1# 2# Device Tree Control 3# 4 5config SUPPORT_OF_CONTROL 6 bool 7 8config DTC 9 bool 10 11config PYLIBFDT 12 bool 13 14config DTOC 15 bool 16 select PYLIBFDT 17 18config BINMAN 19 bool 20 select DTOC 21 22menu "Device Tree Control" 23 depends on SUPPORT_OF_CONTROL 24 25config OF_CONTROL 26 bool "Run-time configuration via Device Tree" 27 select DTC 28 help 29 This feature provides for run-time configuration of U-Boot 30 via a flattened device tree. 31 32config OF_BOARD_FIXUP 33 bool "Board-specific manipulation of Device Tree" 34 help 35 In certain circumstances it is necessary to be able to modify 36 U-Boot's device tree (e.g. to delete device from it). This option 37 make the Device Tree writeable and provides a board-specific 38 "board_fix_fdt" callback (called during pre-relocation time), which 39 enables the board initialization to modifiy the Device Tree. The 40 modified copy is subsequently used by U-Boot after relocation. 41 42config SPL_OF_CONTROL 43 bool "Enable run-time configuration via Device Tree in SPL" 44 depends on SPL && OF_CONTROL 45 help 46 Some boards use device tree in U-Boot but only have 4KB of SRAM 47 which is not enough to support device tree. Enable this option to 48 allow such boards to be supported by U-Boot SPL. 49 50config SPL_DTB_MINIMUM 51 bool "Provide a minimum SPL DTB " 52 depends on SPL_OF_CONTROL 53 default n 54 help 55 Some boards need a SPL DTB as smaller as possible to save dm scan 56 time and space. It provides a SPL DTB only include the node with 57 property "u-boot,dm-spl". The property "u-boot,pre-reloc" doesn't 58 work any more. 59 60config TPL_OF_CONTROL 61 bool "Enable run-time configuration via Device Tree in TPL" 62 depends on TPL && OF_CONTROL 63 help 64 Some boards use device tree in U-Boot but only have 4KB of SRAM 65 which is not enough to support device tree. Enable this option to 66 allow such boards to be supported by U-Boot TPL. 67 68config OF_LIVE 69 bool "Enable use of a live tree" 70 depends on OF_CONTROL 71 help 72 Normally U-Boot uses a flat device tree which saves space and 73 avoids the need to unpack the tree before use. However a flat 74 tree does not support modifcation from within U-Boot since it 75 can invalidate driver-model device tree offsets. This option 76 enables a live tree which is available after relocation, 77 and can be adjusted as needed. 78 79choice 80 prompt "Provider of DTB for DT control" 81 depends on OF_CONTROL 82 83config OF_SEPARATE 84 bool "Separate DTB for DT control" 85 depends on !SANDBOX 86 help 87 If this option is enabled, the device tree will be built and 88 placed as a separate u-boot.dtb file alongside the U-Boot image. 89 90config OF_EMBED 91 bool "Embedded DTB for DT control" 92 help 93 If this option is enabled, the device tree will be picked up and 94 built into the U-Boot image. This is suitable for local debugging 95 and development only and is not recommended for production devices. 96 Boards in the mainline U-Boot tree should not use it. 97 98config OF_BOARD 99 bool "Provided by the board at runtime" 100 depends on !SANDBOX 101 help 102 If this option is enabled, the device tree will be provided by 103 the board at runtime if the board supports it, instead of being 104 bundled with the image. 105 106config OF_HOSTFILE 107 bool "Host filed DTB for DT control" 108 depends on SANDBOX 109 help 110 If this option is enabled, DTB will be read from a file on startup. 111 This is only useful for Sandbox. Use the -d flag to U-Boot to 112 specify the file to read. 113 114endchoice 115 116config DEFAULT_DEVICE_TREE 117 string "Default Device Tree for DT control" 118 depends on OF_CONTROL 119 help 120 This option specifies the default Device Tree used for DT control. 