Freescale Semiconductor PowerPC e500 Core, Reference Manual

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PowerPC e500 Core Family Reference Manual, Rev. 1
3-26 Freescale Semiconductor
Instruction Model
3.3.1.4 System Linkage Instruction
The System Call (sc) instruction permits a program to call on the system to perform a service; see
Table 3-20 and Section 3.3.2.1, “System Linkage Instructions .”
Executing this instruction causes the system call interrupt handler to be invoked. For more
information, see
Section 5.7.8, “System Call Interrupt .”
3.3.1.5 Processor Control Instructions
Processor control instructions are used to read from and write to the CR, machine state register
(MSR), and special-purpose registers (SPRs).
3.3.1.5.1 Move to/from Condition Register Instructions
Table 3-21 summarizes the instructions for reading from or writing to the CR.
Implementation Note—The Book E architecture states that the Move to Condition Register
Fields (mtcrf) instruction can perform more slowly when only a portion of the fields are updated
as opposed to all the fields. This is not the case for the e500.
3.3.1.5.2 Move to/from Special-Purpose Register Instructions
Table 3-22 lists the mtspr and mfspr instructions.
Table 3-20. System Linkage Instruction
Name Mnemonic Syntax
System Call sc —
Table 3-21. Move to/from Condition Register Instructions
Name Mnemonic Syntax
Move to Condition Register Fields mtcrf CRM ,r S
Move to Condition Register from XER mcrxr cr D
Move from Condition Register mfcr r D
Table 3-22. Move to/from Special-Purpose Register Instructions
Name Mnemonic Syntax
Move to Special-Purpose Register mtspr SPR ,r S
Move from Special-Purpose Register mfspr r D , SPR