Motorola M68060 User Manual page 308

Instruction Execution Timing
The following instructions perform this pipeline synchronization:
andi_to_sr
bkpt
cas
cinv
cpush
eori_to_sr
halt
lpstop
move_to_sr
movec
nop
ori_to_sr
pflush
plpa
reset
rte
stop
tas
7. Certain instructions have a variable execution time based on input operands, cache
state, etc. For these instructions, the execution time listed represents the maximum
value. These times are listed as: <= k(r/w) where k is the maximum time.
10.3 CACHE AND ATC PERFORMANCE DEGRADATION TIMES
This section defines degradation times to MC68060 processor performance for cache and
ATC miss conditions (as detailed in 10.2 Timing Assumptions , the performance numbers
in 10.1.5 Dispatch Test 5: No Register Conflicts on sOEP.AGU Resources and 10.1.6
Dispatch Test 6: No Register Conflicts on sOEP.IEE Resources assume internal cache
hits for all memory accesses). If a cache miss is encountered, the appropriate delay times
defined in this section are to be used with the instruction times defined in 10.1.5 Dispatch
Test 5: No Register Conflicts on sOEP.AGU Resources and 10.1.6 Dispatch Test 6: No
Register Conflicts on sOEP.IEE Resources to determine MC68060 execution time.
10.3.1 Instruction ATC Miss
Assumptions:
• A single, "C-index" level, normal table search (the only U-bit update possible is for the
page descriptor itself).
• Given a memory response time of "w-x-y-z" to the bus interface of the MC68060.
Instruction ATC Miss = 10+3*w(3/0), if U-bit of descriptor is already set.
Instruction ATC Miss = 18+5*w(4/1), if U-bit of descriptor must be set by the MC68060.
10-12 M68060 USER'S MANUAL MOTOROLA