u-boot/dts/Kconfig

#
# Device Tree Control
#

config SUPPORT_OF_CONTROL
	bool

config DTC
	bool

menu "Device Tree Control"
	depends on SUPPORT_OF_CONTROL

config OF_CONTROL
	bool "Run-time configuration via Device Tree"
	select DTC
	help
	  This feature provides for run-time configuration of U-Boot
	  via a flattened device tree.

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
	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.

config TPL_OF_CONTROL
	bool "Enable run-time configuration via Device Tree in TPL"
	depends on TPL && 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 TPL.

config OF_LIVE
	bool "Enable use of a live tree"
	depends on 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 modifcation 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.

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_BOARD
	bool "Provided by the board at runtime"
	depends on !SANDBOX
	help
	  If this option is enabled, the device tree will be provided by
	  the board at runtime if the board supports it, instead of being
	  bundled with the image.

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 || MULTI_DTB_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, 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 <space>.


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_CONTROL && !SPL_OF_PLATDATA
	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"
	depends on SPL_MULTI_DTB_FIT
	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 <space>.

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_SPL_REMOVE_PROPS
	string "List of device tree properties to drop for SPL"
	depends on SPL_OF_CONTROL
	default "interrupt-parent" if SPL_PINCTRL && SPL_CLK
	default "clocks clock-names interrupt-parent" if SPL_PINCTRL
	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.

config TPL_OF_PLATDATA
	bool "Generate platform data for use in TPL"
	depends on TPL_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

config MKIMAGE_DTC_PATH
	string "Path to dtc binary for use within mkimage"
	default "dtc"
	help
	  The mkimage host tool will, in order to generate FIT images make
	  calls to the dtc application in order to create the output.  In
	  some cases the system dtc may not support all required features
	  and the path to a different version should be given here.