openocd newtap -defer-examine option

commit 57176f5a5e08f10bfadcb7a027661cea304c5547
Author: Esben Haabendal <esben@haabendal.dk>
Date:   Tue Oct 27 21:42:14 2015 +0100

    Add -defer-examine option to jtag newtap command
    
    Change-Id: I41dcf927c7e0137f45c30fce7c8f8c38c877519e
    Signed-off-by: Esben Haabendal <esben@haabendal.dk>

diff --git a/src/jtag/jtag.h b/src/jtag/jtag.h
index eda4ccd..b1f003e 100644
--- a/src/jtag/jtag.h
+++ b/src/jtag/jtag.h
@@ -127,6 +127,8 @@ struct jtag_tap {
        int abs_chain_position;
        /** Is this TAP disabled after JTAG reset? */
        bool disabled_after_reset;
+       /** Should we defer examine to later */
+       bool defer_examine;
        /** Is this TAP currently enabled? */
        bool enabled;
        int ir_length; /**< size of instruction register */
diff --git a/src/jtag/tcl.c b/src/jtag/tcl.c
index c916fb1..b461147 100644
--- a/src/jtag/tcl.c
+++ b/src/jtag/tcl.c
@@ -454,6 +454,7 @@ static int jim_newtap_expected_id(Jim_Nvp *n, Jim_GetOptInfo *goi,
 #define NTAP_OPT_DISABLED  4
 #define NTAP_OPT_EXPECTED_ID 5
 #define NTAP_OPT_VERSION   6
+#define NTAP_OPT_DEFER_EXAMINE 7
 
 static int jim_newtap_ir_param(Jim_Nvp *n, Jim_GetOptInfo *goi,
        struct jtag_tap *pTap)
@@ -516,6 +517,7 @@ static int jim_newtap_cmd(Jim_GetOptInfo *goi)
                { .name = "-disable",       .value = NTAP_OPT_DISABLED },
                { .name = "-expected-id",       .value = NTAP_OPT_EXPECTED_ID },
                { .name = "-ignore-version",       .value = NTAP_OPT_VERSION },
+               { .name = "-defer-examine", .value = NTAP_OPT_DEFER_EXAMINE },
                { .name = NULL,       .value = -1 },
        };
 
@@ -599,6 +601,9 @@ static int jim_newtap_cmd(Jim_GetOptInfo *goi)
                    case NTAP_OPT_VERSION:
                            pTap->ignore_version = true;
                            break;
+                   case NTAP_OPT_DEFER_EXAMINE:
+                           pTap->defer_examine = true;
+                           break;
                }       /* switch (n->value) */
        }       /* while (goi->argc) */
 
diff --git a/src/target/target.c b/src/target/target.c
index 19e5d65..df82e4c 100644
--- a/src/target/target.c
+++ b/src/target/target.c
@@ -729,6 +729,9 @@ int target_examine(void)
                        continue;
                }
 
+               if (target->tap->defer_examine)
+                       continue;
+
                retval = target_examine_one(target);
                if (retval != ERROR_OK)
                        return retval;