+// SPDX-License-Identifier: GPL-2.0-or-later
+
/***************************************************************************
*
* Copyright (C) 2010 by David Brownell
- *
- * 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/>.
***************************************************************************/
/**
* is a transport level interface, with "target/arm_adi_v5.[hc]" code
* understanding operation semantics, shared with the JTAG transport.
*
- * Single-DAP support only.
+ * Single DAP and multidrop-SWD support.
*
* for details, see "ARM IHI 0031A"
* ARM Debug Interface v5 Architecture Specification
static struct adiv5_dap *swd_multidrop_selected_dap;
+static bool swd_multidrop_in_swd_state;
+
static int swd_queue_dp_write_inner(struct adiv5_dap *dap, unsigned int reg,
uint32_t data);
static int swd_run_inner(struct adiv5_dap *dap)
{
const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
- int retval;
-
- retval = swd->run();
-
- if (retval != ERROR_OK) {
- /* fault response */
- dap->do_reconnect = true;
- }
- return retval;
+ return swd->run();
}
static inline int check_sync(struct adiv5_dap *dap)
return do_sync ? swd_run_inner(dap) : ERROR_OK;
}
-/** Select the DP register bank matching bits 7:4 of reg. */
+/** Select the DP register bank */
static int swd_queue_dp_bankselect(struct adiv5_dap *dap, unsigned int reg)
{
- /* Only register address 0 and 4 are banked. */
- if ((reg & 0xf) > 4)
+ /* Only register address 0 (ADIv6 only) and 4 are banked. */
+ if (is_adiv6(dap) ? (reg & 0xf) > 4 : (reg & 0xf) != 4)
return ERROR_OK;
- uint64_t sel = (reg & 0x000000F0) >> 4;
- if (dap->select != DP_SELECT_INVALID)
- sel |= dap->select & ~0xfULL;
+ uint32_t sel = (reg >> 4) & DP_SELECT_DPBANK;
- if (sel == dap->select)
+ /* ADIv6 ensures DPBANKSEL = 0 after line reset */
+ if ((dap->select_valid || (is_adiv6(dap) && dap->select_dpbanksel_valid))
+ && (sel == (dap->select & DP_SELECT_DPBANK)))
return ERROR_OK;
- dap->select = sel;
+ /* Use the AP part of dap->select regardless of dap->select_valid:
+ * if !dap->select_valid
+ * dap->select contains a speculative value likely going to be used
+ * in the following swd_queue_ap_bankselect() */
+ sel |= (uint32_t)(dap->select & SELECT_AP_MASK);
- int retval = swd_queue_dp_write_inner(dap, DP_SELECT, (uint32_t)sel);
- if (retval != ERROR_OK)
- dap->select = DP_SELECT_INVALID;
+ LOG_DEBUG_IO("DP BANK SELECT: %" PRIx32, sel);
- return retval;
+ /* dap->select cache gets updated in the following call */
+ return swd_queue_dp_write_inner(dap, DP_SELECT, sel);
}
static int swd_queue_dp_read_inner(struct adiv5_dap *dap, unsigned int reg,
static int swd_queue_dp_write_inner(struct adiv5_dap *dap, unsigned int reg,
uint32_t data)
{
- int retval;
+ int retval = ERROR_OK;
const struct swd_driver *swd = adiv5_dap_swd_driver(dap);
assert(swd);
swd_finish_read(dap);
if (reg == DP_SELECT) {
- dap->select = data & (DP_SELECT_APSEL | DP_SELECT_APBANK | DP_SELECT_DPBANK);
+ dap->select = data | (dap->select & (0xffffffffull << 32));
swd->write_reg(swd_cmd(false, false, reg), data, 0);
retval = check_sync(dap);
- if (retval != ERROR_OK)
- dap->select = DP_SELECT_INVALID;
+ dap->select_valid = (retval == ERROR_OK);
+ dap->select_dpbanksel_valid = dap->select_valid;
return retval;
}
- retval = swd_queue_dp_bankselect(dap, reg);
- if (retval != ERROR_OK)
- return retval;
+ if (reg == DP_SELECT1)
+ dap->select = ((uint64_t)data << 32) | (dap->select & 0xffffffffull);
- swd->write_reg(swd_cmd(false, false, reg), data, 0);
+ /* DP_ABORT write is not banked.
