2/5/2002
CS 269  Hardware and Software Engineering of Embedded Systems
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Hardware Implemenation
lFirst Xtensa implementation with traditional RISC five stage pipeline.
lProcessor accesses instruction cache and tags in first half of I stage.  Computes cache hit/miss signal in 2nd half.
lInstruction is decoded and register file is accessed in R stage.
lMachine computes  effective address for loads and stores and executes ALU instructions on E stage and also determines if conditional branch is taken.
lFor loads, the processor accesses data cache in the first half o the M stage and computes the cache hit/miss signal in 2nd half.
lRegister file is updated in W stage.
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