
IBM3206K0424
IBM Processor for Network Resources
Preliminary
Processor Core (PCORE)
Page 450 of 676
pnr25.chapt05.01
August 14, 2000
Cobra Facilities Overview
The following registers are patterned after the registers in either the PowerPC 603 User
’
s Manual
(MPR603UMU-01,MPC603UM/AD) or the Power PC 401 Core User
’
s Manual (v0.07 1/28/978). Differences
between the two implementations and the Cobra Core implementations are detailed below.
The registers are split into these functional groupings: Machine Control/Status Registers, Branch Control
Registers, Debug Control Registers, Special Purpose Facilities, Interrupt and Exception Registers, Timer
Registers, Cache Control Registers, and Translation Control Registers.
Source Key:
BOTH - same bit definitions as 603 and 401
401 - same bit definitions as 401
603 - same bit definitions as 603
PPC - same bit definitions as general Power PC architecture
COBRA - COBRA Configuration
Cobra Instruction Changes
Instruction(s)
Source
Description
dccci, icbt, iccci
401
Added for cache management
mfdcr, mtdcr
401
Added for DCR bus support
rfci, wrtee, wrteei
401
Added for 40x interrupt support
mfsr, mfsrin, mtsr, mtsrin
603
Added for 60x MMU support (not supported this pass)
mftb
603
Added for 60x style time base support
tlbie
603
Added for 60x MMU support (not supported this pass)
tlbsync
603
Added for 60x compatibility, acts as a no-op
mfbus, mtbus
Cobra Core
Added - See Appendix: New instructions
dcread, icread
401
Removed - cache layout is different
dcba
405
Not Supported - 405 only instruction
tlbre, tlbsx(.), tlbwe
405
Removed - 40x style MMU not supported
eciwx, ecowx
603
Removed - only memory space addressing supported
fxxxxx
603
Removed floating point support
lfd, lfdu, lfdux, lfdx, lfs, lfsu, lfsux, lfsx
603
Removed floating point support
mffs, mffsb0, mffsb1, mffsf, mffsfi
603
Removed floating point support
stfd, stfdu, stfdux, stfdx, stfiwx, stfs,
stfsu, stfsux, stfsx
603
Removed floating point support
tlbld, tlbli
603
Removed - 603 style MMU support, may add next pass