[rocketemu] set the resetvector using information from an ELF file

rocketemu/dpi/dpi.cc

@@ -50,6 +50,9 @@ void axi_read_instructionFetchAXI(
 /// true.
 void cosim_init() { dpi_call_target = cosim_init_rs(); }
 
+/// dynamically set resetvector according to the payload
+void get_resetvector() { get_resetvector_rs(dpi_call_target); }
+
 /// evaluate at every 1024 cycles, return reason = 0 to continue simulation,
 /// other value is used as error code.
 void cosim_watchdog(char *reason) {

rocketemu/dpi/dpi.h

@@ -43,6 +43,9 @@ extern void axi_read_instructionFetchAXI_rs(
 /// true. returns dpi call target
 extern void *cosim_init_rs();
 
+/// evaluate after reset, return the reset vector 
+extern void *get_resetvector_rs(void *dpi_call_target);
+
 /// evaluate at every 1024 cycles, return reason = 0 to continue simulation,
 /// other value is used as error code.
 extern void cosim_watchdog_rs(void *dpi_call_target, char *reason);

rocketemu/driver/src/dpi.rs

@@ -161,6 +161,12 @@ unsafe extern "C" fn cosim_init_rs(call_init: *mut SvBit) -> *mut () {
   Box::into_raw(sim) as *mut ()
 }
 
+#[no_mangle]
+unsafe extern "C" fn get_resetvector_rs(target: *mut ()) -> u64 {
+  let sim = &mut *(target as *mut Simulator);
+  sim.e_entry
+}
+
 #[no_mangle]
 unsafe extern "C" fn cosim_watchdog_rs(target: *mut (), reason: *mut c_char) {
   // watchdog dpi call would be called before initialization, guard on null target

rocketemu/driver/src/sim.rs

@@ -108,6 +108,7 @@ pub struct Simulator {
   pub(crate) fn_sym_tab: FunctionSymTab,
   pub(crate) dlen: u32,
   pub(crate) timeout: u64,
+  pub(crate) e_entry: u64
 
   #[cfg(feature = "trace")]
   wave_path: String,
@@ -136,8 +137,8 @@ impl Simulator {
     tracing::subscriber::set_global_default(global_logger)
       .expect("internal error: fail to setup log subscriber");
 
-    // FIXME: pass e_entry to rocket
-    let (_FIXME_e_entry, mem, fn_sym_tab) =
+    // pass e_entry to rocket
+    let (e_entry, mem, fn_sym_tab) =
       Self::load_elf(&args.elf_file).expect("fail creating simulator");
 
     #[cfg(feature = "trace")]
@@ -150,6 +151,7 @@ impl Simulator {
       dlen: option_env!("DESIGN_DLEN")
         .map(|dlen| dlen.parse().expect("fail to parse dlen into u32 digit"))
         .unwrap_or(256),
+      e_entry: e_entry,
 
       #[cfg(feature = "trace")]
       wave_path: args.wave_path.to_owned(),

rocketemu/src/TestBench.scala

@@ -68,8 +68,8 @@ class TestBench(generator: SerializableModuleGenerator[RocketTile, RocketTilePar
   dut.io.msip := 0.U
   dut.io.buserror := 0.U
 
-  // FIXME: get resetVector from simulator instead of hard code here
-  dut.io.resetVector := (BigInt(1) << 31).U
+  // get resetVector from simulator
+  dut.io.resetVector := RawUnclockedNonVoidFunctionCall("get_resetvector", Const(UInt(generator.parameter.resetVectorBits.W)))(simulationTime === 0.U)
 
   // Memory Drivers
   val instFetchAXI = dut.io.instructionFetchAXI.viewAs[AXI4ROIrrevocableVerilog]