rBoot

The x86_64 and aarch64 UEFI bootloader for rCore / zCore OS.

Build

cargo build --release --target x86_64-unknown-uefi
cargo build --release --target aarch64-unknown-uefi

The EFI binaries are located under target/<target>/release/rboot.efi.

Example

See example-kernel/ for a minimal bare-metal kernel that boots via rboot and prints to serial.

Run example-kernel/test.sh to build and test in QEMU. Run example-kernel/test-aarch64.sh for the equivalent aarch64 QEMU test.

Configuration

Edit rboot.conf to configure the bootloader. See example-kernel/rboot.conf for a working example. Available options:

• kernel_path - path to the kernel ELF binary
• kernel_stack_address - virtual address for the kernel stack
• kernel_stack_size - kernel stack size in 4KiB pages
• physical_memory_offset - virtual address offset for physical memory mapping
• resolution - graphic output resolution (e.g. 1024x768)
• initramfs - path to the initial ramdisk image
• cmdline - kernel command line
• uart_base - UART physical address passed to an aarch64 kernel
• gic_base - GIC distributor physical address passed to an aarch64 kernel
• firmware_type - platform identifier passed to an aarch64 kernel

On aarch64, physical_memory_offset must be aligned to 512 GiB. The temporary boot page tables derive RAM and device memory attributes from the UEFI memory map before transferring control to the kernel.