+// SPDX-License-Identifier: GPL-2.0-or-later
+
/***************************************************************************
* Copyright (C) 2005 by Dominic Rath *
* Dominic.Rath@gmx.de *
* *
* Copyright (C) 2007,2008 Øyvind Harboe *
* oyvind.harboe@zylin.com *
- * *
- * This program is free software; you can redistribute it and/or modify *
- * it under the terms of the GNU General Public License as published by *
- * the Free Software Foundation; either version 2 of the License, or *
- * (at your option) any later version. *
- * *
- * This program is distributed in the hope that it will be useful, *
- * but WITHOUT ANY WARRANTY; without even the implied warranty of *
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
- * GNU General Public License for more details. *
- * *
- * You should have received a copy of the GNU General Public License *
- * along with this program. If not, see <http://www.gnu.org/licenses/>. *
***************************************************************************/
/* 2014-12: Addition of the SWD protocol support is based on the initial work
#include "config.h"
#endif
+#include <jtag/jtag.h> /* Added to avoid include loop in commands.h */
#include "bitbang.h"
#include <jtag/interface.h>
#include <jtag/commands.h>
-/* YUK! - but this is currently a global.... */
-extern struct jtag_interface *jtag_interface;
+#include <helper/time_support.h>
+
+/* Timeout for retrying on SWD WAIT in msec */
+#define SWD_WAIT_TIMEOUT 500
/**
* Function bitbang_stableclocks
* this function checks the current stable state to decide on the value of TMS
* to use.
*/
-static void bitbang_stableclocks(int num_cycles);
+static int bitbang_stableclocks(int num_cycles);
static void bitbang_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay_clk);
/* The bitbang driver leaves the TCK 0 when in idle */
static void bitbang_end_state(tap_state_t state)
{
- if (tap_is_state_stable(state))
- tap_set_end_state(state);
- else {
- LOG_ERROR("BUG: %i is not a valid end state", state);
- exit(-1);
- }
+ assert(tap_is_state_stable(state));
+ tap_set_end_state(state);
}
-static void bitbang_state_move(int skip)
+static int bitbang_state_move(int skip)
{
int i = 0, tms = 0;
uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
for (i = skip; i < tms_count; i++) {
tms = (tms_scan >> i) & 1;
- bitbang_interface->write(0, tms, 0);
- bitbang_interface->write(1, tms, 0);
+ if (bitbang_interface->write(0, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
+ if (bitbang_interface->write(1, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
}
- bitbang_interface->write(CLOCK_IDLE(), tms, 0);
+ if (bitbang_interface->write(CLOCK_IDLE(), tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
tap_set_state(tap_get_end_state());
+ return ERROR_OK;
}
/**
unsigned num_bits = cmd->cmd.tms->num_bits;
const uint8_t *bits = cmd->cmd.tms->bits;
- DEBUG_JTAG_IO("TMS: %d bits", num_bits);
+ LOG_DEBUG_IO("TMS: %d bits", num_bits);
int tms = 0;
for (unsigned i = 0; i < num_bits; i++) {
tms = ((bits[i/8] >> (i % 8)) & 1);
- bitbang_interface->write(0, tms, 0);
- bitbang_interface->write(1, tms, 0);
+ if (bitbang_interface->write(0, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
+ if (bitbang_interface->write(1, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
}
- bitbang_interface->write(CLOCK_IDLE(), tms, 0);
+ if (bitbang_interface->write(CLOCK_IDLE(), tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
return ERROR_OK;
}
-static void bitbang_path_move(struct pathmove_command *cmd)
+static int bitbang_path_move(struct pathmove_command *cmd)
{
int num_states = cmd->num_states;
int state_count;
exit(-1);
}
- bitbang_interface->write(0, tms, 0);
- bitbang_interface->write(1, tms, 0);
