DMI read before asserting ndmreset/haltreq.

In case the target needs a moment to recover from the tap/system reset
that might have been performed earlier.

Change-Id: Ifb899098b37d30ebd9024ebc309abbe53bedd906
Signed-off-by: Tim Newsome <tim@sifive.com>

src/jtag/drivers/ftdi.c

@@ -197,6 +197,8 @@ static int ftdi_set_signal(const struct signal *s, char value)
 	bool data;
 	bool oe;
 
+	LOG_DEBUG_IO("set signal '%s' to '%c'", s->name, value);
+
 	if (s->data_mask == 0 && s->oe_mask == 0) {
 		LOG_ERROR("interface doesn't provide signal '%s'", s->name);
 		return ERROR_FAIL;

src/target/riscv/riscv-013.c

@@ -2814,6 +2814,12 @@ static int assert_reset(struct target *target)
 
 	select_dmi(target);
 
+	/* When we get here, OpenOCD might just have done some reset, which may
+	 * have affected DMI or DM. Read a register just to make sure
+	 * everything's in sync again. */
+	if (dm_read(target, NULL, DM_DMSTATUS) != ERROR_OK)
+		return ERROR_FAIL;
+
 	if (target_has_event_action(target, TARGET_EVENT_RESET_ASSERT)) {
 		/* Run the user-supplied script if there is one. */
 		target_handle_event(target, TARGET_EVENT_RESET_ASSERT);