Merge branch 'main' of github.com:ross144/cvw into main

src/cache/cache.sv

@@ -39,7 +39,7 @@ module cache #(parameter LINELEN,  NUMLINES,  NUMWAYS, LOGBWPL, WORDLEN, MUXINTE
   input  logic [1:0]             CacheAtomic,       // Atomic operation
   input  logic                   FlushCache,        // Flush all dirty lines back to memory
   input  logic                   InvalidateCache,   // Clear all valid bits
-  input  logic [11:0]            NextAdr,           // Virtual address, but we only use the lower 12 bits.
+  input  logic [11:0]            NextSet,           // Virtual address, but we only use the lower 12 bits.
   input  logic [`PA_BITS-1:0]    PAdr,              // Physical address
   input  logic [(WORDLEN-1)/8:0] ByteMask,          // Which bytes to write (D$ only)
   input  logic [WORDLEN-1:0]     CacheWriteData,    // Data to write to cache (D$ only)
@@ -50,7 +50,7 @@ module cache #(parameter LINELEN,  NUMLINES,  NUMWAYS, LOGBWPL, WORDLEN, MUXINTE
   output logic                   CacheMiss,         // Cache miss
   output logic                   CacheAccess,       // Cache access
   // lsu control
-  input  logic                   SelHPTW,           // Use PAdr from Hardware Page Table Walker rather than NextAdr
+  input  logic                   SelHPTW,           // Use PAdr from Hardware Page Table Walker rather than NextSet
   // Bus fsm interface
   input  logic                   CacheBusAck,       // Bus operation completed
   input  logic                   SelBusBeat,        // Word in cache line comes from BeatCount
@@ -74,7 +74,7 @@ module cache #(parameter LINELEN,  NUMLINES,  NUMWAYS, LOGBWPL, WORDLEN, MUXINTE
 
   logic                          SelAdr;
   logic [1:0]                    AdrSelMuxSel;
-  logic [SETLEN-1:0]             CAdr;
+  logic [SETLEN-1:0]             CacheSet;
   logic [LINELEN-1:0]            LineWriteData;
   logic                          ClearValid, ClearDirty, SetDirty, SetValid;
   logic [LINELEN-1:0]            ReadDataLineWay [NUMWAYS-1:0];
@@ -106,24 +106,24 @@ module cache #(parameter LINELEN,  NUMLINES,  NUMWAYS, LOGBWPL, WORDLEN, MUXINTE
   // Read Path
   /////////////////////////////////////////////////////////////////////////////////////////////
 
-  // Choose read address (CAdr).  Normally use NextAdr, but use PAdr during stalls
+  // Choose read address (CacheSet).  Normally use NextSet, but use PAdr during stalls
   // and FlushAdr when handling D$ flushes
   // The icache must update to the newest PCNextF on flush as it is probably a trap.  Trap
   // sets PCNextF to XTVEC and the icache must start reading the instruction.
   assign AdrSelMuxSel = {SelFlush, ((SelAdr | SelHPTW) & ~((READ_ONLY_CACHE == 1) & FlushStage))};
-  mux3 #(SETLEN) AdrSelMux(NextAdr[SETTOP-1:OFFSETLEN], PAdr[SETTOP-1:OFFSETLEN], FlushAdr,
+  mux3 #(SETLEN) AdrSelMux(NextSet[SETTOP-1:OFFSETLEN], PAdr[SETTOP-1:OFFSETLEN], FlushAdr,
-    AdrSelMuxSel, CAdr);
+    AdrSelMuxSel, CacheSet);
 
   // Array of cache ways, along with victim, hit, dirty, and read merging logic
   cacheway #(NUMLINES, LINELEN, TAGLEN, OFFSETLEN, SETLEN, READ_ONLY_CACHE) CacheWays[NUMWAYS-1:0](
-    .clk, .reset, .CacheEn, .CAdr, .PAdr, .LineWriteData, .LineByteMask,
+    .clk, .reset, .CacheEn, .CacheSet, .PAdr, .LineWriteData, .LineByteMask,
     .SetValid, .ClearValid, .SetDirty, .ClearDirty, .SelWriteback, .VictimWay,
     .FlushWay, .SelFlush, .ReadDataLineWay, .HitWay, .ValidWay, .DirtyWay, .TagWay, .FlushStage, .InvalidateCache);
 
   // Select victim way for associative caches
   if(NUMWAYS > 1) begin:vict
     cacheLRU #(NUMWAYS, SETLEN, OFFSETLEN, NUMLINES) cacheLRU(
-      .clk, .reset, .CacheEn, .FlushStage, .HitWay, .ValidWay, .VictimWay, .CAdr, .LRUWriteEn(LRUWriteEn & ~FlushStage),
+      .clk, .reset, .CacheEn, .FlushStage, .HitWay, .ValidWay, .VictimWay, .CacheSet, .LRUWriteEn(LRUWriteEn & ~FlushStage),
       .SetValid, .PAdr(PAdr[SETTOP-1:OFFSETLEN]), .InvalidateCache, .FlushCache);
   end else 
     assign VictimWay = 1'b1; // one hot.

