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devtree.c
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1 /*
2  * devtree.c - convenience functions for device tree manipulation
3  * Copyright 2007 David Gibson, IBM Corporation.
4  * Copyright (c) 2007 Freescale Semiconductor, Inc.
5  *
6  * Authors: David Gibson <[email protected]>
7  * Scott Wood <[email protected]>
8  *
9  * This program is free software; you can redistribute it and/or
10  * modify it under the terms of the GNU General Public License
11  * as published by the Free Software Foundation; either version
12  * 2 of the License, or (at your option) any later version.
13  */
14 #include <stdarg.h>
15 #include <stddef.h>
16 #include "types.h"
17 #include "string.h"
18 #include "stdio.h"
19 #include "ops.h"
20 
22 {
23  void *root, *memory;
24  int naddr, nsize, i;
25  u32 memreg[4];
26 
27  root = finddevice("/");
28  if (getprop(root, "#address-cells", &naddr, sizeof(naddr)) < 0)
29  naddr = 2;
30  if (naddr < 1 || naddr > 2)
31  fatal("Can't cope with #address-cells == %d in /\n\r", naddr);
32 
33  if (getprop(root, "#size-cells", &nsize, sizeof(nsize)) < 0)
34  nsize = 1;
35  if (nsize < 1 || nsize > 2)
36  fatal("Can't cope with #size-cells == %d in /\n\r", nsize);
37 
38  i = 0;
39  if (naddr == 2)
40  memreg[i++] = start >> 32;
41  memreg[i++] = start & 0xffffffff;
42  if (nsize == 2)
43  memreg[i++] = size >> 32;
44  memreg[i++] = size & 0xffffffff;
45 
46  memory = finddevice("/memory");
47  if (! memory) {
48  memory = create_node(NULL, "memory");
49  setprop_str(memory, "device_type", "memory");
50  }
51 
52  printf("Memory <- <0x%x", memreg[0]);
53  for (i = 1; i < (naddr + nsize); i++)
54  printf(" 0x%x", memreg[i]);
55  printf("> (%ldMB)\n\r", (unsigned long)(size >> 20));
56 
57  setprop(memory, "reg", memreg, (naddr + nsize)*sizeof(u32));
58 }
59 
60 #define MHZ(x) ((x + 500000) / 1000000)
61 
63 {
64  void *devp = NULL;
65 
66  printf("CPU clock-frequency <- 0x%x (%dMHz)\n\r", cpu, MHZ(cpu));
67  printf("CPU timebase-frequency <- 0x%x (%dMHz)\n\r", tb, MHZ(tb));
68  if (bus > 0)
69  printf("CPU bus-frequency <- 0x%x (%dMHz)\n\r", bus, MHZ(bus));
70 
71  while ((devp = find_node_by_devtype(devp, "cpu"))) {
72  setprop_val(devp, "clock-frequency", cpu);
73  setprop_val(devp, "timebase-frequency", tb);
74  if (bus > 0)
75  setprop_val(devp, "bus-frequency", bus);
76  }
77 
78  timebase_period_ns = 1000000000 / tb;
79 }
80 
81 void dt_fixup_clock(const char *path, u32 freq)
82 {
83  void *devp = finddevice(path);
84 
85  if (devp) {
86  printf("%s: clock-frequency <- %x (%dMHz)\n\r", path, freq, MHZ(freq));
87  setprop_val(devp, "clock-frequency", freq);
88  }
89 }
90 
91 void dt_fixup_mac_address_by_alias(const char *alias, const u8 *addr)
92 {
93  void *devp = find_node_by_alias(alias);
94 
95  if (devp) {
96  printf("%s: local-mac-address <-"
97  " %02x:%02x:%02x:%02x:%02x:%02x\n\r", alias,
98  addr[0], addr[1], addr[2],
99  addr[3], addr[4], addr[5]);
100 
101  setprop(devp, "local-mac-address", addr, 6);
102  }
103 }
104 
106 {
107  void *devp = find_node_by_prop_value(NULL, "linux,network-index",
108  (void*)&index, sizeof(index));
109 
110  if (devp) {
111  printf("ENET%d: local-mac-address <-"
112  " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
113  addr[0], addr[1], addr[2],
114  addr[3], addr[4], addr[5]);
115 
116  setprop(devp, "local-mac-address", addr, 6);
117  }
118 }
119 
120 void __dt_fixup_mac_addresses(u32 startindex, ...)
121 {
122  va_list ap;
123  u32 index = startindex;
124  const u8 *addr;
125 
126  va_start(ap, startindex);
127 
128  while ((addr = va_arg(ap, const u8 *)))
129  dt_fixup_mac_address(index++, addr);
130 
131  va_end(ap);
132 }
133 
134 #define MAX_ADDR_CELLS 4
135 
136 void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)
137 {
138  if (getprop(node, "#address-cells", naddr, 4) != 4)
139  *naddr = 2;
140  if (getprop(node, "#size-cells", nsize, 4) != 4)
141  *nsize = 1;
142 }
143 
144 static void copy_val(u32 *dest, u32 *src, int naddr)
145 {
146  int pad = MAX_ADDR_CELLS - naddr;
147 
148  memset(dest, 0, pad * 4);
149  memcpy(dest + pad, src, naddr * 4);
150 }
151 
152 static int sub_reg(u32 *reg, u32 *sub)
153 {
154  int i, borrow = 0;
155 
156  for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {
157  int prev_borrow = borrow;
158  borrow = reg[i] < sub[i] + prev_borrow;
159  reg[i] -= sub[i] + prev_borrow;
160  }
161 
162  return !borrow;
163 }
164 
165 static int add_reg(u32 *reg, u32 *add, int naddr)
166 {
167  int i, carry = 0;
168 
169  for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {
170  u64 tmp = (u64)reg[i] + add[i] + carry;
171  carry = tmp >> 32;
172  reg[i] = (u32)tmp;
173  }
174 
175  return !carry;
176 }
177 
178 /* It is assumed that if the first byte of reg fits in a
179  * range, then the whole reg block fits.
