Better fix for TAPs violating the JTAG spec for IR-Capture.

Instead of just assuming all IDCODE-deprived TAPs violate the
JTAG spec (they don't!), just require TAPs with such problems
to be declared with proper ircapture/irmask values.  Example,
with mask and value of zero.


git-svn-id: svn://svn.berlios.de/openocd/trunk@2823 b42882b7-edfa-0310-969c-e2dbd0fdcd60
This commit is contained in:
dbrownell 2009-10-07 18:51:11 +00:00
parent 7035b37e71
commit 246ff4f601
1 changed files with 17 additions and 15 deletions

View File

@ -1108,22 +1108,24 @@ static int jtag_validate_ircapture(void)
break;
}
if (tap->hasidcode)
{
/* Validate the two LSBs, which must be 01 per JTAG spec.
* REVISIT we might be able to verify some MSBs too, using
* ircapture/irmask attributes.
*/
val = buf_get_u32(ir_test, chain_pos, tap->ir_length);
if ((val & 0x3) != 1) {
LOG_ERROR("%s: IR capture error; saw 0x%0*x not 0x..1",
jtag_tap_name(tap),
(tap->ir_length + 7) / tap->ir_length,
val);
/* Validate the two LSBs, which must be 01 per JTAG spec.
*
* Or ... more bits could be provided by TAP declaration.
* Plus, some taps (notably in i.MX series chips) violate
* this part of the JTAG spec, so their capture mask/value
* attributes might disable this test.
*/
val = buf_get_u32(ir_test, chain_pos, tap->ir_length);
if ((val & tap->ir_capture_mask) != tap->ir_capture_value) {
LOG_ERROR("%s: IR capture error; saw 0x%0*x not 0x%0*x",
jtag_tap_name(tap),
(tap->ir_length + 7) / tap->ir_length,
val,
(tap->ir_length + 7) / tap->ir_length,
tap->ir_capture_value);
retval = ERROR_JTAG_INIT_FAILED;
goto done;
}
retval = ERROR_JTAG_INIT_FAILED;
goto done;
}
LOG_DEBUG("%s: IR capture 0x%0*x", jtag_tap_name(tap),
(tap->ir_length + 7) / tap->ir_length, val);