Secure Monitor Call.
is an optional condition code.
is a 4-bit immediate value. This is ignored by the ARM processor, but can be used by the SMC exception handler to determine what service is being requested.
SMC was called
SMI in earlier versions of the ARM
SMI instructions disassemble to
with a comment to say that this was formerly
This ARM instruction is available in implementations of ARMv6 and above, if they have the Security Extensions.
This 32-bit Thumb instruction is available in implementations of ARMv6T2 and above, if they have the Security Extensions.
There is no 16-bit version of this instruction in Thumb.