# # Device Tree Control # config SUPPORT_OF_CONTROL bool config PYLIBFDT bool config DTOC bool select PYLIBFDT config BINMAN bool select DTOC menu "Device Tree Control" depends on SUPPORT_OF_CONTROL config OF_CONTROL bool "Run-time configuration via Device Tree" select OF_LIBFDT select OF_REAL help This feature provides for run-time configuration of U-Boot via a flattened device tree. config OF_REAL bool help Indicates that a real devicetree is available which can be accessed at runtime. This means that dev_read_...() functions can be used to read data from the devicetree for each device. This is true if OF_CONTROL is enabled in U-Boot proper. config OF_BOARD_FIXUP bool "Board-specific manipulation of Device Tree" help In certain circumstances it is necessary to be able to modify U-Boot's device tree (e.g. to delete device from it). This option make the Device Tree writeable and provides a board-specific "board_fix_fdt" callback (called during pre-relocation time), which enables the board initialization to modifiy the Device Tree. The modified copy is subsequently used by U-Boot after relocation. config SPL_OF_CONTROL bool "Enable run-time configuration via Device Tree in SPL" depends on SPL && OF_CONTROL select SPL_OF_LIBFDT if !SPL_OF_PLATDATA select SPL_OF_REAL if !SPL_OF_PLATDATA help Some boards use device tree in U-Boot but only have 4KB of SRAM which is not enough to support device tree. Disable this option to allow such boards to be supported by U-Boot SPL. config TPL_OF_CONTROL bool "Enable run-time configuration via Device Tree in TPL" depends on TPL && OF_CONTROL select TPL_OF_LIBFDT if !TPL_OF_PLATDATA select TPL_OF_REAL if !TPL_OF_PLATDATA 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 TPL. config VPL_OF_CONTROL bool "Enable run-time configuration via Device Tree in VPL" depends on VPL && OF_CONTROL default y if 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 VPL. config OF_LIVE bool "Enable use of a live tree" depends on DM && OF_CONTROL help Normally U-Boot uses a flat device tree which saves space and avoids the need to unpack the tree before use. However a flat tree does not support modification from within U-Boot since it can invalidate driver-model device tree offsets. This option enables a live tree which is available after relocation, and can be adjusted as needed. config OF_UPSTREAM bool "Enable use of devicetree imported from Linux kernel release" help Traditionally, U-Boot platforms used to have their custom devicetree files or copy devicetree files from Linux kernel which are hard to maintain and can usually get out-of-sync from Linux kernel. This option enables platforms to migrate to devicetree-rebasing repo where a regular sync will be maintained every major Linux kernel release cycle. However, platforms can still have some custom u-boot specific bits maintained as part of *-u-boot.dtsi files. Note: This option should be set in Kconfig, for the SoC as a whole. However, newer boards whose devicetree source files haven't landed in the dts/upstream subtree, they can override this option to have the DT build from existing U-Boot tree location instead. choice prompt "Provider of DTB for DT control" depends on OF_CONTROL config OF_SEPARATE bool "Separate DTB for DT control" 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. endchoice config OF_BOARD bool "Provided by the board (e.g a previous loader) at runtime" default y if SANDBOX || OF_HAS_PRIOR_STAGE help If this option is enabled, the device tree is provided at runtime by a custom function called board_fdt_blob_setup(). The board must implement this function if it wishes to provide special behaviour. With this option, the device tree build by U-Boot may be overridden or ignored. See OF_HAS_PRIOR_STAGE. Note: Boards which use this to handle a device tree passed from an earlier stage should enable OF_HAS_PRIOR_STAGE. config OF_HAS_PRIOR_STAGE bool depends on !BLOBLIST help Indicates that a prior stage of the firmware (before U-Boot proper) makes use of device tree and this board normally boots with that prior stage, that provides a devicetree to U-Boot. This means that the device tree built in U-Boot should not be packaged in the firmware image. Instead, the