updated itlb

rocket/src/main/scala/cpu.scala

@@ -62,13 +62,14 @@ class rocketProc extends Component
   itlb.io.cpu.status      := dpath.io.ctrl.status;
   itlb.io.cpu.req_val     := ctrl.io.imem.req_val;  
   itlb.io.cpu.req_asid    := Bits(0,ASID_BITS); // FIXME: connect to PCR
-  itlb.io.cpu.req_addr    := dpath.io.imem.req_addr;
-  io.imem.req_val         := itlb.io.cpu.resp_val;
-  io.imem.req_addr        := itlb.io.cpu.resp_addr;
+  dtlb.io.cpu.req_vpn     := dpath.io.imem.req_addr(VADDR_BITS-1,PGIDX_BITS);
+  io.imem.req_vpn         := itlb.io.cpu.resp_vpn;
   ctrl.io.imem.req_rdy    := itlb.io.cpu.req_rdy && io.imem.req_rdy;  
   ctrl.io.imem.resp_val   := io.imem.resp_val;
   dpath.io.imem.resp_data := io.imem.resp_data;
   ctrl.io.xcpt_itlb       := itlb.io.cpu.exception;
+  ctrl.io.itlb_miss       := itlb.io.cpu.resp_miss;
+
   
   // connect DTLB to D$ arbiter, ctrl+dpath
   dtlb.io.cpu.invalidate  := Bool(false); // FIXME

rocket/src/main/scala/ctrl.scala

@@ -68,6 +68,7 @@ class ioCtrlAll extends Bundle()
   val dmem    = new ioDmem(List("req_val", "req_rdy", "req_cmd", "req_type", "resp_miss")).flip();
   val host    = new ioHost(List("start"));
   val dtlb_miss = Bool('input);
+  val itlb_miss = Bool('input);
   val xcpt_dtlb_ld = Bool('input);
   val xcpt_dtlb_st = Bool('input);
   val xcpt_itlb = Bool('input);
@@ -512,7 +513,7 @@ class rocketCtrl extends Component
 
   io.dpath.stalld   := ctrl_stalld.toBool;
 
-  io.dpath.killf    := take_pc | ~io.imem.resp_val;
+  io.dpath.killf    := take_pc | io.itlb_miss | ~io.imem.resp_val;
   io.dpath.killd    := ctrl_killd.toBool;
   io.dpath.killx    := kill_ex.toBool;
   io.dpath.killm    := kill_mem.toBool;

rocket/src/main/scala/dtlb.scala

@@ -60,8 +60,6 @@ class rocketDTLB(entries: Int) extends Component
     r_cpu_req_val <== io.cpu.req_val; 
   }
   
-//   val req_vpn = r_cpu_req_addr(VADDR_BITS-1,PGIDX_BITS);
-//   val req_idx = io.cpu.req_addr(PGIDX_BITS-1,0);
   val req_load  = (r_cpu_req_cmd === M_XRD);
   val req_store = (r_cpu_req_cmd === M_XWR);
 //   val req_amo   = io.cpu.req_cmd(3).toBool;

rocket/src/main/scala/itlb.scala

@@ -73,10 +73,11 @@ class ioITLB_CPU(view: List[String] = null) extends Bundle(view)
   val req_val  = Bool('input);
   val req_rdy  = Bool('output);
   val req_asid = Bits(ASID_BITS, 'input);
-  val req_addr  = UFix(VADDR_BITS, 'input);
+  val req_vpn  = UFix(VPN_BITS, 'input);
   // lookup responses
-  val resp_val = Bool('output);
-  val resp_addr = UFix(PADDR_BITS, 'output);
+  val resp_miss = Bool('output);
+//   val resp_val = Bool('output);
+  val resp_ppn = UFix(PPN_BITS, 'output);
   val exception = Bool('output);
 }
 
@@ -94,15 +95,25 @@ class rocketITLB(entries: Int) extends Component
   val s_ready :: s_request :: s_wait :: Nil = Enum(3) { UFix() };
   val state = Reg(resetVal = s_ready);
   
