/* forward declarations */
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);
void jtag_add_end_state(enum tap_state endstate);
void jtag_add_sleep(u32 us);
int jtag_execute_queue(void);
jtag_error=retval;
}
-void jtag_add_reset(int req_trst, int req_srst)
+void jtag_add_reset(int req_tms_or_trst, int req_srst)
{
int trst_with_tms = 0;
int retval;
/* Make sure that jtag_reset_config allows the requested reset */
/* if SRST pulls TRST, we can't fulfill srst == 1 with trst == 0 */
- if (((jtag_reset_config & RESET_SRST_PULLS_TRST) && (req_srst == 1)) && (req_trst == 0))
+ if (((jtag_reset_config & RESET_SRST_PULLS_TRST) && (req_srst == 1)) && (!req_tms_or_trst))
{
LOG_ERROR("BUG: requested reset would assert trst");
jtag_error=ERROR_FAIL;
}
/* if TRST pulls SRST, we reset with TAP T-L-R */
- if (((jtag_reset_config & RESET_TRST_PULLS_SRST) && (req_trst == 1)) && (req_srst == 0))
+ if (((jtag_reset_config & RESET_TRST_PULLS_SRST) && (req_tms_or_trst)) && (req_srst == 0))
{
- req_trst = 0;
trst_with_tms = 1;
}
if (req_srst && !(jtag_reset_config & RESET_HAS_SRST))
{
- LOG_ERROR("BUG: requested nSRST assertion, but the current configuration doesn't support this");
+ LOG_ERROR("BUG: requested SRST assertion, but the current configuration doesn't support this");
jtag_error=ERROR_FAIL;
return;
}
- if (req_trst && !(jtag_reset_config & RESET_HAS_TRST))
+ if (req_tms_or_trst)
{
- req_trst = 0;
- trst_with_tms = 1;
+ if (!trst_with_tms && (jtag_reset_config & RESET_HAS_TRST))
+ {
+ jtag_trst = 1;
+ } else
+ {
+ trst_with_tms = 1;
+ }
+ } else
+ {
+ jtag_trst = 0;
}
-
- jtag_trst = req_trst;
+
jtag_srst = req_srst;
- retval = interface_jtag_add_reset(req_trst, req_srst);
+ retval = interface_jtag_add_reset(jtag_trst, jtag_srst);
if (retval!=ERROR_OK)
{
jtag_error=retval;
}
else
{
- /* the nTRST line got deasserted, so we're still in Test-Logic-Reset,
- * but we might want to add a delay to give the TAP time to settle
- */
- LOG_DEBUG("Now in TAP_TLR - Test-Logic-Reset(either due to TRST line asserted or tms reset)");
if (jtag_ntrst_delay)
jtag_add_sleep(jtag_ntrst_delay * 1000);
}
int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
{
+ if (argc < 1)
+ return ERROR_COMMAND_SYNTAX_ERROR;
+
if (argc >= 1)
{
if (strcmp(args[0], "none") == 0)
if (argc >= 2)
{
- if (strcmp(args[1], "srst_pulls_trst") == 0)
- jtag_reset_config |= RESET_SRST_PULLS_TRST;
- else if (strcmp(args[1], "trst_pulls_srst") == 0)
- jtag_reset_config |= RESET_TRST_PULLS_SRST;
- else if (strcmp(args[1], "combined") == 0)
- jtag_reset_config |= RESET_SRST_PULLS_TRST | RESET_TRST_PULLS_SRST;
- else if (strcmp(args[1], "separate") == 0)
- jtag_reset_config &= ~(RESET_SRST_PULLS_TRST | RESET_TRST_PULLS_SRST);
- else
+ if (strcmp(args[1], "separate") == 0)
{
- LOG_ERROR("invalid reset_config argument, defaulting to none");
- jtag_reset_config = RESET_NONE;
- return ERROR_INVALID_ARGUMENTS;
+ /* seperate reset lines - default */
+ } else
+ {
+ if (strcmp(args[1], "srst_pulls_trst") == 0)
+ jtag_reset_config |= RESET_SRST_PULLS_TRST;
+ else if (strcmp(args[1], "trst_pulls_srst") == 0)
+ jtag_reset_config |= RESET_TRST_PULLS_SRST;
+ else if (strcmp(args[1], "combined") == 0)
+ jtag_reset_config |= RESET_SRST_PULLS_TRST | RESET_TRST_PULLS_SRST;
+ else
+ {
+ LOG_ERROR("invalid reset_config argument, defaulting to none");
+ jtag_reset_config = RESET_NONE;
+ return ERROR_INVALID_ARGUMENTS;
+ }
}
}
*/
extern void jtag_add_runtest(int num_cycles, enum tap_state endstate);
extern int interface_jtag_add_runtest(int num_cycles, enum tap_state endstate);
-/* Invoking jtag_add_reset() with unsupported combinations is
- * not allowed and constitutes a bug in the calling code.
+/* A reset of the TAP state machine can be requested.
*
- * trst & srst must be 0 or 1. There is no way to
- * read the current reset state.
+ * Whether tms or trst reset is used depends on the capabilities of
+ * the target and jtag interface(reset_config command configures this).
+ *
+ * srst can driver a reset of the TAP state machine and vice
+ * versa
+ *
+ * Application code may need to examine value of jtag_reset_config
+ * to determine the proper codepath
+ *
+ * DANGER! Even though srst drives trst, trst might not be connected to
+ * the interface, and it might actually be *harmful* to assert trst in this case.
+ *
+ * This is why combinations such as "reset_config srst_only srst_pulls_trst"
+ * are supported.
+ *
+ */
+extern void jtag_add_reset(int req_tms_or_trst, int srst);
+/* this drives the actual srst and trst pins. srst will always be 0
+ * if jtag_reset_config & RESET_SRST_PULLS_TRST != 0 and ditto for
+ * trst.
+ *
+ * the higher level jtag_add_reset will invoke jtag_add_tms() if
+ * approperiate
*/
-extern void jtag_add_reset(int trst, int srst);
extern int interface_jtag_add_reset(int trst, int srst);
extern void jtag_add_end_state(enum tap_state endstate);
extern int interface_jtag_add_end_state(enum tap_state endstate);