Split build of kernel headers and kernel image into two source trees.
Kernel headers are built in $(TOOL_BUILD_DIR)
Kernel build is in $(PROJECT_BUILD_DIR)
Make sure that kernel patches are applied to the kernel tree in
$(PROJECT_BUILD_DIR)
Add board specific patches, if available.
=========================================================
The purpose of the BSP patch is to allow building
several boards inside the same buildroot tree.
For this to work, each board has to have its
own "$(TARGET_DIR)" and all *configurable* packages
must be rebuilt for each board.
They are now built in the "$(PROJECT_BUILD_DIR)"
All non configurable packages can and should still
be built in the "$(BUILD_DIR)".
If a package is built for one board, then when
you build for a second board of the same architecture
the build becomes a simple copy of the resulting
binaries.
-----
Define BR2_PROJECT which will be used as the selector
between different boards. Note that BR2_PROJECT allow
you to build multiple root file systems for a single
board, and should not be confused with BR2_BOARD_NAME
which relates to the H/W.
-----
Define PROJECT_BUILD_DIR as "PROJECT_BUILD_DIR/$(PROJECT)"
Define BINARIES_DIR as "binaries/$(PROJECT)"
Define TARGET_DIR as "$(PROJECT_BUILD_DIR)/root"
(some prefix/postfix may apply)
Resulting images are stored in "$(BINARIES_DIR)"
-----
Define a few new environment variables in Makefile
PROJECT: Stripped BR2_PROJECT
DATE: Date of build in YYYY-MM-DD format
HOSTNAME: Stripped BR2_HOSTNAME => /etc/hostname
BANNER: Stripped BR2_BANNER => /etc/issue
Linux and Busybox will be built in $(PROJECT_BUILD_DIR)
More patches will be needed later to ensure all
configurable packages are built in this directory.
Ulf Samuelsson
Bernhard Reutner-Fischer
"Steven J. Hill"