+ if (bitbang_interface->write(0, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
+ if (bitbang_interface->write(1, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
tap_set_state(cmd->path[state_count]);
state_count++;
num_states--;
}
- bitbang_interface->write(CLOCK_IDLE(), tms, 0);
+ if (bitbang_interface->write(CLOCK_IDLE(), tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
tap_set_end_state(tap_get_state());
+ return ERROR_OK;
}
-static void bitbang_runtest(int num_cycles)
+static int bitbang_runtest(int num_cycles)
{
int i;
/* only do a state_move when we're not already in IDLE */
if (tap_get_state() != TAP_IDLE) {
bitbang_end_state(TAP_IDLE);
- bitbang_state_move(0);
+ if (bitbang_state_move(0) != ERROR_OK)
+ return ERROR_FAIL;
}
/* execute num_cycles */
for (i = 0; i < num_cycles; i++) {
- bitbang_interface->write(0, 0, 0);
- bitbang_interface->write(1, 0, 0);
+ if (bitbang_interface->write(0, 0, 0) != ERROR_OK)
+ return ERROR_FAIL;
+ if (bitbang_interface->write(1, 0, 0) != ERROR_OK)
+ return ERROR_FAIL;
}
- bitbang_interface->write(CLOCK_IDLE(), 0, 0);
+ if (bitbang_interface->write(CLOCK_IDLE(), 0, 0) != ERROR_OK)
+ return ERROR_FAIL;
/* finish in end_state */
bitbang_end_state(saved_end_state);
if (tap_get_state() != tap_get_end_state())
- bitbang_state_move(0);
+ if (bitbang_state_move(0) != ERROR_OK)
+ return ERROR_FAIL;
+
+ return ERROR_OK;
}
-static void bitbang_stableclocks(int num_cycles)
+static int bitbang_stableclocks(int num_cycles)
{
int tms = (tap_get_state() == TAP_RESET ? 1 : 0);
int i;
/* send num_cycles clocks onto the cable */
for (i = 0; i < num_cycles; i++) {
- bitbang_interface->write(1, tms, 0);
- bitbang_interface->write(0, tms, 0);
+ if (bitbang_interface->write(1, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
+ if (bitbang_interface->write(0, tms, 0) != ERROR_OK)
+ return ERROR_FAIL;
}
+
+ return ERROR_OK;
}
-static void bitbang_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size)
+static int bitbang_scan(bool ir_scan, enum scan_type type, uint8_t *buffer,
+ unsigned scan_size)
{
tap_state_t saved_end_state = tap_get_end_state();
- int bit_cnt;
+ unsigned bit_cnt;
if (!((!ir_scan &&
(tap_get_state() == TAP_DRSHIFT)) ||
else
bitbang_end_state(TAP_DRSHIFT);
- bitbang_state_move(0);
+ if (bitbang_state_move(0) != ERROR_OK)
+ return ERROR_FAIL;
bitbang_end_state(saved_end_state);
}
+ size_t buffered = 0;
for (bit_cnt = 0; bit_cnt < scan_size; bit_cnt++) {
- int val = 0;
int tms = (bit_cnt == scan_size-1) ? 1 : 0;
int tdi;
int bytec = bit_cnt/8;
if ((type != SCAN_IN) && (buffer[bytec] & bcval))
tdi = 1;
- bitbang_interface->write(0, tms, tdi);
-
- if (type != SCAN_OUT)
- val = bitbang_interface->read();
-
- bitbang_interface->write(1, tms, tdi);
+ if (bitbang_interface->write(0, tms, tdi) != ERROR_OK)
+ return ERROR_FAIL;
if (type != SCAN_OUT) {
- if (val)
- buffer[bytec] |= bcval;
- else
- buffer[bytec] &= ~bcval;
+ if (bitbang_interface->buf_size) {
+ if (bitbang_interface->sample() != ERROR_OK)
+ return ERROR_FAIL;
+ buffered++;
+ } else {
+ switch (bitbang_interface->read()) {
+ case BB_LOW:
+ buffer[bytec] &= ~bcval;
+ break;
+ case BB_HIGH:
+ buffer[bytec] |= bcval;
+ break;
+ default:
+ return ERROR_FAIL;
+ }
+ }
+ }
+
+ if (bitbang_interface->write(1, tms, tdi) != ERROR_OK)
+ return ERROR_FAIL;
+
+ if (type != SCAN_OUT && bitbang_interface->buf_size &&
+ (buffered == bitbang_interface->buf_size ||
+ bit_cnt == scan_size - 1)) {
+ for (unsigned i = bit_cnt + 1 - buffered; i <= bit_cnt; i++) {
+ switch (bitbang_interface->read_sample()) {
+ case BB_LOW:
+ buffer[i/8] &= ~(1 << (i % 8));
+ break;
+ case BB_HIGH:
+ buffer[i/8] |= 1 << (i % 8);
+ break;
+ default:
+ return ERROR_FAIL;
+ }
+ }
+ buffered = 0;
}
}
* the shift state, so we skip the first state
* and move directly to the end state.
