xref: /openbmc/u-boot/drivers/core/root.c (revision 93322749)
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 
77 	return ret;
78 }
79 
80 #ifdef CONFIG_OF_CONTROL
81 int dm_scan_fdt_node(struct udevice *parent, const void *blob, int offset,
82 		     bool pre_reloc_only)
83 {
84 	int ret = 0, err;
85 
86 	for (offset = fdt_first_subnode(blob, offset);
87 	     offset > 0;
88 	     offset = fdt_next_subnode(blob, offset)) {
89 		if (pre_reloc_only &&
90 		    !fdt_getprop(blob, offset, "u-boot,dm-pre-reloc", NULL))
91 			continue;
92 		err = lists_bind_fdt(parent, blob, offset, NULL);
93 		if (err && !ret)
94 			ret = err;
95 	}
96 
97 	if (ret)
98 		dm_warn("Some drivers failed to bind\n");
99 
100 	return ret;
101 }
102 
103 int dm_scan_fdt(const void *blob, bool pre_reloc_only)
104 {
105 	return dm_scan_fdt_node(gd->dm_root, blob, 0, pre_reloc_only);
106 }
107 #endif
108 
109 __weak int dm_scan_other(bool pre_reloc_only)
110 {
111 	return 0;
112 }
113 
114 int dm_init_and_scan(bool pre_reloc_only)
115 {
116 	int ret;
117 
118 	ret = dm_init();
119 	if (ret) {
120 		debug("dm_init() failed: %d\n", ret);
121 		return ret;
122 	}
123 	ret = dm_scan_platdata(pre_reloc_only);
124 	if (ret) {
125 		debug("dm_scan_platdata() failed: %d\n", ret);
126 		return ret;
127 	}
128 #ifdef CONFIG_OF_CONTROL
129 	ret = dm_scan_fdt(gd->fdt_blob, pre_reloc_only);
130 	if (ret) {
131 		debug("dm_scan_fdt() failed: %d\n", ret);
132 		return ret;
133 	}
134 #endif
135 	ret = dm_scan_other(pre_reloc_only);
136 	if (ret)
137 		return ret;
138 
139 	return 0;
140 }
141 
142 /* This is the root driver - all drivers are children of this */
143 U_BOOT_DRIVER(root_driver) = {
144 	.name	= "root_driver",
145 	.id	= UCLASS_ROOT,
146 };
147 
148 /* This is the root uclass */
149 UCLASS_DRIVER(root) = {
150 	.name	= "root",
151 	.id	= UCLASS_ROOT,
152 };
153