diff --git a/src/jtag/bitbang.c b/src/jtag/bitbang.c
index a4e415c2ec8cff69c5de240ddffe67575bb629d9..16b5f1918b3fe6f317d3234b8d2c6fe4cc9a92ab 100644
--- a/src/jtag/bitbang.c
+++ b/src/jtag/bitbang.c
@@ -239,7 +239,7 @@ int bitbang_execute_queue(void)
#ifdef _DEBUG_JTAG_IO_
LOG_DEBUG("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
#endif
- if (cmd->cmd.reset->trst == 1)
+ if ((cmd->cmd.reset->trst == 1) || (cmd->cmd.reset->srst && (jtag_reset_config & RESET_SRST_PULLS_TRST)))
{
cur_state = TAP_TLR;
}
diff --git a/src/jtag/ft2232.c b/src/jtag/ft2232.c
index 747a383a9ea250eecb38b5ecd1db9c9a446a982c..20824bbbd51e1675f25d3ed3c8bc3cbbfffae125 100644
--- a/src/jtag/ft2232.c
+++ b/src/jtag/ft2232.c
@@ -889,7 +889,6 @@ void usbjtag_reset(int trst, int srst)
{
if (trst == 1)
{
- cur_state = TAP_TLR;
if (jtag_reset_config & RESET_TRST_OPEN_DRAIN)
low_direction |= nTRSTnOE; /* switch to output pin (output is low) */
else
@@ -929,7 +928,6 @@ void jtagkey_reset(int trst, int srst)
{
if (trst == 1)
{
- cur_state = TAP_TLR;
if (jtag_reset_config & RESET_TRST_OPEN_DRAIN)
high_output &= ~nTRSTnOE;
else
@@ -969,7 +967,6 @@ void olimex_jtag_reset(int trst, int srst)
{
if (trst == 1)
{
- cur_state = TAP_TLR;
if (jtag_reset_config & RESET_TRST_OPEN_DRAIN)
high_output &= ~nTRSTnOE;
else
@@ -1003,7 +1000,6 @@ void flyswatter_reset(int trst, int srst)
{
if (trst == 1)
{
- cur_state = TAP_TLR;
low_output &= ~nTRST;
}
else if (trst == 0)
@@ -1051,7 +1047,6 @@ void comstick_reset(int trst, int srst)
{
if (trst == 1)
{
- cur_state = TAP_TLR;
high_output &= ~nTRST;
}
else if (trst == 0)
@@ -1079,7 +1074,6 @@ void stm32stick_reset(int trst, int srst)
{
if (trst == 1)
{
- cur_state = TAP_TLR;
high_output &= ~nTRST;
}
else if (trst == 0)
@@ -1151,6 +1145,10 @@ int ft2232_execute_queue()
first_unsent = cmd;
}
+ if ((cmd->cmd.reset->trst == 1) || (cmd->cmd.reset->srst && (jtag_reset_config & RESET_SRST_PULLS_TRST)))
+ {
+ cur_state = TAP_TLR;
+ }
layout->reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
require_send = 1;
diff --git a/src/jtag/jtag.c b/src/jtag/jtag.c
index 671c7ac97cb4d4e54b2e5ce53489fa4635d1657b..34147651ada25916192fb48ae874c92721561b9f 100644
--- a/src/jtag/jtag.c
+++ b/src/jtag/jtag.c
@@ -224,7 +224,6 @@ int jtag_speed_post_reset = 0;
/* 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);
@@ -884,14 +883,14 @@ void jtag_add_runtest(int num_cycles, enum tap_state state)
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;
@@ -899,29 +898,35 @@ void jtag_add_reset(int req_trst, int req_srst)
}
/* 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;
@@ -959,10 +964,6 @@ void jtag_add_reset(int req_trst, int req_srst)
}
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);
}
@@ -1608,6 +1609,9 @@ int handle_scan_chain_command(struct command_context_s *cmd_ctx, char *cmd, char
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)
@@ -1628,19 +1632,23 @@ int handle_reset_config_command(struct command_context_s *cmd_ctx, char *cmd, ch
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;
+ }
}
}
diff --git a/src/jtag/jtag.h b/src/jtag/jtag.h
index 2c186e9cbc3b028a4543a41ae9a2d49d8a15f2d0..114e6aa360b3edd59a1b52d28dd28f212c8b119b 100644
--- a/src/jtag/jtag.h
+++ b/src/jtag/jtag.h
@@ -308,13 +308,32 @@ extern int interface_jtag_add_pathmove(int num_states, enum tap_state *path);
*/
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);