*/
- bitbang_state_move(1);
+ if (bitbang_state_move(1) != ERROR_OK)
+ return ERROR_FAIL;
+ }
+ return ERROR_OK;
+}
+
+static void bitbang_sleep(unsigned int microseconds)
+{
+ if (bitbang_interface->sleep) {
+ bitbang_interface->sleep(microseconds);
+ } else {
+ jtag_sleep(microseconds);
}
}
-int bitbang_execute_queue(void)
+int bitbang_execute_queue(struct jtag_command *cmd_queue)
{
- struct jtag_command *cmd = jtag_command_queue; /* currently processed command */
+ struct jtag_command *cmd = cmd_queue; /* currently processed command */
int scan_size;
enum scan_type type;
uint8_t *buffer;
*/
retval = ERROR_OK;
- if (bitbang_interface->blink)
- bitbang_interface->blink(1);
+ if (bitbang_interface->blink) {
+ if (bitbang_interface->blink(1) != ERROR_OK)
+ return ERROR_FAIL;
+ }
while (cmd) {
switch (cmd->type) {
- case JTAG_RESET:
-#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) ||
- (cmd->cmd.reset->srst && (jtag_get_reset_config() & RESET_SRST_PULLS_TRST)))
- tap_set_state(TAP_RESET);
- bitbang_interface->reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
- break;
case JTAG_RUNTEST:
-#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("runtest %i cycles, end in %s",
+ LOG_DEBUG_IO("runtest %i cycles, end in %s",
cmd->cmd.runtest->num_cycles,
tap_state_name(cmd->cmd.runtest->end_state));
-#endif
bitbang_end_state(cmd->cmd.runtest->end_state);
- bitbang_runtest(cmd->cmd.runtest->num_cycles);
+ if (bitbang_runtest(cmd->cmd.runtest->num_cycles) != ERROR_OK)
+ return ERROR_FAIL;
break;
case JTAG_STABLECLOCKS:
/* this is only allowed while in a stable state. A check for a stable
* state was done in jtag_add_clocks()
*/
- bitbang_stableclocks(cmd->cmd.stableclocks->num_cycles);
+ if (bitbang_stableclocks(cmd->cmd.stableclocks->num_cycles) != ERROR_OK)
+ return ERROR_FAIL;
break;
case JTAG_TLR_RESET:
-#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("statemove end in %s",
+ LOG_DEBUG_IO("statemove end in %s",
tap_state_name(cmd->cmd.statemove->end_state));
-#endif
bitbang_end_state(cmd->cmd.statemove->end_state);
- bitbang_state_move(0);
+ if (bitbang_state_move(0) != ERROR_OK)
+ return ERROR_FAIL;
break;
case JTAG_PATHMOVE:
-#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("pathmove: %i states, end in %s",
+ LOG_DEBUG_IO("pathmove: %i states, end in %s",
cmd->cmd.pathmove->num_states,
tap_state_name(cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]));
-#endif
- bitbang_path_move(cmd->cmd.pathmove);
+ if (bitbang_path_move(cmd->cmd.pathmove) != ERROR_OK)
+ return ERROR_FAIL;
break;
case JTAG_SCAN:
-#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("%s scan end in %s",
- (cmd->cmd.scan->ir_scan) ? "IR" : "DR",
