From 1b93e7f569c61d0dbe26492f0357d46db2ff56b1 Mon Sep 17 00:00:00 2001
From: mariusmonton <marius.monton@gmail.com>
Date: Sun, 25 Nov 2018 12:07:08 +0100
Subject: [PATCH] added time management and cycle counters

---
 inc/Registers.h   | 10 ++++++++++
 src/CPU.cpp       |  2 ++
 src/Registers.cpp |  2 --
 src/Simulator.cpp |  3 +++
 4 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/inc/Registers.h b/inc/Registers.h
index 5f2eb22..2f07206 100644
--- a/inc/Registers.h
+++ b/inc/Registers.h
@@ -41,6 +41,16 @@
 #define CSR_MTVAL (0x343)
 #define CSR_MIP (0x344)
 
+#define CSR_CYCLE (0xC00)
+#define CSR_TIME (0xC01)
+#define CSR_INSTRET (0xC02)
+
+#define CSR_CYCLEH (0xC80)
+#define CSR_TIMEH (0xC81)
+#define CSR_INSTRETH (0xC02)
+
+/* 1 ns tick in CYCLE & TIME counters */
+#define TICKS_PER_SECOND (1000000)
 
 using namespace sc_core;
 using namespace sc_dt;
diff --git a/src/CPU.cpp b/src/CPU.cpp
index cc73d10..fe10425 100644
--- a/src/CPU.cpp
+++ b/src/CPU.cpp
@@ -393,6 +393,8 @@ void CPU::CPU_thread(void) {
             inst.dump();
             exec->NOP(inst);
           } // switch (inst.check_extension())
+          /* Fixed instruction time to 10 ns (i.e. 100 MHz)*/
+          sc_core::wait(10, SC_NS);
         }
 
         perf->instructionsInc();
diff --git a/src/Registers.cpp b/src/Registers.cpp
index aa46d67..a9d5865 100644
--- a/src/Registers.cpp
+++ b/src/Registers.cpp
@@ -99,12 +99,10 @@ uint32_t Registers::getCSR(int csr) {
     case CSR_TIME:
       ret_value = (uint64_t)(sc_time(sc_time_stamp()
           - sc_time(SC_ZERO_TIME)).to_double()) & 0x00000000FFFFFFFF;
-      cout << "TIME " << ret_value << endl;
       break;
     case CSR_TIMEH:
       ret_value = (uint32_t)((uint64_t)(sc_time(sc_time_stamp()
           - sc_time(SC_ZERO_TIME)).to_double()) >> 32 & 0x00000000FFFFFFFF);
-      cout << "TIMEH " << ret_value << endl;
       break;
     default:
       ret_value = CSR[csr];
diff --git a/src/Simulator.cpp b/src/Simulator.cpp
index 63b5214..16aab82 100644
--- a/src/Simulator.cpp
+++ b/src/Simulator.cpp
@@ -82,6 +82,9 @@ int sc_main(int argc, char* argv[])
 
   signal(SIGINT, intHandler);
 
+  /* SystemC time resolution set to 1 ns*/
+  sc_set_time_resolution(1, SC_NS);
+
   if (argv[1] == nullptr) {
     cerr << "Filename needed for hex memory" << endl;
     return -1;