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 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. This is suitable for local debugging
  41           and development only and is not recommended for production devices.
  42           Boards in the mainline U-Boot tree should not use it.
  43
  44 config OF_HOSTFILE
  45         bool "Host filed DTB for DT control"
  46         depends on SANDBOX
  47         help
  48           If this option is enabled, DTB will be read from a file on startup.
  49           This is only useful for Sandbox.  Use the -d flag to U-Boot to
  50           specify the file to read.
  51
  52 endchoice
  53
  54 config DEFAULT_DEVICE_TREE
  55         string "Default Device Tree for DT control"
  56         depends on OF_CONTROL
  57         help
  58           This option specifies the default Device Tree used for DT control.
  59           It can be overridden from the command line:
  60           $ make DEVICE_TREE=<device-tree-name>
  61
  62 config OF_LIST
  63         string "List of device tree files to include for DT control"
  64         depends on SPL_LOAD_FIT
  65         default DEFAULT_DEVICE_TREE
  66         help
  67           This option specifies a list of device tree files to use for DT
  68           control. These will be packaged into a FIT. At run-time, SPL will
  69           select the correct DT to use by examining the hardware (e.g.
  70           reading a board ID value). This is a list of device tree files
  71           (without the directory or .dtb suffix) separated by <space>.
  72
  73 config OF_SPL_REMOVE_PROPS
  74         string "List of device tree properties to drop for SPL"
  75         depends on SPL_OF_CONTROL
  76         default "interrupt-parent" if SPL_PINCTRL_FULL && SPL_CLK
  77         default "clocks clock-names interrupt-parent" if SPL_PINCTRL_FULL
  78         default "pinctrl-0 pinctrl-names interrupt-parent" if SPL_CLK
  79         default "pinctrl-0 pinctrl-names clocks clock-names interrupt-parent"
  80         help
  81           Since SPL normally runs in a reduced memory space, the device tree
  82           is cut down to only what is needed to load and start U-Boot. Only
  83           nodes marked with the property "u-boot,dm-pre-reloc" will be
  84           included. In addition, some properties are not used by U-Boot and
  85           can be discarded. This option defines the list of properties to
  86           discard.
  87
  88 config SPL_OF_PLATDATA
  89         bool "Generate platform data for use in SPL"
  90         depends on SPL_OF_CONTROL
  91         help
  92           For very constrained SPL environments the overhead of decoding
  93           device tree nodes and converting their contents into platform data
  94           is too large. This overhead includes libfdt code as well as the
  95           device tree contents itself. The latter is fairly compact, but the
  96           former can add 3KB or more to a Thumb 2 Image.
  97
  98           This option enables generation of platform data from the device
  99           tree as C code. This code creates devices using U_BOOT_DEVICE()
 100           declarations. The benefit is that it allows driver code to access
 101           the platform data directly in C structures, avoidin the libfdt
 102           overhead.
 103
 104           This option works by generating C structure declarations for each
 105           compatible string, then adding platform data and U_BOOT_DEVICE
 106           declarations for each node. See README.platdata for more
 107           information.
 108
 109 endmenu