+ * Prevent writing DP_SELECT before as it would fail on locked up DP */
+ if (reg != DP_ABORT)
+ retval = swd_queue_dp_bankselect(dap, reg);
- return check_sync(dap);
+ if (retval == ERROR_OK) {
+ swd->write_reg(swd_cmd(false, false, reg), data, 0);
+
+ retval = check_sync(dap);
+ }
+
+ if (reg == DP_SELECT1)
+ dap->select1_valid = (retval == ERROR_OK);
+
+ return retval;
}
assert(dap_is_multidrop(dap));
- swd_send_sequence(dap, LINE_RESET);
+ /* Send JTAG_TO_DORMANT and DORMANT_TO_SWD just once
+ * and then use shorter LINE_RESET until communication fails */
+ if (!swd_multidrop_in_swd_state) {
+ swd_send_sequence(dap, JTAG_TO_DORMANT);
+ swd_send_sequence(dap, DORMANT_TO_SWD);
+ } else {
+ swd_send_sequence(dap, LINE_RESET);
+ }
+
+ /*
+ * Zero dap->select and set dap->select_dpbanksel_valid
+ * to skip the write to DP_SELECT before DPIDR read, avoiding
+ * the protocol error.
+ * Clear the other validity flags because the rest of the DP
+ * SELECT and SELECT1 registers is unknown after line reset.
+ */
+ dap->select = 0;
+ dap->select_dpbanksel_valid = true;
+ dap->select_valid = false;
+ dap->select1_valid = false;
retval = swd_queue_dp_write_inner(dap, DP_TARGETSEL, dap->multidrop_targetsel);
if (retval != ERROR_OK)
LOG_DEBUG_IO("Selected DP_TARGETSEL 0x%08" PRIx32, dap->multidrop_targetsel);
swd_multidrop_selected_dap = dap;
+ swd_multidrop_in_swd_state = true;
if (dpidr_ptr)
*dpidr_ptr = dpidr;
swd_multidrop_selected_dap = NULL;
if (retry > 3) {
LOG_ERROR("Failed to select multidrop %s", adiv5_dap_name(dap));
+ dap->do_reconnect = true;
return retval;
}
adiv5_dap_name(dap));
}
+ dap->do_reconnect = false;
return retval;
}
int64_t timeout = timeval_ms() + 500;
do {
- swd_send_sequence(dap, JTAG_TO_DORMANT);
- swd_send_sequence(dap, DORMANT_TO_SWD);
+ /* Do not make any assumptions about SWD state in case of reconnect */
+ if (dap->do_reconnect)
+ swd_multidrop_in_swd_state = false;
/* Clear link state, including the SELECT cache. */
dap->do_reconnect = false;
if (retval == ERROR_OK)
break;
+ swd_multidrop_in_swd_state = false;
alive_sleep(1);
} while (timeval_ms() < timeout);
return retval;
}
+ swd_multidrop_in_swd_state = true;
LOG_INFO("SWD DPIDR 0x%08" PRIx32 ", DLPIDR 0x%08" PRIx32,
dpidr, dlpidr);
/* The sequences to enter in SWD (JTAG_TO_SWD and DORMANT_TO_SWD) end
* with a SWD line reset sequence (50 clk with SWDIO high).
- * From ARM IHI 0074C ADIv6.0, chapter B4.3.3 "Connection and line reset
- * sequence":
- * - line reset sets DP_SELECT_DPBANK to zero;
+ * From ARM IHI 0031F ADIv5.2 and ARM IHI 0074C ADIv6.0,
+ * chapter B4.3.3 "Connection and line reset sequence":
+ * - DPv3 (ADIv6) only: line reset sets DP_SELECT_DPBANK to zero;
* - read of DP_DPIDR takes the connection out of reset;
* - write of DP_TARGETSEL keeps the connection in reset;
* - other accesses return protocol error (SWDIO not driven by target).
*
- * Read DP_DPIDR to get out of reset. Initialize dap->select to zero to
- * skip the write to DP_SELECT, avoiding the protocol error. Set again
- * dap->select to DP_SELECT_INVALID because the rest of the register is
- * unknown after line reset.
+ * dap_invalidate_cache() sets dap->select to zero and all validity
+ * flags to invalid. Set dap->select_dpbanksel_valid only
+ * to skip the write to DP_SELECT, avoiding the protocol error.
+ * Read DP_DPIDR to get out of reset.
