1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Taken from Linux v4.9 drivers/of/address.c
4 *
5 * Modified for U-Boot
6 * Copyright (c) 2017 Google, Inc
7 */
8
9 #include <common.h>
10 #include <linux/libfdt.h>
11 #include <dm/of_access.h>
12 #include <dm/of_addr.h>
13 #include <linux/err.h>
14 #include <linux/ioport.h>
15
16 /* Max address size we deal with */
17 #define OF_MAX_ADDR_CELLS 4
18 #define OF_CHECK_ADDR_COUNT(na) ((na) > 0 && (na) <= OF_MAX_ADDR_CELLS)
19 #define OF_CHECK_COUNTS(na, ns) (OF_CHECK_ADDR_COUNT(na) && (ns) > 0)
20
21 static struct of_bus *of_match_bus(struct device_node *np);
22
23 /* Debug utility */
24 #ifdef DEBUG
of_dump_addr(const char * s,const __be32 * addr,int na)25 static void of_dump_addr(const char *s, const __be32 *addr, int na)
26 {
27 debug("%s", s);
28 while (na--)
29 pr_cont(" %08x", be32_to_cpu(*(addr++)));
30 pr_cont("\n");
31 }
32 #else
of_dump_addr(const char * s,const __be32 * addr,int na)33 static void of_dump_addr(const char *s, const __be32 *addr, int na) { }
34 #endif
35
36 /* Callbacks for bus specific translators */
37 struct of_bus {
38 const char *name;
39 const char *addresses;
40 int (*match)(struct device_node *parent);
41 void (*count_cells)(const struct device_node *child, int *addrc,
42 int *sizec);
43 u64 (*map)(__be32 *addr, const __be32 *range, int na, int ns, int pna);
44 int (*translate)(__be32 *addr, u64 offset, int na);
45 unsigned int (*get_flags)(const __be32 *addr);
46 };
47
of_bus_default_count_cells(const struct device_node * np,int * addrc,int * sizec)48 static void of_bus_default_count_cells(const struct device_node *np,
49 int *addrc, int *sizec)
50 {
51 if (addrc)
52 *addrc = of_n_addr_cells(np);
53 if (sizec)
54 *sizec = of_n_size_cells(np);
55 }
56
of_bus_default_map(__be32 * addr,const __be32 * range,int na,int ns,int pna)57 static u64 of_bus_default_map(__be32 *addr, const __be32 *range,
58 int na, int ns, int pna)
59 {
60 u64 cp, s, da;
61
62 cp = of_read_number(range, na);
63 s = of_read_number(range + na + pna, ns);
64 da = of_read_number(addr, na);
65
66 debug("default map, cp=%llx, s=%llx, da=%llx\n",
67 (unsigned long long)cp, (unsigned long long)s,
68 (unsigned long long)da);
69
70 if (da < cp || da >= (cp + s))
71 return OF_BAD_ADDR;
72 return da - cp;
73 }
74
of_bus_default_translate(__be32 * addr,u64 offset,int na)75 static int of_bus_default_translate(__be32 *addr, u64 offset, int na)
76 {
77 u64 a = of_read_number(addr, na);
78 memset(addr, 0, na * 4);
79 a += offset;
80 if (na > 1)
81 addr[na - 2] = cpu_to_be32(a >> 32);
82 addr[na - 1] = cpu_to_be32(a & 0xffffffffu);
83
84 return 0;
85 }
86
of_bus_default_get_flags(const __be32 * addr)87 static unsigned int of_bus_default_get_flags(const __be32 *addr)
88 {
89 return IORESOURCE_MEM;
90 }
91
92 /*
93 * Array of bus-specific translators
94 */
95 static struct of_bus of_busses[] = {
96 /* Default */
97 {
98 .name = "default",
99 .addresses = "reg",
100 .match = NULL,
101 .count_cells = of_bus_default_count_cells,
102 .map = of_bus_default_map,
103 .translate = of_bus_default_translate,
104 .get_flags = of_bus_default_get_flags,
105 },
106 };
107
of_match_bus(struct device_node * np)108 static struct of_bus *of_match_bus(struct device_node *np)
109 {
110 int i;
111
112 for (i = 0; i < ARRAY_SIZE(of_busses); i++)
113 if (!of_busses[i].match || of_busses[i].match(np))
114 return &of_busses[i];
115 BUG();
116 return NULL;
117 }
118
dev_count_cells(const struct device_node * np,int * nap,int * nsp)119 static void dev_count_cells(const struct device_node *np, int *nap, int *nsp)
120 {
121 of_bus_default_count_cells(np, nap, nsp);
122 }
123
