#include "arm_adi_v5.h"
#include <helper/time_support.h>
-
/* JTAG instructions/registers for JTAG-DP and SWJ-DP */
#define JTAG_DP_ABORT 0x8
#define JTAG_DP_DPACC 0xA
/* too expensive to call keep_alive() here */
-#if 0
- /* Danger!!!! BROKEN!!!! */
- adi_jtag_scan_inout_check_u32(dap, JTAG_DP_DPACC,
- DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
- /* Danger!!!! BROKEN!!!! Why will jtag_execute_queue() fail here????
- R956 introduced the check on return value here and now Michael Schwingen reports
- that this code no longer works....
-
- https://lists.berlios.de/pipermail/openocd-development/2008-September/003107.html
- */
- if ((retval = jtag_execute_queue()) != ERROR_OK)
- {
- LOG_ERROR("BUG: Why does this fail the first time????");
- }
- /* Why??? second time it works??? */
-#endif
+ /* Here be dragons!
+ *
+ * It is easy to be in a JTAG clock range where the target
+ * is not operating in a stable fashion. This happens
+ * for a few reasons:
+ *
+ * - the user may construct a simple test case to try to see
+ * if a higher JTAG clock works to eke out more performance.
+ * This simple case may pass, but more complex situations can
+ * fail.
+ *
+ * - The mostly works JTAG clock rate and the complete failure
+ * JTAG clock rate may be as much as 2-4x apart. This seems
+ * to be especially true on RC oscillator driven parts.
+ *
+ * So: even if calling adi_jtag_scan_inout_check_u32() multiple
+ * times here seems to "make things better here", it is just
+ * hiding problems with too high a JTAG clock.
+ *
+ * Note that even if some parts have RCLK/RTCK, that doesn't
+ * mean that RCLK/RTCK is the *correct* rate to run the JTAG
+ * interface at, i.e. RCLK/RTCK rates can be "too high", especially
+ * before the RC oscillator phase is not yet complete.
+ */
/* Post CTRL/STAT read; discard any previous posted read value
* but collect its ACK status.
DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
if (retval != ERROR_OK)
return retval;
- if ((retval = jtag_execute_queue()) != ERROR_OK)
+ retval = jtag_execute_queue();
+ if (retval != ERROR_OK)
return retval;
dap->ack = dap->ack & 0x7;
/* common code path avoids calling timeval_ms() */
- if (dap->ack != JTAG_ACK_OK_FAULT)
- {
+ if (dap->ack != JTAG_ACK_OK_FAULT) {
long long then = timeval_ms();
- while (dap->ack != JTAG_ACK_OK_FAULT)
- {
- if (dap->ack == JTAG_ACK_WAIT)
- {
- if ((timeval_ms()-then) > 1000)
- {
+ while (dap->ack != JTAG_ACK_OK_FAULT) {
+ if (dap->ack == JTAG_ACK_WAIT) {
+ if ((timeval_ms()-then) > 1000) {
/* NOTE: this would be a good spot
* to use JTAG_DP_ABORT.
*/
"in JTAG-DP transaction");
return ERROR_JTAG_DEVICE_ERROR;
}
- }
- else
- {
+ } else {
LOG_WARNING("Invalid ACK %#x "
"in JTAG-DP transaction",
dap->ack);
DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
if (retval != ERROR_OK)
return retval;
- if ((retval = dap_run(dap)) != ERROR_OK)
+ retval = jtag_execute_queue();
+ if (retval != ERROR_OK)
return retval;
dap->ack = dap->ack & 0x7;
}
/* REVISIT also STICKYCMP, for pushed comparisons (nyet used) */
/* Check for STICKYERR and STICKYORUN */
- if (ctrlstat & (SSTICKYORUN | SSTICKYERR))
- {
+ if (ctrlstat & (SSTICKYORUN | SSTICKYERR)) {
LOG_DEBUG("jtag-dp: CTRL/STAT error, 0x%" PRIx32, ctrlstat);
/* Check power to debug regions */
- if ((ctrlstat & 0xf0000000) != 0xf0000000)
- {
+ if ((ctrlstat & 0xf0000000) != 0xf0000000) {
retval = ahbap_debugport_init(dap);
if (retval != ERROR_OK)
return retval;
- }
- else
- {
+ } else {
uint32_t mem_ap_csw, mem_ap_tar;
/* Maybe print information about last intended
DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
if (retval != ERROR_OK)
return retval;
- if ((retval = dap_run(dap)) != ERROR_OK)
+ retval = jtag_execute_queue();
+ if (retval != ERROR_OK)
return retval;
LOG_DEBUG("jtag-dp: CTRL/STAT 0x%" PRIx32, ctrlstat);
if (retval != ERROR_OK)
return retval;
- if ((retval = dap_run(dap)) != ERROR_OK)
+ retval = jtag_execute_queue();
+ if (retval != ERROR_OK)
return retval;
LOG_ERROR("MEM_AP_CSW 0x%" PRIx32 ", MEM_AP_TAR 0x%"
PRIx32, mem_ap_csw, mem_ap_tar);
}
- if ((retval = dap_run(dap)) != ERROR_OK)
+ retval = jtag_execute_queue();
+ if (retval != ERROR_OK)
return retval;
return ERROR_JTAG_DEVICE_ERROR;
}
return ERROR_OK;
dap->ap_bank_value = select_ap_bank;
- select_ap_bank |= dap->apsel;
+ select_ap_bank |= dap->ap_current;
return jtag_dp_q_write(dap, DP_SELECT, select_ap_bank);
}