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

diff --git a/src/jtag/core.c b/src/jtag/core.c
index 0b752ea426037c58a8317a66b0e6fda210bf4b0a..e6bde518f61659cb9e8aef3f99174433b54ba9a2 100644 (file)
--- a/src/jtag/core.c
+++ b/src/jtag/core.c
@@ -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);
-
-                               retval = ERROR_JTAG_INIT_FAILED;
-                               goto done;
-                       }
+               /* 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;
                }
                LOG_DEBUG("%s: IR capture 0x%0*x", jtag_tap_name(tap),
                                (tap->ir_length + 7) / tap->ir_length, val);