arm_jtag_set_instr(jtag_info, instr, NULL);
/* Add specified number of tck clocks before accessing memory bus */
+
+ /* REVISIT these TCK cycles should be *AFTER* updating APACC, since
+ * they provide more time for the (MEM) AP to complete the read ...
+ */
if ((instr == JTAG_DP_APACC)
&& ((reg_addr == AP_REG_DRW)
|| ((reg_addr & 0xF0) == AP_REG_BD0))
arm_jtag_set_instr(jtag_info, instr, NULL);
/* Add specified number of tck clocks before accessing memory bus */
+
+ /* REVISIT these TCK cycles should be *AFTER* updating APACC, since
+ * they provide more time for the (MEM) AP to complete the read ...
+ */
if ((instr == JTAG_DP_APACC)
&& ((reg_addr == AP_REG_DRW)
|| ((reg_addr & 0xF0) == AP_REG_BD0))
uint8_t instr, uint8_t reg_addr, uint8_t RnW,
uint32_t outvalue, uint32_t *invalue)
{
+ /* Issue the read or write */
adi_jtag_dp_scan_u32(swjdp, instr, reg_addr, RnW, outvalue, NULL, NULL);
+ /* For reads, collect posted value; RDBUFF has no other effect.
+ * Assumes read gets acked with OK/FAULT, and CTRL_STAT says "OK".
+ */
if ((RnW == DPAP_READ) && (invalue != NULL))
adi_jtag_dp_scan_u32(swjdp, JTAG_DP_DPACC,
DP_RDBUFF, DPAP_READ, 0, invalue, &swjdp->ack);
/* Why??? second time it works??? */
#endif
+ /* Post CTRL/STAT read; discard any previous posted read value
+ * but collect its ACK status.
+ */
scan_inout_check_u32(swjdp, JTAG_DP_DPACC,
DP_CTRL_STAT, DPAP_READ, 0, &ctrlstat);
if ((retval = jtag_execute_queue()) != ERROR_OK)
swjdp->ack = swjdp->ack & 0x7;
- if (swjdp->ack != 2)
+ /* common code path avoids calling timeval_ms() */
+ if (swjdp->ack != JTAG_ACK_OK_FAULT)
{
long long then = timeval_ms();
- while (swjdp->ack != 2)
+
+ while (swjdp->ack != JTAG_ACK_OK_FAULT)
{
- if (swjdp->ack == 1)
+ if (swjdp->ack == JTAG_ACK_WAIT)
{
if ((timeval_ms()-then) > 1000)
{
return retval;
swjdp->ack = swjdp->ack & 0x7;
}
- } else
- {
- /* common code path avoids fn to timeval_ms() */
}
/* Check for STICKYERR and STICKYORUN */
DPAP_READ, 0, NULL, NULL);
for (readcount = 0; readcount < blocksize - 1; readcount++)
{
- /* Scan out read instruction and scan in previous value */
+ /* Scan out next read; scan in posted value for the
+ * previous one. Assumes read is acked "OK/FAULT",
+ * and CTRL_STAT says that meant "OK".
+ */
adi_jtag_dp_scan(swjdp, JTAG_DP_APACC, AP_REG_DRW,
DPAP_READ, 0, buffer + 4 * readcount,
&swjdp->ack);
}
- /* Scan in last value */
+ /* Scan in last posted value; RDBUFF has no other effect,
+ * assuming ack is OK/FAULT and CTRL_STAT says "OK".
+ */
adi_jtag_dp_scan(swjdp, JTAG_DP_DPACC, DP_RDBUFF,
DPAP_READ, 0, buffer + 4 * readcount,
&swjdp->ack);