xref: /openbmc/linux/arch/powerpc/kernel/prom_parse.c (revision 87c2ce3b)
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 	return !strcmp(np->type, "pci");
117 }
118 
119 static void of_bus_pci_count_cells(struct device_node *np,
120 				   int *addrc, int *sizec)
121 {
122 	if (addrc)
123 		*addrc = 3;
124 	if (sizec)
125 		*sizec = 2;
126 }
127 
128 static u64 of_bus_pci_map(u32 *addr, u32 *range, int na, int ns, int pna)
129 {
130 	u64 cp, s, da;
131 
132 	/* Check address type match */
133 	if ((addr[0] ^ range[0]) & 0x03000000)
134 		return OF_BAD_ADDR;
135 
136 	/* Read address values, skipping high cell */
137 	cp = of_read_addr(range + 1, na - 1);
138 	s  = of_read_addr(range + na + pna, ns);
139 	da = of_read_addr(addr + 1, na - 1);
140 
141 	DBG("OF: PCI map, cp="PRu64", s="PRu64", da="PRu64"\n", cp, s, da);
142 
143 	if (da < cp || da >= (cp + s))
144 		return OF_BAD_ADDR;
145 	return da - cp;
146 }
147 
148 static int of_bus_pci_translate(u32 *addr, u64 offset, int na)
149 {
150 	return of_bus_default_translate(addr + 1, offset, na - 1);
151 }
152 
153 static unsigned int of_bus_pci_get_flags(u32 *addr)
154 {
155 	unsigned int flags = 0;
156 	u32 w = addr[0];
157 
158 	switch((w >> 24) & 0x03) {
159 	case 0x01:
160 		flags |= IORESOURCE_IO;
161 	case 0x02: /* 32 bits */
162 	case 0x03: /* 64 bits */
163 		flags |= IORESOURCE_MEM;
164 	}
165 	if (w & 0x40000000)
166 		flags |= IORESOURCE_PREFETCH;
167 	return flags;
168 }
169 
170 /*
171  * ISA bus specific translator
172  */
173 
174 static int of_bus_isa_match(struct device_node *np)
175 {
176 	return !strcmp(np->name, "isa");
177 }
178 
179 static void of_bus_isa_count_cells(struct device_node *child,
180 				   int *addrc, int *sizec)
181 {
182 	if (addrc)
183 		*addrc = 2;
184 	if (sizec)
185 		*sizec = 1;
186 }
187 
188 static u64 of_bus_isa_map(u32 *addr, u32 *range, int na, int ns, int pna)
189 {
190 	u64 cp, s, da;
191 
192 	/* Check address type match */
193 	if ((addr[0] ^ range[0]) & 0x00000001)
194 		return OF_BAD_ADDR;
195 
196 	/* Read address values, skipping high cell */
197 	cp = of_read_addr(range + 1, na - 1);
198 	s  = of_read_addr(range + na + pna, ns);
199 	da = of_read_addr(addr + 1, na - 1);
200 
201 	DBG("OF: ISA map, cp="PRu64", s="PRu64", da="PRu64"\n", cp, s, da);
202 
203 	if (da < cp || da >= (cp + s))
204 		return OF_BAD_ADDR;
205 	return da - cp;
206 }
207 
208 static int of_bus_isa_translate(u32 *addr, u64 offset, int na)
209 {
210 	return of_bus_default_translate(addr + 1, offset, na - 1);
211 }
212 
213 static unsigned int of_bus_isa_get_flags(u32 *addr)
214 {
215 	unsigned int flags = 0;
216 	u32 w = addr[0];
217 
218 	if (w & 1)
219 		flags |= IORESOURCE_IO;
220 	else
221 		flags |= IORESOURCE_MEM;
222 	return flags;
223 }
224 
225 
226 /*
227  * Array of bus specific translators
228  */
229 
230 static struct of_bus of_busses[] = {
231 	/* PCI */
232 	{
233 		.name = "pci",
234 		.addresses = "assigned-addresses",
235 		.match = of_bus_pci_match,
236 		.count_cells = of_bus_pci_count_cells,
237 		.map = of_bus_pci_map,
238 		.translate = of_bus_pci_translate,
239 		.get_flags = of_bus_pci_get_flags,
240 	},
241 	/* ISA */
242 	{
243 		.name = "isa",
244 		.addresses = "reg",
245 		.match = of_bus_isa_match,
246 		.count_cells = of_bus_isa_count_cells,
247 		.map = of_bus_isa_map,
248 		.translate = of_bus_isa_translate,
249 		.get_flags = of_bus_isa_get_flags,
250 	},
251 	/* Default */
252 	{
253 		.name = "default",
254 		.addresses = "reg",
255 		.match = NULL,
256 		.count_cells = of_bus_default_count_cells,
257 		.map = of_bus_default_map,
258 		.translate = of_bus_default_translate,
259 		.get_flags = of_bus_default_get_flags,
260 	},
261 };
262 
263 static struct of_bus *of_match_bus(struct device_node *np)
264 {
265 	int i;
266 
267 	for (i = 0; i < ARRAY_SIZE(of_busses); i ++)
268 		if (!of_busses[i].match || of_busses[i].match(np))
269 			return &of_busses[i];
270 	BUG();
271 	return NULL;
272 }
273 
274 static int of_translate_one(struct device_node *parent, struct of_bus *bus,
275 			    struct of_bus *pbus, u32 *addr,
276 			    int na, int ns, int pna)
277 {
278 	u32 *ranges;
279 	unsigned int rlen;
280 	int rone;
281 	u64 offset = OF_BAD_ADDR;
282 
283 	/* Normally, an absence of a "ranges" property means we are
284 	 * crossing a non-translatable boundary, and thus the addresses
285 	 * below the current not cannot be converted to CPU physical ones.