prior stage's device tree should be so packaged. At runtime, the prior stage reads this, does any necessary fix-ups, then passes it to U-Boot. See OF_BOARD. This option does not preclude using the U-Boot device tree, e.g. for development purposes, but it is not recommended, and likely will not even work, for production systems. Note: This option must be set in Kconfig and cannot be enabled or disabled in the board's defconfig file. config OF_OMIT_DTB bool "Omit the device tree output when building" default y if OF_HAS_PRIOR_STAGE && !BINMAN help As a special case, avoid writing a device tree file u-boot.dtb when building. Also don't include that file in u-boot.bin This is used for boards which normally provide a devicetree via a runtime mechanism (such as OF_BOARD), to avoid confusion. 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= config DEVICE_TREE_INCLUDES string "Extra .dtsi files to include when building DT control" depends on OF_CONTROL help U-Boot's control .dtb is usually built from an in-tree .dts file, plus (if available) an in-tree U-Boot-specific .dtsi file. This option specifies a space-separated list of extra .dtsi files that will also be used. config OF_LIST string "List of device tree files to include for DT control" if SPL_LOAD_FIT || MULTI_DTB_FIT depends on OF_CONTROL 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, U-Boot or 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 . config OF_OVERLAY_LIST string "List of device tree overlays to include for DT control" depends on SPL_LOAD_FIT_APPLY_OVERLAY help This option specifies a list of device tree overlays to use for DT control. This option can then be used by a FIT generator to include the overlays in the FIT image. choice prompt "OF LIST compression" depends on MULTI_DTB_FIT default MULTI_DTB_FIT_NO_COMPRESSION config MULTI_DTB_FIT_LZO bool "LZO" depends on SYS_MALLOC_F select LZO help Compress the FIT image containing the DTBs available for the SPL using LZO compression. (requires lzop on host). config MULTI_DTB_FIT_GZIP bool "GZIP" depends on SYS_MALLOC_F select GZIP help Compress the FIT image containing the DTBs available for the SPL using GZIP compression. (requires gzip on host) config MULTI_DTB_FIT_NO_COMPRESSION bool "No compression" help Do not compress the FIT image containing the DTBs available for the SPL. Use this options only if LZO is not available and the DTBs are very small. endchoice choice prompt "Location of uncompressed DTBs" depends on (MULTI_DTB_FIT_GZIP || MULTI_DTB_FIT_LZO) default MULTI_DTB_FIT_DYN_ALLOC if SYS_MALLOC_F config MULTI_DTB_FIT_DYN_ALLOC bool "Dynamically allocate the memory" depends on SYS_MALLOC_F config MULTI_DTB_FIT_USER_DEFINED_AREA bool "User-defined location" endchoice config MULTI_DTB_FIT_UNCOMPRESS_SZ hex "Size of memory reserved to uncompress the DTBs" default 0x8000 help This is the size of this area where the DTBs are uncompressed. If this area is dynamically allocated, make sure that SYS_MALLOC_F_LEN is big enough to contain it. config MULTI_DTB_FIT_USER_DEF_ADDR hex "Address of memory where dtbs are uncompressed" depends on MULTI_DTB_FIT_USER_DEFINED_AREA help the FIT image containing the DTBs is uncompressed in an area defined at compilation time. This is the address of this area. It must be aligned on 2-byte boundary. config DTB_RESELECT bool "Support swapping dtbs at a later point in boot" depends on MULTI_DTB_FIT help It is possible during initial boot you may need to use a generic dtb until you can fully determine the board your running on. This config allows boards to implement a function at a later point during boot to switch to the "correct" dtb. config MULTI_DTB_FIT bool "Support embedding several DTBs in a FIT image for u-boot" help This option provides hooks to allow U-Boot to parse an appended FIT image and enable board specific code to then select the correct DTB to be used. Use this if you need to support multiple DTBs but don't use the SPL. config SPL_MULTI_DTB_FIT depends on SPL_LOAD_FIT && SPL_OF_REAL bool "Support embedding several DTBs in a FIT image for the SPL" help This option provides the SPL with the ability to select its own DTB at runtime from an appended FIT image containing