/************************************************************************************
* drivers/mtd/at25.c
* Driver for SPI-based AT25DF321 (32Mbit) flash.
*
* Copyright (C) 2009-2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
* Petteri Aimonen <jpa@nx.mail.kapsi.fi>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
************************************************************************************/
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/ioctl.h>
#include <nuttx/spi/spi.h>
#include <nuttx/mtd/mtd.h>
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/* Configuration ********************************************************************/
#ifndef CONFIG_AT25_SPIMODE
# define CONFIG_AT25_SPIMODE SPIDEV_MODE0
#endif
#ifndef CONFIG_AT25_SPIFREQUENCY
# define CONFIG_AT25_SPIFREQUENCY 20000000
#endif
/* AT25 Registers *******************************************************************/
/* Indentification register values */
#define AT25_MANUFACTURER 0x1F
#define AT25_AT25DF321_TYPE 0x47 /* 32 M-bit */
/* AT25DF321 capacity is 4,194,304 bytes:
* (64 sectors) * (65,536 bytes per sector)
* (16384 pages) * (256 bytes per page)
*/
#define AT25_AT25DF321_SECTOR_SHIFT 12 /* Sector size 1 << 12 = 4096 */
#define AT25_AT25DF321_NSECTORS 1024
#define AT25_AT25DF321_PAGE_SHIFT 9 /* Page size 1 << 9 = 512 */
#define AT25_AT25DF321_NPAGES 8192
/* Instructions */
/* Command Value N Description Addr Dummy Data */
#define AT25_WREN 0x06 /* 1 Write Enable 0 0 0 */
#define AT25_WRDI 0x04 /* 1 Write Disable 0 0 0 */
#define AT25_RDID 0x9f /* 1 Read Identification 0 0 1-3 */
#define AT25_RDSR 0x05 /* 1 Read Status Register 0 0 >=1 */
#define AT25_WRSR 0x01 /* 1 Write Status Register 0 0 1 */
#define AT25_READ 0x03 /* 1 Read Data Bytes 3 0 >=1 */
#define AT25_FAST_READ 0x0b /* 1 Higher speed read 3 1 >=1 */
#define AT25_PP 0x02 /* 1 Page Program 3 0 1-256 */
#define AT25_SE 0x20 /* 1 Sector Erase 3 0 0 */
#define AT25_BE 0xc7 /* 1 Bulk Erase 0 0 0 */
#define AT25_DP 0xb9 /* 2 Deep power down 0 0 0 */
#define AT25_RES 0xab /* 2 Read Electronic Signature 0 3 >=1 */
/* Status register bit definitions */
#define AT25_SR_BUSY (1 << 0) /* Bit 0: Ready/Busy Status */
#define AT25_SR_WEL (1 << 1) /* Bit 1: Write enable latch bit */
#define AT25_SR_SWP_SHIFT (2) /* Bits 2-3: Software protection */
#define AT25_SR_SWP_MASK (3 << AT25_SR_SWP_SHIFT)
#define AT25_SR_WPP (1 << 4) /* Bit 4: Write Protect (/WP) Pin Status */
#define AT25_SR_EPE (1 << 5) /* Bit 5: Erase/program error */
/* Bit 6: Reserved */
#define AT25_SR_SPRL (1 << 7) /* Bit 7: Sector Protection Registers Locked */
#define AT25_SR_UNPROT 0x00 /* Global unprotect command */
#define AT25_DUMMY 0xa5
/************************************************************************************
* Private Types
************************************************************************************/
/* This type represents the state of the MTD device. The struct mtd_dev_s
* must appear at the beginning of the definition so that you can freely
* cast between pointers to struct mtd_dev_s and struct at25_dev_s.
*/
struct at25_dev_s
{
struct mtd_dev_s mtd; /* MTD interface */
FAR struct spi_dev_s *dev; /* Saved SPI interface instance */
uint8_t sectorshift; /* 16 or 18 */
uint8_t pageshift; /* 8 */
uint16_t nsectors; /* 128 or 64 */
uint32_t npages; /* 32,768 or 65,536 */
};
/************************************************************************************
* Private Function Prototypes
************************************************************************************/
/* Helpers */
static void at25_lock(FAR struct spi_dev_s *dev);
static inline void at25_unlock(FAR struct spi_dev_s *dev);
static inline int at25_readid(struct at25_dev_s *priv);
static void at25_waitwritecomplete(struct at25_dev_s *priv);
static void at25_writeenable(struct at25_dev_s *priv);
static inline void at25_sectorerase(struct at25_dev_s *priv, off_t offset);
static inline int at25_bulkerase(struct at25_dev_s *priv);
static inline void at25_pagewrite(struct at25_dev_s *priv, FAR const uint8_t *buffer,
off_t offset);
/* MTD driver methods */
static int at25_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks);
static ssize_t at25_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buf);
static ssize_t at25_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buf);
static ssize_t at25_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
FAR uint8_t *buffer);
static int at25_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg);
/************************************************************************************
* Private Data
************************************************************************************/
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Name: at25_lock
************************************************************************************/
static void at25_lock(FAR struct spi_dev_s *dev)
{
/* On SPI busses where there are multiple devices, it will be necessary to
* lock SPI to have exclusive access to the busses for a sequence of
* transfers. The bus should be locked before the chip is selected.
