1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 Google, Inc
4  * Written by Simon Glass <sjg@chromium.org>
5  */
6 
7 #include <common.h>
8 #include <errno.h>
9 #include <image.h>
10 #include <log.h>
11 #include <linux/libfdt.h>
12 
fdt_getprop_u32(const void * fdt,int node,const char * prop)13 ulong fdt_getprop_u32(const void *fdt, int node, const char *prop)
14 {
15 	const u32 *cell;
16 	int len;
17 
18 	cell = fdt_getprop(fdt, node, prop, &len);
19 	if (!cell || len != sizeof(*cell))
20 		return FDT_ERROR;
21 
22 	return fdt32_to_cpu(*cell);
23 }
24 
board_fit_config_name_match(const char * name)25 __weak int board_fit_config_name_match(const char *name)
26 {
27 	return -EINVAL;
28 }
29 
30 /*
31  * Iterate over all /configurations subnodes and call a platform specific
32  * function to find the matching configuration.
33  * Returns the node offset or a negative error number.
34  */
fit_find_config_node(const void * fdt)35 int fit_find_config_node(const void *fdt)
36 {
37 	const char *name;
38 	int conf, node, len;
39 	const char *dflt_conf_name;
40 	const char *dflt_conf_desc = NULL;
41 	int dflt_conf_node = -ENOENT;
42 
43 	conf = fdt_path_offset(fdt, FIT_CONFS_PATH);
44 	if (conf < 0) {
45 		debug("%s: Cannot find /configurations node: %d\n", __func__,
46 		      conf);
47 		return -EINVAL;
48 	}
49 
50 	dflt_conf_name = fdt_getprop(fdt, conf, "default", &len);
51 
52 	for (node = fdt_first_subnode(fdt, conf);
53 	     node >= 0;
54 	     node = fdt_next_subnode(fdt, node)) {
55 		name = fdt_getprop(fdt, node, "description", &len);
56 		if (!name) {
57 #ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
58 			printf("%s: Missing FDT description in DTB\n",
59 			       __func__);
60 #endif
61 			return -EINVAL;
62 		}
63 
64 		if (dflt_conf_name) {
65 			const char *node_name = fdt_get_name(fdt, node, NULL);
66 			if (strcmp(dflt_conf_name, node_name) == 0) {
67 				dflt_conf_node = node;
68 				dflt_conf_desc = name;
69 			}
70 		}
71 
72 		if (board_fit_config_name_match(name))
73 			continue;
74 
75 		debug("Selecting config '%s'\n", name);
76 
77 		return node;
78 	}
79 
80 	if (dflt_conf_node != -ENOENT) {
81 		debug("Selecting default config '%s'\n", dflt_conf_desc);
82 		return dflt_conf_node;
83 	}
84 
85 	return -ENOENT;
86 }
87