src/cache/cacheLRU.sv

@@ -37,7 +37,7 @@ module cacheLRU
   input  logic                CacheEn,         // Enable the cache memory arrays.  Disable hold read data constant
   input  logic [NUMWAYS-1:0]  HitWay,          // Which way is valid and matches PAdr's tag
   input  logic [NUMWAYS-1:0]  ValidWay,        // Which ways for a particular set are valid, ignores tag
-  input  logic [SETLEN-1:0]   CAdr,            // Cache address, the output of the address select mux, NextAdr, PAdr, or FlushAdr
+  input  logic [SETLEN-1:0]   CacheSet,            // Cache address, the output of the address select mux, NextAdr, PAdr, or FlushAdr
   input  logic [SETLEN-1:0]   PAdr,            // Physical address 
   input  logic                LRUWriteEn,      // Update the LRU state
   input  logic                SetValid,        // Set the dirty bit in the selected way and set
@@ -124,8 +124,7 @@ module cacheLRU
 
   // LRU storage must be reset for modelsim to run. However the reset value does not actually matter in practice.
   // This is a two port memory.
-  // Every cycle must read from CAdr and each load/store must write the new LRU.
+  // Every cycle must read from CacheSet and each load/store must write the new LRU.
-  // this is still wrong.***************************
   always_ff @(posedge clk) begin
     if (reset) for (int set = 0; set < NUMLINES; set++) LRUMemory[set] <= '0;
     if(CacheEn) begin
@@ -133,10 +132,10 @@ module cacheLRU
       else if (LRUWriteEn & ~FlushStage) begin 
         LRUMemory[PAdr] <= NextLRU;
       end
-      if(LRUWriteEn & ~FlushStage & (PAdr == CAdr))
+      if(LRUWriteEn & ~FlushStage & (PAdr == CacheSet))
         CurrLRU <= #1 NextLRU;
       else 
-        CurrLRU <= #1 LRUMemory[CAdr];
+        CurrLRU <= #1 LRUMemory[CacheSet];
     end
   end
 

src/cache/cacheway.sv

@@ -35,7 +35,7 @@ module cacheway #(parameter NUMLINES=512, LINELEN = 256, TAGLEN = 26,
   input  logic                        reset,
   input  logic                        FlushStage,     // Pipeline flush of second stage (prevent writes and bus operations)
   input  logic                        CacheEn,        // Enable the cache memory arrays.  Disable hold read data constant
-  input  logic [$clog2(NUMLINES)-1:0] CAdr,           // Cache address, the output of the address select mux, NextAdr, PAdr, or FlushAdr
+  input  logic [$clog2(NUMLINES)-1:0] CacheSet,           // Cache address, the output of the address select mux, NextAdr, PAdr, or FlushAdr
   input  logic [`PA_BITS-1:0]         PAdr,           // Physical address 
   input  logic [LINELEN-1:0]          LineWriteData,  // Final data written to cache (D$ only)
   input  logic                        SetValid,       // Set the dirty bit in the selected way and set
@@ -114,7 +114,7 @@ module cacheway #(parameter NUMLINES=512, LINELEN = 256, TAGLEN = 26,
   /////////////////////////////////////////////////////////////////////////////////////////////
 
   ram1p1rwbe #(.DEPTH(NUMLINES), .WIDTH(TAGLEN)) CacheTagMem(.clk, .ce(CacheEn),
-    .addr(CAdr), .dout(ReadTag), .bwe('1),
+    .addr(CacheSet), .dout(ReadTag), .bwe('1),
     .din(PAdr[`PA_BITS-1:OFFSETLEN+INDEXLEN]), .we(SetValidEN));
 
   
@@ -136,7 +136,7 @@ module cacheway #(parameter NUMLINES=512, LINELEN = 256, TAGLEN = 26,
   localparam           LOGNUMSRAM = $clog2(NUMSRAM);
   
   for(words = 0; words < NUMSRAM; words++) begin: word
-    ram1p1rwbe #(.DEPTH(NUMLINES), .WIDTH(SRAMLEN)) CacheDataMem(.clk, .ce(CacheEn), .addr(CAdr),
+    ram1p1rwbe #(.DEPTH(NUMLINES), .WIDTH(SRAMLEN)) CacheDataMem(.clk, .ce(CacheEn), .addr(CacheSet),
       .dout(ReadDataLine[SRAMLEN*(words+1)-1:SRAMLEN*words]),
       .din(LineWriteData[SRAMLEN*(words+1)-1:SRAMLEN*words]),
       .we(SelectedWriteWordEn), .bwe(FinalByteMask[SRAMLENINBYTES*(words+1)-1:SRAMLENINBYTES*words]));
@@ -152,9 +152,9 @@ module cacheway #(parameter NUMLINES=512, LINELEN = 256, TAGLEN = 26,
   always_ff @(posedge clk) begin // Valid bit array, 
     if (reset) ValidBits        <= #1 '0;
     if(CacheEn) begin 
-	  ValidWay <= #1 ValidBits[CAdr];
+	  ValidWay <= #1 ValidBits[CacheSet];
 	  if(InvalidateCache)                    ValidBits <= #1 '0;
-      else if (SetValidEN | (ClearValidWay & ~FlushStage)) ValidBits[CAdr] <= #1 SetValidWay;
+      else if (SetValidEN | (ClearValidWay & ~FlushStage)) ValidBits[CacheSet] <= #1 SetValidWay;
     end
   end
 