121 It can be overridden from the command line: 122 $ make DEVICE_TREE=<device-tree-name> 123 124config OF_LIST 125 string "List of device tree files to include for DT control" 126 depends on SPL_LOAD_FIT || MULTI_DTB_FIT 127 default DEFAULT_DEVICE_TREE 128 help 129 This option specifies a list of device tree files to use for DT 130 control. These will be packaged into a FIT. At run-time, U-boot 131 or SPL will select the correct DT to use by examining the 132 hardware (e.g. reading a board ID value). This is a list of 133 device tree files (without the directory or .dtb suffix) 134 separated by <space>. 135 136 137config DTB_RESELECT 138 bool "Support swapping dtbs at a later point in boot" 139 depends on MULTI_DTB_FIT 140 help 141 It is possible during initial boot you may need to use a generic 142 dtb until you can fully determine the board your running on. This 143 config allows boards to implement a function at a later point 144 during boot to switch to the "correct" dtb. 145 146config MULTI_DTB_FIT 147 bool "Support embedding several DTBs in a FIT image for u-boot" 148 help 149 This option provides hooks to allow U-boot to parse an 150 appended FIT image and enable board specific code to then select 151 the correct DTB to be used. Use this if you need to support 152 multiple DTBs but don't use the SPL. 153 154 155config SPL_MULTI_DTB_FIT 156 depends on SPL_LOAD_FIT && SPL_OF_CONTROL && !SPL_OF_PLATDATA 157 bool "Support embedding several DTBs in a FIT image for the SPL" 158 help 159 This option provides the SPL with the ability to select its own 160 DTB at runtime from an appended FIT image containing several DTBs. 161 This allows using the same SPL binary on multiple platforms. 162 The primary purpose is to handle different versions of 163 the same platform without tweaking the platform code if the 164 differences can be expressed in the DTBs (common examples are: bus 165 capabilities, pad configurations). 166 167config SPL_OF_LIST 168 string "List of device tree files to include for DT control in SPL" 169 depends on SPL_MULTI_DTB_FIT 170 default OF_LIST 171 help 172 This option specifies a list of device tree files to use for DT 173 control in the SPL. These will be packaged into a FIT. At run-time, 174 the SPL will select the correct DT to use by examining the 175 hardware (e.g. reading a board ID value). This is a list of 176 device tree files (without the directory or .dtb suffix) 177 separated by <space>. 178 179choice 180 prompt "SPL OF LIST compression" 181 depends on SPL_MULTI_DTB_FIT 182 default SPL_MULTI_DTB_FIT_LZO 183 184config SPL_MULTI_DTB_FIT_LZO 185 bool "LZO" 186 depends on SYS_MALLOC_F 187 select SPL_LZO 188 help 189 Compress the FIT image containing the DTBs available for the SPL 190 using LZO compression. (requires lzop on host). 191 192config SPL_MULTI_DTB_FIT_GZIP 193 bool "GZIP" 194 depends on SYS_MALLOC_F 195 select SPL_GZIP 196 help 197 Compress the FIT image containing the DTBs available for the SPL 198 using GZIP compression. (requires gzip on host) 199 200config SPL_MULTI_DTB_FIT_NO_COMPRESSION 201 bool "No compression" 202 help 203 Do not compress the FIT image containing the DTBs available for the SPL. 204 Use this options only if LZO is not available and the DTBs are very small. 205endchoice 206 207choice 208 prompt "Location of uncompressed DTBs " 209 depends on (SPL_MULTI_DTB_FIT_GZIP || SPL_MULTI_DTB_FIT_LZO) 210 default SPL_MULTI_DTB_FIT_DYN_ALLOC if SYS_MALLOC_F 211 212config SPL_MULTI_DTB_FIT_DYN_ALLOC 213 bool "Dynamically allocate the memory" 214 depends on SYS_MALLOC_F 215 216config SPL_MULTI_DTB_FIT_USER_DEFINED_AREA 217 bool "User-defined location" 218endchoice 219 220config SPL_MULTI_DTB_FIT_UNCOMPRESS_SZ 221 hex "Size of memory reserved to uncompress the DTBs" 222 depends on (SPL_MULTI_DTB_FIT_GZIP || SPL_MULTI_DTB_FIT_LZO) 223 default 0x8000 224 help 225 This is the size of this area where the DTBs are uncompressed. 