This patch aims to unify the two currently separated RISC-V 64-bit
architecture ports, 'virt64' and 'c906', into a single generic
'common64' port. The changes include renaming files and updating
includes to use a unified 'interrupt.h' header, as well as making
adjustments to IO and trap handling to be more consistent between the
two architectures.
Changes:
- Renamed 'rt_interrupt.h' to 'interrupt.h' and updated includes accordingly.
- Unified IO register access functions in 'riscv_io.h'.
- Added 'opcode.h' for portable assembly support.
- Updated 'plic.c' and 'plic.h' to handle interrupts in a unified manner.
- Modified 'trap.c' to handle exceptions and interrupts consistently for 'rv64'.
Signed-off-by: Shell <smokewood@qq.com>