Merge pull request #1061 from robertovargas-arm/norflash

nor-flash

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

 /*
- * 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
  */
@@ -19,6 +19,7 @@
 #define NOR_CMD_WORD_PROGRAM		0x40
 #define NOR_CMD_BLOCK_ERASE		0x20
 #define NOR_CMD_LOCK_UNLOCK		0x60
+#define NOR_CMD_BLOCK_ERASE_ACK		0xD0
 
 /* Second bus cycle */
 #define NOR_LOCK_BLOCK			0x01
@@ -37,8 +38,9 @@
 /* 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);
+int nor_erase(uintptr_t base_addr);
 
 #endif /* __NORFLASH_H_ */
 

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

 /*
- * 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
  */
@@ -8,8 +8,6 @@
 #include <mmio.h>
 #include <norflash.h>
 
-/* 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
@@ -17,32 +15,72 @@
  * model
  */
 #define DWS_WORD_PROGRAM_RETRIES	1000
+#define DWS_WORD_ERASE_RETRIES		3000000
+#define DWS_WORD_LOCK_RETRIES		1000
+
+/* Helper macro to detect end of command */
+#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
  */
-static int nor_poll_dws(uintptr_t base_addr, unsigned int retries)
+static int nor_poll_dws(uintptr_t base_addr, unsigned long int retries)
 {
-	uint32_t status;
-	int ret;
+	unsigned long status;
 
-	for (;;) {
+	do {
 		nor_send_cmd(base_addr, NOR_CMD_READ_STATUS_REG);
 		status = mmio_read_32(base_addr);
-		if ((status & NOR_DWS) &&
-		    (status & (NOR_DWS << 16))) {
-			ret = 0;
-			break;
-		}
-		if (retries-- == 0) {
-			ret = -EBUSY;
-			break;
-		}
-	}
+		if ((status & NOR_CMD_END) == NOR_CMD_END)
+			return 0;
+	} while (retries-- > 0);
 
-	return ret;
+	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)
@@ -51,50 +89,108 @@ void nor_send_cmd(uintptr_t base_addr, unsigned long cmd)
 }
 
 /*
+ * This function programs a word in the flash. Be aware that it only
+ * 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)
 {
 	uint32_t status;
 	int ret;
 
+	nor_send_cmd(base_addr, NOR_CMD_CLEAR_STATUS_REG);
+
 	/* Set the device in write word mode */
 	nor_send_cmd(base_addr, NOR_CMD_WORD_PROGRAM);
 	mmio_write_32(base_addr, data);
 
 	ret = nor_poll_dws(base_addr, DWS_WORD_PROGRAM_RETRIES);
-	if (ret != 0) {
-		goto word_program_end;
+	if (ret == 0) {
+		/* Full status check */
+		nor_send_cmd(base_addr, NOR_CMD_READ_STATUS_REG);
+		status = mmio_read_32(base_addr);
+
+		if (status & (NOR_PS | NOR_BLS)) {
+			nor_send_cmd(base_addr, NOR_CMD_CLEAR_STATUS_REG);
+			ret = -EPERM;
+		}
 	}
 
-	/* Full status check */
-	nor_send_cmd(base_addr, NOR_CMD_READ_STATUS_REG);
-	status = mmio_read_32(base_addr);
+	if (ret == 0)
+		ret = nor_full_status_check(base_addr);
+	nor_send_cmd(base_addr, NOR_CMD_READ_ARRAY);
 
-	if (status & (NOR_PS | NOR_BLS)) {
-		nor_send_cmd(base_addr, NOR_CMD_CLEAR_STATUS_REG);
-		ret = -EPERM;
-	}
+	return ret;
+}
 
-word_program_end:
+/*
+ * Erase a full 256K block
+ * Return values:
+ *  0 = success
+ *  otherwise it returns a negative value
+ */
+int nor_erase(uintptr_t base_addr)
+{
+	int ret;
+
+	nor_send_cmd(base_addr, NOR_CMD_CLEAR_STATUS_REG);
+
+	nor_send_cmd(base_addr, NOR_CMD_BLOCK_ERASE);
+	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;
 }
 
-void nor_lock(uintptr_t base_addr)
+/*
+ * Lock a full 256 block
+ * Return values:
+ *  0 = success
+ *  otherwise it returns a negative value
+ */
+int nor_lock(uintptr_t base_addr)
 {
+	int ret;
+
+	nor_send_cmd(base_addr, NOR_CMD_CLEAR_STATUS_REG);
+
 	nor_send_cmd(base_addr, NOR_CMD_LOCK_UNLOCK);
-	mmio_write_32(base_addr, NOR_2X16(NOR_LOCK_BLOCK));
+	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;
 }
 
-void nor_unlock(uintptr_t base_addr)
+/*
+ * unlock a full 256 block
+ * Return values:
+ *  0 = success
+ *  otherwise it returns a negative value
+ */
+int nor_unlock(uintptr_t base_addr)
 {
+	int ret;
+
+	nor_send_cmd(base_addr, NOR_CMD_CLEAR_STATUS_REG);
+
 	nor_send_cmd(base_addr, NOR_CMD_LOCK_UNLOCK);
-	mmio_write_32(base_addr, NOR_2X16(NOR_UNLOCK_BLOCK));
+	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;
+}