arch/riscv: add Kconfig variable RISCV_SOC_HAS_MENVCFG

Older parts do not have the menvcfg csr.
Provide a Kconfig variable, default y, to enable it.
Check the variable in the payload code, when coreboot SBI
is used, and print out if it is enabled.

The SiFive FU540 and FU740 do not support this register;
set the variable to n for those parts.

Add constants for this new CSR.

Change-Id: I6ea302a5acd98f6941bf314da89dd003ab20b596
Signed-off-by: Ronald G Minnich <rminnich@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/81425
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin L Roth <gaumless@gmail.com>

0 files changed, 0 insertions, 0 deletions