2 * Taken from Linux v4.9 drivers/of/address.c
5 * Copyright (c) 2017 Google, Inc
7 * SPDX-License-Identifier: GPL-2.0+
12 #include <dm/of_access.h>
13 #include <dm/of_addr.h>
14 #include <linux/err.h>
15 #include <linux/ioport.h>
17 /* Max address size we deal with */
18 #define OF_MAX_ADDR_CELLS 4
19 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
20 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
22 static struct of_bus
*of_match_bus(struct device_node
*np
);
26 static void of_dump_addr(const char *s
, const __be32
*addr
, int na
)
30 pr_cont(" %08x", be32_to_cpu(*(addr
++)));
34 static void of_dump_addr(const char *s
, const __be32
*addr
, int na
) { }
37 /* Callbacks for bus specific translators */
40 const char *addresses
;
41 int (*match
)(struct device_node
*parent
);
42 void (*count_cells
)(const struct device_node
*child
, int *addrc
,
44 u64 (*map
)(__be32
*addr
, const __be32
*range
, int na
, int ns
, int pna
);
45 int (*translate
)(__be32
*addr
, u64 offset
, int na
);
46 unsigned int (*get_flags
)(const __be32
*addr
);
49 static void of_bus_default_count_cells(const struct device_node
*np
,
50 int *addrc
, int *sizec
)
53 *addrc
= of_n_addr_cells(np
);
55 *sizec
= of_n_size_cells(np
);
58 static u64
of_bus_default_map(__be32
*addr
, const __be32
*range
,
59 int na
, int ns
, int pna
)
63 cp
= of_read_number(range
, na
);
64 s
= of_read_number(range
+ na
+ pna
, ns
);
65 da
= of_read_number(addr
, na
);
67 debug("default map, cp=%llx, s=%llx, da=%llx\n",
68 (unsigned long long)cp
, (unsigned long long)s
,
69 (unsigned long long)da
);
71 if (da
< cp
|| da
>= (cp
+ s
))
76 static int of_bus_default_translate(__be32
*addr
, u64 offset
, int na
)
78 u64 a
= of_read_number(addr
, na
);
79 memset(addr
, 0, na
* 4);
82 addr
[na
- 2] = cpu_to_be32(a
>> 32);
83 addr
[na
- 1] = cpu_to_be32(a
& 0xffffffffu
);
88 static unsigned int of_bus_default_get_flags(const __be32
*addr
)
90 return IORESOURCE_MEM
;
94 * Array of bus-specific translators
96 static struct of_bus of_busses
[] = {
102 .count_cells
= of_bus_default_count_cells
,
103 .map
= of_bus_default_map
,
104 .translate
= of_bus_default_translate
,
105 .get_flags
= of_bus_default_get_flags
,
109 static struct of_bus
*of_match_bus(struct device_node
*np
)
113 for (i
= 0; i
< ARRAY_SIZE(of_busses
); i
++)
114 if (!of_busses
[i
].match
|| of_busses
[i
].match(np
))
115 return &of_busses
[i
];
120 static void dev_count_cells(const struct device_node
*np
, int *nap
, int *nsp
)
122 of_bus_default_count_cells(np
, nap
, nsp
);
125 const __be32
*of_get_address(const struct device_node
*dev
, int index
,
126 u64
*size
, unsigned int *flags
)
130 struct device_node
*parent
;
132 int onesize
, i
, na
, ns
;
134 /* Get parent & match bus type */
135 parent
= of_get_parent(dev
);
138 dev_count_cells(dev
, &na
, &ns
);
139 bus
= of_match_bus(parent
);
140 bus
->count_cells(dev
, &na
, &ns
);
142 if (!OF_CHECK_ADDR_COUNT(na
))
145 /* Get "reg" or "assigned-addresses" property */
146 prop
= of_get_property(dev
, "reg", &psize
);
152 for (i
= 0; psize
>= onesize
; psize
-= onesize
, prop
+= onesize
, i
++)
155 *size
= of_read_number(prop
+ na
, ns
);
157 *flags
= bus
->get_flags(prop
);
162 EXPORT_SYMBOL(of_get_address
);
164 static int of_empty_ranges_quirk(const struct device_node
*np
)
169 static int of_translate_one(const struct device_node
*parent
,
170 struct of_bus
*bus
, struct of_bus
*pbus
,
171 __be32
*addr
, int na
, int ns
, int pna
,
174 const __be32
*ranges
;
177 u64 offset
= OF_BAD_ADDR
;
180 * Normally, an absence of a "ranges" property means we are
181 * crossing a non-translatable boundary, and thus the addresses
182 * below the current cannot be converted to CPU physical ones.
183 * Unfortunately, while this is very clear in the spec, it's not
184 * what Apple understood, and they do have things like /uni-n or
185 * /ht nodes with no "ranges" property and a lot of perfectly
186 * useable mapped devices below them. Thus we treat the absence of
187 * "ranges" as equivalent to an empty "ranges" property which means
188 * a 1:1 translation at that level. It's up to the caller not to try
189 * to translate addresses that aren't supposed to be translated in
190 * the first place. --BenH.
