cortex-a: use -dbgbase option

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

src/target/cortex_a.c

@@ -1861,7 +1861,7 @@ static int cortex_a8_examine_first(struct target *target)
 	int i;
 	int retval = ERROR_OK;
 	uint32_t didr, ctypr, ttypr, cpuid;
-	uint32_t dbgbase, apid;
+	uint32_t dbgbase;
 
 	/* We do one extra read to ensure DAP is configured,
 	 * we call ahbap_debugport_init(swjdp) instead
@@ -1870,10 +1870,17 @@ static int cortex_a8_examine_first(struct target *target)
 	if (retval != ERROR_OK)
 		return retval;
 
-	/* Get ROM Table base */
-	retval = dap_get_debugbase(swjdp, 1, &dbgbase, &apid);
-	if (retval != ERROR_OK)
-		return retval;
+	if (!target->dbgbase_set)
+	{
+		/* Get ROM Table base */
+		uint32_t apid;
+		retval = dap_get_debugbase(swjdp, 1, &dbgbase, &apid);
+		if (retval != ERROR_OK)
+			return retval;
+	} else
+	{
+		dbgbase = target->dbgbase;
+	}
 
 	/* Lookup 0x15 -- Processor DAP */
 	retval = dap_lookup_cs_component(swjdp, 1, dbgbase, 0x15,