fix JTAG capture on Atmel-ICE

src/jtag3.h

@@ -89,9 +89,12 @@ enum jtag3consts
     RSP3_FAIL_PDI = 0x1B,
     RSP3_FAIL_NO_ANSWER = 0x20,
     RSP3_FAIL_NO_TARGET_POWER = 0x22,
-    RSP3_FAIL_WRONG_MODE = 0x32,    /* CPU running vs. stopped */
-    RSP3_FAIL_UNSUPP_MEMORY = 0x34, /* unsupported memory type */
-    RSP3_FAIL_WRONG_LENGTH = 0x35,  /* wrong lenth for mem access */
+    RSP3_FAIL_NOT_ATTACHED = 0x23,     /* Must run attach command first */
+    RSP3_FAIL_WRONG_MODE = 0x32,       /* CPU running vs. stopped */
+    RSP3_FAIL_UNSUPP_MEMORY = 0x34,    /* unsupported memory type */
+    RSP3_FAIL_WRONG_LENGTH = 0x35,     /* wrong length for mem access */
+    RSP3_FAIL_TIMEOUT = 0x3C,          /* A timeout occurred */
+    RSP3_FAIL_WRONG_OCD_STATUS = 0x3D, /* wrong OCD status */
     RSP3_FAIL_NOT_UNDERSTOOD = 0x91,
 
     /* ICE events */
@@ -187,6 +190,7 @@ class jtag3: public jtag
     unsigned long cached_pc;
     bool cached_pc_is_valid;
     bool is_edbg;
+    bool is_capture;
 
     unsigned char flashCache[MAX_FLASH_PAGE_SIZE];
     unsigned int flashCachePageAddr;
@@ -202,7 +206,8 @@ class jtag3: public jtag
     jtag3(const char *dev, char *name, enum debugproto prot = PROTO_JTAG,
 	  bool nsrst = false,
           bool xmega = false,
-          bool edbg = false):
+          bool edbg = false,
+          bool capture = false):
         jtag(dev, name, edbg? EMULATOR_EDBG: EMULATOR_JTAGICE3) {
 	signedIn = debug_active = false;
 	command_sequence = 0;
@@ -220,6 +225,7 @@ class jtag3: public jtag
         device_id = 0;
         cached_event = NULL;
         is_edbg = edbg;
+        is_capture = capture;
     };
     virtual ~jtag3(void);
 
@@ -353,6 +359,8 @@ class jtag3: public jtag
     /** Update Xmega breakpoints on target
      **/
     void xmegaSendBPs(void);
+
+    void attach(void);
 };
 
 class jtag3_io_exception: public jtag_io_exception

src/jtag3io.cc

@@ -56,6 +56,9 @@ jtag3_io_exception::jtag3_io_exception(unsigned int code)
     case RSP3_FAIL_NO_TARGET_POWER:
       reason = "No target power present"; break;
 
+    case RSP3_FAIL_NOT_ATTACHED:
+      reason = "Must run attach command first"; break;
+
     case RSP3_FAIL_WRONG_MODE:
       reason = "wrong mode"; break;
 
@@ -65,6 +68,12 @@ jtag3_io_exception::jtag3_io_exception(unsigned int code)
     case RSP3_FAIL_WRONG_LENGTH:
       reason = "wrong length for memory access"; break;
 
+    case RSP3_FAIL_TIMEOUT:
+      reason = "A timeout occurred"; break;
+
+    case RSP3_FAIL_WRONG_OCD_STATUS:
+      reason = "wrong OCD status (check OCDEN fuse)"; break;
+
     case RSP3_FAIL_NOT_UNDERSTOOD:
       reason = "command not understood"; break;
 
@@ -537,8 +546,6 @@ void jtag3::startJtagLink(void)
       // ignore
     }
   }
-
-  debug_active = true;
 }
 
 /** Device automatic configuration
@@ -651,6 +658,22 @@ void jtag3::deviceAutoConfig(void)
 }
 
