blob: ba997b1ee3024cb59668f51a41cec42c2a96d5ce [file] [log] [blame]
The bootloader environment consists of a set of libraries that provide
various features and a couple small driver programs that build against
these libraries. The libraries used come from three categories --
generic (containing code useful to any bootloader), architecture
(containing code useful to a specific cpu, system-on-chip, etc), and
board (containing code useful to a single specific device)
For the purpose of this discussion, we will involve the fictional
companies Outstanding Electronics Manufacturing (OEM) and Silicon
Engineering Management, Inc (SEMI). OEM produces the quality Brick
mobile device using SEMI's 65002 ARM-based system-on-chip.
Common bootloader libraries and base architectures:
boot/include/boot headers
boot/libboot libboot.a
boot/libc libboot_c.a
boot/arch_armv6 libboot_arch_armv6.a
Architecture-specific libraries for SEMI 65002 SOC:
partner/semi/boot/include/65002 headers
partner/semi/boot/arch_65002 liboot_arch_65002.a
Device-specific library for OEM Brick phone:
partner/oem/brick/ configuration
partner/oem/brick/boot libboot_board_brick.a
The actual bootloader:
boot/bootloader bootloader
The defines three important build variables:
libboot_board_brick.a \
libboot_arch_65002.a \
Which are used by the bootloader to specify which board and
architecture specific libraries to link against as well as what link
script and init.S to use