[difftest] use t1_max_commit_interval_coefficient instead of `t1_ti…

…meout`

difftest/dpi_t1emu/src/dpi.rs

@@ -87,10 +87,6 @@ pub static ISSUE_VALID: u32 = 1;
 pub static ISSUE_FENCE: u32 = 2;
 pub static ISSUE_EXIT: u32 = 3;
 
-pub static WATCHDOG_CONTINUE: u8 = 0;
-pub static WATCHDOG_TIMEOUT: u8 = 1;
-pub static WATCHDOG_QUIT: u8 = 255;
-
 #[repr(C, packed)]
 pub(crate) struct Retire {
   pub vxsat: u32,

difftest/dpi_t1emu/src/drive.rs

@@ -105,7 +105,7 @@ pub(crate) struct Driver {
 
   pub(crate) dlen: u32,
 
-  timeout: u64,
+  max_commit_interval: u64,
 
   // driver state
   last_commit_cycle: u64,
@@ -134,7 +134,7 @@ impl Driver {
       success: false,
 
       dlen: args.dlen,
-      timeout: args.timeout,
+      max_commit_interval: args.max_commit_interval,
       last_commit_cycle: 0,
 
       issued: 0,
@@ -204,16 +204,20 @@ impl Driver {
   }
 
   pub(crate) fn watchdog(&mut self) -> u8 {
+    const WATCHDOG_CONTINUE: u8 = 0;
+    const WATCHDOG_TIMEOUT: u8 = 1;
+    const WATCHDOG_QUIT: u8 = 255;
+
     let tick = get_t();
 
     if self.success {
       trace!("[{tick}] watchdog quit");
       return WATCHDOG_QUIT;
     }
 
-    if tick - self.last_commit_cycle > self.timeout {
+    if tick - self.last_commit_cycle > self.max_commit_interval {
       error!(
-        "[{tick}] watchdog timeout (last_commit_cycle={})",
+        "[{tick}] watchdog timeout since last commit (last_commit_cycle={})",
         self.last_commit_cycle
       );
       return WATCHDOG_TIMEOUT;

difftest/dpi_t1emu/src/lib.rs

@@ -21,25 +21,29 @@ pub(crate) struct OnlineArgs {
   /// ISA config
   pub set: String,
 
-  // default to TIMEOUT_DEFAULT
-  pub timeout: u64,
+  // default to max_commit_interval * vlen / dlen
+  pub max_commit_interval: u64,
 }
 
-const TIMEOUT_DEFAULT: u64 = 100000000;
+const MAX_COMMIT_INTERVAL_COEFFICIENT: u64 = 10_0000;
 
 impl OnlineArgs {
   pub fn from_plusargs(matcher: &PlusArgMatcher) -> Self {
+    let vlen = env!("DESIGN_VLEN").parse().unwrap();
+    let dlen = env!("DESIGN_DLEN").parse().unwrap();
+    let max_commit_interval_coefficient = matcher
+      .try_match("t1_max_commit_interval_coefficient")
+      .map(|x| x.parse().unwrap())
+      .unwrap_or(MAX_COMMIT_INTERVAL_COEFFICIENT);
+    let max_commit_interval = max_commit_interval_coefficient * vlen / dlen;
+
     Self {
       elf_file: matcher.match_("t1_elf_file").into(),
       log_file: matcher.try_match("t1_log_file").map(|x| x.into()),
-
-      vlen: env!("DESIGN_VLEN").parse().unwrap(),
-      dlen: env!("DESIGN_DLEN").parse().unwrap(),
+      vlen,
+      dlen,
       set: env!("SPIKE_ISA_STRING").parse().unwrap(),
-      timeout: matcher
-        .try_match("t1_timeout")
-        .map(|x| x.parse().unwrap())
-        .unwrap_or(TIMEOUT_DEFAULT),
+      max_commit_interval,
     }
   }
 }

difftest/dpi_t1rocketemu/src/drive.rs

@@ -32,7 +32,7 @@ pub(crate) struct Driver {
   pub(crate) dlen: u32,
   pub(crate) e_entry: u64,
 
