David Brownell <david-b@pacbell.net>

[fw/openocd] / src / target / armv4_5.c

diff --git a/src/target/armv4_5.c b/src/target/armv4_5.c
index 9f9aa2f5f037111893763cb29f47f6d8c48f0367..eedbc702d6750792f7cb252e900252ee1524238a 100644 (file)
--- a/src/target/armv4_5.c
+++ b/src/target/armv4_5.c
@@ -532,7 +532,10 @@ static int armv4_5_run_algorithm_completion(struct target_s *target, uint32_t ex
                }
                return ERROR_TARGET_TIMEOUT;
        }
-       if (buf_get_u32(armv4_5->core_cache->reg_list[15].value, 0, 32) != exit_point)
+
+       /* fast exit: ARMv5+ code can use BKPT */
+       if (exit_point && buf_get_u32(armv4_5->core_cache->reg_list[15].value,
+                               0, 32) != exit_point)
        {
                LOG_WARNING("target reentered debug state, but not at the desired exit point: 0x%4.4" PRIx32 "",
                        buf_get_u32(armv4_5->core_cache->reg_list[15].value, 0, 32));
@@ -570,6 +573,13 @@ int armv4_5_run_algorithm_inner(struct target_s *target, int num_mem_params, mem
        if (armv4_5_mode_to_number(armv4_5->core_mode)==-1)
                return ERROR_FAIL;
 
+       /* armv5 and later can terminate with BKPT instruction; less overhead */
+       if (!exit_point && armv4_5->is_armv4)
+       {
+               LOG_ERROR("ARMv4 target needs HW breakpoint location");
+               return ERROR_FAIL;
+       }
+
        for (i = 0; i <= 16; i++)
        {
                if (!ARMV4_5_CORE_REG_MODE(armv4_5->core_cache, armv4_5_algorithm_info->core_mode, i).valid)
@@ -626,9 +636,11 @@ int armv4_5_run_algorithm_inner(struct target_s *target, int num_mem_params, mem
                armv4_5->core_cache->reg_list[ARMV4_5_CPSR].valid = 1;
        }
 
-       if ((retval = breakpoint_add(target, exit_point, exit_breakpoint_size, BKPT_HARD)) != ERROR_OK)
+       /* terminate using a hardware or (ARMv5+) software breakpoint */
+       if (exit_point && (retval = breakpoint_add(target, exit_point,
+                               exit_breakpoint_size, BKPT_HARD)) != ERROR_OK)
        {
-               LOG_ERROR("can't add breakpoint to finish algorithm execution");
+               LOG_ERROR("can't add HW breakpoint to terminate algorithm");
                return ERROR_TARGET_FAILURE;
        }
 
@@ -639,7 +651,8 @@ int armv4_5_run_algorithm_inner(struct target_s *target, int num_mem_params, mem
        int retvaltemp;
        retval = run_it(target, exit_point, timeout_ms, arch_info);
 
-       breakpoint_remove(target, exit_point);
+       if (exit_point)
+               breakpoint_remove(target, exit_point);
 
        if (retval != ERROR_OK)
                return retval;