 
+// Attach to target and stop program
+void jtag3::attach(void)
+{
+    uchar cmd[] = { SCOPE_AVR, CMD3_START_DEBUG, 0, 1 };
+    uchar *resp;
+    int respsize;
+    bool bp, intr;
+
+    doJtagCommand(cmd, sizeof cmd, "start debugging", resp, respsize);
+    delete [] resp;
+    expectEvent(bp, intr);
+
+    debug_active = true;
+}
+
+
 void jtag3::initJtagBox(void)
 {
     statusOut("JTAG config starting.\n");
@@ -683,6 +706,30 @@ void jtag3::initJtagBox(void)
 
       deviceAutoConfig();
 
+      // Unconditionally try to attach. Some physical interfaces (DebugWire)
+      // implicitly attach, but the EDBG reference implies it's always
+      // necessary.
+      try
+      {
+        attach();
+      }
+      catch (jtag_io_exception& e)
+      {
+        bool bp, intr;
+
+        if (e.get_response() != RSP3_FAIL_WRONG_OCD_STATUS)
+        {
+          throw;
+        }
+        // failed attach can still generate a BREAK
+        expectEvent(bp, intr);
+
+        // If not doing capture, ignore failure, because
+        // initJtagOnChipDebugging might take care of it
+        if (is_capture) {
+          throw;
+        }
+      }
       // Clear out the breakpoints.
       deleteAllBreakpoints();
 
@@ -728,18 +775,16 @@ void jtag3::initJtagOnChipDebugging(unsigned long bitrate)
     // Ensure on-chip debug enable fuse is enabled ie '0'
     jtagActivateOcdenFuse();
 
-    uchar timers = 0;		// stopped
-    setJtagParameter(SCOPE_AVR, 3, PARM3_TIMERS_RUNNING, &timers, 1);
-
-    if (proto == PROTO_DW || is_xmega)
+    if (proto != PROTO_DW && !debug_active)
     {
-        uchar cmd[] = { SCOPE_AVR, CMD3_START_DEBUG, 0, 1 };
-        uchar *resp;
-        int respsize;
-
-        doJtagCommand(cmd, sizeof cmd, "start debugging", resp, respsize);
-        delete [] resp;
+        // Absorb BREAK from leaving progmode
+        bool bp, gdb;
+        expectEvent(bp, gdb);
     }
+    debug_active = true;
+
+    uchar timers = 0;		// stopped
+    setJtagParameter(SCOPE_AVR, 3, PARM3_TIMERS_RUNNING, &timers, 1);
 
     // Sometimes (like, after just enabling the OCDEN fuse), the first
     // resetProgram() runs into an error code 0x32.  Just retry it once.
@@ -749,6 +794,9 @@ void jtag3::initJtagOnChipDebugging(unsigned long bitrate)
       }
     catch (jtag_exception &e)
       {
+	// Absorb BREAK from failed reset
+	bool bp, gdb;
+	expectEvent(bp, gdb);
 	debugOut("retrying reset ...\n");
 	resetProgram();
       }

src/jtag3prog.cc

@@ -53,6 +53,12 @@ void jtag3::disableProgramming(void)
     {
 	programmingEnabled = false;
 	doSimpleJtagCommand(CMD3_LEAVE_PROGMODE, "leave progmode");
+	// Leaving progmode with OCD active can produce a BREAK
+	if (debug_active)
+	{
+	    bool bp, intr;
+	    expectEvent(bp, intr);
+	}
     }
 }
 

src/main.cc

@@ -600,12 +600,12 @@ int main(int argc, char **argv)
 
 	case JTAG3:
 	    theJtagICE = new jtag3(jtagDeviceName, device_name, proto,
-				   apply_nsrst, is_xmega);
+				   apply_nsrst, is_xmega, false, capture);
 	    break;
 
 	case EDBG:
 	    theJtagICE = new jtag3(jtagDeviceName, device_name, proto,
-				   apply_nsrst, is_xmega, true);
+				   apply_nsrst, is_xmega, true, capture);
 	    break;
 	}