norflash: Wait for WSM bit in lock/unlock

lock/unlock operation must wait until WSM bit
is set. Since we do not allow to loop forever then these functions
must return an error if WSM bit isn't enabled after a number of tries.

Change-Id: I21c9e292b514b28786ff4a225128bcd8c1bfa999
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

include/plat/arm/board/common/drivers/norflash.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -37,8 +37,8 @@
 /* Public API */
 void nor_send_cmd(uintptr_t base_addr, unsigned long cmd);
 int nor_word_program(uintptr_t base_addr, unsigned long data);
-void nor_lock(uintptr_t base_addr);
-void nor_unlock(uintptr_t base_addr);
+int nor_lock(uintptr_t base_addr);
+int nor_unlock(uintptr_t base_addr);
 
 #endif /* __NORFLASH_H_ */
 

plat/arm/board/common/drivers/norflash/norflash.c

@@ -25,6 +25,7 @@
  * model
  */
 #define DWS_WORD_PROGRAM_RETRIES	1000
+#define DWS_WORD_LOCK_RETRIES		1000
 
 /* Helper macro to detect end of command */
 #define NOR_CMD_END (NOR_DWS | NOR_DWS << 16l)
@@ -89,20 +90,38 @@ int nor_word_program(uintptr_t base_addr, unsigned long data)
 
 /*
  * Lock a full 256 block
+ * Return values:
+ *  0 = success
+ *  otherwise it returns a negative value
  */
-void nor_lock(uintptr_t base_addr)
+int nor_lock(uintptr_t base_addr)
 {
+	int ret;
+
 	nor_send_cmd(base_addr, NOR_CMD_LOCK_UNLOCK);
 	mmio_write_32(base_addr, NOR_2X16(NOR_LOCK_BLOCK));
+
+	ret = nor_poll_dws(base_addr, DWS_WORD_LOCK_RETRIES);
 	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
+
+	return ret;
 }
 
 /*
  * unlock a full 256 block
+ * Return values:
+ *  0 = success
+ *  otherwise it returns a negative value
  */
-void nor_unlock(uintptr_t base_addr)
+int nor_unlock(uintptr_t base_addr)
 {
+	int ret;
+
 	nor_send_cmd(base_addr, NOR_CMD_LOCK_UNLOCK);
 	mmio_write_32(base_addr, NOR_2X16(NOR_UNLOCK_BLOCK));
+
+	ret = nor_poll_dws(base_addr, DWS_WORD_LOCK_RETRIES);
 	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
+
+	return ret;
 }