- tap_state_name(cmd->cmd.scan->end_state));
-#endif
bitbang_end_state(cmd->cmd.scan->end_state);
scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
+ LOG_DEBUG_IO("%s scan %d bits; end in %s",
+ (cmd->cmd.scan->ir_scan) ? "IR" : "DR",
+ scan_size,
+ tap_state_name(cmd->cmd.scan->end_state));
type = jtag_scan_type(cmd->cmd.scan);
- bitbang_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size);
+ if (bitbang_scan(cmd->cmd.scan->ir_scan, type, buffer,
+ scan_size) != ERROR_OK)
+ return ERROR_FAIL;
if (jtag_read_buffer(buffer, cmd->cmd.scan) != ERROR_OK)
retval = ERROR_JTAG_QUEUE_FAILED;
- if (buffer)
- free(buffer);
+ free(buffer);
break;
case JTAG_SLEEP:
-#ifdef _DEBUG_JTAG_IO_
- LOG_DEBUG("sleep %" PRIi32, cmd->cmd.sleep->us);
-#endif
- jtag_sleep(cmd->cmd.sleep->us);
+ LOG_DEBUG_IO("sleep %" PRIu32, cmd->cmd.sleep->us);
+ if (bitbang_interface->flush && (bitbang_interface->flush() != ERROR_OK))
+ return ERROR_FAIL;
+ bitbang_sleep(cmd->cmd.sleep->us);
break;
case JTAG_TMS:
retval = bitbang_execute_tms(cmd);
}
cmd = cmd->next;
}
- if (bitbang_interface->blink)
- bitbang_interface->blink(0);
+ if (bitbang_interface->blink) {
+ if (bitbang_interface->blink(0) != ERROR_OK)
+ return ERROR_FAIL;
+ }
return retval;
}
-
-bool swd_mode;
static int queued_retval;
static int bitbang_swd_init(void)
{
LOG_DEBUG("bitbang_swd_init");
- swd_mode = true;
return ERROR_OK;
}
-static void bitbang_exchange(bool rnw, uint8_t buf[], unsigned int offset, unsigned int bit_cnt)
+static void bitbang_swd_exchange(bool rnw, uint8_t buf[], unsigned int offset, unsigned int bit_cnt)
{
- LOG_DEBUG("bitbang_exchange");
- int tdi;
+ if (bitbang_interface->blink) {
+ /* FIXME: we should manage errors */
+ bitbang_interface->blink(1);
+ }
for (unsigned int i = offset; i < bit_cnt + offset; i++) {
int bytec = i/8;
int bcval = 1 << (i % 8);
- tdi = !rnw && (buf[bytec] & bcval);
+ int swdio = !rnw && (buf[bytec] & bcval);
- bitbang_interface->write(0, 0, tdi);
+ bitbang_interface->swd_write(0, swdio);
if (rnw && buf) {
if (bitbang_interface->swdio_read())
buf[bytec] &= ~bcval;
}
- bitbang_interface->write(1, 0, tdi);
+ bitbang_interface->swd_write(1, swdio);
+ }
+
+ if (bitbang_interface->blink) {
+ /* FIXME: we should manage errors */
+ bitbang_interface->blink(0);
}
}
-int bitbang_swd_switch_seq(enum swd_special_seq seq)
+static int bitbang_swd_switch_seq(enum swd_special_seq seq)
{
- LOG_DEBUG("bitbang_swd_switch_seq");
-
switch (seq) {
case LINE_RESET:
- LOG_DEBUG("SWD line reset");
- bitbang_exchange(false, (uint8_t *)swd_seq_line_reset, 0, swd_seq_line_reset_len);
+ LOG_DEBUG_IO("SWD line reset");
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_line_reset, 0, swd_seq_line_reset_len);
