Fix for BMIPS

BMIPS always needs 2 additional instructions to reach the core.
Seems there is a 2 instructions fifo between the tap and the core, or it behaves in this way.
No idea of the purpose of this fifo, I can only guess.
Of course function mips32_pracc_clean_text_jump() must add this additional instructions (NOPs).
Only tested on bcm3348..

Change-Id: I3183d3ce865d469d7262ba4b15446e5743a5f1df
Signed-off-by: Salvador Arroyo <salvador@telecable.es>
Reviewed-on: http://openocd.zylin.com/2270
Tested-by: jenkins
Reviewed-by: Kent Brinkley <jkbrinkley.imgtec@gmail.com>
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

diff --git a/src/target/mips32_pracc.c b/src/target/mips32_pracc.c
index e97626cb2eb702700935c32ba4740a8beacf33c4..c08e3249aa1f42e0d7ee4d4c9230e7b5cf9cf212 100644 (file)
--- a/src/target/mips32_pracc.c
+++ b/src/target/mips32_pracc.c
@@ -160,19 +160,22 @@ int mips32_pracc_clean_text_jump(struct mips_ejtag *ejtag_info)
                        return retval;
        }
 
-       if (ejtag_info->mode != 0)      /* done, queued mode won't work with lexra cores */
+       if (ejtag_info->mode != 0)      /* async mode support only for MIPS ... */
                return ERROR_OK;
 
-       retval = mips32_pracc_read_ctrl_addr(ejtag_info);
-       if (retval != ERROR_OK)
-               return retval;
-
-       if (ejtag_info->pa_addr != MIPS32_PRACC_TEXT) {                 /* LEXRA/BMIPS ?, shift out another NOP */
-               mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
-               mips_ejtag_drscan_32_out(ejtag_info, MIPS32_NOP);
-               retval = mips32_pracc_finish(ejtag_info);
+       for (int i = 0; i != 2; i++) {
+               retval = mips32_pracc_read_ctrl_addr(ejtag_info);
                if (retval != ERROR_OK)
                        return retval;
+
+               if (ejtag_info->pa_addr != MIPS32_PRACC_TEXT) {         /* LEXRA/BMIPS ?, shift out another NOP, max 2 */
+                       mips_ejtag_set_instr(ejtag_info, EJTAG_INST_DATA);
+                       mips_ejtag_drscan_32_out(ejtag_info, MIPS32_NOP);
+                       retval = mips32_pracc_finish(ejtag_info);
+                       if (retval != ERROR_OK)
+                               return retval;
+               } else
+                       break;
        }
 
        return ERROR_OK;