xref: /optee_os/core/include/kernel/dt.h (revision 1bb929836182ecb96d2d9d268daa807c67596396)
1 /* SPDX-License-Identifier: BSD-2-Clause */
2 /*
3  * Copyright (c) 2016, Linaro Limited
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright notice,
10  * this list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright notice,
13  * this list of conditions and the following disclaimer in the documentation
14  * and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
20  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #ifndef KERNEL_DT_H
30 #define KERNEL_DT_H
31 
32 #include <compiler.h>
33 #include <stdint.h>
34 #include <types_ext.h>
35 #include <util.h>
36 
37 /*
38  * Bitfield to reflect status and secure-status values ("okay", "disabled"
39  * or not present)
40  */
41 #define DT_STATUS_DISABLED 0
42 #define DT_STATUS_OK_NSEC  BIT(0)
43 #define DT_STATUS_OK_SEC   BIT(1)
44 
45 #if defined(CFG_DT)
46 
47 /*
48  * DT-aware drivers
49  */
50 
51 struct dt_device_match {
52 	const char *compatible;
53 };
54 
55 struct dt_driver {
56 	const char *name;
57 	const struct dt_device_match *match_table; /* null-terminated */
58 	const void *driver;
59 };
60 
61 #define __dt_driver __section(".rodata.dtdrv")
62 
63 /*
64  * Find a driver that is suitable for the given DT node, that is, with
65  * a matching "compatible" property.
66  *
67  * @fdt: pointer to the device tree
68  * @offs: node offset
69  */
70 const struct dt_driver *dt_find_compatible_driver(const void *fdt, int offs);
71 
72 const struct dt_driver *__dt_driver_start(void);
73 
74 const struct dt_driver *__dt_driver_end(void);
75 
76 /*
77  * Map a device into secure or non-secure memory and return the base VA and
78  * the mapping size. The mapping is done with type MEM_AREA_IO_SEC or
79  * MEM_AREA_IO_NSEC, depending on the device status.
80  * If the mapping already exists, the function simply returns the @vbase and
81  * @size information.
82  *
83  * @offs is the offset of the node that describes the device in @fdt.
84  * @base receives the base virtual address corresponding to the base physical
85  * address of the "reg" property
86  * @size receives the size of the mapping
87  *
88  * Returns 0 on success or -1 in case of error.
89  */
90 int dt_map_dev(const void *fdt, int offs, vaddr_t *base, size_t *size);
91 
92 /*
93  * Check whether the node at @offs contains the property with propname or not.
94  *
95  * @offs is the offset of the node that describes the device in @fdt.
96  * @propname is the property that need to check
97  *
98  * Returns true on success or false if no propname.
99  */
100 bool dt_have_prop(const void *fdt, int offs, const char *propname);
101 
102 /*
103  * FDT manipulation functions, not provided by <libfdt.h>
104  */
105 
106 /*
107  * Return the base address for the "reg" property of the specified node or
108  * (paddr_t)-1 in case of error
109  */
110 paddr_t _fdt_reg_base_address(const void *fdt, int offs);
111 
112 /*
113  * Return the reg size for the reg property of the specified node or -1 in case
114  * of error
115  */
116 ssize_t _fdt_reg_size(const void *fdt, int offs);
117 
118 /*
119  * Read the status and secure-status properties into a bitfield.
120  * @status is set to DT_STATUS_DISABLED or a combination of DT_STATUS_OK_NSEC
121  * and DT_STATUS_OK_SEC
122  * Returns 0 on success or -1 in case of error.
123  */
124 int _fdt_get_status(const void *fdt, int offs);
125 
126 #else /* !CFG_DT */
127 
128 static inline const struct dt_driver *__dt_driver_start(void)
129 {
130 	return NULL;
131 }
132 
133 static inline const struct dt_driver *__dt_driver_end(void)
134 {
135 	return NULL;
136 }
137 
138 static inline const struct dt_driver *dt_find_compatible_driver(
139 					const void *fdt __unused,
140 					int offs __unused)
141 {
142 	return NULL;
143 }
144 
145 static inline int dt_map_dev(const void *fdt __unused, int offs __unused,
146 			     vaddr_t *vbase __unused, size_t *size __unused)
147 {
148 	return -1;
149 }
150 
151 static inline paddr_t _fdt_reg_base_address(const void *fdt __unused,
152 					    int offs __unused)
153 {
154 	return (paddr_t)-1;
155 }
156 
157 static inline ssize_t _fdt_reg_size(const void *fdt __unused,
158 				    int offs __unused)
159 {
160 	return -1;
161 }
162 
163 static inline int _fdt_get_status(const void *fdt __unused, int offs __unused)
164 {
165 	return -1;
166 }
167 
168 #endif /* !CFG_DT */
169 
170 #define for_each_dt_driver(drv) \
171 	for (drv = __dt_driver_start(); drv < __dt_driver_end(); drv++)
172 
173 #endif /* KERNEL_DT_H */
174