xref: /linux/arch/powerpc/boot/devtree.c (revision a17627ef8833ac30622a7b39b7be390e1b174405)
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 
79 void dt_fixup_clock(const char *path, u32 freq)
80 {
81 	void *devp = finddevice(path);
82 
83 	if (devp) {
84 		printf("%s: clock-frequency <- %x (%dMHz)\n\r", path, freq, MHZ(freq));
85 		setprop_val(devp, "clock-frequency", freq);
86 	}
87 }
88 
89 void __dt_fixup_mac_addresses(u32 startindex, ...)
90 {
91 	va_list ap;
92 	u32 index = startindex;
93 	void *devp;
94 	const u8 *addr;
95 
96 	va_start(ap, startindex);
97 	while ((addr = va_arg(ap, const u8 *))) {
98 		devp = find_node_by_prop_value(NULL, "linux,network-index",
99 					       (void*)&index, sizeof(index));
100 
101 		printf("ENET%d: local-mac-address <-"
102 		       " %02x:%02x:%02x:%02x:%02x:%02x\n\r", index,
103 		       addr[0], addr[1], addr[2], addr[3], addr[4], addr[5]);
104 
105 		if (devp)
106 			setprop(devp, "local-mac-address", addr, 6);
107 
108 		index++;
109 	}
110 	va_end(ap);
111 }
112 
113 #define MAX_ADDR_CELLS 4
114 #define MAX_RANGES 8
115 
116 static void get_reg_format(void *node, u32 *naddr, u32 *nsize)
117 {
118 	if (getprop(node, "#address-cells", naddr, 4) != 4)
119 		*naddr = 2;
120 	if (getprop(node, "#size-cells", nsize, 4) != 4)
121 		*nsize = 1;
122 }
123 
124 static void copy_val(u32 *dest, u32 *src, int naddr)
125 {
126 	int pad = MAX_ADDR_CELLS - naddr;
127 
128 	memset(dest, 0, pad * 4);
129 	memcpy(dest + pad, src, naddr * 4);
130 }
131 
132 static int sub_reg(u32 *reg, u32 *sub)
133 {
134 	int i, borrow = 0;
135 
136 	for (i = MAX_ADDR_CELLS - 1; i >= 0; i--) {
137 		int prev_borrow = borrow;
138 		borrow = reg[i] < sub[i] + prev_borrow;
139 		reg[i] -= sub[i] + prev_borrow;
140 	}
141 
142 	return !borrow;
143 }
144 
145 static int add_reg(u32 *reg, u32 *add, int naddr)
146 {
147 	int i, carry = 0;
148 
149 	for (i = MAX_ADDR_CELLS - 1; i >= MAX_ADDR_CELLS - naddr; i--) {
150 		u64 tmp = (u64)reg[i] + add[i] + carry;
151 		carry = tmp >> 32;
152 		reg[i] = (u32)tmp;
153 	}
154 
155 	return !carry;
156 }
157 
158 /* It is assumed that if the first byte of reg fits in a
159  * range, then the whole reg block fits.
160  */
161 static int compare_reg(u32 *reg, u32 *range, u32 *rangesize)
162 {
163 	int i;
164 	u32 end;
165 
166 	for (i = 0; i < MAX_ADDR_CELLS; i++) {
167 		if (reg[i] < range[i])
168 			return 0;
169 		if (reg[i] > range[i])
170 			break;
171 	}
172 
173 	for (i = 0; i < MAX_ADDR_CELLS; i++) {
174 		end = range[i] + rangesize[i];
175 
176 		if (reg[i] < end)
177 			break;
178 		if (reg[i] > end)
179 			return 0;
180 	}
181 
182 	return reg[i] != end;
183 }
184 
185 /* reg must be MAX_ADDR_CELLS */
186 static int find_range(u32 *reg, u32 *ranges, int nregaddr,
187                       int naddr, int nsize, int buflen)
188 {
189 	int nrange = nregaddr + naddr + nsize;
190 	int i;
191 
192 	for (i = 0; i + nrange <= buflen; i += nrange) {
193 		u32 range_addr[MAX_ADDR_CELLS];
194 		u32 range_size[MAX_ADDR_CELLS];
195 
196 		copy_val(range_addr, ranges + i, naddr);
197 		copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
198 
199 		if (compare_reg(reg, range_addr, range_size))
200 			return i;
201 	}
202 
203 	return -1;
204 }
205 
206 /* Currently only generic buses without special encodings are supported.