of_get_address(const struct device_node * dev,int index,u64 * size,unsigned int * flags)124 const __be32 *of_get_address(const struct device_node *dev, int index,
125 u64 *size, unsigned int *flags)
126 {
127 const __be32 *prop;
128 int psize;
129 struct device_node *parent;
130 struct of_bus *bus;
131 int onesize, i, na, ns;
132
133 /* Get parent & match bus type */
134 parent = of_get_parent(dev);
135 if (parent == NULL)
136 return NULL;
137 dev_count_cells(dev, &na, &ns);
138 bus = of_match_bus(parent);
139 bus->count_cells(dev, &na, &ns);
140 of_node_put(parent);
141 if (!OF_CHECK_ADDR_COUNT(na))
142 return NULL;
143
144 /* Get "reg" or "assigned-addresses" property */
145 prop = of_get_property(dev, "reg", &psize);
146 if (prop == NULL)
147 return NULL;
148 psize /= 4;
149
150 onesize = na + ns;
151 for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++)
152 if (i == index) {
153 if (size)
154 *size = of_read_number(prop + na, ns);
155 if (flags)
156 *flags = bus->get_flags(prop);
157 return prop;
158 }
159 return NULL;
160 }
161 EXPORT_SYMBOL(of_get_address);
162
of_empty_ranges_quirk(const struct device_node * np)163 static int of_empty_ranges_quirk(const struct device_node *np)
164 {
165 return false;
166 }
167
of_translate_one(const struct device_node * parent,struct of_bus * bus,struct of_bus * pbus,__be32 * addr,int na,int ns,int pna,const char * rprop)168 static int of_translate_one(const struct device_node *parent,
169 struct of_bus *bus, struct of_bus *pbus,
170 __be32 *addr, int na, int ns, int pna,
171 const char *rprop)
172 {
173 const __be32 *ranges;
174 int rlen;
175 int rone;
176 u64 offset = OF_BAD_ADDR;
177
178 /*
179 * Normally, an absence of a "ranges" property means we are
180 * crossing a non-translatable boundary, and thus the addresses
181 * below the current cannot be converted to CPU physical ones.
182 * Unfortunately, while this is very clear in the spec, it's not
183 * what Apple understood, and they do have things like /uni-n or
184 * /ht nodes with no "ranges" property and a lot of perfectly
185 * useable mapped devices below them. Thus we treat the absence of
186 * "ranges" as equivalent to an empty "ranges" property which means
187 * a 1:1 translation at that level. It's up to the caller not to try
188 * to translate addresses that aren't supposed to be translated in
189 * the first place. --BenH.
190 *
191 * As far as we know, this damage only exists on Apple machines, so
192 * This code is only enabled on powerpc. --gcl
193 */
194 ranges = of_get_property(parent, rprop, &rlen);
195 if (ranges == NULL && !of_empty_ranges_quirk(parent)) {
196 debug("no ranges; cannot translate\n");
197 return 1;
198 }
199 if (ranges == NULL || rlen == 0) {
200 offset = of_read_number(addr, na);
201 memset(addr, 0, pna * 4);
202 debug("empty ranges; 1:1 translation\n");
203 goto finish;
204 }
205
206 debug("walking ranges...\n");
207
208 /* Now walk through the ranges */
209 rlen /= 4;
210 rone = na + pna + ns;
211 for (; rlen >= rone; rlen -= rone, ranges += rone) {
212 offset = bus->map(addr, ranges, na, ns, pna);
213 if (offset != OF_BAD_ADDR)
214 break;
215 }
216 if (offset == OF_BAD_ADDR) {
217 debug("not found !\n");
218 return 1;
219 }
220 memcpy(addr, ranges + na, 4 * pna);
221
222 finish:
223 of_dump_addr("parent translation for:", addr, pna);
224 debug("with offset: %llx\n", (unsigned long long)offset);
225
226 /* Translate it into parent bus space */
227 return pbus->translate(addr, offset, pna);
228 }
229
230 /*
231 * Translate an address from the device-tree into a CPU physical address,
232 * this walks up the tree and applies the various bus mappings on the
233 * way.
