cortex_m3: report detected error condition in poll

If the CPU crashed at some point, poll will discover this.

Previously the poll fn would clear the error and print a warning,
rather than propagating the error.

The new behavior is to report the error back up, but still
clear the error.

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>

diff --git a/src/target/cortex_m3.c b/src/target/cortex_m3.c
index 3f080f13369ad48284f622cc194aee690b1ea8e6..f2947ad118be189bc68ebb3aea2b14e4da2e29b4 100644 (file)
--- a/src/target/cortex_m3.c
+++ b/src/target/cortex_m3.c
@@ -520,7 +520,8 @@ static int cortex_m3_debug_entry(struct target *target)
 
 static int cortex_m3_poll(struct target *target)
 {
-       int retval;
+       int detected_failure = ERROR_OK;
+       int retval = ERROR_OK;
        enum target_state prev_target_state = target->state;
        struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
        struct adiv5_dap *swjdp = &cortex_m3->armv7m.dap;
@@ -535,15 +536,18 @@ static int cortex_m3_poll(struct target *target)
 
        /* Recover from lockup.  See ARMv7-M architecture spec,
         * section B1.5.15 "Unrecoverable exception cases".
-        *
-        * REVISIT Is there a better way to report and handle this?
         */
        if (cortex_m3->dcb_dhcsr & S_LOCKUP) {
-               LOG_WARNING("%s -- clearing lockup after double fault",
+               LOG_ERROR("%s -- clearing lockup after double fault",
                                target_name(target));
                cortex_m3_write_debug_halt_mask(target, C_HALT, 0);
                target->debug_reason = DBG_REASON_DBGRQ;
 
+               /* We have to execute the rest (the "finally" equivalent, but
+                * still throw this exception again).
+                */
+               detected_failure = ERROR_FAIL;
+
                /* refresh status bits */
                retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
                if (retval != ERROR_OK)
@@ -610,11 +614,14 @@ static int cortex_m3_poll(struct target *target)
                if (cortex_m3->dcb_dhcsr & S_RETIRE_ST)
                {
                        target->state = TARGET_RUNNING;
-                       return ERROR_OK;
+                       retval = ERROR_OK;
                }
        }
 
-       return ERROR_OK;
+       /* Did we detect a failure condition that we cleared? */
+       if (detected_failure != ERROR_OK)
+               retval = detected_failure;
+       return retval;
 }
 
 static int cortex_m3_halt(struct target *target)