This change adds support for inserting virtual interrupts from HS-mode
into VS-mode using hvien and hvip csrs. This also allows for IRQ filtering
from HS-mode.
Also, the spec doesn't mandate the interrupt to be actually supported
in hardware. Which allows HS-mode to assert virtual interrupts to VS-mode
that have no connection to any real interrupt events.
This is defined as part of the AIA specification [0], "6.3.2 Virtual
interrupts for VS level".
[0]: https://github.com/riscv/riscv-aia/releases/download/1.0/riscv-interrupts-1.0.pdf
Signed-off-by: Rajnesh Kanwal <rkanwal@rivosinc.com>
Reviewed-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
Message-ID: <20231016111736.28721-7-rkanwal@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
40336d5b1d