| # |
| # Device Tree Control |
| # |
| |
| config SUPPORT_OF_CONTROL |
| bool |
| |
| menu "Device Tree Control" |
| depends on SUPPORT_OF_CONTROL |
| |
| config OF_CONTROL |
| bool "Run-time configuration via Device Tree" |
| help |
| This feature provides for run-time configuration of U-Boot |
| via a flattened device tree. |
| |
| config SPL_OF_CONTROL |
| bool "Enable run-time configuration via Device Tree in SPL" |
| depends on SPL && OF_CONTROL |
| help |
| Some boards use device tree in U-Boot but only have 4KB of SRAM |
| which is not enough to support device tree. Enable this option to |
| allow such boards to be supported by U-Boot SPL. |
| |
| choice |
| prompt "Provider of DTB for DT control" |
| depends on OF_CONTROL |
| |
| config OF_SEPARATE |
| bool "Separate DTB for DT control" |
| depends on !SANDBOX |
| help |
| If this option is enabled, the device tree will be built and |
| placed as a separate u-boot.dtb file alongside the U-Boot image. |
| |
| config OF_EMBED |
| bool "Embedded DTB for DT control" |
| help |
| If this option is enabled, the device tree will be picked up and |
| built into the U-Boot image. This is suitable for local debugging |
| and development only and is not recommended for production devices. |
| Boards in the mainline U-Boot tree should not use it. |
| |
| config OF_HOSTFILE |
| bool "Host filed DTB for DT control" |
| depends on SANDBOX |
| help |
| If this option is enabled, DTB will be read from a file on startup. |
| This is only useful for Sandbox. Use the -d flag to U-Boot to |
| specify the file to read. |
| |
| endchoice |
| |
| config DEFAULT_DEVICE_TREE |
| string "Default Device Tree for DT control" |
| depends on OF_CONTROL |
| help |
| This option specifies the default Device Tree used for DT control. |
| It can be overridden from the command line: |
| $ make DEVICE_TREE=<device-tree-name> |
| |
| config OF_LIST |
| string "List of device tree files to include for DT control" |
| depends on SPL_LOAD_FIT |
| default DEFAULT_DEVICE_TREE |
| help |
| This option specifies a list of device tree files to use for DT |
| control. These will be packaged into a FIT. At run-time, SPL will |
| select the correct DT to use by examining the hardware (e.g. |
| reading a board ID value). This is a list of device tree files |
| (without the directory or .dtb suffix) separated by <space>. |
| |
| config OF_SPL_REMOVE_PROPS |
| string "List of device tree properties to drop for SPL" |
| depends on SPL_OF_CONTROL |
| default "interrupt-parent" if SPL_PINCTRL_FULL && SPL_CLK |
| default "clocks clock-names interrupt-parent" if SPL_PINCTRL_FULL |
| default "pinctrl-0 pinctrl-names interrupt-parent" if SPL_CLK |
| default "pinctrl-0 pinctrl-names clocks clock-names interrupt-parent" |
| help |
| Since SPL normally runs in a reduced memory space, the device tree |
| is cut down to only what is needed to load and start U-Boot. Only |
| nodes marked with the property "u-boot,dm-pre-reloc" will be |
| included. In addition, some properties are not used by U-Boot and |
| can be discarded. This option defines the list of properties to |
| discard. |
| |
| config SPL_OF_PLATDATA |
| bool "Generate platform data for use in SPL" |
| depends on SPL_OF_CONTROL |
| help |
| For very constrained SPL environments the overhead of decoding |
| device tree nodes and converting their contents into platform data |
| is too large. This overhead includes libfdt code as well as the |
| device tree contents itself. The latter is fairly compact, but the |
| former can add 3KB or more to a Thumb 2 Image. |
| |
| This option enables generation of platform data from the device |
| tree as C code. This code creates devices using U_BOOT_DEVICE() |
| declarations. The benefit is that it allows driver code to access |
| the platform data directly in C structures, avoidin the libfdt |
| overhead. |
| |
| This option works by generating C structure declarations for each |
| compatible string, then adding platform data and U_BOOT_DEVICE |
| declarations for each node. See README.platdata for more |
| information. |
| |
| endmenu |