286 	 * Unfortunately, while this is very clear in the spec, it's not
287 	 * what Apple understood, and they do have things like /uni-n or
288 	 * /ht nodes with no "ranges" property and a lot of perfectly
289 	 * useable mapped devices below them. Thus we treat the absence of
290 	 * "ranges" as equivalent to an empty "ranges" property which means
291 	 * a 1:1 translation at that level. It's up to the caller not to try
292 	 * to translate addresses that aren't supposed to be translated in
293 	 * the first place. --BenH.
294 	 */
295 	ranges = (u32 *)get_property(parent, "ranges", &rlen);
296 	if (ranges == NULL || rlen == 0) {
297 		offset = of_read_addr(addr, na);
298 		memset(addr, 0, pna * 4);
299 		DBG("OF: no ranges, 1:1 translation\n");
300 		goto finish;
301 	}
302 
303 	DBG("OF: walking ranges...\n");
304 
305 	/* Now walk through the ranges */
306 	rlen /= 4;
307 	rone = na + pna + ns;
308 	for (; rlen >= rone; rlen -= rone, ranges += rone) {
309 		offset = bus->map(addr, ranges, na, ns, pna);
310 		if (offset != OF_BAD_ADDR)
311 			break;
312 	}
313 	if (offset == OF_BAD_ADDR) {
314 		DBG("OF: not found !\n");
315 		return 1;
316 	}
317 	memcpy(addr, ranges + na, 4 * pna);
318 
319  finish:
320 	of_dump_addr("OF: parent translation for:", addr, pna);
321 	DBG("OF: with offset: "PRu64"\n", offset);
322 
323 	/* Translate it into parent bus space */
324 	return pbus->translate(addr, offset, pna);
325 }
326 
327 
328 /*
329  * Translate an address from the device-tree into a CPU physical address,
330  * this walks up the tree and applies the various bus mappings on the
331  * way.
332  *
333  * Note: We consider that crossing any level with #size-cells == 0 to mean
334  * that translation is impossible (that is we are not dealing with a value
335  * that can be mapped to a cpu physical address). This is not really specified
336  * that way, but this is traditionally the way IBM at least do things
337  */
338 u64 of_translate_address(struct device_node *dev, u32 *in_addr)
339 {
340 	struct device_node *parent = NULL;
341 	struct of_bus *bus, *pbus;
342 	u32 addr[OF_MAX_ADDR_CELLS];
343 	int na, ns, pna, pns;
344 	u64 result = OF_BAD_ADDR;
345 
346 	DBG("OF: ** translation for device %s **\n", dev->full_name);
347 
348 	/* Increase refcount at current level */
349 	of_node_get(dev);
350 
351 	/* Get parent & match bus type */
352 	parent = of_get_parent(dev);
353 	if (parent == NULL)
354 		goto bail;
355 	bus = of_match_bus(parent);
356 
357 	/* Cound address cells & copy address locally */
358 	bus->count_cells(dev, &na, &ns);
359 	if (!OF_CHECK_COUNTS(na, ns)) {
360 		printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
361 		       dev->full_name);
362 		goto bail;
363 	}
364 	memcpy(addr, in_addr, na * 4);
365 
366 	DBG("OF: bus is %s (na=%d, ns=%d) on %s\n",
367 	    bus->name, na, ns, parent->full_name);
368 	of_dump_addr("OF: translating address:", addr, na);
369 
370 	/* Translate */
371 	for (;;) {
372 		/* Switch to parent bus */
373 		of_node_put(dev);
374 		dev = parent;
375 		parent = of_get_parent(dev);
376 
377 		/* If root, we have finished */
378 		if (parent == NULL) {
379 			DBG("OF: reached root node\n");
380 			result = of_read_addr(addr, na);
381 			break;
382 		}
383 
384 		/* Get new parent bus and counts */
385 		pbus = of_match_bus(parent);
386 		pbus->count_cells(dev, &pna, &pns);
387 		if (!OF_CHECK_COUNTS(pna, pns)) {
388 			printk(KERN_ERR "prom_parse: Bad cell count for %s\n",
389 			       dev->full_name);
390 			break;
391 		}
392 
393 		DBG("OF: parent bus is %s (na=%d, ns=%d) on %s\n",
394 		    pbus->name, pna, pns, parent->full_name);
395 
396 		/* Apply bus translation */
397 		if (of_translate_one(dev, bus, pbus, addr, na, ns, pna))
398 			break;
399 
400 		/* Complete the move up one level */
401 		na = pna;
402 		ns = pns;
403 		bus = pbus;
404 
