1 # 2 # Device Tree Control 3 # 4 5 config SUPPORT_OF_CONTROL 6 bool 7 8 menu "Device Tree Control" 9 depends on SUPPORT_OF_CONTROL 10 11 config OF_CONTROL 12 bool "Run-time configuration via Device Tree" 13 help 14 This feature provides for run-time configuration of U-Boot 15 via a flattened device tree. 16 17 config SPL_OF_CONTROL 18 bool "Enable run-time configuration via Device Tree in SPL" 19 depends on SPL && OF_CONTROL 20 help 21 Some boards use device tree in U-Boot but only have 4KB of SRAM 22 which is not enough to support device tree. Enable this option to 23 allow such boards to be supported by U-Boot SPL. 24 25 choice 26 prompt "Provider of DTB for DT control" 27 depends on OF_CONTROL 28 29 config OF_SEPARATE 30 bool "Separate DTB for DT control" 31 depends on !SANDBOX 32 help 33 If this option is enabled, the device tree will be built and 34 placed as a separate u-boot.dtb file alongside the U-Boot image. 35 36 config OF_EMBED 37 bool "Embedded DTB for DT control" 38 help 39 If this option is enabled, the device tree will be picked up and 40 built into the U-Boot image. 41 42 config OF_HOSTFILE 43 bool "Host filed DTB for DT control" 44 depends on SANDBOX 45 help 46 If this option is enabled, DTB will be read from a file on startup. 47 This is only useful for Sandbox. Use the -d flag to U-Boot to 48 specify the file to read. 49 50 endchoice 51 52 config DEFAULT_DEVICE_TREE 53 string "Default Device Tree for DT control" 54 help 55 This option specifies the default Device Tree used for DT control. 56 It can be overridden from the command line: 57 $ make DEVICE_TREE=<device-tree-name> 58 59 config OF_SPL_REMOVE_PROPS 60 string "List of device tree properties to drop for SPL" 61 depends on SPL_OF_CONTROL 62 default "pinctrl-0 pinctrl-names clocks clock-names interrupt-parent" 63 help 64 Since SPL normally runs in a reduced memory space, the device tree 65 is cut down to only what is needed to load and start U-Boot. Only 66 nodes marked with the property "u-boot,dm-pre-reloc" will be 67 included. In addition, some properties are not used by U-Boot and 68 can be discarded. This option defines the list of properties to 69 discard. 70 71 endmenu 72