Xavi/cvw
1
0
Fork 0
forked from Github_Repos/cvw
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Simplified cache fsm.

Browse Source
This commit is contained in:
Ross Thompson 2022-02-11 14:54:57 -06:00
parent 1c83914662
commit 0f2ac0cb24
1 changed files with 19 additions and 18 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
pipelined/src/cache/cachefsm.sv vendored
View File

@ -80,11 +80,11 @@ module cachefsm
logic [1:0] PreSelAdr;
logic resetDelay;
logic Read, Write, AMO;
logic AMO;
logic DoAMO, DoRead, DoWrite, DoFlush;
logic DoAMOHit, DoReadHit, DoWriteHit;
logic DoAMOMiss, DoReadMiss, DoWriteMiss;
logic FlushFlag;
logic DoAMOHit, DoReadHit, DoWriteHit, DoAnyHit;
logic DoAMOMiss, DoReadMiss, DoWriteMiss, DoAnyMiss;
logic FlushFlag, FlushWayAndNotAdrFlag;
typedef enum logic [3:0] {STATE_READY,
@ -118,15 +118,15 @@ module cachefsm
assign DoAMO = AMO & ~IgnoreRequest;
assign DoAMOHit = DoAMO & CacheHit;
assign DoAMOMiss = DoAMO & ~CacheHit;
assign Read = RW[1];
assign DoRead = Read & ~IgnoreRequest;
assign DoRead = RW[1] & ~IgnoreRequest;
assign DoReadHit = DoRead & CacheHit;
assign DoReadMiss = DoRead & ~CacheHit;
assign Write = RW[0];
assign DoWrite = Write & ~IgnoreRequest;
assign DoWrite = RW[0] & ~IgnoreRequest;
assign DoWriteHit = DoWrite & CacheHit;
assign DoWriteMiss = DoWrite & ~CacheHit;
assign DoAnyMiss = DoAMOMiss | DoReadMiss | DoWriteMiss;
assign DoAnyHit = DoAMOHit | DoReadHit | DoWriteHit;
assign FlushFlag = FlushAdrFlag & FlushWayFlag;
// outputs for the performance counters.
@ -158,7 +158,7 @@ module cachefsm
STATE_MISS_FETCH_DONE: if(VictimDirty) NextState = STATE_MISS_EVICT_DIRTY;
else NextState = STATE_MISS_WRITE_CACHE_LINE;
STATE_MISS_WRITE_CACHE_LINE: NextState = STATE_MISS_READ_WORD;
STATE_MISS_READ_WORD: if (Write & ~AMO) NextState = STATE_MISS_WRITE_WORD;
STATE_MISS_READ_WORD: if (RW[0] & ~AMO) NextState = STATE_MISS_WRITE_WORD;
else NextState = STATE_MISS_READ_WORD_DELAY;
STATE_MISS_READ_WORD_DELAY: if(AMO & CPUBusy) NextState = STATE_CPU_BUSY_FINISH_AMO;
else if(CPUBusy) NextState = STATE_CPU_BUSY;
@ -188,7 +188,7 @@ module cachefsm
// com back to CPU
assign CacheCommitted = CurrState != STATE_READY;
assign CacheStall = (CurrState == STATE_READY & (DoFlush | DoAMOMiss | DoReadMiss | DoWriteMiss)) |
assign CacheStall = (CurrState == STATE_READY & (DoFlush | DoAnyMiss)) |
(CurrState == STATE_MISS_FETCH_WDV) |
(CurrState == STATE_MISS_FETCH_DONE) |
(CurrState == STATE_MISS_WRITE_CACHE_LINE) |
@ -212,7 +212,7 @@ module cachefsm
(CurrState == STATE_MISS_READ_WORD_DELAY & AMO) |
(CurrState == STATE_MISS_WRITE_WORD);
assign FSMLineWriteEn = (CurrState == STATE_MISS_WRITE_CACHE_LINE);
assign LRUWriteEn = (CurrState == STATE_READY & (DoAMOHit | DoReadHit | DoWriteHit)) |
assign LRUWriteEn = (CurrState == STATE_READY & DoAnyHit) |
(CurrState == STATE_MISS_READ_WORD_DELAY) |
(CurrState == STATE_MISS_WRITE_WORD);
// Flush and eviction controls
@ -220,27 +220,28 @@ module cachefsm
assign SelFlush = (CurrState == STATE_FLUSH) | (CurrState == STATE_FLUSH_CHECK) |
(CurrState == STATE_FLUSH_INCR) | (CurrState == STATE_FLUSH_WRITE_BACK) |
(CurrState == STATE_FLUSH_CLEAR_DIRTY);
assign FlushAdrCntEn = (CurrState == STATE_FLUSH_CHECK & ~VictimDirty & FlushWayFlag & ~FlushAdrFlag) |
(CurrState == STATE_FLUSH_CLEAR_DIRTY & FlushWayFlag & ~FlushAdrFlag);
assign FlushWayAndNotAdrFlag = FlushWayFlag & ~FlushAdrFlag;
assign FlushAdrCntEn = (CurrState == STATE_FLUSH_CHECK & ~VictimDirty & FlushWayAndNotAdrFlag) |
(CurrState == STATE_FLUSH_CLEAR_DIRTY & FlushWayAndNotAdrFlag);
assign FlushWayCntEn = (CurrState == STATE_FLUSH_CHECK & ~VictimDirty & ~(FlushFlag)) |
(CurrState == STATE_FLUSH_CLEAR_DIRTY & ~(FlushFlag));
assign FlushAdrCntRst = (CurrState == STATE_READY);
assign FlushWayCntRst = (CurrState == STATE_READY) | (CurrState == STATE_FLUSH_INCR);
// Bus interface controls
assign CacheFetchLine = (CurrState == STATE_READY & (DoAMOMiss | DoWriteMiss | DoReadMiss));
assign CacheFetchLine = (CurrState == STATE_READY & DoAnyMiss);
assign CacheWriteLine = (CurrState == STATE_MISS_FETCH_DONE & VictimDirty) |
(CurrState == STATE_FLUSH_CHECK & VictimDirty);
// handle cpu stall.
assign restore = ((CurrState == STATE_CPU_BUSY) | (CurrState == STATE_CPU_BUSY_FINISH_AMO)) & ~`REPLAY;
assign save = ((CurrState == STATE_READY & (DoAMOHit | DoReadHit | DoWriteHit) & CPUBusy) |
(CurrState == STATE_MISS_READ_WORD_DELAY & (AMO | Read) & CPUBusy) |
assign save = ((CurrState == STATE_READY & DoAnyHit & CPUBusy) |
(CurrState == STATE_MISS_READ_WORD_DELAY & (AMO | RW[1]) & CPUBusy) |
(CurrState == STATE_MISS_WRITE_WORD & DoWrite & CPUBusy)) & ~`REPLAY;
// **** can this be simplified?
assign PreSelAdr = ((CurrState == STATE_READY & IgnoreRequestTLB) | // Ignore Request is needed on TLB miss.
(CurrState == STATE_READY & (AMO & CacheHit)) |
(CurrState == STATE_READY & (Read & CacheHit) & (CPUBusy & `REPLAY)) |
(CurrState == STATE_READY & (Write & CacheHit)) |
(CurrState == STATE_READY & (RW[1] & CacheHit) & (CPUBusy & `REPLAY)) |
(CurrState == STATE_READY & (RW[0] & CacheHit)) |
(CurrState == STATE_MISS_FETCH_WDV) |
(CurrState == STATE_MISS_FETCH_DONE) |
(CurrState == STATE_MISS_WRITE_CACHE_LINE) |