xref: /openbmc/u-boot/drivers/core/root.c (revision dd580801)
1 /*
2  * Copyright (c) 2013 Google, Inc
3  *
4  * (C) Copyright 2012
5  * Pavel Herrmann <morpheus.ibis@gmail.com>
6  *
7  * SPDX-License-Identifier:	GPL-2.0+
8  */
9 
10 #include <common.h>
11 #include <errno.h>
12 #include <malloc.h>
13 #include <libfdt.h>
14 #include <dm/device.h>
15 #include <dm/device-internal.h>
16 #include <dm/lists.h>
17 #include <dm/platdata.h>
18 #include <dm/root.h>
19 #include <dm/uclass.h>
20 #include <dm/util.h>
21 #include <linux/list.h>
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 static const struct driver_info root_info = {
26 	.name		= "root_driver",
27 };
28 
29 struct udevice *dm_root(void)
30 {
31 	if (!gd->dm_root) {
32 		dm_warn("Virtual root driver does not exist!\n");
33 		return NULL;
34 	}
35 
36 	return gd->dm_root;
37 }
38 
39 int dm_init(void)
40 {
41 	int ret;
42 
43 	if (gd->dm_root) {
44 		dm_warn("Virtual root driver already exists!\n");
45 		return -EINVAL;
46 	}
47 	INIT_LIST_HEAD(&DM_UCLASS_ROOT_NON_CONST);
48 
49 	ret = device_bind_by_name(NULL, false, &root_info, &DM_ROOT_NON_CONST);
50 	if (ret)
51 		return ret;
52 	ret = device_probe(DM_ROOT_NON_CONST);
53 	if (ret)
54 		return ret;
55 
56 	return 0;
57 }
58 
59 int dm_uninit(void)
60 {
61 	device_remove(dm_root());
62 	device_unbind(dm_root());
63 
64 	return 0;
65 }
66 
67 int dm_scan_platdata(bool pre_reloc_only)
68 {
69 	int ret;
70 
71 	ret = lists_bind_drivers(DM_ROOT_NON_CONST, pre_reloc_only);
72 	if (ret == -ENOENT) {
73 		dm_warn("Some drivers were not found\n");
74 		ret = 0;
75 	}
76 	if (ret)
77 		return ret;
78 
79 	return 0;
80 }
81 
82 #ifdef CONFIG_OF_CONTROL
83 int dm_scan_fdt_node(struct udevice *parent, const void *blob, int offset,
84 		     bool pre_reloc_only)
85 {
86 	int ret = 0, err;
87 
88 	for (offset = fdt_first_subnode(blob, offset);
89 	     offset > 0;
90 	     offset = fdt_next_subnode(blob, offset)) {
91 		if (pre_reloc_only &&
92 		    !fdt_getprop(blob, offset, "u-boot,dm-pre-reloc", NULL))
93 			continue;
94 		err = lists_bind_fdt(parent, blob, offset, NULL);
95 		if (err && !ret)
96 			ret = err;
97 	}
98 
99 	if (ret)
100 		dm_warn("Some drivers failed to bind\n");
101 
102 	return ret;
103 }
104 
105 int dm_scan_fdt(const void *blob, bool pre_reloc_only)
106 {
107 	return dm_scan_fdt_node(gd->dm_root, blob, 0, pre_reloc_only);
108 }
109 #endif
110 
111 __weak int dm_scan_other(bool pre_reloc_only)
112 {
113 	return 0;
114 }
115 
116 int dm_init_and_scan(bool pre_reloc_only)
117 {
118 	int ret;
119 
120 	ret = dm_init();
121 	if (ret) {
122 		debug("dm_init() failed: %d\n", ret);
123 		return ret;
124 	}
125 	ret = dm_scan_platdata(pre_reloc_only);
126 	if (ret) {
127 		debug("dm_scan_platdata() failed: %d\n", ret);
128 		return ret;
129 	}
130 #ifdef CONFIG_OF_CONTROL
131 	ret = dm_scan_fdt(gd->fdt_blob, pre_reloc_only);
132 	if (ret) {
133 		debug("dm_scan_fdt() failed: %d\n", ret);
134 		return ret;
135 	}
136 #endif
137 	ret = dm_scan_other(pre_reloc_only);
138 	if (ret)
139 		return ret;
140 
141 	return 0;
142 }
143 
144 /* This is the root driver - all drivers are children of this */
145 U_BOOT_DRIVER(root_driver) = {
146 	.name	= "root_driver",
147 	.id	= UCLASS_ROOT,
148 };
149 
150 /* This is the root uclass */
151 UCLASS_DRIVER(root) = {
152 	.name	= "root",
153 	.id	= UCLASS_ROOT,
154 };
155