comment.

[openocd.git] / src / jtag / jtag.h

diff --git a/src/jtag/jtag.h b/src/jtag/jtag.h
index f5602f1f87b6815c95fcf51c378b0cc177fe183c..df1ca08acf836902fb5d9aa27af864757c4b77fa 100644 (file)
--- a/src/jtag/jtag.h
+++ b/src/jtag/jtag.h
@@ -270,6 +270,9 @@ extern int interface_jtag_add_plain_dr_scan(int num_fields, scan_field_t *fields
  *
  *   - 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 int jtag_add_statemove(enum tap_state endstate);
 extern int interface_jtag_add_statemove(enum tap_state endstate);
@@ -278,10 +281,16 @@ extern int interface_jtag_add_statemove(enum tap_state endstate);
  * XScale and Xilinx support
  * 
  * Note! TAP_TLR must not be used in the path!
+ * 
+ * Note that the first on the list must be reachable 
+ * via a single transition from the current state. 
  */
 extern int jtag_add_pathmove(int num_states, enum tap_state *path);
 extern int interface_jtag_add_pathmove(int num_states, enum tap_state *path);
-/* cycle precisely num_cycles in the TAP_RTI state */
+/* go to TAP_RTI, if we're not already there and cycle
+ * precisely num_cycles in the TAP_RTI after which move
+ * to the end state, if it is != TAP_RTI
+ */
 extern int jtag_add_runtest(int num_cycles, enum tap_state endstate);
 extern int interface_jtag_add_runtest(int num_cycles, enum tap_state endstate);
 extern int jtag_add_reset(int trst, int srst);
@@ -344,29 +353,51 @@ extern int jtag_verify_capture_ir;
 #define ERROR_JTAG_DEVICE_ERROR                        (-107)
 
 
-/* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_shift can be defined */
 
-#ifndef MINIDRIVER 
-extern int interface_jtag_add_shift(const enum tap_state shift_state, const enum tap_state end_state, int bits, u32 value);
-#endif
-
-/* Enter the shift_state and cycle "bits" times out of that state.
+/* this allows JTAG devices to implement the entire jtag_xxx() layer in hw/sw */
+#ifdef HAVE_JTAG_MINIDRIVER_H
+/* Here a #define MINIDRIVER() and an inline version of hw fifo interface_jtag_add_dr_out can be defined */
+#include "jtag_minidriver.h"
+#define MINIDRIVER(a) notused ## a 
+#else
+#define MINIDRIVER(a) a
+/* jtag_add_dr_out() is a faster version of jtag_add_dr_scan() 
+ * 
+ * Current or end_state can not be TAP_TLR. end_state can be -1
  * 
- * So if the end_state!=shift_state, then the transition from shift_state to 
- * end_state counts as a transition out of shift_state.
+ * num_bits[i] is the number of bits to clock out from value[i] LSB first.
  * 
- * Legal shift states TAP_SD and TAP_SI
+ * If the device is in bypass, then that is an error condition in
+ * the caller code that is not detected by this fn, whereas jtag_add_dr_scan()
+ * does detect it. Similarly if the device is not in bypass, data must
+ * be passed to it. 
  * 
- * Legal end state does not include TAP_TLR
+ * If anything fails, then jtag_error will be set and jtag_execute() will
+ * return an error. There is no way to determine if there was a failure
+ * during this function call.
  * 
- * Bits are clocked out from value LSB first.
+ * Note that this jtag_add_dr_out can be defined as an inline function.
  */
-static __inline int jtag_add_shift(const enum tap_state shift_state, const enum tap_state end_state, int bits, u32 value)
+extern void interface_jtag_add_dr_out(int device, 
+               int num_fields,
+               int *num_bits,
+               u32 *value,
+               enum tap_state end_state);
+#endif
+
+
+
+
+static __inline__ void jtag_add_dr_out(int device, 
+               int num_fields,
+               int *num_bits,
+               u32 *value,
+               enum tap_state end_state)
 {
-       int retval;
-       retval=interface_jtag_add_shift(shift_state, end_state, bits, value);
-       cmd_queue_end_state = end_state;
-       return retval;
+       if (end_state != -1)
+               cmd_queue_end_state=end_state;
+       cmd_queue_cur_state=cmd_queue_end_state;
+       interface_jtag_add_dr_out(device, num_fields, num_bits, value, cmd_queue_end_state);
 }