RM7965A-900UI 900 MHz 64-bit Microprocessor Data Sheet
9
RM7000 and RM7965A Differences
Feature
RM7000
RM7965A
Number of CPU Cores
Pipeline Stages
1
1
5
7
Load Delay, Branch Delay
Branch Prediction
1
2
No
No
Parity
8K BHT/Core
No
Hardware Cache Coherency Support
Secondary Cache Protection
Error Checking and Correcting
(ECC)
Page Size
4 KB – 16 MB
4 KB – 256 MB
12
Number of ASID Bits
New Instructions
8
—
MSUB, MSUBU, SSNOP,
SDBBP, DERET
Integer Multiplier
Integrated Buses
SysAD Bus Width
Iterative
SysAD
Pipelined
SysAD
64-bit
64-bit (RM7000x), RM7065x) or
32-bit (RM7035C)
SysAD Maximum Bus Frequency
125 MHz (RM70xxA)
133 MHz (LVTTL) or 200 MHz
(HSTL)
133 MHz (LVTTL) or 200 MHz
(HSTL) for all RM70xxC CPUs
L3 Cache Interface
Yes (RM7000x only)
No
L3 Page Invalidate Cache Op
On-Chip Debugging
Stores TagLo register
Stores constant zero
No
Yes
Yes
Yes
Virtual
2
EJTAG Emulator Support
Integrated Instruction Trace Buffer
Watch Register Addressing
Number of Performance Counters
No
No
Physical
1
The following lists the significant additions to the RM7965A product:
The SysAD bus supports both 133 MHz LVTTL and 200 MHz HSTL SysAD bus
frequencies.
Integrated debug support includes EJTAG TAP support and on-chip trace buffers. The
added debug mechanism includes two new instructions: Software Debug Break Point
(SDBBP), and Debug Exception Return (DERET). The added debug mechanism has its own
exception vector located at 0xBFC00480 and its own 2 MB memory space at 0xFF200000.
New instructions: Multiply-Subtract, both signed and unsigned (MSUB/MSUBU), and
superscalar NOP (SSNOP) which issues a NOP to each pipeline.
Branch prediction that provides the CPU core with up to 8K entries of branch history.
Virtual Watch register addressing. This is a change from the physical Watch register
addressing on the RM7000. The two Watch registers and the Watch Mask have been
enlarged to reflect this change.
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2100294, Issue 2
53
PMC [ PMC-SIERRA, INC ]
