From eea63e05d0b7f54e7aa39725015483972c71cb3c Mon Sep 17 00:00:00 2001 From: Simon Glass Date: Mon, 24 Oct 2011 19:15:34 +0000 Subject: [PATCH] fdt: ARM: Add fdtcontroladdr to set device tree address in environment This adds support for a new environment variable called 'fdtcontroladdr'. If defined, the hex address is used as the address of the control fdt for U-Boot. Note: I have not changed CONFIG_PRAM section as I already have an outstanding patch on that. Signed-off-by: Simon Glass --- README | 4 ++++ arch/arm/lib/board.c | 3 +++ doc/README.fdt-control | 12 ++++++++++++ 3 files changed, 19 insertions(+) diff --git a/README b/README index 558f011..a3b62e1 100644 --- a/README +++ b/README @@ -3499,6 +3499,10 @@ List of environment variables (most likely not complete): add the information it needs into it, and the memory must be accessible by the kernel. + fdtcontroladdr- if set this is the address of the control flattened + device tree used by U-Boot when CONFIG_OF_CONTROL is + defined. + i2cfast - (PPC405GP|PPC405EP only) if set to 'y' configures Linux I2C driver for fast mode (400kHZ). This environment variable is used in diff --git a/arch/arm/lib/board.c b/arch/arm/lib/board.c index bd6d4e3..bae2892 100644 --- a/arch/arm/lib/board.c +++ b/arch/arm/lib/board.c @@ -286,6 +286,9 @@ void board_init_f(ulong bootflag) /* FDT is at end of image */ gd->fdt_blob = (void *)(_end_ofs + _TEXT_BASE); #endif + /* Allow the early environment to override the fdt address */ + gd->fdt_blob = (void *)getenv_ulong("fdtcontroladdr", 16, + (uintptr_t)gd->fdt_blob); for (init_fnc_ptr = init_sequence; *init_fnc_ptr; ++init_fnc_ptr) { if ((*init_fnc_ptr)() != 0) { diff --git a/doc/README.fdt-control b/doc/README.fdt-control index 3f8bb5a..85bda03 100644 --- a/doc/README.fdt-control +++ b/doc/README.fdt-control @@ -144,6 +144,18 @@ and then flash image.bin onto your board. You cannot use both of these options at the same time. +If you wish to put the fdt at a different address in memory, you can +define the "fdtcontroladdr" environment variable. This is the hex +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). + +To use this, put something like this in your board header file: + +#define CONFIG_EXTRA_ENV_SETTINGS "fdtcontroladdr=10000\0" + Limitations ----------- -- 2.7.4