Instead of relying on atomics to access the MIP register let's update
our helper function to instead just lock the IO mutex thread before
writing. This follows the same concept as used in PPC for handling
interrupts
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Palmer Dabbelt <palmer@dabbelt.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com>