*
* This is a blocking call and will not return until we have exclusiv access to
* the SPI buss. We will retain that exclusive access until the bus is unlocked.
*/
(void)SPI_LOCK(dev, true);
/* After locking the SPI bus, the we also need call the setfrequency, setbits, and
* setmode methods to make sure that the SPI is properly configured for the device.
* If the SPI buss is being shared, then it may have been left in an incompatible
* state.
*/
SPI_SETMODE(dev, CONFIG_AT25_SPIMODE);
SPI_SETBITS(dev, 8);
(void)SPI_SETFREQUENCY(dev, CONFIG_AT25_SPIFREQUENCY);
}
/************************************************************************************
* Name: at25_unlock
************************************************************************************/
static inline void at25_unlock(FAR struct spi_dev_s *dev)
{
(void)SPI_LOCK(dev, false);
}
/************************************************************************************
* Name: at25_readid
************************************************************************************/
static inline int at25_readid(struct at25_dev_s *priv)
{
uint16_t manufacturer;
uint16_t memory;
fvdbg("priv: %p\n", priv);
/* Lock the SPI bus, configure the bus, and select this FLASH part. */
at25_lock(priv->dev);
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send the "Read ID (RDID)" command and read the first three ID bytes */
(void)SPI_SEND(priv->dev, AT25_RDID);
manufacturer = SPI_SEND(priv->dev, AT25_DUMMY);
memory = SPI_SEND(priv->dev, AT25_DUMMY);
/* Deselect the FLASH and unlock the bus */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
at25_unlock(priv->dev);
fvdbg("manufacturer: %02x memory: %02x\n",
manufacturer, memory);
/* Check for a valid manufacturer and memory type */
if (manufacturer == AT25_MANUFACTURER && memory == AT25_AT25DF321_TYPE)
{
priv->sectorshift = AT25_AT25DF321_SECTOR_SHIFT;
priv->nsectors = AT25_AT25DF321_NSECTORS;
priv->pageshift = AT25_AT25DF321_PAGE_SHIFT;
priv->npages = AT25_AT25DF321_NPAGES;
return OK;
}
return -ENODEV;
}
/************************************************************************************
* Name: at25_waitwritecomplete
************************************************************************************/
static void at25_waitwritecomplete(struct at25_dev_s *priv)
{
uint8_t status;
/* Are we the only device on the bus? */
#ifdef CONFIG_SPI_OWNBUS
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Read Status Register (RDSR)" command */
(void)SPI_SEND(priv->dev, AT25_RDSR);
/* Loop as long as the memory is busy with a write cycle */
do
{
/* Send a dummy byte to generate the clock needed to shift out the status */
status = SPI_SEND(priv->dev, AT25_DUMMY);
}
while ((status & AT25_SR_BUSY) != 0);
/* Deselect the FLASH */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
#else
/* Loop as long as the memory is busy with a write cycle */
do
{
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Read Status Register (RDSR)" command */
(void)SPI_SEND(priv->dev, AT25_RDSR);
/* Send a dummy byte to generate the clock needed to shift out the status */
status = SPI_SEND(priv->dev, AT25_DUMMY);
/* Deselect the FLASH */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
/* Given that writing could take up to few tens of milliseconds, and erasing
* could take more. The following short delay in the "busy" case will allow
* other peripherals to access the SPI bus.
*/
if ((status & AT25_SR_BUSY) != 0)
{
at25_unlock(priv->dev);
usleep(10000);
at25_lock(priv->dev);
}
}
while ((status & AT25_SR_BUSY) != 0);
#endif
if (status & AT25_SR_EPE)
{
fdbg("ERROR: Write error, status: 0x%02x\n", status);
}
fvdbg("Complete, status: 0x%02x\n", status);
}
/************************************************************************************
* Name: at25_writeenable
************************************************************************************/
static void at25_writeenable(struct at25_dev_s *priv)
{
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
(void)SPI_SEND(priv->dev, AT25_WREN);
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
fvdbg("Enabled\n");
}
/************************************************************************************
* Name: at25_sectorerase
************************************************************************************/
static inline void at25_sectorerase(struct at25_dev_s *priv, off_t sector)
{
off_t offset = sector << priv->sectorshift;
fvdbg("sector: %08lx\n", (long)sector);
/* Wait for any preceding write to complete. We could simplify things by
* perform this wait at the end of each write operation (rather than at
* the beginning of ALL operations), but have the wait first will slightly
* improve performance.
