norflash: Add full status check

The nor_XXXXX functions may fail due to different reasons, and it
is convenient to do a full check to detect any failure. It is also
a good idea to have a specific function to do a full status check,
because new checks can be added to this function and they will be
incorporated automatically to any function calling it.

Change-Id: I54fed913e37ef574c1608e94139a519426348d12
Signed-off-by: Roberto Vargas <roberto.vargas@arm.com>

1 files changed, 56 insertions, 15 deletions

diff --git a/plat/arm/board/common/drivers/norflash/norflash.c b/plat/arm/board/common/drivers/norflash/norflash.c
index e0047c006..722cf33ee 100644
--- a/plat/arm/board/common/drivers/norflash/norflash.c
+++ b/plat/arm/board/common/drivers/norflash/norflash.c
@@ -8,16 +8,6 @@
 #include <mmio.h>
 #include <norflash.h>
 
-/*
- * This file supplies a low level interface to the vexpress NOR flash
- * memory of juno and fvp. This memory is organized as an interleaved
- * memory of two chips with a 16 bit word. It means that every 32 bit
- * access is going to access to two different chips. This is very
- * important when we send commands or read status of the chips
- */
-
-/* Helper macros to access two flash banks in parallel */
-#define NOR_2X16(d)			((d << 16) | (d & 0xffff))
 
 /*
  * DWS ready poll retries. The number of retries in this driver have been
@@ -32,7 +22,30 @@
 #define NOR_CMD_END (NOR_DWS | NOR_DWS << 16l)
 
 /*
- * Poll Write State Machine. Return values:
+ * This file supplies a low level interface to the vexpress NOR flash
+ * memory of juno and fvp. This memory is organized as an interleaved
+ * memory of two chips with a 16 bit word. It means that every 32 bit
+ * access is going to access to two different chips. This is very
+ * important when we send commands or read status of the chips
+ */
+
+/* Helper macros to access two flash banks in parallel */
+#define NOR_2X16(d)			((d << 16) | (d & 0xffff))
+
+static unsigned int nor_status(uintptr_t base_addr)
+{
+	unsigned long status;
+
+	nor_send_cmd(base_addr, NOR_CMD_READ_STATUS_REG);
+	status = mmio_read_32(base_addr);
+	status |= status >> 16; /* merge status from both flash banks */
+
+	return status & 0xFFFF;
+}
+
+/*
+ * Poll Write State Machine.
+ * Return values:
  *    0      = WSM ready
  *    -EBUSY = WSM busy after the number of retries
  */
@@ -50,6 +63,26 @@ static int nor_poll_dws(uintptr_t base_addr, unsigned long int retries)
 	return -EBUSY;
 }
 
+/*
+ * Return values:
+ *    0      = success
+ *    -EPERM = Device protected or Block locked
+ *    -EIO   = General I/O error
+ */
+static int nor_full_status_check(uintptr_t base_addr)
+{
+	unsigned long status;
+
+	/* Full status check */
+	status = nor_status(base_addr);
+
+	if (status & (NOR_PS | NOR_BLS | NOR_ESS | NOR_PSS))
+		return -EPERM;
+	if (status & (NOR_VPPS | NOR_ES))
+		return -EIO;
+	return 0;
+}
+
 void nor_send_cmd(uintptr_t base_addr, unsigned long cmd)
 {
 	mmio_write_32(base_addr, NOR_2X16(cmd));
@@ -60,9 +93,8 @@ void nor_send_cmd(uintptr_t base_addr, unsigned long cmd)
  * can reset bits that were previously set. It cannot set bits that
  * were previously reset. The resulting bits = old_bits & new bits.
  * Return values:
- *    0      = success
- *    -EBUSY = WSM not ready
- *    -EPERM = Device protected or Block locked
+ *  0 = success
+ *  otherwise it returns a negative value
  */
 int nor_word_program(uintptr_t base_addr, unsigned long data)
 {
@@ -87,7 +119,10 @@ int nor_word_program(uintptr_t base_addr, unsigned long data)
 		}
 	}
 
+	if (ret == 0)
+		ret = nor_full_status_check(base_addr);
 	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
+
 	return ret;
 }
 
@@ -95,7 +130,7 @@ int nor_word_program(uintptr_t base_addr, unsigned long data)
  * Erase a full 256K block
  * Return values:
  *  0 = success
- * -EBUSY = WSM not ready
+ *  otherwise it returns a negative value
  */
 int nor_erase(uintptr_t base_addr)
 {
@@ -107,6 +142,8 @@ int nor_erase(uintptr_t base_addr)
 	nor_send_cmd(base_addr, NOR_CMD_BLOCK_ERASE_ACK);
 
 	ret = nor_poll_dws(base_addr, DWS_WORD_ERASE_RETRIES);
+	if (ret == 0)
+		ret = nor_full_status_check(base_addr);
 	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
 
 	return ret;
@@ -128,6 +165,8 @@ int nor_lock(uintptr_t base_addr)
 	nor_send_cmd(base_addr, NOR_LOCK_BLOCK);
 
 	ret = nor_poll_dws(base_addr, DWS_WORD_LOCK_RETRIES);
+	if (ret == 0)
+		ret = nor_full_status_check(base_addr);
 	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
 
 	return ret;
@@ -149,6 +188,8 @@ int nor_unlock(uintptr_t base_addr)
 	nor_send_cmd(base_addr, NOR_UNLOCK_BLOCK);
 
 	ret = nor_poll_dws(base_addr, DWS_WORD_LOCK_RETRIES);
+	if (ret == 0)
+		ret = nor_full_status_check(base_addr);
 	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
 
 	return ret;