MSR (register)

Move general-purpose register to System register

This instruction allows the PE to write an AArch64 System register from a general-purpose register.

Encoding: System

313029282726252423222120191817161514131211109876543210
110101010001
Lo0op1CRnCRmop2Rt

MSR (<systemreg>|S<op0>_<op1>_<Cn>_<Cm>_<op2>), <Xt>

Decoding algorithm

constant integer t       = UInt(Rt);
constant bits(1) sys_L   = L;
constant bits(2) sys_op0 = '1' : o0;
constant bits(3) sys_op1 = op1;
constant bits(3) sys_op2 = op2;
constant bits(4) sys_crn = CRn;
constant bits(4) sys_crm = CRm;

Operation

AArch64.CheckSystemAccess(sys_op0, sys_op1, sys_crn, sys_crm, sys_op2, t, sys_L);
AArch64.SysRegWrite(sys_op0, sys_op1, sys_crn, sys_crm, sys_op2, t);

Explanations

<systemreg>: Is a System register name, encoded in "o0:op1:CRn:CRm:op2".
The System register names are defined in 'AArch64 System Registers' in the System Register XML.
<op0>: <op1>: Is a 3-bit unsigned immediate, in the range 0 to 7, encoded in the "op1" field.
<Cn>: Is a name 'Cn', with 'n' in the range 0 to 15, encoded in the "CRn" field.
<Cm>: Is a name 'Cm', with 'm' in the range 0 to 15, encoded in the "CRm" field.
<op2>: Is a 3-bit unsigned immediate, in the range 0 to 7, encoded in the "op2" field.
<Xt>: Is the 64-bit name of the general-purpose source register, encoded in the "Rt" field.