drivers/bitbang: add support for SWD multidrop

Ignore ack received after DP_TARGETSEL write to prevent false error.

This change also fixes a bug:
Received ACK FAULT or JUNK value were incorrectly stored to queued_retval
and later used as bitbang_swd_run_queue() error return.

Use LOG_ERROR for parity mismatch.

Change-Id: I5ff1f658f221af78d8bbec8416a7a0fc64ba2550
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: https://review.openocd.org/c/openocd/+/6700
Tested-by: jenkins
Reviewed-by: Antonio Borneo <borneo.antonio@gmail.com>
This commit is contained in:
Tomas Vanek 2021-11-12 15:28:30 +01:00 committed by Antonio Borneo
parent d569b9bd68
commit 9dd39a33e6
1 changed files with 34 additions and 43 deletions

View File

@ -492,17 +492,22 @@ static void bitbang_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay
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,
LOG_DEBUG("%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_RNW ? "read" : "write",
(cmd & SWD_CMD_A32) >> 1,
data);
switch (ack) {
case SWD_ACK_OK:
if (ack == SWD_ACK_WAIT) {
swd_clear_sticky_errors();
continue;
} else if (ack != SWD_ACK_OK) {
queued_retval = swd_ack_to_error_code(ack);
return;
}
if (parity != parity_u32(data)) {
LOG_DEBUG("Wrong parity detected");
LOG_ERROR("Wrong parity detected");
queued_retval = ERROR_FAIL;
return;
}
@ -511,19 +516,6 @@ static void bitbang_swd_read_reg(uint8_t cmd, uint32_t *value, uint32_t ap_delay
if (cmd & SWD_CMD_APNDP)
bitbang_swd_exchange(true, NULL, 0, ap_delay_clk);
return;
case SWD_ACK_WAIT:
LOG_DEBUG("SWD_ACK_WAIT");
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;
return;
}
}
}
@ -537,6 +529,9 @@ static void bitbang_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay
return;
}
/* Devices do not reply to DP_TARGETSEL write cmd, ignore received ack */
bool check_ack = swd_cmd_returns_ack(cmd);
for (;;) {
uint8_t trn_ack_data_parity_trn[DIV_ROUND_UP(4 + 3 + 32 + 1 + 4, 8)];
buf_set_u32(trn_ack_data_parity_trn, 1 + 3 + 1, 32, value);
@ -551,31 +546,27 @@ static void bitbang_swd_write_reg(uint8_t cmd, uint32_t value, uint32_t ap_delay
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,
LOG_DEBUG("%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_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 (check_ack) {
if (ack == SWD_ACK_WAIT) {
swd_clear_sticky_errors();
continue;
} else if (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;
case SWD_ACK_WAIT:
LOG_DEBUG("SWD_ACK_WAIT");
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;
return;
}
}
}