range[0]) & 0x00000001)
195 		return OF_BAD_ADDR;
196 
197 	/* Read address values, skipping high cell */
198 	cp = of_read_addr(range + 1, na - 1);
199 	s  = of_read_addr(range + na + pna, ns);
200 	da = of_read_addr(addr + 1, na - 1);
201 
202 	DBG("OF: ISA map, cp="PRu64", s="PRu64", da="PRu64"\n", cp, s, da);
203 
204 	if (da < cp || da >= (cp + s))
205 		return OF_BAD_ADDR;
206 	return da - cp;
207 }
208 
209 static int of_bus_isa_translate(u32 *addr, u64 offset, int na)
210 {
211 	return of_bus_default_translate(addr + 1, offset, na - 1);
212 }
213 
214 static unsigned int of_bus_isa_get_flags(u32 *addr)
215 {
216 	unsigned int flags = 0;
217 	u32 w = addr[0];
218 
219 	if (w & 1)
220 		flags |= IORESOURCE_IO;
221 	else
222 		flags |= IORESOURCE_MEM;
223 	return flags;
224 }
225 
226 
227 /*
228  * Array of bus specific translators
229  */
230 
231 static struct of_bus of_busses[] = {
232 	/* PCI */
233 	{
234 		.name = "pci",
235 		.addresses = "assigned-addresses",
236 		.match = of_bus_pci_match,
237 		.count_cells = of_bus_pci_count_cells,
238 		.map = of_bus_pci_map,
239 		.translate = of_bus_pci_translate,
240 		.get_flags = of_bus_pci_get_flags,
241 	},
242 	/* ISA */
243 	{
244 		.name = "isa",
245 		.addresses = "reg",
246 		.match = of_bus_isa_match,
247 		.count_cells = of_bus_isa_count_cells,
248 		.map = of_bus_isa_map,
249 		.translate = of_bus_isa_translate,
250 		.get_flags = of_bus_isa_get_flags,
251 	},
252 	/* Default */
253 	{
254 		.name = "default",
255 		.addresses = "reg",
256 		.match = NULL,
257 		.count_cells = of_bus_default_count_cells,
258 		.map = of_bus_default_map,
259 		.translate = of_bus_default_translate,
260 		.get_flags = of_bus_default_get_flags,
261 	},
262 };
263 
264 static struct of_bus *of_match_bus(struct device_node *np)
265 {
266 	int i;
267 
268 	for (i = 0; i < ARRAY_SIZE(of_busses); i ++)
269 		if (!of_busses[i].match || of_busses[i].match(np))
270 			return &of_busses[i];
271 	BUG();
272 	return NULL;
273 }
274 
275 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
276 			    struct of_bus *pbus, u32 *addr,
277 			    int na, int ns, int pna)
278 {
279 	u32 *ranges;
280 	unsigned int rlen;
281 	int rone;
282 	u64 offset = OF_BAD_ADDR;
283 
284 	/* Normally, an absence of a "ranges" property means we are
285 	 * crossing a non-translatable boundary, and thus the addresses
286 	 * below the current not cannot be converted to CPU physical ones.
287 	 * Unfortunately, while this is very clear in the spec, it's not
288 	 * what Apple understood, and they do have things like /uni-n or
289 	 * /ht nodes with no "ranges" property and a lot of perfectly
290 	 * useable mapped devices below them. Thus we treat the absence of
291 	 * "ranges" as equivalent to an empty "ranges" property which means
292 	 * a 1:1 translation at that level. It's up to the caller not to try
293 	 * to translate addresses that aren't supposed to be translated in
294 	 * the first place. --BenH.
