devtree.c revision 96ebc3bfb6ddedd5a400d5653b50551d5a3de439 
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
21void 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
62void 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
81void 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
91void __dt_fixup_mac_addresses(u32 startindex, ...)
92{
93	va_list ap;
94	u32 index = startindex;
95	void *devp;
96	const u8 *addr;
97
98	va_start(ap, startindex);
99	while ((addr = va_arg(ap, const u8 *))) {
100		devp = find_node_by_prop_value(NULL, "linux,network-index",
101					       (void*)&index, sizeof(index));
102
103		if (devp) {
104			printf("ENET%d: local-mac-address <-"
105			       " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
106			       addr[0], addr[1], addr[2],
107			       addr[3], addr[4], addr[5]);
108
109			setprop(devp, "local-mac-address", addr, 6);
110		}
111
112		index++;
113	}
114	va_end(ap);
115}
116
117#define MAX_ADDR_CELLS 4
118
119void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)
120{
121	if (getprop(node, "#address-cells", naddr, 4) != 4)
122		*naddr = 2;
123	if (getprop(node, "#size-cells", nsize, 4) != 4)
124		*nsize = 1;
125}
126
127static void copy_val(u32 *dest, u32 *src, int naddr)
128{
129	int pad = MAX_ADDR_CELLS - naddr;
130
131	memset(dest, 0, pad * 4);
132	memcpy(dest + pad, src, naddr * 4);
133}
134
135static int sub_reg(u32 *reg, u32 *sub)
136{
137	int i, borrow = 0;
138
139	for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {
140		int prev_borrow = borrow;
141		borrow = reg[i] < sub[i] + prev_borrow;
142		reg[i] -= sub[i] + prev_borrow;
143	}
144
145	return !borrow;
146}
147
148static int add_reg(u32 *reg, u32 *add, int naddr)
149{
150	int i, carry = 0;
151
152	for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {
153		u64 tmp = (u64)reg[i] + add[i] + carry;
154		carry = tmp >> 32;
155		reg[i] = (u32)tmp;
156	}
157
158	return !carry;
159}
160
161/* It is assumed that if the first byte of reg fits in a
162 * range, then the whole reg block fits.
163 */
164static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
165{
166	int i;
167	u32 end;
168
169	for (i = 0; i < MAX_ADDR_CELLS; i++) {
170		if (reg[i] < range[i])
171			return 0;
172		if (reg[i] > range[i])
173			break;
174	}
175
176	for (i = 0; i < MAX_ADDR_CELLS; i++) {
177		end = range[i] + rangesize[i];
178
179		if (reg[i] < end)
180			break;
181		if (reg[i] > end)
182			return 0;
183	}
184
185	return reg[i] != end;
186}
187
188/* reg must be MAX_ADDR_CELLS */
189static int find_range(u32 *reg, u32 *ranges, int nregaddr,
190                      int naddr, int nsize, int buflen)
191{
192	int nrange = nregaddr + naddr + nsize;
193	int i;
194
195	for (i = 0; i + nrange <= buflen; i += nrange) {
196		u32 range_addr[MAX_ADDR_CELLS];
197		u32 range_size[MAX_ADDR_CELLS];
198
199		copy_val(range_addr, ranges + i, naddr);
200		copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
201
202		if (compare_reg(reg, range_addr, range_size))
203			return i;
204	}
205
206	return -1;
207}
208
209/* Currently only generic buses without special encodings are supported.
210 * In particular, PCI is not supported.  Also, only the beginning of the
211 * reg block is tracked; size is ignored except in ranges.
212 */
213static u32 prop_buf[MAX_PROP_LEN / 4];
214
215static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
216		unsigned long *size)
217{
218	u32 last_addr[MAX_ADDR_CELLS];
219	u32 this_addr[MAX_ADDR_CELLS];
220	void *parent;
221	u64 ret_addr, ret_size;
222	u32 naddr, nsize, prev_naddr, prev_nsize;
223	int buflen, offset;
224
225	parent = get_parent(node);
226	if (!parent)
227		return 0;
228
229	dt_get_reg_format(parent, &naddr, &nsize);
230
231	if (nsize > 2)
232		return 0;
233
234	offset = (naddr + nsize) * res;
235
236	if (reglen < offset + naddr + nsize ||
237	    MAX_PROP_LEN < (offset + naddr + nsize) * 4)
238		return 0;
239
240	copy_val(last_addr, prop_buf + offset, naddr);
241
242	ret_size = prop_buf[offset + naddr];
243	if (nsize == 2) {
244		ret_size <<= 32;
245		ret_size |= prop_buf[offset + naddr + 1];
246	}
247
248	for (;;) {
249		prev_naddr = naddr;
250		prev_nsize = nsize;
251		node = parent;
252
253		parent = get_parent(node);
254		if (!parent)
255			break;
256
257		dt_get_reg_format(parent, &naddr, &nsize);
258
259		buflen = getprop(node, "ranges", prop_buf,
260				sizeof(prop_buf));
261		if (buflen == 0)
262			continue;
263		if (buflen < 0 || buflen > sizeof(prop_buf))
264			return 0;
265
266		offset = find_range(last_addr, prop_buf, prev_naddr,
267		                    naddr, prev_nsize, buflen / 4);
268
269		if (offset < 0)
270			return 0;
271
272		copy_val(this_addr, prop_buf + offset, prev_naddr);
273
274		if (!sub_reg(last_addr, this_addr))
275			return 0;
276
277		copy_val(this_addr, prop_buf + offset + prev_naddr, naddr);
278
279		if (!add_reg(last_addr, this_addr, naddr))
280			return 0;
281	}
282
283	if (naddr > 2)
284		return 0;
285
286	ret_addr = ((u64)last_addr[2] << 32) | last_addr[3];
287
288	if (sizeof(void *) == 4 &&
289	    (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
290	     ret_addr + ret_size > 0x100000000ULL))
291		return 0;
292
293	*addr = ret_addr;
294	if (size)
295		*size = ret_size;
296
297	return 1;
298}
299
300int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
301{
302	int reglen;
303
304	reglen = getprop(node, "reg", prop_buf, sizeof(prop_buf)) / 4;
305	return dt_xlate(node, res, reglen, addr, size);
306}
307
308int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
309{
310
311	if (buflen > sizeof(prop_buf))
312		return 0;
313
314	memcpy(prop_buf, buf, buflen);
315	return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
316}
317
318int dt_is_compatible(void *node, const char *compat)
319{
320	char *buf = (char *)prop_buf;
321	int len, pos;
322
323	len = getprop(node, "compatible", buf, MAX_PROP_LEN);
324	if (len < 0)
325		return 0;
326
327	for (pos = 0; pos < len; pos++) {
328		if (!strcmp(buf + pos, compat))
329			return 1;
330
331		pos += strnlen(&buf[pos], len - pos);
332	}
333
334	return 0;
335}
336