*/
at25_waitwritecomplete(priv);
/* Send write enable instruction */
at25_writeenable(priv);
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send the "Sector Erase (SE)" instruction */
(void)SPI_SEND(priv->dev, AT25_SE);
/* Send the sector offset high byte first. For all of the supported
* parts, the sector number is completely contained in the first byte
* and the values used in the following two bytes don't really matter.
*/
(void)SPI_SEND(priv->dev, (offset >> 16) & 0xff);
(void)SPI_SEND(priv->dev, (offset >> 8) & 0xff);
(void)SPI_SEND(priv->dev, offset & 0xff);
/* Deselect the FLASH */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
fvdbg("Erased\n");
}
/************************************************************************************
* Name: at25_bulkerase
************************************************************************************/
static inline int at25_bulkerase(struct at25_dev_s *priv)
{
fvdbg("priv: %p\n", priv);
/* Wait for any preceding write to complete. We could simplify things by
* perform this wait at the end of each write operation (rather than at
* the beginning of ALL operations), but have the wait first will slightly
* improve performance.
*/
at25_waitwritecomplete(priv);
/* Send write enable instruction */
at25_writeenable(priv);
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send the "Bulk Erase (BE)" instruction */
(void)SPI_SEND(priv->dev, AT25_BE);
/* Deselect the FLASH */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
fvdbg("Return: OK\n");
return OK;
}
/************************************************************************************
* Name: at25_pagewrite
************************************************************************************/
static inline void at25_pagewrite(struct at25_dev_s *priv, FAR const uint8_t *buffer,
off_t page)
{
off_t offset = page << 8;
fvdbg("page: %08lx offset: %08lx\n", (long)page, (long)offset);
/* Wait for any preceding write to complete. We could simplify things by
* perform this wait at the end of each write operation (rather than at
* the beginning of ALL operations), but have the wait first will slightly
* improve performance.
*/
at25_waitwritecomplete(priv);
/* Enable the write access to the FLASH */
at25_writeenable(priv);
/* Select this FLASH part */
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Page Program (PP)" command */
(void)SPI_SEND(priv->dev, AT25_PP);
/* Send the page offset high byte first. */
(void)SPI_SEND(priv->dev, (offset >> 16) & 0xff);
(void)SPI_SEND(priv->dev, (offset >> 8) & 0xff);
(void)SPI_SEND(priv->dev, offset & 0xff);
/* Then write the specified number of bytes */
SPI_SNDBLOCK(priv->dev, buffer, 256);
/* Deselect the FLASH: Chip Select high */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
fvdbg("Written\n");
}
/************************************************************************************
* Name: at25_erase
************************************************************************************/
static int at25_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks)
{
FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev;
size_t blocksleft = nblocks;
fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* Lock access to the SPI bus until we complete the erase */
at25_lock(priv->dev);
while (blocksleft-- > 0)
{
/* Erase each sector */
at25_sectorerase(priv, startblock);
startblock++;
}
at25_unlock(priv->dev);
return (int)nblocks;
}
/************************************************************************************
* Name: at25_bread
************************************************************************************/
static ssize_t at25_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks,
FAR uint8_t *buffer)
{
FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev;
ssize_t nbytes;
fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* On this device, we can handle the block read just like the byte-oriented read */
nbytes = at25_read(dev, startblock << priv->pageshift, nblocks << priv->pageshift, buffer);
if (nbytes > 0)
{
return nbytes >> priv->pageshift;
}
return (int)nbytes;
}
/************************************************************************************
* Name: at25_bwrite
************************************************************************************/
static ssize_t at25_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks,
FAR const uint8_t *buffer)
{
FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev;
size_t blocksleft = nblocks;
fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* Lock the SPI bus and write each page to FLASH */
at25_lock(priv->dev);
while (blocksleft-- > 0)
{
at25_pagewrite(priv, buffer, startblock * 2);
at25_pagewrite(priv, buffer + 256, startblock * 2 + 1);
buffer += 1 << priv->pageshift;
startblock++;
}
at25_unlock(priv->dev);
return nblocks;
}
/************************************************************************************
* Name: at25_read
************************************************************************************/
static ssize_t at25_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
FAR uint8_t *buffer)
{
FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev;
fvdbg("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes);
/* Wait for any preceding write to complete. We could simplify things by
* perform this wait at the end of each write operation (rather than at
* the beginning of ALL operations), but have the wait first will slightly
* improve performance.