@@ -168,8 +168,8 @@ module cacheway #(parameter NUMLINES=512, LINELEN = 256, TAGLEN = 26,
       // reset is optional.  Consider merging with TAG array in the future.
       //if (reset) DirtyBits <= #1 {NUMLINES{1'b0}}; 
       if(CacheEn) begin
-        Dirty <= #1 DirtyBits[CAdr];
+        Dirty <= #1 DirtyBits[CacheSet];
-        if((SetDirtyWay | ClearDirtyWay) & ~FlushStage) DirtyBits[CAdr] <= #1 SetDirtyWay;
+        if((SetDirtyWay | ClearDirtyWay) & ~FlushStage) DirtyBits[CacheSet] <= #1 SetDirtyWay;
       end
     end
   end else assign Dirty = 1'b0;

src/hazard/hazard.sv

@@ -43,7 +43,7 @@ module hazard (
 );
 
   logic                                       StallFCause, StallDCause, StallECause, StallMCause, StallWCause;
-  logic                                       FirstUnstalledD, FirstUnstalledE, FirstUnstalledM, FirstUnstalledW;
+  logic                                       LatestUnstalledD, LatestUnstalledE, LatestUnstalledM, LatestUnstalledW;
   logic                                       FlushDCause, FlushECause, FlushMCause, FlushWCause;
   
   // stalls and flushes
@@ -95,14 +95,14 @@ module hazard (
   assign #1 StallW = StallWCause;
 
   // detect the first stage that is not stalled
-  assign FirstUnstalledD = ~StallD & StallF;
+  assign LatestUnstalledD = ~StallD & StallF;
-  assign FirstUnstalledE = ~StallE & StallD;
+  assign LatestUnstalledE = ~StallE & StallD;
-  assign FirstUnstalledM = ~StallM & StallE;
+  assign LatestUnstalledM = ~StallM & StallE;
-  assign FirstUnstalledW = ~StallW & StallM;
+  assign LatestUnstalledW = ~StallW & StallM;
   
   // Each stage flushes if the previous stage is the last one stalled (for cause) or the system has reason to flush
-  assign #1 FlushD = FirstUnstalledD | FlushDCause; 
+  assign #1 FlushD = LatestUnstalledD | FlushDCause; 
-  assign #1 FlushE = FirstUnstalledE | FlushECause;
+  assign #1 FlushE = LatestUnstalledE | FlushECause;
-  assign #1 FlushM = FirstUnstalledM | FlushMCause;
+  assign #1 FlushM = LatestUnstalledM | FlushMCause;
-  assign #1 FlushW = FirstUnstalledW | FlushWCause;
+  assign #1 FlushW = LatestUnstalledW | FlushWCause;
 endmodule

src/ifu/ifu.sv

@@ -245,7 +245,7 @@ module ifu (
              .CacheWriteData('0),
              .CacheRW(CacheRWF), 
              .CacheAtomic('0), .FlushCache('0),
-             .NextAdr(PCSpillNextF[11:0]),
+             .NextSet(PCSpillNextF[11:0]),
              .PAdr(PCPF),
              .CacheCommitted(CacheCommittedF), .InvalidateCache(InvalidateICacheM));
       ahbcacheinterface #(WORDSPERLINE, LOGBWPL, LINELEN, LLENPOVERAHBW) 

src/lsu/lsu.sv

@@ -266,7 +266,7 @@ module lsu (
       cache #(.LINELEN(`DCACHE_LINELENINBITS), .NUMLINES(`DCACHE_WAYSIZEINBYTES*8/LINELEN),
               .NUMWAYS(`DCACHE_NUMWAYS), .LOGBWPL(LLENLOGBWPL), .WORDLEN(`LLEN), .MUXINTERVAL(`LLEN), .READ_ONLY_CACHE(0)) dcache(
         .clk, .reset, .Stall(GatedStallW), .SelBusBeat, .FlushStage(FlushW), .CacheRW(CacheRWM), .CacheAtomic(CacheAtomicM),
-        .FlushCache(FlushDCache), .NextAdr(IEUAdrE[11:0]), .PAdr(PAdrM), 
+        .FlushCache(FlushDCache), .NextSet(IEUAdrE[11:0]), .PAdr(PAdrM), 
         .ByteMask(ByteMaskM), .BeatCount(BeatCount[AHBWLOGBWPL-1:AHBWLOGBWPL-LLENLOGBWPL]),
         .CacheWriteData(LSUWriteDataM), .SelHPTW,
         .CacheStall(DCacheStallM), .CacheMiss(DCacheMiss), .CacheAccess(DCacheAccess),