make jtag_add_statemove() internal to the driver.

git-svn-id: svn://svn.berlios.de/openocd/trunk@527 b42882b7-edfa-0310-969c-e2dbd0fdcd60

2 files changed, 42 insertions, 56 deletions

diff --git a/src/jtag/jtag.c b/src/jtag/jtag.c
index 8f55ea0b..671c7ac9 100644
--- a/src/jtag/jtag.c
+++ b/src/jtag/jtag.c
@@ -222,7 +222,6 @@ int jtag_speed_post_reset = 0;
 
 
 /* forward declarations */
-void jtag_add_statemove(enum tap_state endstate);
 void jtag_add_pathmove(int num_states, enum tap_state *path);
 void jtag_add_runtest(int num_cycles, enum tap_state endstate);
 void jtag_add_reset(int trst, int srst);
@@ -245,7 +244,6 @@ int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char
 int handle_endstate_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 int handle_jtag_reset_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 int handle_runtest_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
-int handle_statemove_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 int handle_drscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
 
@@ -777,18 +775,20 @@ int MINIDRIVER(interface_jtag_add_plain_dr_scan)(int num_fields, scan_field_t *f
 
 	return ERROR_OK;
 }
-void jtag_add_statemove(enum tap_state state)
-{
-	jtag_prelude(state);
 
+void jtag_add_tms()
+{
+	jtag_prelude(TAP_TLR);
+	
 	int retval;
-	retval=interface_jtag_add_statemove(cmd_queue_end_state);
+	retval=interface_jtag_add_tms();
 	if (retval!=ERROR_OK)
 		jtag_error=retval;
 }
 
-int MINIDRIVER(interface_jtag_add_statemove)(enum tap_state state)
+int MINIDRIVER(interface_jtag_add_tms)()
 {
+	enum tap_state state = TAP_TLR;
 	jtag_command_t **last_cmd = jtag_get_last_command_p();
 	
 	/* allocate memory for a new list member */
@@ -943,7 +943,7 @@ void jtag_add_reset(int req_trst, int req_srst)
 	{
 		LOG_DEBUG("JTAG reset with tms instead of TRST");
 		jtag_add_end_state(TAP_TLR);
-		jtag_add_statemove(TAP_TLR);
+		jtag_add_tms();
 		jtag_call_event_callbacks(JTAG_TRST_ASSERTED);
 		return;
 	}
@@ -1429,8 +1429,6 @@ int jtag_register_commands(struct command_context_s *cmd_ctx)
 		COMMAND_EXEC, "toggle reset lines <trst> <srst>");
 	register_command(cmd_ctx, NULL, "runtest", handle_runtest_command,
 		COMMAND_EXEC, "move to Run-Test/Idle, and execute <num_cycles>");
-	register_command(cmd_ctx, NULL, "statemove", handle_statemove_command,
-		COMMAND_EXEC, "move to current endstate or [tap_state]");
 	register_command(cmd_ctx, NULL, "irscan", handle_irscan_command,
 		COMMAND_EXEC, "execute IR scan <device> <instr> [dev2] [instr2] ...");
 	register_command(cmd_ctx, NULL, "drscan", handle_drscan_command,
@@ -1477,7 +1475,7 @@ int jtag_init(struct command_context_s *cmd_ctx)
 		device = device->next;
 	}
 	
-	jtag_add_statemove(TAP_TLR);
+	jtag_add_tms();
 	jtag_execute_queue();
 
 	/* examine chain first, as this could discover the real chain layout */
@@ -1837,28 +1835,6 @@ int handle_runtest_command(struct command_context_s *cmd_ctx, char *cmd, char **
 