295 	 */
296 	ranges = (u32 *)get_property(parent, "ranges", &rlen);
297 	if (ranges == NULL || rlen == 0) {
298 		offset = of_read_addr(addr, na);
299 		memset(addr, 0, pna * 4);
300 		DBG("OF: no ranges, 1:1 translation\n");
301 		goto finish;
302 	}
303 
304 	DBG("OF: walking ranges...\n");
305 
306 	/* Now walk through the ranges */
307 	rlen /= 4;
308 	rone = na + pna + ns;
309 	for (; rlen >= rone; rlen -= rone, ranges += rone) {
310 		offset = bus->map(addr, ranges, na, ns, pna);
311 		if (offset != OF_BAD_ADDR)
312 			break;
313 	}
314 	if (offset == OF_BAD_ADDR) {
315 		DBG("OF: not found !\n");
316 		return 1;
317 	}
318 	memcpy(addr, ranges + na, 4 * pna);
319 
320  finish:
321 	of_dump_addr("OF: parent translation for:", addr, pna);
322 	DBG("OF: with offset: "PRu64"\n", offset);
323 
324 	/* Translate it into parent bus space */
325 	return pbus->translate(addr, offset, pna);
326 }
327 
328 
329 /*
330  * Translate an address from the device-tree into a CPU physical address,
331  * this walks up the tree and applies the various bus mappings on the
332  * way.
333  *
334  * Note: We consider that crossing any level with #size-cells == 0 to mean
335  * that translation is impossible (that is we are not dealing with a value
336  * that can be mapped to a cpu physical address). This is not really specified
337  * that way, but this is traditionally the way IBM at least do things
338  */
339 u64 of_translate_address(struct device_node *dev, u32 *in_addr)
340 {
341 	struct device_node *parent = NULL;
342 	struct of_bus *bus, *pbus;
343 	u32 addr[OF_MAX_ADDR_CELLS];
344 	int na, ns, pna, pns;
345 	u64 result = OF_BAD_ADDR;
346 
347 	DBG("OF: ** translation for device %s **\n", dev->full_name);
348 
349 	/* Increase refcount at current level */
350 	of_node_get(dev);
351 
352 	/* Get parent & match bus type */
353 	parent = of_get_parent(dev);
354 	if (parent == NULL)
355 		goto bail;
356 	bus = of_match_bus(parent);
357 
358 	/* Cound address cells & copy address locally */
359 	bus->count_cells(dev, &na, &ns);
360 	if (!OF_CHECK_COUNTS(na, ns)) {
361 		printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
362 		       dev->full_name);
363 		goto bail;
364 	}
365 	memcpy(addr, in_addr, na * 4);
366 
367 	DBG("OF: bus is %s (na=%d, ns=%d) on %s\n",
368 	    bus->name, na, ns, parent->full_name);
369 	of_dump_addr("OF: translating address:", addr, na);
370 
371 	/* Translate */
372 	for (;;) {
373 		/* Switch to parent bus */
374 		of_node_put(dev);
375 		dev = parent;
376 		parent = of_get_parent(dev);
377 
378 		/* If root, we have finished */
379 		if (parent == NULL) {
380 			DBG("OF: reached root node\n");
381 			result = of_read_addr(addr, na);
382 			break;
383 		}
384 
385 		/* Get new parent bus and counts */
386 		pbus = of_match_bus(parent);
387 		pbus->count_cells(dev, &pna, &pns);
388 		if (!OF_CHECK_COUNTS(pna, pns)) {
389 			printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
390 			       dev->full_name);
391 			break;
392 		}
393 
394 		DBG("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
395 		    pbus->name, pna, pns, parent->full_name);
396 
397 		/* Apply bus translation */
398 		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna))
399 			break;
400 
401 		/* Complete the move up one level */
402 		na = pna;
403 		ns = pns;
404 		bus = pbus;
405 
406 		of_dump_addr("OF: one level translation:", addr, na);
407 	}
408  bail:
409 	of_node_put(parent);
410 	of_node_put(dev);
411 
412 	return result;
413 }
414 EXPORT_SYMBOL(of_translate_address);
415 
416 u32 *of_get_address(struct device_node *dev, int index, u64 *size,