*/
at25_waitwritecomplete(priv);
/* Lock the SPI bus and select this FLASH part */
at25_lock(priv->dev);
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
/* Send "Read from Memory " instruction */
(void)SPI_SEND(priv->dev, AT25_READ);
/* Send the page offset high byte first. */
(void)SPI_SEND(priv->dev, (offset >> 16) & 0xff);
(void)SPI_SEND(priv->dev, (offset >> 8) & 0xff);
(void)SPI_SEND(priv->dev, offset & 0xff);
/* Then read all of the requested bytes */
SPI_RECVBLOCK(priv->dev, buffer, nbytes);
/* Deselect the FLASH and unlock the SPI bus */
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
at25_unlock(priv->dev);
fvdbg("return nbytes: %d\n", (int)nbytes);
return nbytes;
}
/************************************************************************************
* Name: at25_ioctl
************************************************************************************/
static int at25_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg)
{
FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev;
int ret = -EINVAL; /* Assume good command with bad parameters */
fvdbg("cmd: %d \n", cmd);
switch (cmd)
{
case MTDIOC_GEOMETRY:
{
FAR struct mtd_geometry_s *geo = (FAR struct mtd_geometry_s *)((uintptr_t)arg);
if (geo)
{
/* Populate the geometry structure with information need to know
* the capacity and how to access the device.
*
* NOTE: that the device is treated as though it where just an array
* of fixed size blocks. That is most likely not true, but the client
* will expect the device logic to do whatever is necessary to make it
* appear so.
*/
geo->blocksize = (1 << priv->pageshift);
geo->erasesize = (1 << priv->sectorshift);
geo->neraseblocks = priv->nsectors;
ret = OK;
fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n",
geo->blocksize, geo->erasesize, geo->neraseblocks);
}
}
break;
case MTDIOC_BULKERASE:
{
/* Erase the entire device */
at25_lock(priv->dev);
ret = at25_bulkerase(priv);
at25_unlock(priv->dev);
}
break;
case MTDIOC_XIPBASE:
default:
ret = -ENOTTY; /* Bad command */
break;
}
fvdbg("return %d\n", ret);
return ret;
}
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: at25_initialize
*
* Description:
* Create an initialize MTD device instance. MTD devices are not registered
* in the file system, but are created as instances that can be bound to
* other functions (such as a block or character driver front end).
*
************************************************************************************/
FAR struct mtd_dev_s *at25_initialize(FAR struct spi_dev_s *dev)
{
FAR struct at25_dev_s *priv;
int ret;
fvdbg("dev: %p\n", dev);
/* Allocate a state structure (we allocate the structure instead of using
* a fixed, static allocation so that we can handle multiple FLASH devices.
* The current implementation would handle only one FLASH part per SPI
* device (only because of the SPIDEV_FLASH definition) and so would have
* to be extended to handle multiple FLASH parts on the same SPI bus.
*/
priv = (FAR struct at25_dev_s *)kzalloc(sizeof(struct at25_dev_s));
if (priv)
{
/* Initialize the allocated structure (unsupported methods were
* nullified by kzalloc).
*/
priv->mtd.erase = at25_erase;
priv->mtd.bread = at25_bread;
priv->mtd.bwrite = at25_bwrite;
priv->mtd.read = at25_read;
priv->mtd.ioctl = at25_ioctl;
priv->dev = dev;
/* Deselect the FLASH */
SPI_SELECT(dev, SPIDEV_FLASH, false);
/* Identify the FLASH chip and get its capacity */
ret = at25_readid(priv);
if (ret != OK)
{
/* Unrecognized! Discard all of that work we just did and return NULL */
fdbg("ERROR: Unrecognized\n");
kfree(priv);
priv = NULL;
}
else
{
/* Unprotect all sectors */
at25_writeenable(priv);
SPI_SELECT(priv->dev, SPIDEV_FLASH, true);
(void)SPI_SEND(priv->dev, AT25_WRSR);
(void)SPI_SEND(priv->dev, AT25_SR_UNPROT);
SPI_SELECT(priv->dev, SPIDEV_FLASH, false);
}
}
/* Register the MTD with the procfs system if enabled */
#ifdef CONFIG_MTD_REGISTRATION
mtd_register(&priv->mtd, "at25");
#endif
/* Return the implementation-specific state structure as the MTD device */
fvdbg("Return %p\n", priv);
return (FAR struct mtd_dev_s *)priv;
}