xref: /linux/arch/powerpc/boot/devtree.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe) 
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 <david@gibson.dropbear.id.au>
7  *	    Scott Wood <scottwood@freescale.com>
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 
21 void dt_fixup_memory(u64 start, u64 size)
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 
62 void dt_fixup_cpu_clocks(u32 cpu, u32 tb, u32 bus)
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 
105 void dt_fixup_mac_address(u32 index, const u8 *addr)
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];
214 		u32 range_size[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 
373