xref: /openbmc/qemu/include/sysemu/device_tree.h (revision 750541c4)
1 /*
2  * Header with function prototypes to help device tree manipulation using
3  * libfdt. It also provides functions to read entries from device tree proc
4  * interface.
5  *
6  * Copyright 2008 IBM Corporation.
7  * Authors: Jerone Young <jyoung5@us.ibm.com>
8  *          Hollis Blanchard <hollisb@us.ibm.com>
9  *
10  * This work is licensed under the GNU GPL license version 2 or later.
11  *
12  */
13 
14 #ifndef DEVICE_TREE_H
15 #define DEVICE_TREE_H
16 
17 void *create_device_tree(int *sizep);
18 void *load_device_tree(const char *filename_path, int *sizep);
19 #ifdef CONFIG_LINUX
20 /**
21  * load_device_tree_from_sysfs: reads the device tree information in the
22  * /proc/device-tree directory and return the corresponding binary blob
23  * buffer pointer. Asserts in case of error.
24  */
25 void *load_device_tree_from_sysfs(void);
26 #endif
27 
28 /**
29  * qemu_fdt_node_path: return the paths of nodes matching a given
30  * name and compat string
31  * @fdt: pointer to the dt blob
32  * @name: node name
33  * @compat: compatibility string
34  * @errp: handle to an error object
35  *
36  * returns a newly allocated NULL-terminated array of node paths.
37  * Use g_strfreev() to free it. If one or more nodes were found, the
38  * array contains the path of each node and the last element equals to
39  * NULL. If there is no error but no matching node was found, the
40  * returned array contains a single element equal to NULL. If an error
41  * was encountered when parsing the blob, the function returns NULL
42  */
43 char **qemu_fdt_node_path(void *fdt, const char *name, char *compat,
44                           Error **errp);
45 
46 /**
47  * qemu_fdt_node_unit_path: return the paths of nodes matching a given
48  * node-name, ie. node-name and node-name@unit-address
49  * @fdt: pointer to the dt blob
50  * @name: node name
51  * @errp: handle to an error object
52  *
53  * returns a newly allocated NULL-terminated array of node paths.
54  * Use g_strfreev() to free it. If one or more nodes were found, the
55  * array contains the path of each node and the last element equals to
56  * NULL. If there is no error but no matching node was found, the
57  * returned array contains a single element equal to NULL. If an error
58  * was encountered when parsing the blob, the function returns NULL
59  */
60 char **qemu_fdt_node_unit_path(void *fdt, const char *name, Error **errp);
61 
62 int qemu_fdt_setprop(void *fdt, const char *node_path,
63                      const char *property, const void *val, int size);
64 int qemu_fdt_setprop_cell(void *fdt, const char *node_path,
65                           const char *property, uint32_t val);
66 int qemu_fdt_setprop_u64(void *fdt, const char *node_path,
67                          const char *property, uint64_t val);
68 int qemu_fdt_setprop_string(void *fdt, const char *node_path,
69                             const char *property, const char *string);
70 int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
71                              const char *property,
72                              const char *target_node_path);
73 /**
74  * qemu_fdt_getprop: retrieve the value of a given property
75  * @fdt: pointer to the device tree blob
76  * @node_path: node path
77  * @property: name of the property to find
78  * @lenp: fdt error if any or length of the property on success
79  * @errp: handle to an error object
80  *
81  * returns a pointer to the property on success and NULL on failure
82  */
83 const void *qemu_fdt_getprop(void *fdt, const char *node_path,
84                              const char *property, int *lenp,
85                              Error **errp);
86 /**
87  * qemu_fdt_getprop_cell: retrieve the value of a given 4 byte property
88  * @fdt: pointer to the device tree blob
89  * @node_path: node path
90  * @property: name of the property to find
91  * @lenp: fdt error if any or -EINVAL if the property size is different from
92  *        4 bytes, or 4 (expected length of the property) upon success.
