forked from Mirrors/opensbi

On some platforms, misa may not be implemented. On such a platform, reading misa will get 0. At this time, platform is required to implement a non-standard function to detect the CPU's capabilities. Therefore, this modification add interfaces for non-standard function. The MXL field of misa is always at the highest two bits, whether it is a 32-bit 64-bit or a 128-bit machine. Therefore, this modification fixes the use of a fixed offset to detect the machine length. Signed-off-by: Xiang Wang <merle@hardenedlinux.org> Signed-off-by: Anup Patel <anup.patel@wdc.com>