arch/riscv: Configure delegation only if S-mode is supported

On the FU540 the bootblock runs on a core without lesser privilege
modes, so the medeleg/mideleg CSRs are not implemented on that core,
leading to a CPU exception when these CSRs are accessed.

Configure medeleg/mideleg only if the misa register indicates that
S-mode is implemented on the executing RISC-V core.

Change-Id: Idad97e42bac2ff438dd233a5d125f93594505d63
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Reviewed-on: https://review.coreboot.org/25791
Reviewed-by: Xiang Wang <wxjstz@126.com>
Reviewed-by: Philipp Hug <philipp@hug.cx>
Reviewed-by: Johanna Schander <coreboot@mimoja.de>
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

0 files changed, 0 insertions, 0 deletions