93  * @errp: handle to an error object
94  *
95  * returns the property value on success
96  */
97 uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
98                                const char *property, int *lenp,
99                                Error **errp);
100 uint32_t qemu_fdt_get_phandle(void *fdt, const char *path);
101 uint32_t qemu_fdt_alloc_phandle(void *fdt);
102 int qemu_fdt_nop_node(void *fdt, const char *node_path);
103 int qemu_fdt_add_subnode(void *fdt, const char *name);
104 
105 #define qemu_fdt_setprop_cells(fdt, node_path, property, ...)                 \
106     do {                                                                      \
107         uint32_t qdt_tmp[] = { __VA_ARGS__ };                                 \
108         int i;                                                                \
109                                                                               \
110         for (i = 0; i < ARRAY_SIZE(qdt_tmp); i++) {                           \
111             qdt_tmp[i] = cpu_to_be32(qdt_tmp[i]);                             \
112         }                                                                     \
113         qemu_fdt_setprop(fdt, node_path, property, qdt_tmp,                   \
114                          sizeof(qdt_tmp));                                    \
115     } while (0)
116 
117 void qemu_fdt_dumpdtb(void *fdt, int size);
118 
119 /**
120  * qemu_fdt_setprop_sized_cells_from_array:
121  * @fdt: device tree blob
122  * @node_path: node to set property on
123  * @property: property to set
124  * @numvalues: number of values
125  * @values: array of number-of-cells, value pairs
126  *
127  * Set the specified property on the specified node in the device tree
128  * to be an array of cells. The values of the cells are specified via
129  * the values list, which alternates between "number of cells used by
130  * this value" and "value".
131  * number-of-cells must be either 1 or 2 (other values will result in
132  * an error being returned). If a value is too large to fit in the
133  * number of cells specified for it, an error is returned.
134  *
135  * This function is useful because device tree nodes often have cell arrays
136  * which are either lists of addresses or lists of address,size tuples, but
137  * the number of cells used for each element vary depending on the
138  * #address-cells and #size-cells properties of their parent node.
139  * If you know all your cell elements are one cell wide you can use the
140  * simpler qemu_fdt_setprop_cells(). If you're not setting up the
141  * array programmatically, qemu_fdt_setprop_sized_cells may be more
142  * convenient.
143  *
144  * Return value: 0 on success, <0 on error.
145  */
146 int qemu_fdt_setprop_sized_cells_from_array(void *fdt,
147                                             const char *node_path,
148                                             const char *property,
149                                             int numvalues,
150                                             uint64_t *values);
151 
152 /**
153  * qemu_fdt_setprop_sized_cells:
154  * @fdt: device tree blob
155  * @node_path: node to set property on
156  * @property: property to set
157  * @...: list of number-of-cells, value pairs
158  *
159  * Set the specified property on the specified node in the device tree
160  * to be an array of cells. The values of the cells are specified via
161  * the variable arguments, which alternates between "number of cells
162  * used by this value" and "value".
163  *
164  * This is a convenience wrapper for the function
165  * qemu_fdt_setprop_sized_cells_from_array().
166  *
167  * Return value: 0 on success, <0 on error.
168  */
169 #define qemu_fdt_setprop_sized_cells(fdt, node_path, property, ...)       \
170     ({                                                                    \
171         uint64_t qdt_tmp[] = { __VA_ARGS__ };                             \
172         qemu_fdt_setprop_sized_cells_from_array(fdt, node_path,           \
173                                                 property,                 \
174                                                 ARRAY_SIZE(qdt_tmp) / 2,  \
175                                                 qdt_tmp);                 \
176     })
177 
178 #define FDT_PCI_RANGE_RELOCATABLE          0x80000000
179 #define FDT_PCI_RANGE_PREFETCHABLE         0x40000000
180 #define FDT_PCI_RANGE_ALIASED              0x20000000
181 #define FDT_PCI_RANGE_TYPE_MASK            0x03000000
182 #define FDT_PCI_RANGE_MMIO_64BIT           0x03000000
183 #define FDT_PCI_RANGE_MMIO                 0x02000000
184 #define FDT_PCI_RANGE_IOPORT               0x01000000
185 #define FDT_PCI_RANGE_CONFIG               0x00000000
186 
187 #endif /* DEVICE_TREE_H */
188