1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * devtree.c - convenience functions for device tree manipulation
4 * Copyright 2007 David Gibson, IBM Corporation.
5 * Copyright (c) 2007 Freescale Semiconductor, Inc.
6 *
7 * Authors: David Gibson <david@gibson.dropbear.id.au>
8 * Scott Wood <scottwood@freescale.com>
9 */
10#include <stdarg.h>
11#include <stddef.h>
12#include "types.h"
13#include "string.h"
14#include "stdio.h"
15#include "ops.h"
16#include "of.h"
17
18void dt_fixup_memory(u64 start, u64 size)
19{
20 void *root, *memory;
21 int naddr, nsize, i;
22 u32 memreg[4];
23
24 root = finddevice(name: "/");
25 if (getprop(devp: root, name: "#address-cells", buf: &naddr, buflen: sizeof(naddr)) < 0)
26 naddr = 2;
27 else
28 naddr = be32_to_cpu(naddr);
29 if (naddr < 1 || naddr > 2)
30 fatal("Can't cope with #address-cells == %d in /\n\r", naddr);
31
32 if (getprop(devp: root, name: "#size-cells", buf: &nsize, buflen: sizeof(nsize)) < 0)
33 nsize = 1;
34 else
35 nsize = be32_to_cpu(nsize);
36 if (nsize < 1 || nsize > 2)
37 fatal("Can't cope with #size-cells == %d in /\n\r", nsize);
38
39 i = 0;
40 if (naddr == 2)
41 memreg[i++] = cpu_to_be32(start >> 32);
42 memreg[i++] = cpu_to_be32(start & 0xffffffff);
43 if (nsize == 2)
44 memreg[i++] = cpu_to_be32(size >> 32);
45 memreg[i++] = cpu_to_be32(size & 0xffffffff);
46
47 memory = finddevice(name: "/memory");
48 if (! memory) {
49 memory = create_node(parent: NULL, name: "memory");
50 setprop_str(devp: memory, name: "device_type", buf: "memory");
51 }
52
53 printf(fmt: "Memory <- <0x%x", be32_to_cpu(memreg[0]));
54 for (i = 1; i < (naddr + nsize); i++)
55 printf(fmt: " 0x%x", be32_to_cpu(memreg[i]));
56 printf(fmt: "> (%ldMB)\n\r", (unsigned long)(size >> 20));
57
58 setprop(devp: memory, name: "reg", buf: memreg, buflen: (naddr + nsize)*sizeof(u32));
59}
60
61#define MHZ(x) ((x + 500000) / 1000000)
62
63void dt_fixup_cpu_clocks(u32 cpu, u32 tb, u32 bus)
64{
65 void *devp = NULL;
66
67 printf(fmt: "CPU clock-frequency <- 0x%x (%dMHz)\n\r", cpu, MHZ(cpu));
68 printf(fmt: "CPU timebase-frequency <- 0x%x (%dMHz)\n\r", tb, MHZ(tb));
69 if (bus > 0)
70 printf(fmt: "CPU bus-frequency <- 0x%x (%dMHz)\n\r", bus, MHZ(bus));
71
72 while ((devp = find_node_by_devtype(prev: devp, type: "cpu"))) {
73 setprop_val(devp, "clock-frequency", cpu_to_be32(cpu));
74 setprop_val(devp, "timebase-frequency", cpu_to_be32(tb));
75 if (bus > 0)
76 setprop_val(devp, "bus-frequency", cpu_to_be32(bus));
77 }
78
79 timebase_period_ns = 1000000000 / tb;
80}
81
82void dt_fixup_clock(const char *path, u32 freq)
83{
84 void *devp = finddevice(name: path);
85
86 if (devp) {
87 printf(fmt: "%s: clock-frequency <- %x (%dMHz)\n\r", path, freq, MHZ(freq));
88 setprop_val(devp, "clock-frequency", cpu_to_be32(freq));
89 }
90}
91
92void dt_fixup_mac_address_by_alias(const char *alias, const u8 *addr)
93{
94 void *devp = find_node_by_alias(alias);
95
96 if (devp) {
97 printf(fmt: "%s: local-mac-address <-"
98 " %02x:%02x:%02x:%02x:%02x:%02x\n\r", alias,
99 addr[0], addr[1], addr[2],
100 addr[3], addr[4], addr[5]);
101
102 setprop(devp, name: "local-mac-address", buf: addr, buflen: 6);
103 }
104}
105
106void dt_fixup_mac_address(u32 index, const u8 *addr)
107{
108 void *devp = find_node_by_prop_value(prev: NULL, propname: "linux,network-index",
109 propval: (void*)&index, proplen: sizeof(index));
110
111 if (devp) {
112 printf(fmt: "ENET%d: local-mac-address <-"
113 " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
114 addr[0], addr[1], addr[2],
115 addr[3], addr[4], addr[5]);
116
117 setprop(devp, name: "local-mac-address", buf: addr, buflen: 6);
118 }
119}
120
121void __dt_fixup_mac_addresses(u32 startindex, ...)