several DTBs. This allows using the same SPL binary on multiple platforms. The primary purpose is to handle different versions of the same platform without tweaking the platform code if the differences can be expressed in the DTBs (common examples are: bus capabilities, pad configurations). config SPL_OF_LIST string "List of device tree files to include for DT control in SPL" if SPL_MULTI_DTB_FIT depends on SPL_OF_CONTROL default OF_LIST help This option specifies a list of device tree files to use for DT control in the SPL. These will be packaged into a FIT. At run-time, the 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 . choice prompt "SPL OF LIST compression" depends on SPL_MULTI_DTB_FIT default SPL_MULTI_DTB_FIT_LZO config SPL_MULTI_DTB_FIT_LZO bool "LZO" depends on SYS_MALLOC_F select SPL_LZO help Compress the FIT image containing the DTBs available for the SPL using LZO compression. (requires lzop on host). config SPL_MULTI_DTB_FIT_GZIP bool "GZIP" depends on SYS_MALLOC_F select SPL_GZIP help Compress the FIT image containing the DTBs available for the SPL using GZIP compression. (requires gzip on host) config SPL_MULTI_DTB_FIT_NO_COMPRESSION bool "No compression" help Do not compress the FIT image containing the DTBs available for the SPL. Use this options only if LZO is not available and the DTBs are very small. endchoice choice prompt "Location of uncompressed DTBs" depends on (SPL_MULTI_DTB_FIT_GZIP || SPL_MULTI_DTB_FIT_LZO) default SPL_MULTI_DTB_FIT_DYN_ALLOC if SYS_MALLOC_F config SPL_MULTI_DTB_FIT_DYN_ALLOC bool "Dynamically allocate the memory" depends on SYS_MALLOC_F config SPL_MULTI_DTB_FIT_USER_DEFINED_AREA bool "User-defined location" endchoice config SPL_MULTI_DTB_FIT_UNCOMPRESS_SZ hex "Size of memory reserved to uncompress the DTBs" depends on (SPL_MULTI_DTB_FIT_GZIP || SPL_MULTI_DTB_FIT_LZO) default 0x8000 help This is the size of this area where the DTBs are uncompressed. If this area is dynamically allocated, make sure that SPL_SYS_MALLOC_F_LEN is big enough to contain it. config SPL_MULTI_DTB_FIT_USER_DEF_ADDR hex "Address of memory where dtbs are uncompressed" depends on SPL_MULTI_DTB_FIT_USER_DEFINED_AREA help the FIT image containing the DTBs is uncompressed in an area defined at compilation time. This is the address of this area. It must be aligned on 2-byte boundary. config OF_TAG_MIGRATE bool "Ease migration from old device trees with u-boot,dm- tags" default y help U-Boot moved over to use new tags to mark device tree nodes which need to be processed in SPL, before relocation, etc. Enable this option to detect old tags and handle them. Note: This option will be removed after the 2023.07 release. config OF_SPL_REMOVE_PROPS string "List of device tree properties to drop for SPL" depends on SPL_OF_CONTROL default "interrupt-parent interrupts" if SPL_PINCTRL && SPL_CLK default "clocks clock-names interrupt-parent interrupts" if SPL_PINCTRL default "pinctrl-0 pinctrl-names interrupt-parent interrupts" if SPL_CLK default "pinctrl-0 pinctrl-names clocks clock-names interrupt-parent interrupts" 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 "bootph-all" 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 OF_DTB_PROPS_REMOVE bool "Enable removal of device tree properties" depends on OF_CONTROL help Some boards have restricted amount of storage for U-Boot image. If the generated binary doesn't fit into available image storage, the built-in device tree could probably be cut down by removing some not required device tree properties to reduce the image size. Enable this option and define the properties to be removed in the CONFIG_OF_REMOVE_PROPS list. Do not enable this option if you must pass the built-in DTB directly to the kernel! config OF_REMOVE_PROPS string "List of device tree properties to drop" depends on OF_DTB_PROPS_REMOVE default "interrupt-parent interrupts" if PINCTRL help 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 select DTOC select SPL_OF_PLATDATA_DRIVER_RT if !SPL_OF_PLATDATA_INST 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_DRVINFO() 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_DRVINFO declarations for each node. See of-plat.txt for more information. config SPL_OF_REAL bool "Support a real devicetree in SPL" if SANDBOX depends on SPL_OF_CONTROL select SPL_OF_LIBFDT help Indicates that a real devicetree is available which can be accessed at runtime. This means that dev_read_...