405 		of_dump_addr("OF: one level translation:", addr, na);
406 	}
407  bail:
408 	of_node_put(parent);
409 	of_node_put(dev);
410 
411 	return result;
412 }
413 EXPORT_SYMBOL(of_translate_address);
414 
415 u32 *of_get_address(struct device_node *dev, int index, u64 *size,
416 		    unsigned int *flags)
417 {
418 	u32 *prop;
419 	unsigned int psize;
420 	struct device_node *parent;
421 	struct of_bus *bus;
422 	int onesize, i, na, ns;
423 
424 	/* Get parent & match bus type */
425 	parent = of_get_parent(dev);
426 	if (parent == NULL)
427 		return NULL;
428 	bus = of_match_bus(parent);
429 	bus->count_cells(dev, &na, &ns);
430 	of_node_put(parent);
431 	if (!OF_CHECK_COUNTS(na, ns))
432 		return NULL;
433 
434 	/* Get "reg" or "assigned-addresses" property */
435 	prop = (u32 *)get_property(dev, bus->addresses, &psize);
436 	if (prop == NULL)
437 		return NULL;
438 	psize /= 4;
439 
440 	onesize = na + ns;
441 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
442 		if (i == index) {
443 			if (size)
444 				*size = of_read_addr(prop + na, ns);
445 			if (flags)
446 				*flags = bus->get_flags(prop);
447 			return prop;
448 		}
449 	return NULL;
450 }
451 EXPORT_SYMBOL(of_get_address);
452 
453 u32 *of_get_pci_address(struct device_node *dev, int bar_no, u64 *size,
454 			unsigned int *flags)
455 {
456 	u32 *prop;
457 	unsigned int psize;
458 	struct device_node *parent;
459 	struct of_bus *bus;
460 	int onesize, i, na, ns;
461 
462 	/* Get parent & match bus type */
463 	parent = of_get_parent(dev);
464 	if (parent == NULL)
465 		return NULL;
466 	bus = of_match_bus(parent);
467 	if (strcmp(bus->name, "pci"))
468 		return NULL;
469 	bus->count_cells(dev, &na, &ns);
470 	of_node_put(parent);
471 	if (!OF_CHECK_COUNTS(na, ns))
472 		return NULL;
473 
474 	/* Get "reg" or "assigned-addresses" property */
475 	prop = (u32 *)get_property(dev, bus->addresses, &psize);
476 	if (prop == NULL)
477 		return NULL;
478 	psize /= 4;
479 
480 	onesize = na + ns;
481 	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
482 		if ((prop[0] & 0xff) == ((bar_no * 4) + PCI_BASE_ADDRESS_0)) {
483 			if (size)
484 				*size = of_read_addr(prop + na, ns);
485 			if (flags)
486 				*flags = bus->get_flags(prop);
487 			return prop;
488 		}
489 	return NULL;
490 }
491 EXPORT_SYMBOL(of_get_pci_address);
492 
493 static int __of_address_to_resource(struct device_node *dev, u32 *addrp,
494 				    u64 size, unsigned int flags,
495 				    struct resource *r)
496 {
497 	u64 taddr;
498 
499 	if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
500 		return -EINVAL;
501 	taddr = of_translate_address(dev, addrp);
502 	if (taddr == OF_BAD_ADDR)
503 		return -EINVAL;
504 	memset(r, 0, sizeof(struct resource));
505 	if (flags & IORESOURCE_IO) {
506 		unsigned long port;
507 		port = pci_address_to_pio(taddr);
508 		if (port == (unsigned long)-1)
509 			return -EINVAL;
510 		r->start = port;
511 		r->end = port + size - 1;
512 	} else {
513 		r->start = taddr;
514 		r->end = taddr + size - 1;
515 	}
516 	r->flags = flags;
517 	r->name = dev->name;
518 	return 0;
519 }
520 
521 int of_address_to_resource(struct device_node *dev, int index,
522 			   struct resource *r)
523 {
524 	u32		*addrp;
525 	u64		size;
526 	unsigned int	flags;
527 
528 	addrp = of_get_address(dev, index, &size, &flags);
529 	if (addrp == NULL)
530 		return -EINVAL;
531 	return __of_address_to_resource(dev, addrp, size, flags, r);
532 }
533 EXPORT_SYMBOL_GPL(of_address_to_resource);
534 
535 int of_pci_address_to_resource(struct device_node *dev, int bar,
536 			       struct resource *r)
537 {
538 	u32		*addrp;
539 	u64		size;
540 	unsigned int	flags;
541 
542 	addrp = of_get_pci_address(dev, bar, &size, &flags);
543 	if (addrp == NULL)
544 		return -EINVAL;
545 	return __of_address_to_resource(dev, addrp, size, flags, r);
546 }
547 EXPORT_SYMBOL_GPL(of_pci_address_to_resource);
548