When booting U-Boot on board with a locked down first-stage bootloader,
we emulate the Linux boot header. By passing the U-Boot FDT through this
first-stage bootloader and retrieving it afterwards we can pre-populate
the memory nodes and other info like the KASLR address.
Add a function to export the FDT addr so that boards can use it over the
built-in FDT.
Don't check is_addr_accessible() here because we might not yet have a
valid mem_map if it's going to be populated from the FDT, let the board
do their own validation instead.
Reviewed-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Sumit Garg <sumit.garg@linaro.org>
Tested-by: Sumit Garg <sumit.garg@linaro.org> #qcs404
Signed-off-by: Caleb Connolly <caleb.connolly@linaro.org>
This converts 2 usages of this option to the non-SPL form, since there is
no SPL_SAVE_PREV_BL_INITRAMFS_START_ADDR defined in Kconfig
Signed-off-by: Simon Glass <sjg@chromium.org>
This converts 2 usages of this option to the non-SPL form, since there is
no SPL_SAVE_PREV_BL_FDT_ADDR defined in Kconfig
Signed-off-by: Simon Glass <sjg@chromium.org>
When u-boot is used as a chain-loaded bootloader (replacing OS kernel),
previous bootloader leaves data in RAM, that can be reused.
For example, on recent arm linux system, when chainloading u-boot,
there are initramfs and fdt in RAM prepared for OS booting. Initramfs
may be modified to store u-boot's payload, thus providing the ability to
use chainloaded u-boot to boot OS without any storage support.
Two config options added:
- SAVE_PREV_BL_INITRAMFS_START_ADDR
saves initramfs start address to 'prevbl_initrd_start_addr' environment
variable
- SAVE_PREV_BL_FDT_ADDR
saves fdt address to 'prevbl_fdt_addr' environment variable
Signed-off-by: Dzmitry Sankouski <dsankouski@gmail.com>
Cc: Tom Rini <trini@konsulko.com>