180  */
181 static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
182 {
183  int i;
184  u32 end;
185 
186  for (i = 0; i < MAX_ADDR_CELLS; i++) {
187  if (reg[i] < range[i])
188  return 0;
189  if (reg[i] > range[i])
190  break;
191  }
192 
193  for (i = 0; i < MAX_ADDR_CELLS; i++) {
194  end = range[i] + rangesize[i];
195 
196  if (reg[i] < end)
197  break;
198  if (reg[i] > end)
199  return 0;
200  }
201 
202  return reg[i] != end;
203 }
204 
205 /* reg must be MAX_ADDR_CELLS */
206 static int find_range(u32 *reg, u32 *ranges, int nregaddr,
207  int naddr, int nsize, int buflen)
208 {
209  int nrange = nregaddr + naddr + nsize;
210  int i;
211 
212  for (i = 0; i + nrange <= buflen; i += nrange) {
213  u32 range_addr[MAX_ADDR_CELLS];
215 
216  copy_val(range_addr, ranges + i, nregaddr);
217  copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
218 
219  if (compare_reg(reg, range_addr, range_size))
220  return i;
221  }
222 
223  return -1;
224 }
225 
226 /* Currently only generic buses without special encodings are supported.
227  * In particular, PCI is not supported. Also, only the beginning of the
228  * reg block is tracked; size is ignored except in ranges.
229  */
230 static u32 prop_buf[MAX_PROP_LEN / 4];
231 
232 static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
233  unsigned long *size)
234 {
235  u32 last_addr[MAX_ADDR_CELLS];
236  u32 this_addr[MAX_ADDR_CELLS];
237  void *parent;
238  u64 ret_addr, ret_size;
239  u32 naddr, nsize, prev_naddr, prev_nsize;
240  int buflen, offset;
241 
242  parent = get_parent(node);
243  if (!parent)
244  return 0;
245 
246  dt_get_reg_format(parent, &naddr, &nsize);
247 
248  if (nsize > 2)
249  return 0;
250 
251  offset = (naddr + nsize) * res;
252 
253  if (reglen < offset + naddr + nsize ||
254  MAX_PROP_LEN < (offset + naddr + nsize) * 4)
255  return 0;
256 
257  copy_val(last_addr, prop_buf + offset, naddr);
258 
259  ret_size = prop_buf[offset + naddr];
260  if (nsize == 2) {
261  ret_size <<= 32;
262  ret_size |= prop_buf[offset + naddr + 1];
263  }
264 
265  for (;;) {
266  prev_naddr = naddr;
267  prev_nsize = nsize;
268  node = parent;
269 
270  parent = get_parent(node);
271  if (!parent)
272  break;
273 
274  dt_get_reg_format(parent, &naddr, &nsize);
275 
276  buflen = getprop(node, "ranges", prop_buf,
277  sizeof(prop_buf));
278  if (buflen == 0)
279  continue;
280  if (buflen < 0 || buflen > sizeof(prop_buf))
281  return 0;
282 
283  offset = find_range(last_addr, prop_buf, prev_naddr,
284  naddr, prev_nsize, buflen / 4);
285 
286  if (offset < 0)
287  return 0;
288 
289  copy_val(this_addr, prop_buf + offset, prev_naddr);
290 
291  if (!sub_reg(last_addr, this_addr))
292  return 0;
293 
294  copy_val(this_addr, prop_buf + offset + prev_naddr, naddr);
295 
296  if (!add_reg(last_addr, this_addr, naddr))
297  return 0;
298  }
299 
300  if (naddr > 2)
301  return 0;
302 
303  ret_addr = ((u64)last_addr[2] << 32) | last_addr[3];
304 
305  if (sizeof(void *) == 4 &&
306  (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
307  ret_addr + ret_size > 0x100000000ULL))
308  return 0;
309 
310  *addr = ret_addr;
311  if (size)
312  *size = ret_size;
313 
314  return 1;
315 }
316 
317 int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
318 {
319  int reglen;
320 
321  reglen = getprop(node, "reg", prop_buf, sizeof(prop_buf)) / 4;
322  return dt_xlate(node, res, reglen, addr, size);
323 }
324 
325 int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
326 {
327 
328  if (buflen > sizeof(prop_buf))
329  return 0;
330 
331  memcpy(prop_buf, buf, buflen);
332  return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
333 }
334 
335 int dt_is_compatible(void *node, const char *compat)
336 {
337  char *buf = (char *)prop_buf;
338  int len, pos;
339 
340  len = getprop(node, "compatible", buf, MAX_PROP_LEN);
341  if (len < 0)
342  return 0;
343 
344  for (pos = 0; pos < len; pos++) {
345  if (!strcmp(buf + pos, compat))
346  return 1;
347 
348  pos += strnlen(&buf[pos], len - pos);
349  }
350 
351  return 0;
352 }
353 
354 int dt_get_virtual_reg(void *node, void **addr, int nres)
355 {
356  unsigned long xaddr;
357  int n;
358 
359  n = getprop(node, "virtual-reg", addr, nres * 4);
360  if (n > 0)
361  return n / 4;
362 
363  for (n = 0; n < nres; n++) {
364  if (!dt_xlate_reg(node, n, &xaddr, NULL))
365  break;
366 
367  addr[n] = (void *)xaddr;
368  }
369 
370  return n;
371 }
372