-  timeout: u64,
+  max_commit_interval: u64,
   last_commit_cycle: u64,
 
   shadow_bus: ShadowBus,
@@ -53,7 +53,7 @@ impl Driver {
       dlen: args.dlen,
       e_entry,
 
-      timeout: args.timeout,
+      max_commit_interval: args.max_commit_interval,
       last_commit_cycle: 0,
 
       shadow_bus,
@@ -254,9 +254,9 @@ impl Driver {
       return WATCHDOG_QUIT;
     }
 
-    if tick - self.last_commit_cycle > self.timeout {
+    if tick - self.last_commit_cycle > self.max_commit_interval {
       error!(
-        "[{tick}] watchdog timeout (last_commit_cycle={})",
+        "[{tick}] watchdog timeout since last commit (last_commit_cycle={})",
         self.last_commit_cycle
       );
       return WATCHDOG_TIMEOUT;

difftest/dpi_t1rocketemu/src/lib.rs

@@ -13,21 +13,24 @@ pub(crate) struct OnlineArgs {
   /// dlen config
   pub dlen: u32,
 
-  // default to TIMEOUT_DEFAULT
-  pub timeout: u64,
+  // default to max_commit_interval
+  pub max_commit_interval: u64,
 }
 
-const TIMEOUT_DEFAULT: u64 = 100000000;
+const MAX_COMMIT_INTERVAL_COEFFICIENT: u64 = 10_0000;
 
 impl OnlineArgs {
   pub fn from_plusargs(matcher: &PlusArgMatcher) -> Self {
+    let max_commit_interval_coefficient = matcher
+      .try_match("t1_max_commit_interval_coefficient")
+      .map(|x| x.parse().unwrap())
+      .unwrap_or(MAX_COMMIT_INTERVAL_COEFFICIENT);
+    let max_commit_interval = max_commit_interval_coefficient;
+
     Self {
       elf_file: matcher.match_("t1_elf_file").into(),
       dlen: env!("DESIGN_DLEN").parse().unwrap(),
-      timeout: matcher
-        .try_match("t1_timeout")
-        .map(|x| x.parse().unwrap())
-        .unwrap_or(TIMEOUT_DEFAULT),
+      max_commit_interval,
     }
   }
 }

script/emu/src/Main.scala

@@ -174,9 +174,9 @@ object Main:
       doc = "Print the final emulator command line and exit"
     ) dryRun:   Flag = Flag(false),
     @arg(
-      name = "timeout",
+      name = "max-commit-interval-coefficient",
       doc = "Specify maximum cycle count limit"
-    ) timeout:  Option[Int] = None,
+    ) maxCommitIntervalCoefficient:  Option[Int] = None,
     leftOver:   Leftover[String]
   ): Unit =
     if leftOver.value.isEmpty then Logger.fatal("No test case name")
@@ -219,7 +219,7 @@ object Main:
       emulator.toString(),
       s"+t1_elf_file=${caseElfPath}"
     )
-      ++ optionals(timeout.isDefined, Seq(s"+t1_timeout=${timeout.getOrElse("unreachable")}"))
+      ++ optionals(maxCommitIntervalCoefficient.isDefined, Seq(s"+t1_max_commit_interval_coefficient=${maxCommitIntervalCoefficient.getOrElse("unreachable")}"))
       ++ optionals(isTrace, Seq(s"+t1_wave_path=${outputPath / "wave.fsdb"}"))
       ++ optionals(isCover, Seq(s"-cm assert"))
       ++ optionals(!leftOverArguments.isEmpty, leftOverArguments)

t1rocketemu/vsrc/ClockGen.sv

@@ -43,7 +43,7 @@ module ClockGen(
 
     // Args:
     //   +t1_elf_file=... : path of elf file
-    //   +t1_timeout=... : (optional) max interval of inst commit, counted in cycle
+    //   +t1_max_commit_interval_coefficient=... : (optional) max interval of inst commit, counted in cycle
     t1_cosim_init();
 
   `ifdef T1_ENABLE_TRACE