plat: marvell: armada: a8k: check CCU window state before loading MSS BL2

Make sure the current CCU window is not in use before adding
a new address map during MSS BL2 image load preparations.
At BL2 stage the CCU Win-2 points to DRAM. If additional mapping is
added to MSS BL2 stage initialization, the DDR entry will be destroyed
and lead to the system hang.

Change-Id: I215e83508acc37d54dab6954d791b9a74cc883ca
Signed-off-by: Konstantin Porotchkin <kostap@marvell.com>

plat/marvell/armada/a8k/common/mss/mss_bl2_setup.c

@@ -63,10 +63,15 @@ static int bl2_plat_mmap_init(void)
 	 * Do not touch CCU window 0,
 	 * it's used for the internal registers access
 	 */
-	for (cfg_idx = 0, win_id = 1; cfg_idx < cfg_num; cfg_idx++, win_id++) {
+	for (cfg_idx = 0, win_id = 1;
+	     (win_id < MVEBU_CCU_MAX_WINS) && (cfg_idx < cfg_num); win_id++) {
+		/* Skip already enabled CCU windows */
+		if (ccu_is_win_enabled(MVEBU_AP0, win_id))
+			continue;
 		/* Enable required CCU windows */
 		ccu_win_check(&ccu_mem_map[cfg_idx]);
 		ccu_enable_win(MVEBU_AP0, &ccu_mem_map[cfg_idx], win_id);
+		cfg_idx++;
 	}
 
 	/* Config address for each cp other than cp0 */