 }
 
-int handle_statemove_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
-{
-	enum tap_state state;
-
-	state = -1;
-	if (argc == 1)
-	{
-		for (state = 0; state < 16; state++)
-		{
-			if (strcmp(args[0], tap_state_strings[state]) == 0)
-			{
-				break;
-			}
-		}
-	}
-
-	jtag_add_statemove(state);
-	jtag_execute_queue();
-
-	return ERROR_OK;
-
-}
 
 int handle_irscan_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
diff --git a/src/jtag/jtag.h b/src/jtag/jtag.h
index 4d482f06..2c186e9c 100644
--- a/src/jtag/jtag.h
+++ b/src/jtag/jtag.h
@@ -248,7 +248,14 @@ extern int jtag_register_commands(struct command_context_s *cmd_ctx);
 /* JTAG interface, can be implemented with a software or hardware fifo
  * 
  * TAP_SD and TAP_SI are illegal end states. TAP_SD/SI as end states
- * can be emulated by using a larger scan. 
+ * can be emulated by using a larger scan.
+ *
+ * Code that is relatively insensitive to the path(as long
+ * as it is JTAG compliant) taken through state machine can use 
+ * endstate for jtag_add_xxx_scan(). Otherwise the pause state must be 
+ * specified as end state and a subsequent jtag_add_pathmove() must 
+ * be issued. 
+ *
  */
 extern void jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
 extern int interface_jtag_add_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
@@ -258,30 +265,24 @@ extern void jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum ta
 extern int interface_jtag_add_plain_ir_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
 extern void jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
 extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields, enum tap_state endstate);
-/* execute a state transition within the JTAG standard, but the exact path
- * path that is taken is undefined. Many implementations use precisely
- * 7 clocks to perform a transition, but it could be more or less
- * than that.
- *
- * The following assertions are made about certain common state moves:
- *
- * - A state move from Pause-[ID]R to Pause-[ID]R should always go through 
- *   Update-[ID]R and Capture-[ID]R before returning to Pause-[ID]R, otherwise 
- *   there's no way force a register update, if you can't go to Run-Test/Idle for 
- *   some reason.
+/* run a TAP_TLR reset. End state is TAP_TLR, regardless
+ * of start state.
+ */
+extern void jtag_add_tms();
+extern int interface_jtag_add_tms();
+/* Do not use jtag_add_pathmove() unless you need to, but do use it
+ * if you have to. 
  *
- *   - A state move from Pause-[ID]R to Shift-[ID]R must not go through 
- *   Update-[ID]R.
+ * DANGER! If the target is dependent upon a particular sequence
+ * of transitions for things to work correctly(e.g. as a workaround 
+ * for an errata that contradicts the JTAG standard), then pathmove 
+ * must be used, even if some jtag interfaces happen to use the 
+ * desired path. Worse, the jtag interface used for testing a 
+ * particular implementation, could happen to use the "desired" 
+ * path when transitioning to/from end
+ * state.
  *
- *   - Run-Test/Idle must not be entered unless requested, because R-T/I may have 
- *   side effects.
- * 
- * NB! a jtag_add_statemove() to the current state is not
- * a no-operation.
- */
-extern void jtag_add_statemove(enum tap_state endstate);
-extern int interface_jtag_add_statemove(enum tap_state endstate);
-/* A list of unambigious single clock state transitions, not
+ * A list of unambigious single clock state transitions, not
  * all drivers can support this, but it is required for e.g.
  * XScale and Xilinx support
  * 
@@ -289,6 +290,15 @@ extern int interface_jtag_add_statemove(enum tap_state endstate);
  * 
  * Note that the first on the list must be reachable 
  * via a single transition from the current state. 
+ *
+ * All drivers are required to implement jtag_add_pathmove().
+ * However, if the pathmove sequence can not be precisely
+ * executed, an interface_jtag_add_pathmove() or jtag_execute_queue()
+ * must return an error. It is legal, but not recommended, that
+ * a driver returns an error in all cases for a pathmove if it
+ * can only implement a few transitions and therefore
+ * a partial implementation of pathmove would have little practical
+ * application.
  */
 extern void jtag_add_pathmove(int num_states, enum tap_state *path);
 extern int interface_jtag_add_pathmove(int num_states, enum tap_state *path);