() functions can be used to read data from the devicetree for each device. You do not need to enable this option if you have enabled SPL_OF_PLATDATA. if SPL_OF_PLATDATA config SPL_OF_PLATDATA_PARENT bool "Support parent information in devices" default y help Generally it is useful to be able to access the parent of a device with of-platdata. To save space this can be disabled, but in that case dev_get_parent() will always return NULL; config SPL_OF_PLATDATA_INST bool "Declare devices at build time" help Declare devices as udevice instances so that they do not need to be bound when U-Boot starts. This can save time and code space. config SPL_OF_PLATDATA_NO_BIND bool "Don't allow run-time binding of devices" depends on SPL_OF_PLATDATA_INST default y help This removes the ability to bind devices at run time, thus saving some code space in U-Boot. This can be disabled if binding is needed, at the code of some code size increase. config SPL_OF_PLATDATA_RT bool "Use a separate struct for device runtime data" depends on SPL_OF_PLATDATA_INST default y help For systems running SPL from read-only memory it is convenient to separate out the runtime information, so that the devices don't need to be copied before being used. This moves the read-write parts of struct udevice (at present just the flags) into a separate struct, which is allocated at runtime. config SPL_OF_PLATDATA_DRIVER_RT bool help Use a separate struct for driver runtime data. This enables the driver_rt information, used with of-platdata when of-platdata-inst is not used. It allows finding devices by their driver data. endif config TPL_OF_REAL bool help Indicates that a real devicetree is available which can be accessed at runtime. This means that dev_read_...() functions can be used to read data from the devicetree for each device. This is true if TPL_OF_CONTROL is enabled and not TPL_OF_PLATDATA config TPL_OF_PLATDATA bool "Generate platform data for use in TPL" depends on TPL_OF_CONTROL select DTOC select TPL_OF_PLATDATA_DRIVER_RT if !TPL_OF_PLATDATA_INST 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_DRVINFO() 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_DRVINFO declarations for each node. See of-plat.txt for more information. if TPL_OF_PLATDATA config TPL_OF_PLATDATA_PARENT bool "Support parent information in devices" default y help Generally it is useful to be able to access the parent of a device with of-platdata. To save space this can be disabled, but in that case dev_get_parent() will always return NULL; config TPL_OF_PLATDATA_INST bool "Declare devices at build time" help Declare devices as udevice instances so that they do not need to be bound when U-Boot starts. This can save time and code space. config TPL_OF_PLATDATA_NO_BIND bool "Don't allow run-time binding of devices" depends on TPL_OF_PLATDATA_INST default y help This removes the ability to bind devices at run time, thus saving some code space in U-Boot. This can be disabled if binding is needed, at the code of some code size increase. config TPL_OF_PLATDATA_RT bool "Use a separate struct for device runtime data" depends on TPL_OF_PLATDATA_INST default y help For systems running TPL from read-only memory it is convenient to separate out the runtime information, so that the devices don't need to be copied before being used. This moves the read-write parts of struct udevice (at present just the flags) into a separate struct, which is allocated at runtime. config TPL_OF_PLATDATA_DRIVER_RT bool help Use a separate struct for driver runtime data. This enables the driver_rt information, used with of-platdata when of-platdata-inst is not used. It allows finding devices by their driver data. endif config VPL_OF_REAL def_bool y depends on VPL help Indicates that a real devicetree is available which can be accessed at runtime. This means that dev_read_...() functions can be used to read data from the devicetree for each device. This is true if TPL_OF_CONTROL is enabled and not TPL_OF_PLATDATA endmenu