xref: /openbmc/linux/arch/powerpc/boot/devtree.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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(u32 index, const u8 *addr)
92 {
93 	void *devp = find_node_by_prop_value(NULL, "linux,network-index",
94 	                                     (void*)&index, sizeof(index));
95 
96 	if (devp) {
97 		printf("ENET%d: local-mac-address <-"
98 		       " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
99 		       addr[0], addr[1], addr[2],
100 		       addr[3], addr[4], addr[5]);
101 
102 		setprop(devp, "local-mac-address", addr, 6);
103 	}
104 }
105 
106 void __dt_fixup_mac_addresses(u32 startindex, ...)
107 {
108 	va_list ap;
109 	u32 index = startindex;
110 	const u8 *addr;
111 
112 	va_start(ap, startindex);
113 
114 	while ((addr = va_arg(ap, const u8 *)))
115 		dt_fixup_mac_address(index++, addr);
116 
117 	va_end(ap);
118 }
119 
120 #define MAX_ADDR_CELLS 4
121 
122 void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)
123 {
124 	if (getprop(node, "#address-cells", naddr, 4) != 4)
125 		*naddr = 2;
126 	if (getprop(node, "#size-cells", nsize, 4) != 4)
127 		*nsize = 1;
128 }
129 
130 static void copy_val(u32 *dest, u32 *src, int naddr)
131 {
132 	int pad = MAX_ADDR_CELLS - naddr;
133 
134 	memset(dest, 0, pad * 4);
135 	memcpy(dest + pad, src, naddr * 4);
136 }
137 
138 static int sub_reg(u32 *reg, u32 *sub)
139 {
140 	int i, borrow = 0;
141 
142 	for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {
143 		int prev_borrow = borrow;
144 		borrow = reg[i] < sub[i] + prev_borrow;
145 		reg[i] -= sub[i] + prev_borrow;
146 	}
147 
148 	return !borrow;
149 }
150 
151 static int add_reg(u32 *reg, u32 *add, int naddr)
152 {
153 	int i, carry = 0;
154 
155 	for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {
156 		u64 tmp = (u64)reg[i] + add[i] + carry;
157 		carry = tmp >> 32;
158 		reg[i] = (u32)tmp;
159 	}
160 
161 	return !carry;
162 }
163 
164 /* It is assumed that if the first byte of reg fits in a
165  * range, then the whole reg block fits.
166  */
167 static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
168 {
169 	int i;
170 	u32 end;
171 
172 	for (i = 0; i < MAX_ADDR_CELLS; i++) {
173 		if (reg[i] < range[i])
174 			return 0;
175 		if (reg[i] > range[i])
176 			break;
177 	}
178 
179 	for (i = 0; i < MAX_ADDR_CELLS; i++) {
180 		end = range[i] + rangesize[i];
181 
182 		if (reg[i] < end)
183 			break;
184 		if (reg[i] > end)
185 			return 0;
186 	}
187 
188 	return reg[i] != end;
189 }
190 
191 /* reg must be MAX_ADDR_CELLS */
192 static int find_range(u32 *reg, u32 *ranges, int nregaddr,
193                       int naddr, int nsize, int buflen)
194 {
195 	int nrange = nregaddr + naddr + nsize;
196 	int i;
197 
198 	for (i = 0; i + nrange <= buflen; i += nrange) {
199 		u32 range_addr[MAX_ADDR_CELLS];
200 		u32 range_size[MAX_ADDR_CELLS];
201 
202 		copy_val(range_addr, ranges + i, naddr);
203 		copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
204 
205 		if (compare_reg(reg, range_addr, range_size))
206 			return i;
207 	}
208 
209 	return -1;
210 }
211 
212 /* Currently only generic buses without special encodings are supported.
213  * In particular, PCI is not supported.  Also, only the beginning of the
214  * reg block is tracked; size is ignored except in ranges.
215  */
216 static u32 prop_buf[MAX_PROP_LEN / 4];
217 
218 static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
219 		unsigned long *size)
220 {
221 	u32 last_addr[MAX_ADDR_CELLS];
222 	u32 this_addr[MAX_ADDR_CELLS];
223 	void *parent;
224 	u64 ret_addr, ret_size;
225 	u32 naddr, nsize, prev_naddr, prev_nsize;
226 	int buflen, offset;
227 
228 	parent = get_parent(node);
229 	if (!parent)
230 		return 0;
231 
232 	dt_get_reg_format(parent, &naddr, &nsize);
233 
234 	if (nsize > 2)
235 		return 0;
236 
237 	offset = (naddr + nsize) * res;
238 
239 	if (reglen < offset + naddr + nsize ||
240 	    MAX_PROP_LEN < (offset + naddr + nsize) * 4)
241 		return 0;
242 
243 	copy_val(last_addr, prop_buf + offset, naddr);
244 
245 	ret_size = prop_buf[offset + naddr];
246 	if (nsize == 2) {
247 		ret_size <<= 32;
248 		ret_size |= prop_buf[offset + naddr + 1];
249 	}
250 
251 	for (;;) {
252 		prev_naddr = naddr;
253 		prev_nsize = nsize;
254 		node = parent;
255 
256 		parent = get_parent(node);
257 		if (!parent)
258 			break;
259 
260 		dt_get_reg_format(parent, &naddr, &nsize);
261 
262 		buflen = getprop(node, "ranges", prop_buf,
263 				sizeof(prop_buf));
264 		if (buflen == 0)
265 			continue;
266 		if (buflen < 0 || buflen > sizeof(prop_buf))
267 			return 0;
268 
269 		offset = find_range(last_addr, prop_buf, prev_naddr,
270 		                    naddr, prev_nsize, buflen / 4);
271 
272 		if (offset < 0)
273 			return 0;
274 
275 		copy_val(this_addr, prop_buf + offset, prev_naddr);
276 
277 		if (!sub_reg(last_addr, this_addr))
278 			return 0;
279 
280 		copy_val(this_addr, prop_buf + offset + prev_naddr, naddr);
281 
282 		if (!add_reg(last_addr, this_addr, naddr))
283 			return 0;
284 	}
285 
286 	if (naddr > 2)
287 		return 0;
288 
289 	ret_addr = ((u64)last_addr[2] << 32) | last_addr[3];
290 
291 	if (sizeof(void *) == 4 &&
292 	    (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
293 	     ret_addr + ret_size > 0x100000000ULL))
294 		return 0;
295 
296 	*addr = ret_addr;
297 	if (size)
298 		*size = ret_size;
299 
300 	return 1;
301 }
302 
303 int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
304 {
305 	int reglen;
306 
307 	reglen = getprop(node, "reg", prop_buf, sizeof(prop_buf)) / 4;
308 	return dt_xlate(node, res, reglen, addr, size);
309 }
310 
311 int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
312 {
313 
314 	if (buflen > sizeof(prop_buf))
315 		return 0;
316 
317 	memcpy(prop_buf, buf, buflen);
318 	return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
319 }
320 
321 int dt_is_compatible(void *node, const char *compat)
322 {
323 	char *buf = (char *)prop_buf;
324 	int len, pos;
325 
326 	len = getprop(node, "compatible", buf, MAX_PROP_LEN);
327 	if (len < 0)
328 		return 0;
329 
330 	for (pos = 0; pos < len; pos++) {
331 		if (!strcmp(buf + pos, compat))
332 			return 1;
333 
334 		pos += strnlen(&buf[pos], len - pos);
335 	}
336 
337 	return 0;
338 }
339