mc68ec060 Freescale Semiconductor, Inc, mc68ec060 Datasheet - Page 118

• Manufacturer Part Number: mc68ec060
• Description: Mc68060 Superscalar 68k Microprocessor Including The Lc060 And Ec060
• Manufacturer: Freescale Semiconductor, Inc

Caches
5-19
back Mode)
(Writethrou
(Writethrou
OPU Read
OPU Read
OPU Write
(Copyback
OPU Write
OPU Write
OPU Write
Operation
Hit (Copy-
Snoop Hit
gh Mode)
gh Mode)
Cache In-
Alternate
validate
Master
Cache
Cache
Mode)
Push
Miss
Miss
Miss
Hit
Hit
(C,W)I1
(C,W)I2 Not possible.
(C,W)I7 Not possible.
(C,W)I5 No action; Remain in cur-
(C,W)I6 No action; Remain in cur-
WI3
WI4
CI3
CI4
Read line from memory
and update cache; Sup-
ply data to OPU; Go to
valid state.
Read line from memory
and update cache; Write
data to cache; Go to dirty
state.
Write data to memory;
Remain in current state.
Not possible.
Not possible.
rent state.
rent state.
Invalid Cases
Table 5-3. Data Cache Line State Transitions
M68060 USER’S MANUAL
(C,W)V1
(C,W)V2 Supply data to OPU; Re-
(C,W)V5 No action; Go to invalid
(C,W)V6 No action; Go to invalid
(C,W)V7 No action; Go to invalid
WV3
WV4
CV3
CV$
Current State
Read new line from mem-
ory and update cache;
supply data to OPU; Re-
main in current state.
main in current state.
Read new line from mem-
ory and update cache;
Write data to cache; Go
to dirty state.
Write data to memory;
Remain in current state.
Write data to cache; Go
to dirty state.
Write data to memory
and to cache; Remain in
current state.
state.
state.
state.
Valid Cases
CD1
CD2 Supply data to OPU; Re-
CD3
CD4 Write data to cache; Re-
CD5 No action (dirty data lost);
CD6
CD7 No action (dirty data lost);
WD
WD
3
4
Push dirty cache line to
push buffer; Read new
line from memory and up-
date cache; Supply data
to OPU; Write push buffer
contents to memory; Go
to valid state.
main in current state.
Push dirty cache line to
push buffer; Read new
line from memory and up-
date cache; Write push
buffer contents to memo-
ry; Remain in current
state.
Write data to memory;
Remain in current state.
main in current state.
Push dirty cache line to
memory; Write data to
memory and to cache;
Go to valid state.
Go to invalid state.
Push dirty cache line to
memory; Go to invalid
state or remain in current
state, depending on the
DPI bit the the CACR.
Go to invalid state.
Dirty Cases
MOTOROLA