arch: riscv: introduce RISC-V custom CSR common layer
RISC-V allows custom CSR implementation. Some SoCs from different vendors
may share the same core or the same custom CSR definitions and drivers.
This patch introduces 'arch/riscv/custom', which centralizes support
for custom CSRs, allowing code reuse across SoCs that come from different
vendors. Currently supported thess custom CSR:
1. Andes
2. Nuclei
3. OpenHWGroup CVA6
4. OpenISA RI5CY
5. OpenISA Zero-riscy
6. T-Head Xuantie
Signed-off-by: Jimmy Zheng <jimmyzhe@andestech.com>
2 files changed
