mpc604e Freescale Semiconductor, Inc, mpc604e Datasheet - Page 6

• Manufacturer Part Number: mpc604e
• Description: Powerpc 604e-tm Risc Microprocessor Technical Summary
• Manufacturer: Freescale Semiconductor, Inc

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— Three-stage floating-point unit (FPU)
— Load/store unit (LSU)
Rename buffers
— Twelve GPR rename buffers
— Eight FPR rename buffers
— Eight condition register (CR) rename buffers
The 604e rename buffers are described in Section 1.2.7, “Rename Buffers.”
Completion unit
— The completion unit retires an instruction from the 16-entry reorder buffer when all instructions
— Guarantees sequential programming model (precise exception model)
— Monitors all dispatched instructions and retires them in order
— Tracks unresolved branches and flushes executed, dispatched, and fetched instructions if branch
— Retires as many as four instructions per clock
Separate on-chip instruction and data caches (Harvard architecture)
— 32-Kbyte, four-way set-associative instruction and data caches
— LRU replacement algorithm
— 32-byte (eight-word) cache block size
— Physically indexed/physical tags. (Note that the PowerPC architecture refers to physical
— Cache write-back or write-through operation programmable on a per page or per block basis
— Instruction cache can provide four instructions per clock; data cache can provide two words per
— Caches can be disabled in software
– Fully IEEE 754-1985-compliant FPU for both single- and double-precision operations
– Supports non-IEEE mode for time-critical operations
– Fully pipelined, single-pass double-precision design
– Hardware support for denormalized numbers
– Two-entry reservation station to minimize stalls
– Thirty-two 64-bit FPRs for single- or double-precision operands
– Two-entry reservation station to minimize stalls
– Single-cycle, pipelined cache access
– Dedicated adder performs EA calculations
– Performs alignment and precision conversion for floating-point data
– Performs alignment and sign extension for integer data
– Four-entry finish load queue (FLQ) provides load miss buffering
– Six-entry store queue
– Supports both big- and little-endian modes
ahead of it have been completed and the instruction has finished execution.
is mispredicted
address space as real address space.)
clock
PowerPC 604e RISC Microprocessor Technical Summary