226 If this area is dynamically allocated, make sure that 227 SPL_SYS_MALLOC_F_LEN is big enough to contain it. 228 229config SPL_MULTI_DTB_FIT_USER_DEF_ADDR 230 hex "Address of memory where dtbs are uncompressed" 231 depends on SPL_MULTI_DTB_FIT_USER_DEFINED_AREA 232 help 233 the FIT image containing the DTBs is uncompressed in an area defined 234 at compilation time. This is the address of this area. It must be 235 aligned on 2-byte boundary. 236 237config OF_SPL_REMOVE_PROPS 238 string "List of device tree properties to drop for SPL" 239 default "interrupt-parent" if SPL_PINCTRL && SPL_CLK 240 default "clocks clock-names interrupt-parent" if SPL_PINCTRL 241 default "pinctrl-0 pinctrl-names interrupt-parent" if SPL_CLK 242 default "pinctrl-0 pinctrl-names clocks clock-names interrupt-parent" 243 help 244 Since SPL normally runs in a reduced memory space, the device tree 245 is cut down to only what is needed to load and start U-Boot. Only 246 nodes marked with the property "u-boot,dm-pre-reloc" will be 247 included. In addition, some properties are not used by U-Boot and 248 can be discarded. This option defines the list of properties to 249 discard. 250 251config SPL_OF_PLATDATA 252 bool "Generate platform data for use in SPL" 253 depends on SPL_OF_CONTROL 254 select DTOC 255 help 256 For very constrained SPL environments the overhead of decoding 257 device tree nodes and converting their contents into platform data 258 is too large. This overhead includes libfdt code as well as the 259 device tree contents itself. The latter is fairly compact, but the 260 former can add 3KB or more to a Thumb 2 Image. 261 262 This option enables generation of platform data from the device 263 tree as C code. This code creates devices using U_BOOT_DEVICE() 264 declarations. The benefit is that it allows driver code to access 265 the platform data directly in C structures, avoidin the libfdt 266 overhead. 267 268 This option works by generating C structure declarations for each 269 compatible string, then adding platform data and U_BOOT_DEVICE 270 declarations for each node. See README.platdata for more 271 information. 272 273config TPL_OF_PLATDATA 274 bool "Generate platform data for use in TPL" 275 depends on TPL_OF_CONTROL 276 select DTOC 277 help 278 For very constrained SPL environments the overhead of decoding 279 device tree nodes and converting their contents into platform data 280 is too large. This overhead includes libfdt code as well as the 281 device tree contents itself. The latter is fairly compact, but the 282 former can add 3KB or more to a Thumb 2 Image. 283 284 This option enables generation of platform data from the device 285 tree as C code. This code creates devices using U_BOOT_DEVICE() 286 declarations. The benefit is that it allows driver code to access 287 the platform data directly in C structures, avoidin the libfdt 288 overhead. 289 290 This option works by generating C structure declarations for each 291 compatible string, then adding platform data and U_BOOT_DEVICE 292 declarations for each node. See README.platdata for more 293 information. 294 295endmenu 296 297config MKIMAGE_DTC_PATH 298 string "Path to dtc binary for use within mkimage" 299 default "dtc" 300 help 301 The mkimage host tool will, in order to generate FIT images make 302 calls to the dtc application in order to create the output. In 303 some cases the system dtc may not support all required features 304 and the path to a different version should be given here. 305