IBM PowerPC 750GX, User Manual

Page: 112 / 377

User’s Manual
IBM PowerPC 750GX and 750GL RISC Microprocessor
Programming Model
Page 112 of 377
gx_02.fm.(1.2)
March 27, 2006
Encodings for the 750GX-specific SPRs are listed in Table 2-34.
Table 2-34. SPR Encodings for 750GX-Defined Registers (mfspr)
Register Name
SPR
1
Access mfspr/mtspr
Decimal SPR[5–9] SPR[0–4]
DABR 1013 11111 10101 User Both
HID0 1008 11111 10000 Supervisor Both
HID1 1009 11111 10001 Supervisor Both
HID2 1016 11111 11000 Supervisor Both
IABR 1010 11111 10010 Supervisor Both
ICTC 1019 11111 11011 Supervisor Both
L2CR 1017 11111 11001 Supervisor Both
MMCR0 952 11101 11000 Supervisor Both
MMCR1 956 11101 11100 Supervisor Both
PMC1 953 11101 11001 Supervisor Both
PMC2 954 11101 11010 Supervisor Both
PMC3 957 11101 11101 Supervisor Both
PMC4 958 11101 11110 Supervisor Both
Reserved
2
921–924 Supervisor
SIA 955 11101 11011 Supervisor Both
THRM1 1020 11111 11100 Supervisor Both
THRM2 1021 11111 11101 Supervisor Both
THRM3 1022 11111 11110 Supervisor Both
THRM4 920 11100 11000 Supervisor mfspr
UMMCR0 936 11101 01000 User mfspr
UMMCR1 940 11101 01100 User mfspr
UPMC1 937 11101 01001 User mfspr
UPMC2 938 11101 01010 User mfspr
UPMC3 941 11101 01101 User mfspr
UPMC4 942 11101 01110 User mfspr
USIA 939 11101 01011 User mfspr
Note:
1. The order of the two 5-bit halves of the SPR number is reversed compared with actual instruction coding.
For mtspr and mfspr instructions, the SPR number coded in assembly language does not appear directly as a 10-bit binary num-
ber in the instruction. The number coded is split into two 5-bit halves that are reversed in the instruction, with the high-order 5 bits
appearing in bits 16–20 of the instruction and the low-order 5 bits in bits 11–15.
2. These registers are reserved for future use and the contents should not be changed or reset.