122{
123 va_list ap;
124 u32 index = startindex;
125 const u8 *addr;
126
127 va_start(ap, startindex);
128
129 while ((addr = va_arg(ap, const u8 *)))
130 dt_fixup_mac_address(index: index++, addr);
131
132 va_end(ap);
133}
134
135#define MAX_ADDR_CELLS 4
136
137void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)
138{
139 if (getprop(devp: node, name: "#address-cells", buf: naddr, buflen: 4) != 4)
140 *naddr = 2;
141 else
142 *naddr = be32_to_cpu(*naddr);
143 if (getprop(devp: node, name: "#size-cells", buf: nsize, buflen: 4) != 4)
144 *nsize = 1;
145 else
146 *nsize = be32_to_cpu(*nsize);
147}
148
149static void copy_val(u32 *dest, u32 *src, int naddr)
150{
151 int pad = MAX_ADDR_CELLS - naddr;
152
153 memset(dest, 0, pad * 4);
154 memcpy(dest: dest + pad, src, n: naddr * 4);
155}
156
157static int sub_reg(u32 *reg, u32 *sub)
158{
159 int i, borrow = 0;
160
161 for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {
162 int prev_borrow = borrow;
163 borrow = reg[i] < sub[i] + prev_borrow;
164 reg[i] -= sub[i] + prev_borrow;
165 }
166
167 return !borrow;
168}
169
170static int add_reg(u32 *reg, u32 *add, int naddr)
171{
172 int i, carry = 0;
173
174 for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {
175 u64 tmp = (u64)be32_to_cpu(reg[i]) + be32_to_cpu(add[i]) + carry;
176 carry = tmp >> 32;
177 reg[i] = cpu_to_be32((u32)tmp);
178 }
179
180 return !carry;
181}
182
183/* It is assumed that if the first byte of reg fits in a
184 * range, then the whole reg block fits.
185 */
186static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
187{
188 int i;
189 u32 end;
190
191 for (i = 0; i < MAX_ADDR_CELLS; i++) {
192 if (be32_to_cpu(reg[i]) < be32_to_cpu(range[i]))
193 return 0;
194 if (be32_to_cpu(reg[i]) > be32_to_cpu(range[i]))
195 break;
196 }
197
198 for (i = 0; i < MAX_ADDR_CELLS; i++) {
199 end = be32_to_cpu(range[i]) + be32_to_cpu(rangesize[i]);
200
201 if (be32_to_cpu(reg[i]) < end)
202 break;
203 if (be32_to_cpu(reg[i]) > end)
204 return 0;
205 }
206
207 return reg[i] != end;
208}
209
210/* reg must be MAX_ADDR_CELLS */
211static int find_range(u32 *reg, u32 *ranges, int nregaddr,
212 int naddr, int nsize, int buflen)
213{
214 int nrange = nregaddr + naddr + nsize;
215 int i;
216
217 for (i = 0; i + nrange <= buflen; i += nrange) {
218 u32 range_addr[MAX_ADDR_CELLS];
219 u32 range_size[MAX_ADDR_CELLS];
220
221 copy_val(dest: range_addr, src: ranges + i, naddr: nregaddr);
222 copy_val(dest: range_size, src: ranges + i + nregaddr + naddr, naddr: nsize);
223
224 if (compare_reg(reg, range: range_addr, rangesize: range_size))
225 return i;
226 }
227
228 return -1;
229}
230
231/* Currently only generic buses without special encodings are supported.
232 * In particular, PCI is not supported. Also, only the beginning of the
233 * reg block is tracked; size is ignored except in ranges.
