xref: /linux/arch/powerpc/boot/devtree.c (revision cf21f328fcafacf4f96e7a30ef9dceede1076378)
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 
18 void 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("/");
25 	if (getprop(root, "#address-cells", &naddr, 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(root, "#size-cells", &nsize, 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("/memory");
48 	if (! memory) {
49 		memory = create_node(NULL, "memory");
50 		setprop_str(memory, "device_type", "memory");
51 	}
52 
53 	printf("Memory <- <0x%x", be32_to_cpu(memreg[0]));
54 	for (i = 1; i < (naddr + nsize); i++)
55 		printf(" 0x%x", be32_to_cpu(memreg[i]));
56 	printf("> (%ldMB)\n\r", (unsigned long)(size >> 20));
57 
58 	setprop(memory, "reg", memreg, (naddr + nsize)*sizeof(u32));
59 }
60 
61 #define MHZ(x)	((x + 500000) / 1000000)
62 
63 void dt_fixup_cpu_clocks(u32 cpu, u32 tb, u32 bus)
64 {
65 	void *devp = NULL;
66 
67 	printf("CPU clock-frequency <- 0x%x (%dMHz)\n\r", cpu, MHZ(cpu));
68 	printf("CPU timebase-frequency <- 0x%x (%dMHz)\n\r", tb, MHZ(tb));
69 	if (bus > 0)
70 		printf("CPU bus-frequency <- 0x%x (%dMHz)\n\r", bus, MHZ(bus));
71 
72 	while ((devp = find_node_by_devtype(devp, "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 
82 void dt_fixup_clock(const char *path, u32 freq)
83 {
84 	void *devp = finddevice(path);
85 
86 	if (devp) {
87 		printf("%s: clock-frequency <- %x (%dMHz)\n\r", path, freq, MHZ(freq));
88 		setprop_val(devp, "clock-frequency", cpu_to_be32(freq));
89 	}
90 }
91 
92 void 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("%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, "local-mac-address", addr, 6);
103 	}
104 }
105 
106 void dt_fixup_mac_address(u32 index, const u8 *addr)
107 {
108 	void *devp = find_node_by_prop_value(NULL, "linux,network-index",
109 	                                     (void*)&index, sizeof(index));
110 
111 	if (devp) {
112 		printf("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, "local-mac-address", addr, 6);
118 	}
119 }
120 
121 void __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++, addr);
131 
132 	va_end(ap);
133 }
134 
135 #define MAX_ADDR_CELLS 4
136 
137 void dt_get_reg_format(void *node, u32 *naddr, u32 *nsize)
138 {
139 	if (getprop(node, "#address-cells", naddr, 4) != 4)
140 		*naddr = 2;
141 	else
142 		*naddr = be32_to_cpu(*naddr);
143 	if (getprop(node, "#size-cells", nsize, 4) != 4)
144 		*nsize = 1;
145 	else
146 		*nsize = be32_to_cpu(*nsize);
147 }
148 
149 static 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 + pad, src, naddr * 4);
155 }
156 
157 static 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 
170 static 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  */
186 static 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 */
211 static 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(range_addr, ranges + i, nregaddr);
222 		copy_val(range_size, ranges + i + nregaddr + naddr, nsize);
223 
224 		if (compare_reg(reg, range_addr, 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  */
235 static u32 prop_buf[MAX_PROP_LEN / 4];
236 
237 static 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(node);
248 	if (!parent)
249 		return 0;
250 
251 	dt_get_reg_format(parent, &naddr, &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(last_addr, 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(node);
275 		if (!parent)
276 			break;
277 
278 		dt_get_reg_format(parent, &naddr, &nsize);
279 
280 		buflen = getprop(node, "ranges", prop_buf,
281 				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(last_addr, prop_buf, prev_naddr,
288 		                    naddr, prev_nsize, buflen / 4);
289 		if (offset < 0)
290 			return 0;
291 
292 		copy_val(this_addr, prop_buf + offset, prev_naddr);
293 
294 		if (!sub_reg(last_addr, this_addr))
295 			return 0;
296 
297 		copy_val(this_addr, prop_buf + offset + prev_naddr, naddr);
298 
299 		if (!add_reg(last_addr, 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 
319 int dt_xlate_reg(void *node, int res, unsigned long *addr, unsigned long *size)
320 {
321 	int reglen;
322 
323 	reglen = getprop(node, "reg", prop_buf, sizeof(prop_buf)) / 4;
324 	return dt_xlate(node, res, reglen, addr, size);
325 }
326 
327 int 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(prop_buf, buf, buflen);
334 	return dt_xlate(node, 0, buflen / 4, xlated_addr, NULL);
335 }
336 
337 int dt_is_compatible(void *node, const char *compat)
338 {
339 	char *buf = (char *)prop_buf;
340 	int len, pos;
341 
342 	len = getprop(node, "compatible", buf, MAX_PROP_LEN);
343 	if (len < 0)
344 		return 0;
345 
346 	for (pos = 0; pos < len; pos++) {
347 		if (!strcmp(buf + pos, compat))
348 			return 1;
349 
350 		pos += strnlen(&buf[pos], len - pos);
351 	}
352 
353 	return 0;
354 }
355 
356 int dt_get_virtual_reg(void *node, void **addr, int nres)
357 {
358 	unsigned long xaddr;
359 	int n, i;
360 
361 	n = getprop(node, "virtual-reg", addr, 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, n, &xaddr, NULL))
370 			break;
371 
372 		addr[n] = (void *)xaddr;
373 	}
374 
375 	return n;
376 }
377 
378