ARM semihosting: use breakpoint on ARM7

Fall back to software breakpoint when vector catch isn't available.

Possible enhancements:

 - add extra optional command parameter to select high vectors
 - add extra optional command parameter to select hardware breakpoint

Signed-off-by: Nicolas Pitre <nico@marvell.com>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

diff --git a/src/target/arm7_9_common.c b/src/target/arm7_9_common.c
index 25f8cb3206e8616c76f539bfffb6ba86026aa789..905e1082c2b88d1b2a802500fc97ab5726ef488f 100644 (file)
--- a/src/target/arm7_9_common.c
+++ b/src/target/arm7_9_common.c
@@ -2835,7 +2835,6 @@ COMMAND_HANDLER(handle_arm7_9_semihosting_command)
 
                COMMAND_PARSE_ENABLE(CMD_ARGV[0], semihosting);
 
-               /* TODO: support other methods if vector catch is unavailable */
                if (arm7_9->has_vector_catch) {
                        struct reg *vector_catch = &arm7_9->eice_cache
                                        ->reg_list[EICE_VEC_CATCH];
@@ -2844,14 +2843,17 @@ COMMAND_HANDLER(handle_arm7_9_semihosting_command)
                                embeddedice_read_reg(vector_catch);
                        buf_set_u32(vector_catch->value, 2, 1, semihosting);
                        embeddedice_store_reg(vector_catch);
+               } else {
+                       /* TODO: allow optional high vectors and/or BKPT_HARD */
+                       if (semihosting)
+                               breakpoint_add(target, 8, 4, BKPT_SOFT);
+                       else
+                               breakpoint_remove(target, 8); 
+               }
 
-                       /* FIXME never let that "catch" be dropped! */
-
-                       arm7_9->armv4_5_common.is_semihosting = semihosting;
+               /* FIXME never let that "catch" be dropped! */
+               arm7_9->armv4_5_common.is_semihosting = semihosting;
 
-               } else if (semihosting) {
-                       command_print(CMD_CTX, "vector catch unavailable");
-               }
        }
 
        command_print(CMD_CTX, "semihosting is %s",