1/*	$NetBSD: fdt_ddb.c,v 1.2 2021/03/06 13:21:26 skrll Exp $	*/
2
3/*-
4 * Copyright (c) 2020 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Nick Hudson
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32
33#include <sys/cdefs.h>
34__KERNEL_RCSID(0, "$NetBSD: fdt_ddb.c,v 1.2 2021/03/06 13:21:26 skrll Exp $");
35
36#include <sys/param.h>
37
38#include <libfdt.h>
39#include <dev/fdt/fdt_ddb.h>
40#include <dev/fdt/fdtvar.h>
41
42#define FDT_MAX_DEPTH	16
43
44static bool
45fdt_isprint(const void *data, int len)
46{
47	const uint8_t *c = (const uint8_t *)data;
48
49	if (len == 0)
50		return false;
51
52	/* Count consecutive zeroes */
53	int cz = 0;
54	for (size_t j = 0; j < len; j++) {
55		if (c[j] == '\0')
56			cz++;
57		else if (isprint(c[j]))
58			cz = 0;
59		else
60			return false;
61		if (cz > 1)
62			return false;
63	}
64	return true;
65}
66
67static void
68fdt_print_properties(const void *fdt, int node,
69    void (*pr)(const char *, ...) __printflike(1, 2))
70{
71	int property;
72
73	fdt_for_each_property_offset(property, fdt, node) {
74		int len;
75		const struct fdt_property *prop =
76		    fdt_get_property_by_offset(fdt, property, &len);
77		const char *name = fdt_string(fdt, fdt32_to_cpu(prop->nameoff));
78
79		pr("    %s", name);
80		if (len == 0) {
81			pr("\n");
82			continue;
83		}
84		if (fdt_isprint(prop->data, len)) {
85			const uint8_t *c = (const uint8_t *)prop->data;
86
87			pr(" = \"");
88			for (size_t j = 0; j < len; j++) {
89				if (c[j] == '\0') {
90					if (j + 1 != len)
91						pr("\", \"");
92				} else
93					pr("%c", c[j]);
94			}
95			pr("\"\n");
96			continue;
97		}
98		if ((len % 4) == 0) {
99			const uint32_t *cell = (const uint32_t *)prop->data;
100			size_t count = len / sizeof(uint32_t);
101
102			pr(" = <");
103			for (size_t j = 0; j < count; j++) {
104				pr("%#" PRIx32 "%s", fdt32_to_cpu(cell[j]),
105				    (j != count - 1) ? " " : "");
106			}
107			pr(">\n");
108		} else {
109			const uint8_t *byte = (const uint8_t *)prop->data;
110
111			pr(" = [");
112			for (size_t j = 0; j < len; j++) {
113				pr("%02x%s", byte[j],
114				   (j != len - 1) ? " " : "");
115			}
116			pr("]\n");
117		}
118	}
119}
120
121
122void
123fdt_print(const void *addr, bool full,
124    void (*pr)(const char *, ...) __printflike(1, 2))
125{
126	const void *fdt = addr;
127	const char *pname[FDT_MAX_DEPTH] = { NULL };
128
129	int error = fdt_check_header(fdt);
130	if (error) {
131		pr("Invalid FDT at %p\n", fdt);
132		return;
133	}
134
135	int depth = 0;
136	for (int node = fdt_path_offset(fdt, "/");
137	     node >= 0 && depth >= 0;
138	     node = fdt_next_node(fdt, node, &depth)) {
139		const char *name = fdt_get_name(fdt, node, NULL);
140
141		if (depth > FDT_MAX_DEPTH) {
142			pr("max depth exceeded: %d\n", depth);
143			continue;
144		}
145		pname[depth] = name;
146		/*
147		 * change conditional for when alternative root nodes
148		 * can be specified
149		 */
150		if (depth == 0)
151			pr("/");
152		for (size_t i = 1; i <= depth; i++) {
153			if (pname[i] == NULL)
154				break;
155			pr("/%s", pname[i]);
156		}
157		pr("\n");
158		if (!full)
159			continue;
160		fdt_print_properties(fdt, node, pr);
161	}
162}
163