More jtag_add_reset() cleanup:
Unify the handling of the req_srst parameter, and rip out a
large NOP branch and its associated FIXME. (There didn't seem
to be anything that needs fixing; but that was unclear since
the constraints were scattered all over the place not unified.)
---
src/jtag/core.c | 59 +++++++++++++++++++++---------------------------------
1 file changed, 23 insertions(+), 36 deletions(-)
--- a/src/jtag/core.c
+++ b/src/jtag/core.c
@@ -594,9 +594,31 @@ void jtag_add_clocks(int num_cycles)
void jtag_add_reset(int req_tlr_or_trst, int req_srst)
{
int trst_with_tlr = 0;
- int new_srst;
+ int new_srst = 0;
int new_trst = 0;
+ /* Without SRST, we must use target-specific JTAG operations
+ * on each target; callers should not be requesting SRST when
+ * that signal doesn't exist.
+ *
+ * RESET_SRST_PULLS_TRST is a board or chip level quirk, which
+ * can kick in even if the JTAG adapter can't drive TRST.
+ */
+ if (req_srst) {
+ if (!(jtag_reset_config & RESET_HAS_SRST)) {
+ LOG_ERROR("BUG: can't assert SRST");
+ jtag_set_error(ERROR_FAIL);
+ return;
+ }
+ if ((jtag_reset_config & RESET_SRST_PULLS_TRST) != 0
+ && !req_tlr_or_trst) {
+ LOG_ERROR("BUG: can't assert only SRST");
+ jtag_set_error(ERROR_FAIL);
+ return;
+ }
+ new_srst = 1;
+ }
+
/* JTAG reset (entry to TAP_RESET state) can always be achieved
* using TCK and TMS; that may go through a TAP_{IR,DR}UPDATE
* state first. TRST accelerates it, and bypasses those states.
@@ -614,41 +636,6 @@ void jtag_add_reset(int req_tlr_or_trst,
new_trst = 1;
}
- /* FIX!!! there are *many* different cases here. A better
- * approach is needed for legal combinations of transitions...
- */
- if ((jtag_reset_config & RESET_HAS_SRST)&&
- (jtag_reset_config & RESET_HAS_TRST)&&
- ((jtag_reset_config & RESET_SRST_PULLS_TRST) == 0))
- {
- if (((req_tlr_or_trst&&!jtag_trst)||
- (!req_tlr_or_trst && jtag_trst))&&
- ((req_srst&&!jtag_srst)||
- (!req_srst && jtag_srst)))
- {
- /* FIX!!! srst_pulls_trst allows 1,1 => 0,0
transition.... */
- //LOG_ERROR("BUG: transition of req_tlr_or_trst and
req_srst in the same jtag_add_reset() call is undefined");
- }
- }
-
- /* 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_tlr_or_trst))
- {
- LOG_ERROR("BUG: requested reset would assert trst");
- jtag_set_error(ERROR_FAIL);
- return;
- }
-
- if (req_srst && !(jtag_reset_config & RESET_HAS_SRST))
- {
- LOG_ERROR("BUG: requested SRST assertion, but the current
configuration doesn't support this");
- jtag_set_error(ERROR_FAIL);
- return;
- }
-
- new_srst = req_srst;
-
/* Maybe change TRST and/or SRST signal state */
if (jtag_srst != new_srst || jtag_trst != new_trst) {
int retval;
More jtag_add_reset() cleanup:
Unify the handling of the req_srst parameter, and rip out a
large NOP branch and its associated FIXME. (There didn't seem
to be anything that needs fixing; but that was unclear since
the constraints were scattered all over the place not unified.)
---
src/jtag/core.c | 59 +++++++++++++++++++++---------------------------------
1 file changed, 23 insertions(+), 36 deletions(-)
--- a/src/jtag/core.c
+++ b/src/jtag/core.c
@@ -594,9 +594,31 @@ void jtag_add_clocks(int num_cycles)
void jtag_add_reset(int req_tlr_or_trst, int req_srst)
{
int trst_with_tlr = 0;
- int new_srst;
+ int new_srst = 0;
int new_trst = 0;
+ /* Without SRST, we must use target-specific JTAG operations
+ * on each target; callers should not be requesting SRST when
+ * that signal doesn't exist.
+ *
+ * RESET_SRST_PULLS_TRST is a board or chip level quirk, which
+ * can kick in even if the JTAG adapter can't drive TRST.
+ */
+ if (req_srst) {
+ if (!(jtag_reset_config & RESET_HAS_SRST)) {
+ LOG_ERROR("BUG: can't assert SRST");
+ jtag_set_error(ERROR_FAIL);
+ return;
+ }
+ if ((jtag_reset_config & RESET_SRST_PULLS_TRST) != 0
+ && !req_tlr_or_trst) {
+ LOG_ERROR("BUG: can't assert only SRST");
+ jtag_set_error(ERROR_FAIL);
+ return;
+ }
+ new_srst = 1;
+ }
+
/* JTAG reset (entry to TAP_RESET state) can always be achieved
* using TCK and TMS; that may go through a TAP_{IR,DR}UPDATE
* state first. TRST accelerates it, and bypasses those states.
@@ -614,41 +636,6 @@ void jtag_add_reset(int req_tlr_or_trst,
new_trst = 1;
}
- /* FIX!!! there are *many* different cases here. A better
- * approach is needed for legal combinations of transitions...
- */
- if ((jtag_reset_config & RESET_HAS_SRST)&&
- (jtag_reset_config & RESET_HAS_TRST)&&
- ((jtag_reset_config & RESET_SRST_PULLS_TRST) == 0))
- {
- if (((req_tlr_or_trst&&!jtag_trst)||
- (!req_tlr_or_trst && jtag_trst))&&
- ((req_srst&&!jtag_srst)||
- (!req_srst && jtag_srst)))
- {
- /* FIX!!! srst_pulls_trst allows 1,1 => 0,0 transition.... */
- //LOG_ERROR("BUG: transition of req_tlr_or_trst and req_srst in the same jtag_add_reset() call is undefined");
- }
- }
-
- /* 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_tlr_or_trst))
- {
- LOG_ERROR("BUG: requested reset would assert trst");
- jtag_set_error(ERROR_FAIL);
- return;
- }
-
- if (req_srst && !(jtag_reset_config & RESET_HAS_SRST))
- {
- LOG_ERROR("BUG: requested SRST assertion, but the current configuration doesn't support this");
- jtag_set_error(ERROR_FAIL);
- return;
- }
-
- new_srst = req_srst;
-
/* Maybe change TRST and/or SRST signal state */
if (jtag_srst != new_srst || jtag_trst != new_trst) {
int retval;
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