Internal Processor Registers - Compaq 21264 Hardware Reference Manual

This chapter describes 21264/EV67 internal processor registers (IPRs). They are sepa-
rated into the following circuit logic groups: Ebox, Ibox, Mbox, and Cbox.
The gray areas in register figures indicate reserved fields. Bit ranges that are coupled
with the field name specify those bits in that named field that are included in the IPR.
For example, in Figure 5–2, the field named COUNTER[31:4] contains bits 31 through
4 of the COUNTER field from Section 5.1.1. The bit range of COUNTER[31:4] in the
IPR is also listed in the column Extent in Table 5–2. In many cases, such as this one, the
bit ranges correspond. However, the bit range of the named field need not always corre-
spond to the Extent in the IPR. For example, in Figure 5–14, the field VA[47:13] resides
in IPR IVA_FORM[37:3] under the stated conditions.
The register contents after initialization are listed in Section 7.8.
Table 5–1 lists the 21264/EV67 internal processor registers.
Table 5–1 Internal Processor Registers
Register Name
Ebox IPRs
Cycle counter
Cycle counter control
Virtual address
Virtual address control
Virtual address format
Ibox IPRs
ITB tag array write
ITB PTE array write
ITB invalidate all process (ASM=0)
ITB invalidate all
ITB invalidate single
ProfileMePC
Exception address
Alpha 21264/EV67 Hardware Reference Manual

Internal Processor Registers

Index
Mnemonic (Binary)
CC 1100 0000
CC_CTL 1100 0001
VA 1100 0010
VA_CTL 1100 0100
VA_FORM 1100 0011
ITB_TAG 0000 0000
ITB_PTE 0000 0001
ITB_IAP 0000 0010
ITB_IA 0000 0011
ITB_IS 0000 0100
PMPC 0000 0101
EXC_ADDR 0000 0110
MT/MF
Score- Issued
Board from Ebox
Bit Access Pipe
5 RW 1L
5 W0 1L
4, 5, 6, 7 RO 1L
5 WO 1L
4, 5, 6, 7 RO 1L
6 WO 0L
4, 0 WO 0L
4 WO 0L
4 WO 0L
4, 6 WO 0L
— RO —
— RO 0L
Internal Processor Registers
5
Latency
for
MFPR
(Cycles)
1
—
1
—
1
—
—
—
—
—
—
3
5–1