192 * As far as we know, this damage only exists on Apple machines, so
193 * This code is only enabled on powerpc. --gcl
195 ranges
= of_get_property(parent
, rprop
, &rlen
);
196 if (ranges
== NULL
&& !of_empty_ranges_quirk(parent
)) {
197 debug("no ranges; cannot translate\n");
200 if (ranges
== NULL
|| rlen
== 0) {
201 offset
= of_read_number(addr
, na
);
202 memset(addr
, 0, pna
* 4);
203 debug("empty ranges; 1:1 translation\n");
207 debug("walking ranges...\n");
209 /* Now walk through the ranges */
211 rone
= na
+ pna
+ ns
;
212 for (; rlen
>= rone
; rlen
-= rone
, ranges
+= rone
) {
213 offset
= bus
->map(addr
, ranges
, na
, ns
, pna
);
214 if (offset
!= OF_BAD_ADDR
)
217 if (offset
== OF_BAD_ADDR
) {
218 debug("not found !\n");
221 memcpy(addr
, ranges
+ na
, 4 * pna
);
224 of_dump_addr("parent translation for:", addr
, pna
);
225 debug("with offset: %llx\n", (unsigned long long)offset
);
227 /* Translate it into parent bus space */
228 return pbus
->translate(addr
, offset
, pna
);
232 * Translate an address from the device-tree into a CPU physical address,
233 * this walks up the tree and applies the various bus mappings on the
236 * Note: We consider that crossing any level with #size-cells == 0 to mean
237 * that translation is impossible (that is we are not dealing with a value
238 * that can be mapped to a cpu physical address). This is not really specified
239 * that way, but this is traditionally the way IBM at least do things
241 static u64
__of_translate_address(const struct device_node
*dev
,
242 const __be32
*in_addr
, const char *rprop
)
244 struct device_node
*parent
= NULL
;
245 struct of_bus
*bus
, *pbus
;
246 __be32 addr
[OF_MAX_ADDR_CELLS
];
247 int na
, ns
, pna
, pns
;
248 u64 result
= OF_BAD_ADDR
;
250 debug("** translation for device %s **\n", of_node_full_name(dev
));
252 /* Increase refcount at current level */
253 (void)of_node_get(dev
);
255 /* Get parent & match bus type */
256 parent
= of_get_parent(dev
);
259 bus
= of_match_bus(parent
);
261 /* Count address cells & copy address locally */
262 bus
->count_cells(dev
, &na
, &ns
);
263 if (!OF_CHECK_COUNTS(na
, ns
)) {
264 debug("Bad cell count for %s\n", of_node_full_name(dev
));
267 memcpy(addr
, in_addr
, na
* 4);
269 debug("bus is %s (na=%d, ns=%d) on %s\n", bus
->name
, na
, ns
,
270 of_node_full_name(parent
));
271 of_dump_addr("translating address:", addr
, na
);
275 /* Switch to parent bus */
278 parent
= of_get_parent(dev
);
280 /* If root, we have finished */
281 if (parent
== NULL
) {
282 debug("reached root node\n");
283 result
= of_read_number(addr
, na
);
287 /* Get new parent bus and counts */
288 pbus
= of_match_bus(parent
);
289 pbus
->count_cells(dev
, &pna
, &pns
);
290 if (!OF_CHECK_COUNTS(pna
, pns
)) {
291 debug("Bad cell count for %s\n",
292 of_node_full_name(dev
));
296 debug("parent bus is %s (na=%d, ns=%d) on %s\n", pbus
->name
,
297 pna
, pns
, of_node_full_name(parent
));
299 /* Apply bus translation */
300 if (of_translate_one(dev
, bus
, pbus
, addr
, na
, ns
, pna
, rprop
))
303 /* Complete the move up one level */
308 of_dump_addr("one level translation:", addr
, na
);
317 u64
of_translate_address(const struct device_node
*dev
, const __be32
*in_addr
)
319 return __of_translate_address(dev
, in_addr
, "ranges");
323 static int __of_address_to_resource(const struct device_node
*dev
,
324 const __be32
*addrp
, u64 size
, unsigned int flags
,
325 const char *name
, struct resource
*r
)
329 if ((flags
& (IORESOURCE_IO
| IORESOURCE_MEM
)) == 0)
331 taddr
= of_translate_address(dev
, addrp
);
332 if (taddr
== OF_BAD_ADDR
)
334 memset(r
, 0, sizeof(struct resource
));
336 r
->end
= taddr
+ size
- 1;
338 r
->name
= name
? name
: dev
->full_name
;
343 int of_address_to_resource(const struct device_node
*dev
, int index
,
349 const char *name
= NULL
;
351 addrp
= of_get_address(dev
, index
, &size
, &flags
);
355 /* Get optional "reg-names" property to add a name to a resource */
356 of_property_read_string_index(dev
, "reg-names", index
, &name
);
358 return __of_address_to_resource(dev
, addrp
, size
, flags
, name
, r
);