break;
case JTAG_TO_SWD:
LOG_DEBUG("JTAG-to-SWD");
- bitbang_exchange(false, (uint8_t *)swd_seq_jtag_to_swd, 0, swd_seq_jtag_to_swd_len);
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_jtag_to_swd, 0, swd_seq_jtag_to_swd_len);
+ break;
+ case JTAG_TO_DORMANT:
+ LOG_DEBUG("JTAG-to-DORMANT");
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_jtag_to_dormant, 0, swd_seq_jtag_to_dormant_len);
break;
case SWD_TO_JTAG:
LOG_DEBUG("SWD-to-JTAG");
- bitbang_exchange(false, (uint8_t *)swd_seq_swd_to_jtag, 0, swd_seq_swd_to_jtag_len);
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_swd_to_jtag, 0, swd_seq_swd_to_jtag_len);
+ break;
+ case SWD_TO_DORMANT:
+ LOG_DEBUG("SWD-to-DORMANT");
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_swd_to_dormant, 0, swd_seq_swd_to_dormant_len);
+ break;
+ case DORMANT_TO_SWD:
+ LOG_DEBUG("DORMANT-to-SWD");
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_dormant_to_swd, 0, swd_seq_dormant_to_swd_len);
+ break;
+ case DORMANT_TO_JTAG:
+ LOG_DEBUG("DORMANT-to-JTAG");
+ bitbang_swd_exchange(false, (uint8_t *)swd_seq_dormant_to_jtag, 0, swd_seq_dormant_to_jtag_len);
break;
default:
LOG_ERROR("Sequence %d not supported", seq);
return ERROR_OK;
}
-void bitbang_switch_to_swd(void)
-{
- LOG_DEBUG("bitbang_switch_to_swd");
- bitbang_exchange(false, (uint8_t *)swd_seq_jtag_to_swd, 0, swd_seq_jtag_to_swd_len);
-}
-
static void swd_clear_sticky_errors(void)
{
bitbang_swd_write_reg(swd_cmd(false, false, DP_ABORT),
static void bitbang_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay_clk)
{
- LOG_DEBUG("bitbang_swd_read_reg");
- assert(cmd & SWD_CMD_RnW);
+ assert(cmd & SWD_CMD_RNW);
if (queued_retval != ERROR_OK) {
LOG_DEBUG("Skip bitbang_swd_read_reg because queued_retval=%d", queued_retval);
return;
}
- for (;;) {
+ int64_t timeout = timeval_ms() + SWD_WAIT_TIMEOUT;
+ for (unsigned int retry = 0;; retry++) {
uint8_t trn_ack_data_parity_trn[DIV_ROUND_UP(4 + 3 + 32 + 1 + 4, 8)];
- cmd |= SWD_CMD_START | (1 << 7);
- bitbang_exchange(false, &cmd, 0, 8);
+ cmd |= SWD_CMD_START | SWD_CMD_PARK;
+ bitbang_swd_exchange(false, &cmd, 0, 8);
bitbang_interface->swdio_drive(false);
- bitbang_exchange(true, trn_ack_data_parity_trn, 0, 1 + 3 + 32 + 1 + 1);
+ bitbang_swd_exchange(true, trn_ack_data_parity_trn, 0, 1 + 3 + 32 + 1 + 1);
bitbang_interface->swdio_drive(true);
int ack = buf_get_u32(trn_ack_data_parity_trn, 1, 3);
uint32_t data = buf_get_u32(trn_ack_data_parity_trn, 1 + 3, 32);
int parity = buf_get_u32(trn_ack_data_parity_trn, 1 + 3 + 32, 1);
- LOG_DEBUG("%s %s %s reg %X = %08"PRIx32,
- ack == SWD_ACK_OK ? "OK" : ack == SWD_ACK_WAIT ? "WAIT" : ack == SWD_ACK_FAULT ? "FAULT" : "JUNK",
- cmd & SWD_CMD_APnDP ? "AP" : "DP",
