refactor(el3-runtime): replace ARM_ARCH_AT_LEAST macro with FEAT flags

Replacing ARM_ARCH_AT_LEAST macro with feature specific build options
to prevent unconditional accesses to the registers during context save
and restore routines.

Registers are tightly coupled with features more than architecture
versions. Henceforth having a feature-specific build flag guarding the
respective registers, will restrict any undefined actions.

Signed-off-by: Jayanth Dodderi Chidanand <>
Change-Id: I809774df580530803c8a6e05a62d8d4de0910e02
2 files changed