transition more directly to the end state + reuse more of the state move code/paths
authoroharboe <oharboe@b42882b7-edfa-0310-969c-e2dbd0fdcd60>
Wed, 6 May 2009 17:25:14 +0000 (17:25 +0000)
committeroharboe <oharboe@b42882b7-edfa-0310-969c-e2dbd0fdcd60>
Wed, 6 May 2009 17:25:14 +0000 (17:25 +0000)
git-svn-id: svn://svn.berlios.de/openocd/trunk@1615 b42882b7-edfa-0310-969c-e2dbd0fdcd60

src/jtag/bitbang.c

index fe5f86c41db8dc79cc90ba21a835da03e1fc077b..ea1f016cacc3f4d4cdbf2606839cb7912c3510b6 100644 (file)
@@ -84,12 +84,12 @@ static void bitbang_end_state(tap_state_t state)
        }
 }
 
-static void bitbang_state_move(void)
+static void bitbang_state_move(int skip)
 {
        int i=0, tms=0;
        u8 tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
 
-       for (i = 0; i < 7; i++)
+       for (i = skip; i < 7; i++)
        {
                tms = (tms_scan >> i) & 1;
                bitbang_interface->write(0, tms, 0);
@@ -146,7 +146,7 @@ static void bitbang_runtest(int num_cycles)
        if (tap_get_state() != TAP_IDLE)
        {
                bitbang_end_state(TAP_IDLE);
-               bitbang_state_move();
+               bitbang_state_move(0);
        }
 
        /* execute num_cycles */
@@ -160,7 +160,7 @@ static void bitbang_runtest(int num_cycles)
        /* finish in end_state */
        bitbang_end_state(saved_end_state);
        if (tap_get_state() != tap_get_end_state())
-               bitbang_state_move();
+               bitbang_state_move(0);
 }
 
 
@@ -191,7 +191,7 @@ static void bitbang_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_
                else
                        bitbang_end_state(TAP_DRSHIFT);
 
-               bitbang_state_move();
+               bitbang_state_move(0);
                bitbang_end_state(saved_end_state);
        }
 
@@ -227,22 +227,14 @@ static void bitbang_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_
                }
        }
 
-       /* TAP_DRSHIFT & TAP_IRSHIFT are illegal end states, so we always transition to the pause
-        * state which is a legal stable state from which statemove will work.
-        *
-        * Exit1 -> Pause
-        */
-       bitbang_interface->write(0, 0, 0);
-       bitbang_interface->write(1, 0, 0);
-       bitbang_interface->write(CLOCK_IDLE(), 0, 0);
-
-       if (ir_scan)
-               tap_set_state(TAP_IRPAUSE);
-       else
-               tap_set_state(TAP_DRPAUSE);
-
        if (tap_get_state() != tap_get_end_state())
-               bitbang_state_move();
+       {
+               /* we *KNOW* the above loop transitioned out of
+                * the shift state, so we skip the first state
+                * and move directly to the end state.
+                */
+               bitbang_state_move(1);
+       }
 }
 
 int bitbang_execute_queue(void)
@@ -310,7 +302,7 @@ int bitbang_execute_queue(void)
 #endif
                                if (cmd->cmd.statemove->end_state != TAP_INVALID)
                                        bitbang_end_state(cmd->cmd.statemove->end_state);
-                               bitbang_state_move();
+                               bitbang_state_move(0);
                                break;
                        case JTAG_PATHMOVE:
 #ifdef _DEBUG_JTAG_IO_