- cmd & SWD_CMD_RnW ? "read" : "write",
- (cmd & SWD_CMD_A32) >> 1,
- data);
-
- switch (ack) {
- case SWD_ACK_OK:
- if (parity != parity_u32(data)) {
- LOG_DEBUG("Wrong parity detected");
- queued_retval = ERROR_FAIL;
- return;
- }
- if (value)
- *value = data;
- if (cmd & SWD_CMD_APnDP)
- bitbang_exchange(true, NULL, 0, ap_delay_clk);
- return;
- case SWD_ACK_WAIT:
- LOG_DEBUG("SWD_ACK_WAIT");
+ LOG_CUSTOM_LEVEL((ack != SWD_ACK_OK && (retry == 0 || ack != SWD_ACK_WAIT))
+ ? LOG_LVL_DEBUG : LOG_LVL_DEBUG_IO,
+ "%s %s read reg %X = %08" PRIx32,
+ ack == SWD_ACK_OK ? "OK" : ack == SWD_ACK_WAIT ? "WAIT" : ack == SWD_ACK_FAULT ? "FAULT" : "JUNK",
+ cmd & SWD_CMD_APNDP ? "AP" : "DP",
+ (cmd & SWD_CMD_A32) >> 1,
+ data);
+
+ if (ack == SWD_ACK_WAIT && timeval_ms() <= timeout) {
swd_clear_sticky_errors();
- break;
- case SWD_ACK_FAULT:
- LOG_DEBUG("SWD_ACK_FAULT");
- queued_retval = ack;
+ if (retry > 20)
+ alive_sleep(1);
+
+ continue;
+ }
+ if (retry > 1)
+ LOG_DEBUG("SWD WAIT: retried %u times", retry);
+
+ if (ack != SWD_ACK_OK) {
+ queued_retval = swd_ack_to_error_code(ack);
return;
- default:
- LOG_DEBUG("No valid acknowledge: ack=%d", ack);
- queued_retval = ack;
+ }
+
+ if (parity != parity_u32(data)) {
+ LOG_ERROR("Wrong parity detected");
+ queued_retval = ERROR_FAIL;
return;
}
+ if (value)
+ *value = data;
+ if (cmd & SWD_CMD_APNDP)
+ bitbang_swd_exchange(true, NULL, 0, ap_delay_clk);
+ return;
}
}
static void bitbang_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay_clk)
{
- LOG_DEBUG("bitbang_swd_write_reg");
- assert(!(cmd & SWD_CMD_RnW));
+ assert(!(cmd & SWD_CMD_RNW));
if (queued_retval != ERROR_OK) {
LOG_DEBUG("Skip bitbang_swd_write_reg because queued_retval=%d", queued_retval);
return;
}
- for (;;) {
- uint8_t trn_ack_data_parity_trn[DIV_ROUND_UP(4 + 3 + 32 + 1 + 4, 8)];
+ int64_t timeout = timeval_ms() + SWD_WAIT_TIMEOUT;
+
+ /* Devices do not reply to DP_TARGETSEL write cmd, ignore received ack */
+ bool check_ack = swd_cmd_returns_ack(cmd);
+
+ /* init the array to silence scan-build */
+ uint8_t trn_ack_data_parity_trn[DIV_ROUND_UP(4 + 3 + 32 + 1 + 4, 8)] = {0};
+ for (unsigned int retry = 0;; retry++) {
buf_set_u32(trn_ack_data_parity_trn, 1 + 3 + 1, 32, value);
buf_set_u32(trn_ack_data_parity_trn, 1 + 3 + 1 + 32, 1, parity_u32(value));
- cmd |= SWD_CMD_START | (1 << 7);
- bitbang_exchange(false, &cmd, 0, 8);
+ cmd |= SWD_CMD_START | SWD_CMD_PARK;
+ bitbang_swd_exchange(false, &cmd, 0, 8);
bitbang_interface->swdio_drive(false);
- bitbang_exchange(true, trn_ack_data_parity_trn, 0, 1 + 3 + 1);
+ bitbang_swd_exchange(true, trn_ack_data_parity_trn, 0, 1 + 3);
+
+ /* Avoid a glitch on SWDIO when changing the direction to output.