417 		    unsigned int *flags)
418 {
419 	u32 *prop;
420 	unsigned int psize;
421 	struct device_node *parent;
422 	struct of_bus *bus;
423 	int onesize, i, na, ns;
424 
425 	/* Get parent & match bus type */
426 	parent = of_get_parent(dev);
427 	if (parent == NULL)
428 		return NULL;
429 	bus = of_match_bus(parent);
430 	bus->count_cells(dev, &na, &ns);
431 	of_node_put(parent);
432 	if (!OF_CHECK_COUNTS(na, ns))
433 		return NULL;
434 
435 	/* Get "reg" or "assigned-addresses" property */
436 	prop = (u32 *)get_property(dev, bus->addresses, &psize);
437 	if (prop == NULL)
438 		return NULL;
439 	psize /= 4;
440 
441 	onesize = na + ns;
442 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
443 		if (i == index) {
444 			if (size)
445 				*size = of_read_addr(prop + na, ns);
446 			if (flags)
447 				*flags = bus->get_flags(prop);
448 			return prop;
449 		}
450 	return NULL;
451 }
452 EXPORT_SYMBOL(of_get_address);
453 
454 u32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
455 			unsigned int *flags)
456 {
457 	u32 *prop;
458 	unsigned int psize;
459 	struct device_node *parent;
460 	struct of_bus *bus;
461 	int onesize, i, na, ns;
462 
463 	/* Get parent & match bus type */
464 	parent = of_get_parent(dev);
465 	if (parent == NULL)
466 		return NULL;
467 	bus = of_match_bus(parent);
468 	if (strcmp(bus->name, "pci")) {
469 		of_node_put(parent);
470 		return NULL;
471 	}
472 	bus->count_cells(dev, &na, &ns);
473 	of_node_put(parent);
474 	if (!OF_CHECK_COUNTS(na, ns))
475 		return NULL;
476 
477 	/* Get "reg" or "assigned-addresses" property */
478 	prop = (u32 *)get_property(dev, bus->addresses, &psize);
479 	if (prop == NULL)
480 		return NULL;
481 	psize /= 4;
482 
483 	onesize = na + ns;
484 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
485 		if ((prop[0] & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
486 			if (size)
487 				*size = of_read_addr(prop + na, ns);
488 			if (flags)
489 				*flags = bus->get_flags(prop);
490 			return prop;
491 		}
492 	return NULL;
493 }
494 EXPORT_SYMBOL(of_get_pci_address);
495 
496 static int __of_address_to_resource(struct device_node *dev, u32 *addrp,
497 				    u64 size, unsigned int flags,
498 				    struct resource *r)
499 {
500 	u64 taddr;
501 
502 	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
503 		return -EINVAL;
504 	taddr = of_translate_address(dev, addrp);
505 	if (taddr == OF_BAD_ADDR)
506 		return -EINVAL;
507 	memset(r, 0, sizeof(struct resource));
508 	if (flags & IORESOURCE_IO) {
509 		unsigned long port;
510 		port = pci_address_to_pio(taddr);
511 		if (port == (unsigned long)-1)
512 			return -EINVAL;
513 		r->start = port;
514 		r->end = port + size - 1;
515 	} else {
516 		r->start = taddr;
517 		r->end = taddr + size - 1;
518 	}
519 	r->flags = flags;
520 	r->name = dev->name;
521 	return 0;
522 }
523 
524 int of_address_to_resource(struct device_node *dev, int index,
525 			   struct resource *r)
526 {
527 	u32		*addrp;
528 	u64		size;
529 	unsigned int	flags;
530 
531 	addrp = of_get_address(dev, index, &size, &flags);
532 	if (addrp == NULL)
533 		return -EINVAL;
534 	return __of_address_to_resource(dev, addrp, size, flags, r);
535 }
536 EXPORT_SYMBOL_GPL(of_address_to_resource);
537 
538 int of_pci_address_to_resource(struct device_node *dev, int bar,
539 			       struct resource *r)
540 {
541 	u32		*addrp;
542 	u64		size;
543 	unsigned int	flags;
544 
545 	addrp = of_get_pci_address(dev, bar, &size, &flags);
546 	if (addrp == NULL)
547 		return -EINVAL;
548 	return __of_address_to_resource(dev, addrp, size, flags, r);
549 }
550 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
551