234 *
235 * Note: We consider that crossing any level with #size-cells == 0 to mean
236 * that translation is impossible (that is we are not dealing with a value
237 * that can be mapped to a cpu physical address). This is not really specified
238 * that way, but this is traditionally the way IBM at least do things
239 */
__of_translate_address(const struct device_node * dev,const __be32 * in_addr,const char * rprop)240 static u64 __of_translate_address(const struct device_node *dev,
241 const __be32 *in_addr, const char *rprop)
242 {
243 struct device_node *parent = NULL;
244 struct of_bus *bus, *pbus;
245 __be32 addr[OF_MAX_ADDR_CELLS];
246 int na, ns, pna, pns;
247 u64 result = OF_BAD_ADDR;
248
249 debug("** translation for device %s **\n", of_node_full_name(dev));
250
251 /* Increase refcount at current level */
252 (void)of_node_get(dev);
253
254 /* Get parent & match bus type */
255 parent = of_get_parent(dev);
256 if (parent == NULL)
257 goto bail;
258 bus = of_match_bus(parent);
259
260 /* Count address cells & copy address locally */
261 bus->count_cells(dev, &na, &ns);
262 if (!OF_CHECK_COUNTS(na, ns)) {
263 debug("Bad cell count for %s\n", of_node_full_name(dev));
264 goto bail;
265 }
266 memcpy(addr, in_addr, na * 4);
267
268 debug("bus is %s (na=%d, ns=%d) on %s\n", bus->name, na, ns,
269 of_node_full_name(parent));
270 of_dump_addr("translating address:", addr, na);
271
272 /* Translate */
273 for (;;) {
274 /* Switch to parent bus */
275 of_node_put(dev);
276 dev = parent;
277 parent = of_get_parent(dev);
278
279 /* If root, we have finished */
280 if (parent == NULL) {
281 debug("reached root node\n");
282 result = of_read_number(addr, na);
283 break;
284 }
285
286 /* Get new parent bus and counts */
287 pbus = of_match_bus(parent);
288 pbus->count_cells(dev, &pna, &pns);
289 if (!OF_CHECK_COUNTS(pna, pns)) {
290 debug("Bad cell count for %s\n",
291 of_node_full_name(dev));
292 break;
293 }
294
295 debug("parent bus is %s (na=%d, ns=%d) on %s\n", pbus->name,
296 pna, pns, of_node_full_name(parent));
297
298 /* Apply bus translation */
299 if (of_translate_one(dev, bus, pbus, addr, na, ns, pna, rprop))
300 break;
301
302 /* Complete the move up one level */
303 na = pna;
304 ns = pns;
305 bus = pbus;
306
307 of_dump_addr("one level translation:", addr, na);
308 }
309 bail:
310 of_node_put(parent);
311 of_node_put(dev);
312
313 return result;
314 }
315
of_translate_address(const struct device_node * dev,const __be32 * in_addr)316 u64 of_translate_address(const struct device_node *dev, const __be32 *in_addr)
317 {
318 return __of_translate_address(dev, in_addr, "ranges");
319 }
320
321
__of_address_to_resource(const struct device_node * dev,const __be32 * addrp,u64 size,unsigned int flags,const char * name,struct resource * r)322 static int __of_address_to_resource(const struct device_node *dev,
323 const __be32 *addrp, u64 size, unsigned int flags,
324 const char *name, struct resource *r)
325 {
326 u64 taddr;
327
328 if ((flags & (IORESOURCE_IO | IORESOURCE_MEM)) == 0)
329 return -EINVAL;
330 taddr = of_translate_address(dev, addrp);
331 if (taddr == OF_BAD_ADDR)
332 return -EINVAL;
333 memset(r, 0, sizeof(struct resource));
334 r->start = taddr;
335 r->end = taddr + size - 1;
336 r->flags = flags;
337 r->name = name ? name : dev->full_name;
338
339 return 0;
340 }
341
of_address_to_resource(const struct device_node * dev,int index,struct resource * r)342 int of_address_to_resource(const struct device_node *dev, int index,
343 struct resource *r)
344 {
345 const __be32 *addrp;
346 u64 size;
347 unsigned int flags;
348 const char *name = NULL;
349
350 addrp = of_get_address(dev, index, &size, &flags);
351 if (addrp == NULL)
352 return -EINVAL;
353
354 /* Get optional "reg-names" property to add a name to a resource */
355 of_property_read_string_index(dev, "reg-names", index, &name);
356
357 return __of_address_to_resource(dev, addrp, size, flags, name, r);
358 }
359