• Punit Agrawal's avatar
    arm64: Emulate CP15 Barrier instructions · c852f320
    Punit Agrawal authored
    The CP15 barrier instructions (CP15ISB, CP15DSB and CP15DMB) are
    deprecated in the ARMv7 architecture, superseded by ISB, DSB and DMB
    instructions respectively. Some implementations may provide the
    ability to disable the CP15 barriers by disabling the CP15BEN bit in
    SCTLR_EL1. If not enabled, the encodings for these instructions become
    undefined.
    
    To support legacy software using these instructions, this patch
    register hooks to -
    * emulate CP15 barriers and warn the user about their use
    * toggle CP15BEN in SCTLR_EL1
    Signed-off-by: default avatarPunit Agrawal <punit.agrawal@arm.com>
    Reviewed-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
    Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
    c852f320
armv8_deprecated.c 12.2 KB