b433d4582d39e6266aaaa60ddd0ece8206afe65e
These cpus only support a simple 16 bit offset from PC, so cannot use it in start.S to compute a large offset. This is okay, because the code that needs it is only for cpus with an MMU, which these dont have.
The Little Kernel Embedded Operating System
The LK kernel is an SMP-aware kernel designed for small systems ported to a variety of platforms and cpu architectures.
It is used in a variety of open source and closed source projects, notably the bootloader for a lot of Android phones of various make.
See https://github.com/littlekernel/lk for the latest version.
For comprehensive documentation, see Index.
High Level Features
- Fully-reentrant multi-threaded preemptive kernel
- Portable to many 32 and 64 bit architectures
- Support for wide variety of embedded and larger platforms
- Powerful modular build system
- Large number of utility components selectable at build time
Supported architectures
- ARM32
- Cortex-M class cores (armv6m - armv8m)
- ARMv7+ Cortex-A class cores
- ARM64
- ARMv8 and ARMv9 cores
- RISC-V 32 and 64bit bit in machine and supervisor mode
- x86-32 and x86-64
- Motorola 68000
- Microblaze
- MIPS
- OpenRISC 1000
- VAX (experimental)
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