From 63060bc0a84962f2074aa30011e9d52902343172 Mon Sep 17 00:00:00 2001
From: Rimas Avizienis <rimas@eecs.berkeley.edu>
Date: Wed, 23 Jan 2013 19:27:53 -0800
Subject: [PATCH] minor tweaks for eos18 tapeout (SRAM r/w port ordering, etc)

---
 rocket/src/main/scala/ctrl.scala     | 5 ++++-
 rocket/src/main/scala/icache.scala   | 6 ++++--
 rocket/src/main/scala/nbdcache.scala | 6 +++---
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/rocket/src/main/scala/ctrl.scala b/rocket/src/main/scala/ctrl.scala
index c4b23b76..91206853 100644
--- a/rocket/src/main/scala/ctrl.scala
+++ b/rocket/src/main/scala/ctrl.scala
@@ -603,7 +603,10 @@ class Control(implicit conf: RocketConfiguration) extends Component
 
   class Scoreboard
   {
-    val r = Reg(resetVal = Bits(0))
+//    val r = Reg(resetVal = Bits(0))
+    // RIMAS: explicitly set width to 32, otherwise Chisel would set it to 1024
+    // and cause a ton of warnings during synthesis
+    val r = Reg(resetVal = Bits(0,32))
     var next = r
     var ens = Bool(false)
     def apply(addr: UFix) = r(addr)
diff --git a/rocket/src/main/scala/icache.scala b/rocket/src/main/scala/icache.scala
index 5914daac..a65cd01e 100644
--- a/rocket/src/main/scala/icache.scala
+++ b/rocket/src/main/scala/icache.scala
@@ -183,7 +183,8 @@ class ICache(implicit c: ICacheConfig, lnconf: LogicalNetworkConfiguration) exte
     val tag = c.code.encode(s2_tag)
     tag_array.write(s2_idx, Fill(c.assoc, tag), wmask)
   }
-  /*.else*/when (s0_valid) { // uncomment ".else" to infer 6T SRAM
+//  /*.else*/when (s0_valid) { // uncomment ".else" to infer 6T SRAM
+  .elsewhen (s0_valid) {
     tag_rdata := tag_array(s0_pgoff(c.untagbits-1,c.offbits))
   }
 
@@ -227,7 +228,8 @@ class ICache(implicit c: ICacheConfig, lnconf: LogicalNetworkConfiguration) exte
       val d = io.mem.grant.bits.payload.data
       data_array(Cat(s2_idx,rf_cnt)) := c.code.encode(d)
     }
-    /*.else*/when (s0_valid) { // uncomment ".else" to infer 6T SRAM
+//    /*.else*/when (s0_valid) { // uncomment ".else" to infer 6T SRAM
+    .elsewhen (s0_valid) {
       s1_dout := data_array(s0_pgoff(c.untagbits-1,c.offbits-rf_cnt.getWidth))
     }
     // if s1_tag_match is critical, replace with partial tag check
diff --git a/rocket/src/main/scala/nbdcache.scala b/rocket/src/main/scala/nbdcache.scala
index c0eac3ab..1756a706 100644
--- a/rocket/src/main/scala/nbdcache.scala
+++ b/rocket/src/main/scala/nbdcache.scala
@@ -577,15 +577,15 @@ class MetaDataArray(implicit conf: DCacheConfig) extends Component {
   val tags = Mem(conf.sets, seqRead = true) { UFix(width = metabits*conf.ways) }
   val tag = Reg{UFix()}
 
-  when (io.read.valid) {
-    tag := tags(io.read.bits.addr(conf.untagbits-1,conf.offbits))
-  }
   when (rst || io.write.valid) {
     val addr = Mux(rst, rst_cnt, io.write.bits.idx)
     val data = Cat(Mux(rst, conf.co.newStateOnFlush, io.write.bits.data.state), io.write.bits.data.tag)
     val mask = Mux(rst, Fix(-1), io.write.bits.way_en)
     tags.write(addr, Fill(conf.ways, data), FillInterleaved(metabits, mask))
   }
+  when (io.read.valid) {
+    tag := tags(io.read.bits.addr(conf.untagbits-1,conf.offbits))
+  }
 
   for (w <- 0 until conf.ways) {
     val m = tag(metabits*(w+1)-1, metabits*w)