207  * In particular, PCI is not supported.  Also, only the beginning of the
208  * reg block is tracked; size is ignored except in ranges.
209  */
210 static u32 dt_xlate_buf[MAX_ADDR_CELLS * MAX_RANGES * 3];
211 
212 static int dt_xlate(void *node, int res, int reglen, unsigned long *addr,
213 		unsigned long *size)
214 {
215 	u32 last_addr[MAX_ADDR_CELLS];
216 	u32 this_addr[MAX_ADDR_CELLS];
217 	void *parent;
218 	u64 ret_addr, ret_size;
219 	u32 naddr, nsize, prev_naddr;
220 	int buflen, offset;
221 
222 	parent = get_parent(node);
223 	if (!parent)
224 		return 0;
225 
226 	get_reg_format(parent, &naddr, &nsize);
227 
228 	if (nsize > 2)
229 		return 0;
230 
231 	offset = (naddr + nsize) * res;
232 
233 	if (reglen < offset + naddr + nsize ||
234 	    sizeof(dt_xlate_buf) < offset + naddr + nsize)
235 		return 0;
236 
237 	copy_val(last_addr, dt_xlate_buf + offset, naddr);
238 
239 	ret_size = dt_xlate_buf[offset + naddr];
240 	if (nsize == 2) {
241 		ret_size <<= 32;
242 		ret_size |= dt_xlate_buf[offset + naddr + 1];
243 	}
244 
245 	while ((node = get_parent(node))) {
246 		prev_naddr = naddr;
247 
248 		get_reg_format(node, &naddr, &nsize);
249 
250 		buflen = getprop(node, "ranges", dt_xlate_buf,
251 				sizeof(dt_xlate_buf));
252 		if (buflen < 0)
253 			continue;
254 		if (buflen > sizeof(dt_xlate_buf))
255 			return 0;
256 
257 		offset = find_range(last_addr, dt_xlate_buf, prev_naddr,
258 		                    naddr, nsize, buflen / 4);
259 
260 		if (offset < 0)
261 			return 0;
262 
263 		copy_val(this_addr, dt_xlate_buf + offset, prev_naddr);
264 
265 		if (!sub_reg(last_addr, this_addr))
266 			return 0;
267 
268 		copy_val(this_addr, dt_xlate_buf + offset + prev_naddr, naddr);
269 
270 		if (!add_reg(last_addr, this_addr, naddr))
271 			return 0;
272 	}
273 
274 	if (naddr > 2)
275 		return 0;
276 
277 	ret_addr = ((u64)last_addr[2] << 32) | last_addr[3];
278 
279 	if (sizeof(void *) == 4 &&
280 	    (ret_addr >= 0x100000000ULL || ret_size > 0x100000000ULL ||
281 	     ret_addr + ret_size > 0x100000000ULL))
282 		return 0;
283 
284 	*addr = ret_addr;
285 	if (size)
286 		*size = ret_size;
287 
288 	return 1;
289 }
290 
291 int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
292 {
293 	int reglen;
294 
295 	reglen = getprop(node, "reg", dt_xlate_buf, sizeof(dt_xlate_buf)) / 4;
296 	return dt_xlate(node, res, reglen, addr, size);
297 }
298 
299 int dt_xlate_addr(void *node, u32 *buf, int buflen, unsigned long *xlated_addr)
300 {
301 
302 	if (buflen > sizeof(dt_xlate_buf))
303 		return 0;
304 
305 	memcpy(dt_xlate_buf, buf, buflen);
306 	return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
307 }
308