xref: /illumos-kvm-cmd/device_tree.c (revision 68396ea9)
1 /*
2  * Functions to help device tree manipulation using libfdt.
3  * 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 #include <stdio.h>
15 #include <sys/types.h>
16 #include <sys/stat.h>
17 #include <fcntl.h>
18 #include <unistd.h>
19 #include <stdlib.h>
20 
21 #include "config.h"
22 #include "qemu-common.h"
23 #include "sysemu.h"
24 #include "device_tree.h"
25 #include "hw/loader.h"
26 
27 #include <libfdt.h>
28 
load_device_tree(const char * filename_path,int * sizep)29 void *load_device_tree(const char *filename_path, int *sizep)
30 {
31     int dt_size;
32     int dt_file_load_size;
33     int ret;
34     void *fdt = NULL;
35 
36     *sizep = 0;
37     dt_size = get_image_size(filename_path);
38     if (dt_size < 0) {
39         printf("Unable to get size of device tree file '%s'\n",
40             filename_path);
41         goto fail;
42     }
43 
44     /* Expand to 2x size to give enough room for manipulation.  */
45     dt_size *= 2;
46     /* First allocate space in qemu for device tree */
47     fdt = qemu_mallocz(dt_size);
48 
49     dt_file_load_size = load_image(filename_path, fdt);
50     if (dt_file_load_size < 0) {
51         printf("Unable to open device tree file '%s'\n",
52                filename_path);
53         goto fail;
54     }
55 
56     ret = fdt_open_into(fdt, fdt, dt_size);
57     if (ret) {
58         printf("Unable to copy device tree in memory\n");
59         goto fail;
60     }
61 
62     /* Check sanity of device tree */
63     if (fdt_check_header(fdt)) {
64         printf ("Device tree file loaded into memory is invalid: %s\n",
65             filename_path);
66         goto fail;
67     }
68     *sizep = dt_size;
69     return fdt;
70 
71 fail:
72     qemu_free(fdt);
73     return NULL;
74 }
75 
qemu_devtree_setprop(void * fdt,const char * node_path,const char * property,uint32_t * val_array,int size)76 int qemu_devtree_setprop(void *fdt, const char *node_path,
77                          const char *property, uint32_t *val_array, int size)
78 {
79     int offset;
80 
81     offset = fdt_path_offset(fdt, node_path);
82     if (offset < 0)
83         return offset;
84 
85     return fdt_setprop(fdt, offset, property, val_array, size);
86 }
87 
qemu_devtree_setprop_cell(void * fdt,const char * node_path,const char * property,uint32_t val)88 int qemu_devtree_setprop_cell(void *fdt, const char *node_path,
89                               const char *property, uint32_t val)
90 {
91     int offset;
92 
93     offset = fdt_path_offset(fdt, node_path);
94     if (offset < 0)
95         return offset;
96 
97     return fdt_setprop_cell(fdt, offset, property, val);
98 }
99 
qemu_devtree_setprop_string(void * fdt,const char * node_path,const char * property,const char * string)100 int qemu_devtree_setprop_string(void *fdt, const char *node_path,
101                                 const char *property, const char *string)
102 {
103     int offset;
104 
105     offset = fdt_path_offset(fdt, node_path);
106     if (offset < 0)
107         return offset;
108 
109     return fdt_setprop_string(fdt, offset, property, string);
110 }
111