dts/Kconfig

   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 OF_BOARD_FIXUP
  18         bool "Board-specific manipulation of Device Tree"
  19         help
  20           In certain circumstances it is necessary to be able to modify
  21           U-Boot's device tree (e.g. to delete device from it). This option
  22           make the Device Tree writeable and provides a board-specific
  23           "board_fix_fdt" callback (called during pre-relocation time), which
  24           enables the board initialization to modifiy the Device Tree. The
  25           modified copy is subsequently used by U-Boot after relocation.
  26
  27 config SPL_OF_CONTROL
  28         bool "Enable run-time configuration via Device Tree in SPL"
  29         depends on SPL && OF_CONTROL
  30         help
  31           Some boards use device tree in U-Boot but only have 4KB of SRAM
  32           which is not enough to support device tree. Enable this option to
  33           allow such boards to be supported by U-Boot SPL.
  34
  35 choice
  36         prompt "Provider of DTB for DT control"
  37         depends on OF_CONTROL
  38
  39 config OF_SEPARATE
  40         bool "Separate DTB for DT control"
  41         depends on !SANDBOX
  42         help
  43           If this option is enabled, the device tree will be built and
  44           placed as a separate u-boot.dtb file alongside the U-Boot image.
  45
  46 config OF_EMBED
  47         bool "Embedded DTB for DT control"
  48         help
  49           If this option is enabled, the device tree will be picked up and
  50           built into the U-Boot image. This is suitable for local debugging
  51           and development only and is not recommended for production devices.
  52           Boards in the mainline U-Boot tree should not use it.
  53
  54 config OF_HOSTFILE
  55         bool "Host filed DTB for DT control"
  56         depends on SANDBOX
  57         help
  58           If this option is enabled, DTB will be read from a file on startup.
  59           This is only useful for Sandbox.  Use the -d flag to U-Boot to
  60           specify the file to read.
  61
  62 endchoice
  63
  64 config DEFAULT_DEVICE_TREE
  65         string "Default Device Tree for DT control"
  66         depends on OF_CONTROL
  67         help
  68           This option specifies the default Device Tree used for DT control.
  69           It can be overridden from the command line:
  70           $ make DEVICE_TREE=<device-tree-name>
  71
  72 config OF_LIST
  73         string "List of device tree files to include for DT control"
  74         depends on SPL_LOAD_FIT
  75         default DEFAULT_DEVICE_TREE
  76         help
  77           This option specifies a list of device tree files to use for DT
  78           control. These will be packaged into a FIT. At run-time, SPL will
  79           select the correct DT to use by examining the hardware (e.g.
  80           reading a board ID value). This is a list of device tree files
  81           (without the directory or .dtb suffix) separated by <space>.
  82
  83 config OF_SPL_REMOVE_PROPS
  84         string "List of device tree properties to drop for SPL"
  85         depends on SPL_OF_CONTROL
  86         default "interrupt-parent" if SPL_PINCTRL && SPL_CLK
  87         default "clocks clock-names interrupt-parent" if SPL_PINCTRL
  88         default "pinctrl-0 pinctrl-names interrupt-parent" if SPL_CLK
  89         default "pinctrl-0 pinctrl-names clocks clock-names interrupt-parent"
  90         help
  91           Since SPL normally runs in a reduced memory space, the device tree
  92           is cut down to only what is needed to load and start U-Boot. Only
  93           nodes marked with the property "u-boot,dm-pre-reloc" will be
  94           included. In addition, some properties are not used by U-Boot and
  95           can be discarded. This option defines the list of properties to
  96           discard.
  97
  98 config SPL_OF_PLATDATA
  99         bool "Generate platform data for use in SPL"
 100         depends on SPL_OF_CONTROL
 101         help
 102           For very constrained SPL environments the overhead of decoding
 103           device tree nodes and converting their contents into platform data
 104           is too large. This overhead includes libfdt code as well as the
 105           device tree contents itself. The latter is fairly compact, but the
 106           former can add 3KB or more to a Thumb 2 Image.
 107
 108           This option enables generation of platform data from the device
 109           tree as C code. This code creates devices using U_BOOT_DEVICE()
 110           declarations. The benefit is that it allows driver code to access
 111           the platform data directly in C structures, avoidin the libfdt
 112           overhead.
 113
 114           This option works by generating C structure declarations for each
 115           compatible string, then adding platform data and U_BOOT_DEVICE
 116           declarations for each node. See README.platdata for more
 117           information.
 118
 119 endmenu