Access to a counter in U-mode is permitted only if the corresponding
bit is set in both mcounteren and scounteren. The current code
ignores mcounteren and checks scounteren only for U-mode access.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Reviewed-by: Palmer Dabbelt <palmer@sifive.com>
Signed-off-by: Palmer Dabbelt <palmer@sifive.com>