-  val tag_cam = new rocketCAM(entries, addr_bits, ASID_BITS+VPN_BITS);
-  
-  val req_vpn = io.cpu.req_addr(VADDR_BITS-1,PGIDX_BITS);
-  val req_idx = io.cpu.req_addr(PGIDX_BITS-1,0);
-  val lookup_tag = Cat(io.cpu.req_asid, req_vpn);
+  val r_cpu_req_vpn     = Reg(resetVal = Bits(0, VPN_BITS));
+  val r_cpu_req_val     = Reg(resetVal = Bool(false));
+  val r_cpu_req_cmd     = Reg(resetVal = Bits(0,4));
+  val r_cpu_req_asid    = Reg(resetVal = Bits(0,ASID_BITS));
   val r_refill_tag   = Reg(resetVal = Bits(0, ASID_BITS+VPN_BITS));
   val r_refill_waddr = Reg(resetVal = UFix(0, addr_bits));
   val repl_count = Reg(resetVal = UFix(0, addr_bits));
   
+  when (io.cpu.req_val && io.cpu.req_rdy) { 
+    r_cpu_req_vpn   <== io.cpu.req_vpn;
+    r_cpu_req_asid  <== io.cpu.req_asid;
+  }
+  when (io.cpu.req_rdy) {
+    r_cpu_req_val <== io.cpu.req_val; 
+  }
+  
+  val lookup_tag = Cat(r_cpu_req_asid, r_cpu_req_vpn);
+  
+  val tag_cam = new rocketCAM(entries, addr_bits, ASID_BITS+VPN_BITS);
   val tag_ram = Mem(entries, io.ptw.resp_val, r_refill_waddr.toUFix, io.ptw.resp_ppn);
   
   tag_cam.io.clear      := io.cpu.invalidate;
@@ -110,6 +121,7 @@ class rocketITLB(entries: Int) extends Component
   tag_cam.io.write      := io.ptw.resp_val;
   tag_cam.io.write_tag  := r_refill_tag;
   tag_cam.io.write_addr := r_refill_waddr;
+  val tag_hit            = tag_cam.io.hit;
   val tag_hit_addr       = tag_cam.io.hit_addr;
   
   // extract fields from status register
@@ -144,9 +156,8 @@ class rocketITLB(entries: Int) extends Component
   
   val repl_waddr = Mux(invalid_entry, ie_addr, repl_count).toUFix;
   
-  val lookup_hit  = (state === s_ready) && io.cpu.req_val && tag_cam.io.hit;
-  val lookup_miss = (state === s_ready) && io.cpu.req_val && !tag_cam.io.hit;
-  
+  val lookup_hit  = (state === s_ready) && r_cpu_req_val && tag_hit;
+  val lookup_miss = (state === s_ready) && r_cpu_req_val && !tag_hit;
   val tlb_hit  = status_vm && lookup_hit;
   val tlb_miss = status_vm && lookup_miss;
 
@@ -165,10 +176,8 @@ class rocketITLB(entries: Int) extends Component
      (status_u && !ux_array(tag_hit_addr).toBool));
   
   io.cpu.req_rdy   := (state === s_ready);
-  io.cpu.resp_val  := Mux(status_vm, lookup_hit, io.cpu.req_val);
-  io.cpu.resp_addr  := 
-    Mux(status_vm, Cat(tag_ram(tag_hit_addr), req_idx),
-      io.cpu.req_addr(PADDR_BITS-1,0)).toUFix;
+  io.cpu.resp_miss := tlb_miss;
+  io.cpu.resp_ppn := Mux(status_vm, tag_ram(tag_hit_addr), r_cpu_req_vpn(PPN_BITS-1,0)).toUFix;
   
   io.ptw.req_val := (state === s_request);
   io.ptw.req_vpn := r_refill_tag(VPN_BITS-1,0);