KVM: RISC-V: SBI FWFT: Add optional init() callback for hardware probing

Add an optional init() callback to separate one-time hardware probing
from runtime availability checks. For pointer masking, this allows
probing supported PMM lengths during initialization while checking ISA
extension availability at runtime.

Fix try_to_set_pmm() to restore the previous HENVCFG.PMM value after
probing, preventing side effects from hardware detection. Add preemption
protection to ensure CSR probe sequences complete atomically on the same
CPU.

Fixes: 6f576fc0aeb9 ("RISC-V: KVM: Add support for SBI_FWFT_POINTER_MASKING_PMLEN")
Signed-off-by: Yong-Xuan Wang <yongxuan.wang@sifive.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Link: https://lore.kernel.org/r/20260601-kvm-get_reg_list-v2-v5-2-415d08a2813b@sifive.com
Signed-off-by: Anup Patel <anup@brainfault.org>

0 files changed, 0 insertions, 0 deletions