1 /* 2 * This file does the necessary interface mapping between the bootwrapper 3 * device tree operations and the interface provided by shared source 4 * files flatdevicetree.[ch]. 5 * 6 * Copyright 2007 David Gibson, IBM Corporation. 7 * 8 * This library is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License as 10 * published by the Free Software Foundation; either version 2 of the 11 * License, or (at your option) any later version. 12 * 13 * This library is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this library; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 21 * 02110-1301 USA 22 */ 23 24 #include <stddef.h> 25 #include <stdio.h> 26 #include <page.h> 27 #include <libfdt.h> 28 #include "ops.h" 29 30 #define DEBUG 0 31 #define BAD_ERROR(err) (((err) < 0) \ 32 && ((err) != -FDT_ERR_NOTFOUND) \ 33 && ((err) != -FDT_ERR_EXISTS)) 34 35 #define check_err(err) \ 36 ({ \ 37 if (BAD_ERROR(err) || ((err < 0) && DEBUG)) \ 38 printf("%s():%d %s\n\r", __func__, __LINE__, \ 39 fdt_strerror(err)); \ 40 if (BAD_ERROR(err)) \ 41 exit(); \ 42 (err < 0) ? -1 : 0; \ 43 }) 44 45 #define offset_devp(off) \ 46 ({ \ 47 int _offset = (off); \ 48 check_err(_offset) ? NULL : (void *)(_offset+1); \ 49 }) 50 51 #define devp_offset_find(devp) (((int)(devp))-1) 52 #define devp_offset(devp) (devp ? ((int)(devp))-1 : 0) 53 54 static void *fdt; 55 static void *buf; /* = NULL */ 56 57 #define EXPAND_GRANULARITY 1024 58 59 static void expand_buf(int minexpand) 60 { 61 int size = fdt_totalsize(fdt); 62 int rc; 63 64 size = _ALIGN(size + minexpand, EXPAND_GRANULARITY); 65 buf = platform_ops.realloc(buf, size); 66 if (!buf) 67 fatal("Couldn't find %d bytes to expand device tree\n\r", size); 68 rc = fdt_open_into(fdt, buf, size); 69 if (rc != 0) 70 fatal("Couldn't expand fdt into new buffer: %s\n\r", 71 fdt_strerror(rc)); 72 73 fdt = buf; 74 } 75 76 static void *fdt_wrapper_finddevice(const char *path) 77 { 78 return offset_devp(fdt_path_offset(fdt, path)); 79 } 80 81 static int fdt_wrapper_getprop(const void *devp, const char *name, 82 void *buf, const int buflen) 83 { 84 const void *p; 85 int len; 86 87 p = fdt_getprop(fdt, devp_offset(devp), name, &len); 88 if (!p) 89 return check_err(len); 90 memcpy(buf, p, min(len, buflen)); 91 return len; 92 } 93 94 static int fdt_wrapper_setprop(const void *devp, const char *name, 95 const void *buf, const int len) 96 { 97 int rc; 98 99 rc = fdt_setprop(fdt, devp_offset(devp), name, buf, len); 100 if (rc == -FDT_ERR_NOSPACE) { 101 expand_buf(len + 16); 102 rc = fdt_setprop(fdt, devp_offset(devp), name, buf, len); 103 } 104 105 return check_err(rc); 106 } 107 108 static void *fdt_wrapper_get_parent(const void *devp) 109 { 110 return offset_devp(fdt_parent_offset(fdt, devp_offset(devp))); 111 } 112 113 static void *fdt_wrapper_create_node(const void *devp, const char *name) 114 { 115 int offset; 116 117 offset = fdt_add_subnode(fdt, devp_offset(devp), name); 118 if (offset == -FDT_ERR_NOSPACE) { 119 expand_buf(strlen(name) + 16); 120 offset = fdt_add_subnode(fdt, devp_offset(devp), name); 121 } 122 123 return offset_devp(offset); 124 } 125 126 static void *fdt_wrapper_find_node_by_prop_value(const void *prev, 127 const char *name, 128 const char *val, 129 int len) 130 { 131 int offset = fdt_node_offset_by_prop_value(fdt, devp_offset_find(prev), 132 name, val, len); 133 return offset_devp(offset); 134 } 135 136 static void *fdt_wrapper_find_node_by_compatible(const void *prev, 137 const char *val) 138 { 139 int offset = fdt_node_offset_by_compatible(fdt, devp_offset_find(prev), 140 val); 141 return offset_devp(offset); 142 } 143 144 static char *fdt_wrapper_get_path(const void *devp, char *buf, int len) 145 { 146 int rc; 147 148 rc = fdt_get_path(fdt, devp_offset(devp), buf, len); 149 if (check_err(rc)) 150 return NULL; 151 return buf; 152 } 153 154 static unsigned long fdt_wrapper_finalize(void) 155 { 156 int rc; 157 158 rc = fdt_pack(fdt); 159 if (rc != 0) 160 fatal("Couldn't pack flat tree: %s\n\r", 161 fdt_strerror(rc)); 162 return (unsigned long)fdt; 163 } 164 165 void fdt_init(void *blob) 166 { 167 int err; 168 169 dt_ops.finddevice = fdt_wrapper_finddevice; 170 dt_ops.getprop = fdt_wrapper_getprop; 171 dt_ops.setprop = fdt_wrapper_setprop; 172 dt_ops.get_parent = fdt_wrapper_get_parent; 173 dt_ops.create_node = fdt_wrapper_create_node; 174 dt_ops.find_node_by_prop_value = fdt_wrapper_find_node_by_prop_value; 175 dt_ops.find_node_by_compatible = fdt_wrapper_find_node_by_compatible; 176 dt_ops.get_path = fdt_wrapper_get_path; 177 dt_ops.finalize = fdt_wrapper_finalize; 178 179 /* Make sure the dt blob is the right version and so forth */ 180 fdt = blob; 181 err = fdt_open_into(fdt, fdt, fdt_totalsize(blob)); 182 if (err == -FDT_ERR_NOSPACE) { 183 int bufsize = fdt_totalsize(fdt) + 4; 184 buf = malloc(bufsize); 185 err = fdt_open_into(fdt, buf, bufsize); 186 } 187 188 if (err != 0) 189 fatal("fdt_init(): %s\n\r", fdt_strerror(err)); 190 191 if (buf) 192 fdt = buf; 193 } 194