X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=doc%2FREADME.fdt-control;h=378b06b108d9e8bb7c834d585f0e1342eb7b0f46;hb=61dc92a29d3028296dc3ff34641c78c402e8c14a;hp=e6d5ed0bb61d664b0c7938c0649262f545d36fad;hpb=b8d7652c81689a69bc6eaa206cf875bbe632831c;p=u-boot

diff --git a/doc/README.fdt-control b/doc/README.fdt-control
index e6d5ed0bb6..378b06b108 100644
--- a/doc/README.fdt-control
+++ b/doc/README.fdt-control
@@ -33,12 +33,6 @@ the features of each board in the device tree file, and have a single
 generic source base.
 
 To enable this feature, add CONFIG_OF_CONTROL to your board config file.
-It is currently supported on ARM, x86 and Microblaze - other architectures
-will need to add code to their arch/xxx/lib/board.c file to locate the
-FDT. Alternatively you can enable generic board support on your board
-(with CONFIG_SYS_GENERIC_BOARD) if this is available (as it is for
-PowerPC). For ARM, Tegra and Exynos5 have device trees available for
-common devices.
 
 
 What is a Flat Device Tree?
@@ -136,6 +130,10 @@ u-boot-dtb.bin which does the above step for you also. If you are using
 CONFIG_SPL_FRAMEWORK, then u-boot.img will be built to include the device
 tree binary.
 
+If CONFIG_OF_BOARD is defined, a board-specific routine will provide the
+device tree at runtime, for example if an earlier bootloader stage creates
+it and passes it to U-Boot.
+
 If CONFIG_OF_HOSTFILE is defined, then it 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.
@@ -156,7 +154,10 @@ address of the fdt binary blob, and will override either of the options.
 Be aware that this environment variable is checked prior to relocation,
 when only the compiled-in environment is available. Therefore it is not
 possible to define this variable in the saved SPI/NAND flash
-environment, for example (it will be ignored).
+environment, for example (it will be ignored). After relocation, this
+variable will be set to the address of the newly relocated fdt blob.
+It is read-only and cannot be changed. It can optionally be used to
+control the boot process of Linux with bootm/bootz commands.
 
 To use this, put something like this in your board header file:
 
@@ -171,22 +172,6 @@ After board configuration is done, fdt supported u-boot can be build in two ways
     $ make DEVICE_TREE=<dts-file-name>
 
 
-Configuration Options
----------------------
-
-A number of run-time configuration options are provided in the /config node
-of the control device tree. You can access these using fdtdec_get_config_int(),
-fdtdec_get_config_bool() and fdtdec_get_config_string().
-
-Available options are:
-
-silent-console
-	If present and non-zero, the console is silenced by default on boot.
-
-no-keyboard
-	Tells U-Boot not to expect an attached keyboard with a VGA console
-
-
 Limitations
 -----------