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Adjustments.

This commit is contained in:
Greg Savin 2019-01-15 17:32:55 -08:00
parent 069a04bcec
commit 2c83052b73
1 changed files with 28 additions and 26 deletions
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54
src/jtag/drivers/ftdi.c
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@ -504,7 +504,7 @@ static void ftdi_execute_pathmove(struct jtag_command *cmd)
}
#if BUILD_FTDI_BSCAN == 1
static void bscan_single_field_data_scan(struct mpsse_ctx *ctx, const uint8_t *out, unsigned out_offset, uint8_t *in,
static void bscan_single_field_data_scan(const uint8_t *out, unsigned out_offset, uint8_t *in,
unsigned in_offset, unsigned length)
{
DO_CLOCK_DATA(mpsse_ctx,
@ -542,6 +542,8 @@ static void bscan_single_field_data_scan(struct mpsse_ctx *ctx, const uint8_t *o
static void ftdi_execute_scan_via_bscan(struct jtag_command *cmd)
{
static const uint8_t zero;
DEBUG_JTAG_IO("%s type:%d", cmd->cmd.scan->ir_scan ? "IRSCAN" : "DRSCAN",
jtag_scan_type(cmd->cmd.scan));
@ -564,7 +566,7 @@ static void ftdi_execute_scan_via_bscan(struct jtag_command *cmd)
// Do the 6-bit IR scan of 0x23 (USER4)
bscan_single_field_data_scan(mpsse_ctx, &bscan_ir_user, 0, NULL, 0, bscan_ir_user_width);
bscan_single_field_data_scan(&bscan_ir_user, 0, NULL, 0, bscan_ir_user_width);
if (tap_get_state() != tap_get_end_state())
move_to_state(tap_get_end_state());
@ -593,7 +595,6 @@ static void ftdi_execute_scan_via_bscan(struct jtag_command *cmd)
ftdi_jtag_mode);
struct scan_field *prevfield = NULL;
uint8_t bitbucket;
for (i = 0, field = cmd->cmd.scan->fields; i < cmd->cmd.scan->num_fields; i++, field++) {
DEBUG_JTAG_IO("%s%s field %d/%d %d bits",
@ -603,42 +604,43 @@ static void ftdi_execute_scan_via_bscan(struct jtag_command *cmd)
cmd->cmd.scan->num_fields,
field->num_bits);
// TDO output is off by one clock from TDI, so can't do an in/out MPSSE call,
// have to:
// Clock field data out
// Clock one bit in, prev_field->in_value at offset prev_field->num_bits-1 or discard if no prev field
// Clock width-1 bits in, assign to field->in_value at offset 0
// TDO output is off by one clock from TDI, so the sequence is slightly more
// involved than a single aligned OUT/IN
// Clock first bit out, place IN bit in highest bit of prev field if there is a prev field
// Clock rest of bits out, place IN bits in bit zero of in
DO_CLOCK_DATA(mpsse_ctx,
field->out_value,
0,
NULL,
0,
field->num_bits,
prevfield ? prevfield->in_value : NULL,
prevfield ? prevfield->num_bits-1 : 0,
1,
ftdi_jtag_mode);
if (prevfield)
DO_CLOCK_DATA(mpsse_ctx,
NULL,
DO_CLOCK_DATA(mpsse_ctx,
field->out_value,
1,
field->in_value,
0,
field->num_bits-1,
ftdi_jtag_mode);
prevfield = field;
}
// There is still one bit left to retrieve in TDO, because of the one clock delay
DO_CLOCK_DATA(mpsse_ctx,
&zero,
0,
prevfield->in_value,
prevfield->num_bits-1,
1,
ftdi_jtag_mode);
else
DO_CLOCK_DATA(mpsse_ctx,
NULL,
0,
&bitbucket,
0,
1,
ftdi_jtag_mode);
prevfield = field;
}
// shift in epilogue and exit shift state
bscan_single_field_data_scan(mpsse_ctx, &epilogue, 0, NULL, 0, 2);
bscan_single_field_data_scan(&epilogue, 0, NULL, 0, 2);
if (tap_get_state() != tap_get_end_state())
move_to_state(tap_get_end_state());