Implement mcontrol trigger hit bit.

1 files changed, 12 insertions, 0 deletions

diff --git a/riscv/triggers.cc b/riscv/triggers.cc
index 7f6be44..ed9105e 100644
--- a/riscv/triggers.cc
+++ b/riscv/triggers.cc
@@ -1,3 +1,4 @@
+#include "debug_defines.h"
 #include "processor.h"
 #include "triggers.h"
 
@@ -16,6 +17,7 @@ reg_t mcontrol_t::tdata1_read(const processor_t * const proc) const noexcept {
   v = set_field(v, MCONTROL_TYPE(xlen), 2);
   v = set_field(v, MCONTROL_DMODE(xlen), dmode);
   v = set_field(v, MCONTROL_MASKMAX(xlen), 0);
+  v = set_field(v, CSR_MCONTROL_HIT, hit);
   v = set_field(v, MCONTROL_SELECT, select);
   v = set_field(v, MCONTROL_TIMING, timing);
   v = set_field(v, MCONTROL_ACTION, action);
@@ -36,6 +38,7 @@ bool mcontrol_t::tdata1_write(processor_t * const proc, const reg_t val) noexcep
   }
   auto xlen = proc->get_xlen();
   dmode = get_field(val, MCONTROL_DMODE(xlen));
+  hit = get_field(val, CSR_MCONTROL_HIT);
   select = get_field(val, MCONTROL_SELECT);
   timing = get_field(val, MCONTROL_TIMING);
   action = (triggers::action_t) get_field(val, MCONTROL_ACTION);
@@ -131,6 +134,9 @@ match_result_t mcontrol_t::memory_access_match(processor_t * const proc, operati
   }
 
   if (simple_match(xlen, value)) {
+    /* This is OK because this function is only called if the trigger was not
+     * inhibited by the previous trigger in the chain. */
+    hit = true;
     if (timing)
       return MATCH_FIRE_AFTER;
     else
@@ -165,6 +171,12 @@ match_result_t module_t::memory_access_match(action_t * const action, operation_
       continue;
     }
 
+    /* Note: We call memory_access_match for each trigger in a chain as long as
+     * the triggers are matching. This results in "temperature coding" so that
+     * `hit` is set on each of the consecutive triggers that matched, even if the
+     * entire chain did not match. This is allowed by the spec, because the final
+     * trigger in the chain will never get `hit` set unless the entire chain
+     * matches. */
     match_result_t result = triggers[i]->memory_access_match(proc, operation, address, data);
     if (result != MATCH_NONE && !triggers[i]->chain()) {
       *action = triggers[i]->action;