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.
SMIin earlier versions of the A32 assembly language.
SMIinstructions disassemble to
SMC, with a comment to say that this was formerly
This 32-bit instruction is available in A32 and T32, if the ARM architecture has the Security Extensions.
There is no 16-bit version of this instruction in T32.