Fix illegal instruction issue #1953

Signed-off-by: Bruno Sa <[email protected]>
openhwgroup · Mar 22, 2024 · 3ba4a42 · 3ba4a42
1 parent 62bdf11
commit 3ba4a42
Showing 1 changed file with 6 additions and 4 deletions.
diff --git a/core/decoder.sv b/core/decoder.sv
@@ -291,8 +291,7 @@ module decoder
                       if (CVA6Cfg.RVH && v_i) virtual_illegal_instr = 1'b1;
                       else illegal_instr = 1'b1;
                     end
-                  end
-                  if (CVA6Cfg.RVH) begin
+                  end else if (CVA6Cfg.RVH) begin
                     if (instr.instr[31:25] == 7'b10001) begin
                       // check privilege level, HFENCE.VVMA can only be executed in M/S mode
                       // otherwise decode an illegal instruction or virtual illegal instruction
@@ -302,8 +301,7 @@ module decoder
                         illegal_instr    = (priv_lvl_i inside {riscv::PRIV_LVL_M, riscv::PRIV_LVL_S}) ? 1'b0 : 1'b1;
                       end
                       instruction_o.op = ariane_pkg::HFENCE_VVMA;
-                    end
-                    if (instr.instr[31:25] == 7'b110001) begin
+                    end else if (instr.instr[31:25] == 7'b110001) begin
                       // check privilege level, HFENCE.GVMA can only be executed in M/S mode
                       // otherwise decode an illegal instruction or virtual illegal instruction
                       if (v_i) begin
@@ -314,7 +312,11 @@ module decoder
                       instruction_o.op = ariane_pkg::HFENCE_GVMA;
                       // check TVM flag and intercept HFENCE.GVMA call if necessary
                       if (priv_lvl_i == riscv::PRIV_LVL_S && !v_i && tvm_i) illegal_instr = 1'b1;
+                    end else begin
+                      illegal_instr = 1'b1;
                     end
+                  end else begin
+                    illegal_instr = 1'b1;
                   end
                 end
               endcase