[otp, sram] Define default for dangling sram_otp_key_rsp connections

Signed-off-by: Pirmin Vogel <vogelpi@lowrisc.org>
diff --git a/hw/ip/otp_ctrl/rtl/otp_ctrl_pkg.sv b/hw/ip/otp_ctrl/rtl/otp_ctrl_pkg.sv
index 88ac020..4ef1119 100644
--- a/hw/ip/otp_ctrl/rtl/otp_ctrl_pkg.sv
+++ b/hw/ip/otp_ctrl/rtl/otp_ctrl_pkg.sv
@@ -237,12 +237,20 @@
   };
 
   typedef struct packed {
-    logic        ack;         // Ack for key.
+    logic        ack;        // Ack for key.
     sram_key_t   key;        // 128bit ephemeral scrambling key.
     sram_nonce_t nonce;      // 64bit nonce.
     logic        seed_valid; // Set to 1 if the key seed has been provisioned and is valid.
   } sram_otp_key_rsp_t;
 
+  // Default for dangling connection
+  parameter sram_otp_key_rsp_t SRAM_OTP_KEY_RSP_DEFAULT = '{
+    ack: 1'b1,
+    key: '0,
+    nonce: '0,
+    seed_valid: 1'b1
+  };
+
   typedef struct packed {
     logic        ack;        // Ack for key.
     otbn_key_t   key;        // 128bit ephemeral scrambling key.
diff --git a/hw/ip/sram_ctrl/data/sram_ctrl.hjson b/hw/ip/sram_ctrl/data/sram_ctrl.hjson
index b4ed5ee..2edd01b 100644
--- a/hw/ip/sram_ctrl/data/sram_ctrl.hjson
+++ b/hw/ip/sram_ctrl/data/sram_ctrl.hjson
@@ -75,7 +75,6 @@
       type:    "req_rsp"
       name:    "sram_otp_key"
       act:     "req"
-      default: "'0"
       package: "otp_ctrl_pkg"
     },
     // SRAM attribute input
diff --git a/hw/top_earlgrey/data/autogen/top_earlgrey.gen.hjson b/hw/top_earlgrey/data/autogen/top_earlgrey.gen.hjson
index f6e76a2..238033b 100644
--- a/hw/top_earlgrey/data/autogen/top_earlgrey.gen.hjson
+++ b/hw/top_earlgrey/data/autogen/top_earlgrey.gen.hjson
@@ -3471,8 +3471,8 @@
           type: req_rsp
           act: req
           width: 1
-          default: "'0"
           inst_name: sram_ctrl_ret_aon
+          default: ""
           top_signame: otp_ctrl_sram_otp_key
           index: 1
         }
@@ -5269,8 +5269,8 @@
           type: req_rsp
           act: req
           width: 1
-          default: "'0"
           inst_name: sram_ctrl_main
+          default: ""
           top_signame: otp_ctrl_sram_otp_key
           index: 0
         }
@@ -14866,8 +14866,8 @@
         type: req_rsp
         act: req
         width: 1
-        default: "'0"
         inst_name: sram_ctrl_ret_aon
+        default: ""
         top_signame: otp_ctrl_sram_otp_key
         index: 1
       }
@@ -15853,8 +15853,8 @@
         type: req_rsp
         act: req
         width: 1
-        default: "'0"
         inst_name: sram_ctrl_main
+        default: ""
         top_signame: otp_ctrl_sram_otp_key
         index: 0
       }