+ * To keep performance penalty minimal, pre-write the first data
+ * bit to SWDIO GPIO output buffer while clocking the turnaround bit.
+ * Following swdio_drive(true) outputs the pre-written value
+ * and the same value is rewritten by the next swd_write()
+ * instead of glitching SWDIO
+ * HiZ/pull-up --------------> 0 -------------> 1
+ * swdio_drive(true) swd_write(0,1)
+ * in case of data bit 0 = 1
+ */
+ bitbang_swd_exchange(false, trn_ack_data_parity_trn, 1 + 3 + 1, 1);
bitbang_interface->swdio_drive(true);
- bitbang_exchange(false, trn_ack_data_parity_trn, 1 + 3 + 1, 32 + 1);
+ bitbang_swd_exchange(false, trn_ack_data_parity_trn, 1 + 3 + 1, 32 + 1);
int ack = buf_get_u32(trn_ack_data_parity_trn, 1, 3);
- LOG_DEBUG("%s %s %s reg %X = %08"PRIx32,
- ack == SWD_ACK_OK ? "OK" : ack == SWD_ACK_WAIT ? "WAIT" : ack == SWD_ACK_FAULT ? "FAULT" : "JUNK",
- cmd & SWD_CMD_APnDP ? "AP" : "DP",
- cmd & SWD_CMD_RnW ? "read" : "write",
- (cmd & SWD_CMD_A32) >> 1,
- buf_get_u32(trn_ack_data_parity_trn, 1 + 3 + 1, 32));
-
- switch (ack) {
- case SWD_ACK_OK:
- if (cmd & SWD_CMD_APnDP)
- bitbang_exchange(true, NULL, 0, ap_delay_clk);
- return;
- case SWD_ACK_WAIT:
- LOG_DEBUG("SWD_ACK_WAIT");
+ LOG_CUSTOM_LEVEL((check_ack && ack != SWD_ACK_OK && (retry == 0 || ack != SWD_ACK_WAIT))
+ ? LOG_LVL_DEBUG : LOG_LVL_DEBUG_IO,
+ "%s%s %s write reg %X = %08" PRIx32,
+ check_ack ? "" : "ack ignored ",
+ ack == SWD_ACK_OK ? "OK" : ack == SWD_ACK_WAIT ? "WAIT" : ack == SWD_ACK_FAULT ? "FAULT" : "JUNK",
+ cmd & SWD_CMD_APNDP ? "AP" : "DP",
+ (cmd & SWD_CMD_A32) >> 1,
+ buf_get_u32(trn_ack_data_parity_trn, 1 + 3 + 1, 32));
+
+ if (check_ack && ack == SWD_ACK_WAIT && timeval_ms() <= timeout) {
swd_clear_sticky_errors();
- break;
- case SWD_ACK_FAULT:
- LOG_DEBUG("SWD_ACK_FAULT");
- queued_retval = ack;
- return;
- default:
- LOG_DEBUG("No valid acknowledge: ack=%d", ack);
- queued_retval = ack;
+ if (retry > 20)
+ alive_sleep(1);
+
+ continue;
+ }
+
+ if (retry > 1)
+ LOG_DEBUG("SWD WAIT: retried %u times", retry);
+
+ if (check_ack && ack != SWD_ACK_OK) {
+ queued_retval = swd_ack_to_error_code(ack);
return;
}
+
+ if (cmd & SWD_CMD_APNDP)
+ bitbang_swd_exchange(true, NULL, 0, ap_delay_clk);
+ return;
}
}
static int bitbang_swd_run_queue(void)
{
- LOG_DEBUG("bitbang_swd_run_queue");
/* A transaction must be followed by another transaction or at least 8 idle cycles to
* ensure that data is clocked through the AP. */
- bitbang_exchange(true, NULL, 0, 8);
+ bitbang_swd_exchange(true, NULL, 0, 8);
int retval = queued_retval;
queued_retval = ERROR_OK;
- LOG_DEBUG("SWD queue return value: %02x", retval);
+ LOG_DEBUG_IO("SWD queue return value: %02x", retval);
return retval;
}