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
18void 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
63void 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
82void 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
92void 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
106void 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
121void __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
137void 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
149static 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
157static 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
170static 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 */
186static 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 */
211static 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 */
235static u32 prop_buf[MAX_PROP_LEN / 4];
236
237static 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
319int 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
327int 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
337int 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
356int 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