*/
- dap->select = 0;
+ dap->select_dpbanksel_valid = true;
+
retval = swd_queue_dp_read_inner(dap, DP_DPIDR, &dpidr);
if (retval == ERROR_OK) {
retval = swd_run_inner(dap);
dap->switch_through_dormant = !dap->switch_through_dormant;
} while (timeval_ms() < timeout);
- dap->select = DP_SELECT_INVALID;
if (retval != ERROR_OK) {
LOG_ERROR("Error connecting DP: cannot read IDR");
return retval;
}
+static int swd_pre_connect(struct adiv5_dap *dap)
+{
+ swd_multidrop_in_swd_state = false;
+
+ return ERROR_OK;
+}
+
static int swd_connect(struct adiv5_dap *dap)
{
int status;
return swd_queue_dp_write_inner(dap, reg, data);
}
-/** Select the AP register bank matching bits 7:4 of reg. */
+/** Select the AP register bank */
static int swd_queue_ap_bankselect(struct adiv5_ap *ap, unsigned reg)
{
int retval;
struct adiv5_dap *dap = ap->dap;
uint64_t sel;
- if (is_adiv6(dap)) {
+ if (is_adiv6(dap))
sel = ap->ap_num | (reg & 0x00000FF0);
- if (sel == (dap->select & ~0xfULL))
- return ERROR_OK;
-
- if (dap->select != DP_SELECT_INVALID)
- sel |= dap->select & 0xf;
- dap->select = sel;
- LOG_DEBUG("AP BANKSEL: %" PRIx64, sel);
-
- retval = swd_queue_dp_write(dap, DP_SELECT, (uint32_t)sel);
+ else
+ sel = (ap->ap_num << 24) | (reg & ADIV5_DP_SELECT_APBANK);
- if (retval == ERROR_OK && dap->asize > 32)
- retval = swd_queue_dp_write(dap, DP_SELECT1, (uint32_t)(sel >> 32));
+ uint64_t sel_diff = (sel ^ dap->select) & SELECT_AP_MASK;
- if (retval != ERROR_OK)
- dap->select = DP_SELECT_INVALID;
+ bool set_select = !dap->select_valid || (sel_diff & 0xffffffffull);
+ bool set_select1 = is_adiv6(dap) && dap->asize > 32
+ && (!dap->select1_valid
+ || sel_diff & (0xffffffffull << 32));
- return retval;
+ if (set_select && set_select1) {
+ /* Prepare DP bank for DP_SELECT1 now to save one write */
+ sel |= (DP_SELECT1 & 0x000000f0) >> 4;
+ } else {
+ /* Use the DP part of dap->select regardless of dap->select_valid:
+ * if !dap->select_valid
+ * dap->select contains a speculative value likely going to be used
+ * in the following swd_queue_dp_bankselect().
+ * Moreover dap->select_valid should never be false here as a DP bank
+ * is always selected before selecting an AP bank */
+ sel |= dap->select & DP_SELECT_DPBANK;
}
- /* ADIv5 */
- sel = (ap->ap_num << 24) | (reg & 0x000000F0);
- if (dap->select != DP_SELECT_INVALID)
- sel |= dap->select & DP_SELECT_DPBANK;
+ if (set_select) {
+ LOG_DEBUG_IO("AP BANK SELECT: %" PRIx32, (uint32_t)sel);
- if (sel == dap->select)
- return ERROR_OK;
+ retval = swd_queue_dp_write(dap, DP_SELECT, (uint32_t)sel);
+ if (retval != ERROR_OK)
+ return retval;
+ }
- dap->select = sel;
+ if (set_select1) {
+ LOG_DEBUG_IO("AP BANK SELECT1: %" PRIx32, (uint32_t)(sel >> 32));
- retval = swd_queue_dp_write_inner(dap, DP_SELECT, sel);
- if (retval != ERROR_OK)
- dap->select = DP_SELECT_INVALID;
+ retval = swd_queue_dp_write(dap, DP_SELECT1, (uint32_t)(sel >> 32));
+ if (retval != ERROR_OK)
+ return retval;
+ }
- return retval;
+ return ERROR_OK;
}
static int swd_queue_ap_read(struct adiv5_ap *ap, unsigned reg,
swd_finish_read(dap);
- return swd_run_inner(dap);
+ retval = swd_run_inner(dap);
+ if (retval != ERROR_OK) {
+ /* fault response */
+ dap->do_reconnect = true;
+ }
+
+ return retval;
}
/** Put the SWJ-DP back to JTAG mode */
done = true;
if (dap_is_multidrop(dap)) {
+ /* Emit the switch seq to dormant state regardless the state mirrored
+ * in swd_multidrop_in_swd_state. Doing so ensures robust operation
+ * in the case the variable is out of sync.
+ * Sending SWD_TO_DORMANT makes no change if the DP is already dormant. */
swd->switch_seq(SWD_TO_DORMANT);
+ swd_multidrop_in_swd_state = false;
/* Revisit!
* Leaving DPs in dormant state was tested and offers some safety
* against DPs mismatch in case of unintentional use of non-multidrop SWD.
}
const struct dap_ops swd_dap_ops = {
+ .pre_connect_init = swd_pre_connect,
.connect = swd_connect,
.send_sequence = swd_send_sequence,
.queue_dp_read = swd_queue_dp_read,
* REVISIT can we verify "just one SWD DAP" here/early?
*/
.name = "newdap",
- .jim_handler = jim_jtag_newtap,
+ .handler = handle_jtag_newtap,
.mode = COMMAND_CONFIG,
- .help = "declare a new SWD DAP"
+ .help = "declare a new SWD DAP",
+ .usage = "basename dap_type ['-irlen' count] "
+ "['-enable'|'-disable'] "
+ "['-expected_id' number] "
+ "['-ignore-version'] "
+ "['-ignore-bypass'] "
+ "['-ircapture' number] "
+ "['-ir-bypass' number] "
+ "['-mask' number]",
},
COMMAND_REGISTRATION_DONE
};