234 */
235static u32 prop_buf[MAX_PROP_LEN / 4];
236
237static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
238 unsigned long *size)
239{
240 u32 last_addr[MAX_ADDR_CELLS];
241 u32 this_addr[MAX_ADDR_CELLS];
242 void *parent;
243 u64 ret_addr, ret_size;
244 u32 naddr, nsize, prev_naddr, prev_nsize;
245 int buflen, offset;
246
247 parent = get_parent(devp: node);
248 if (!parent)
249 return 0;
250
251 dt_get_reg_format(node: parent, naddr: &naddr, nsize: &nsize);
252 if (nsize > 2)
253 return 0;
254
255 offset = (naddr + nsize) * res;
256
257 if (reglen < offset + naddr + nsize ||
258 MAX_PROP_LEN < (offset + naddr + nsize) * 4)
259 return 0;
260
261 copy_val(dest: last_addr, src: prop_buf + offset, naddr);
262
263 ret_size = be32_to_cpu(prop_buf[offset + naddr]);
264 if (nsize == 2) {
265 ret_size <<= 32;
266 ret_size |= be32_to_cpu(prop_buf[offset + naddr + 1]);
267 }
268
269 for (;;) {
270 prev_naddr = naddr;
271 prev_nsize = nsize;
272 node = parent;
273
274 parent = get_parent(devp: node);
275 if (!parent)
276 break;
277
278 dt_get_reg_format(node: parent, naddr: &naddr, nsize: &nsize);
279
280 buflen = getprop(devp: node, name: "ranges", buf: prop_buf,
281 buflen: sizeof(prop_buf));
282 if (buflen == 0)
283 continue;
284 if (buflen < 0 || buflen > sizeof(prop_buf))
285 return 0;
286
287 offset = find_range(reg: last_addr, ranges: prop_buf, nregaddr: prev_naddr,
288 naddr, nsize: prev_nsize, buflen: buflen / 4);
289 if (offset < 0)
290 return 0;
291
292 copy_val(dest: this_addr, src: prop_buf + offset, naddr: prev_naddr);
293
294 if (!sub_reg(reg: last_addr, sub: this_addr))
295 return 0;
296
297 copy_val(dest: this_addr, src: prop_buf + offset + prev_naddr, naddr);
298
299 if (!add_reg(reg: last_addr, add: this_addr, naddr))
300 return 0;
301 }
302
303 if (naddr > 2)
304 return 0;
305
306 ret_addr = ((u64)be32_to_cpu(last_addr[2]) << 32) | be32_to_cpu(last_addr[3]);
307 if (sizeof(void *) == 4 &&
308 (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
309 ret_addr + ret_size > 0x100000000ULL))
310 return 0;
311
312 *addr = ret_addr;
313 if (size)
314 *size = ret_size;
315
316 return 1;
317}
318
319int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
320{
321 int reglen;
322
323 reglen = getprop(devp: node, name: "reg", buf: prop_buf, buflen: sizeof(prop_buf)) / 4;
324 return dt_xlate(node, res, reglen, addr, size);
325}
326
327int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
328{
329
330 if (buflen > sizeof(prop_buf))
331 return 0;
332
333 memcpy(dest: prop_buf, src: buf, n: buflen);
334 return dt_xlate(node, res: 0, reglen: buflen / 4, addr: xlated_addr, size: NULL);
335}
336
337int dt_is_compatible(void *node, const char *compat)
338{
339 char *buf = (char *)prop_buf;
340 int len, pos;
341
342 len = getprop(devp: node, name: "compatible", buf, MAX_PROP_LEN);
343 if (len < 0)
344 return 0;
345
346 for (pos = 0; pos < len; pos++) {
347 if (!strcmp(s1: buf + pos, s2: compat))
348 return 1;
349
350 pos += strnlen(&buf[pos], len - pos);
351 }
352
353 return 0;
354}
355
356int dt_get_virtual_reg(void *node, void **addr, int nres)
357{
358 unsigned long xaddr;
359 int n, i;
360
361 n = getprop(devp: node, name: "virtual-reg", buf: addr, buflen: nres * 4);
362 if (n > 0) {
363 for (i = 0; i < n/4; i ++)
364 ((u32 *)addr)[i] = be32_to_cpu(((u32 *)addr)[i]);
365 return n / 4;
366 }
367
368 for (n = 0; n < nres; n++) {
369 if (!dt_xlate_reg(node, res: n, addr: &xaddr, size: NULL))
370 break;
371
372 addr[n] = (void *)xaddr;
373 }
374
375 return n;
376}
377
378

source code of linux/arch/powerpc/boot/devtree.c