interesting
/
riscv-openocd
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Simplified BSCAN related scanning fields.

This commit is contained in:
Greg Savin 2019-04-08 12:01:02 -07:00
parent a740a06bbc
commit 7f18c48b83
2 changed files with 20 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

21
src/target/riscv/riscv-013.c
View File

@ -508,12 +508,8 @@ static dmi_status_t dmi_scan(struct target *target, uint32_t *address_in,
if (target->bscan_tunnel_ir_width != 0) {
jtag_add_ir_scan(target->tap, &select_user4, TAP_IDLE);
uint8_t out_right_shifted_by_one[num_bytes];
uint8_t tunneled_dr_width[4] = {num_bits};
memcpy(out_right_shifted_by_one, out, num_bytes);
buffer_shr(out_right_shifted_by_one, num_bytes, 1);
struct scan_field tunneled_dr[] = {
{
.num_bits = 1,
@ -525,15 +521,11 @@ static dmi_status_t dmi_scan(struct target *target, uint32_t *address_in,
.out_value = tunneled_dr_width,
.in_value = NULL,
},
/* for BSCAN tunnel, there is a one-TCK skew between shift in and shift out, so splitting the DR payload into 2 fields */
/* for BSCAN tunnel, there is a one-TCK skew between shift in and shift out, so
scanning num_bits + 1, and then will right shift the input field after executing the queues */
{
.num_bits = 1,
.num_bits = num_bits+1,
.out_value = out,
.in_value = NULL,
},
{
.num_bits = num_bits,
.out_value = out_right_shifted_by_one,
.in_value = in,
},
{
@ -562,6 +554,13 @@ static dmi_status_t dmi_scan(struct target *target, uint32_t *address_in,
return DMI_STATUS_FAILED;
}
#if BUILD_RISCV_ARTY_BSCAN == 1
if (target->bscan_tunnel_ir_width != 0) {
/* need to right-shift "in" by one bit, because of clock skew between BSCAN TAP and DM TAP */
buffer_shr(in, num_bytes, 1);
}
#endif
if (data_in)
*data_in = buf_get_u32(in, DTM_DMI_DATA_OFFSET, DTM_DMI_DATA_LENGTH);

23
src/target/riscv/riscv.c
View File

@ -255,11 +255,10 @@ uint32_t dtmcontrol_scan_via_bscan(struct target *target, uint32_t out)
/* On BSCAN TAP: Select IR=USER4, issue tunneled IR scan via BSCAN TAP's DR */
uint8_t tunneled_ir_width[4] = {target->bscan_tunnel_ir_width};
uint8_t tunneled_dr_width[4] = {32};
uint8_t out_0[4] = {out & 0x1};
uint8_t out_31_1[4];
uint8_t in_value[4];
uint8_t out_value[5];
uint8_t in_value[5];
buf_set_u32(out_31_1, 0, 32, (out >> 1));
buf_set_u32(out_value, 0, 32, out);
struct scan_field tunneled_ir[] = {
{
@ -295,15 +294,11 @@ uint32_t dtmcontrol_scan_via_bscan(struct target *target, uint32_t out)
.out_value = tunneled_dr_width,
.in_value = NULL,
},
/* for BSCAN tunnel, there is a one-TCK skew between shift in and shift out, so splitting the DR payload into 2 fields */
/* for BSCAN tunnel, there is a one-TCK skew between shift in and shift out,
so scanning 33 bits and then right shifting the in_value after the scan is completed */
{
.num_bits = 1,
.out_value = out_0,
.in_value = NULL,
},
{
.num_bits = 32,
.out_value = out_31_1,
.num_bits = 32+1,
.out_value = out_value,
.in_value = in_value,
},
{
@ -324,7 +319,9 @@ uint32_t dtmcontrol_scan_via_bscan(struct target *target, uint32_t out)
return retval;
}
uint32_t in = buf_get_u32(in_value, 0, 32);
/* Note the starting offset is bit 1, not bit 0. In BSCAN tunnel, there is a one-bit TCK skew between
output and input */
uint32_t in = buf_get_u32(in_value, 1, 32);
LOG_DEBUG("DTMCS: 0x%x -> 0x%x", out, in);
return in;