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 sjg@chromium.org --- Changes in v3: - Add fdtcontroladdr environment variable
README | 4 ++++ arch/arm/lib/board.c | 30 +++++++++++++++++++++++------- doc/README.fdt-control | 12 ++++++++++++ 3 files changed, 39 insertions(+), 7 deletions(-)
diff --git a/README b/README index fc1cd00..3b1faf9 100644 --- a/README +++ b/README @@ -3493,6 +3493,10 @@ 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 b0f3162..f26d77a 100644 --- a/arch/arm/lib/board.c +++ b/arch/arm/lib/board.c @@ -116,18 +116,31 @@ void blue_led_off(void) __attribute__((weak, alias("__blue_led_off"))); * but let's get it working (again) first... */
+/** + * Decode the value of an environment variable and return it. + * + * @param name Name of environemnt variable + * @param base Number base to use (normally 10, or 16 for hex) + * @param default_val Default value to return if the variable is not + * found + * @return the decoded value, or default_val if not found + */ +static int getenv_int(const char *name, int base, int default_val) +{ + char tmp[64]; /* long enough for environment variables */ + int i = getenv_f(name, tmp, sizeof(tmp)); + + return (i > 0) + ? (int) simple_strtoul(tmp, NULL, base) + : default_val; +} + #if defined(CONFIG_ARM_DCC) && !defined(CONFIG_BAUDRATE) #define CONFIG_BAUDRATE 115200 #endif static int init_baudrate(void) { - char tmp[64]; /* long enough for environment variables */ - int i = getenv_f("baudrate", tmp, sizeof(tmp)); - - gd->baudrate = (i > 0) - ? (int) simple_strtoul(tmp, NULL, 10) - : CONFIG_BAUDRATE; - + gd->baudrate = getenv_int("baudrate", 10, CONFIG_BAUDRATE); return (0); }
@@ -298,6 +311,9 @@ 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_int("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 -----------