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apache / nuttx / 350fa87fea6df20a7c470330d88222cee8cd6df0 / . / drivers / mtd / w25.c
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/************************************************************************************
* drivers/mtd/w25.c
* Driver for SPI-based W25x16, x32, and x64 and W25q16, q32, q64, and q128 FLASH
*
* Copyright (C) 2012-2013 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <string.h>
#include <assert.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 ********************************************************************/
/* Per the data sheet, the W25 parts can be driven with either SPI mode 0 (CPOL=0
* and CPHA=0) or mode 3 (CPOL=1 and CPHA=1). But I have heard that other devices
* can operate in mode 0 or 1. So you may need to specify CONFIG_W25_SPIMODE to
* select the best mode for your device. If CONFIG_W25_SPIMODE is not defined,
* mode 0 will be used.
*/
#ifndef CONFIG_W25_SPIMODE
# define CONFIG_W25_SPIMODE SPIDEV_MODE0
#endif
/* SPI Frequency. May be up to 25MHz. */
#ifndef CONFIG_W25_SPIFREQUENCY
# define CONFIG_W25_SPIFREQUENCY 20000000
#endif
/* W25 Instructions *****************************************************************/
/* Command Value Description */
/* */
#define W25_WREN 0x06 /* Write enable */
#define W25_WRDI 0x04 /* Write Disable */
#define W25_RDSR 0x05 /* Read status register */
#define W25_WRSR 0x01 /* Write Status Register */
#define W25_RDDATA 0x03 /* Read data bytes */
#define W25_FRD 0x0b /* Higher speed read */
#define W25_FRDD 0x3b /* Fast read, dual output */
#define W25_PP 0x02 /* Program page */
#define W25_BE 0xd8 /* Block Erase (64KB) */
#define W25_SE 0x20 /* Sector erase (4KB) */
#define W25_CE 0xc7 /* Chip erase */
#define W25_PD 0xb9 /* Power down */
#define W25_PURDID 0xab /* Release PD, Device ID */
#define W25_RDMFID 0x90 /* Read Manufacturer / Device */
#define W25_JEDEC_ID 0x9f /* JEDEC ID read */
/* W25 Registers ********************************************************************/
/* Read ID (RDID) register values */
#define W25_MANUFACTURER 0xef /* Winbond Serial Flash */
#define W25X16_DEVID 0x14 /* W25X16 device ID (0xab, 0x90) */
#define W25X32_DEVID 0x15 /* W25X16 device ID (0xab, 0x90) */
#define W25X64_DEVID 0x16 /* W25X16 device ID (0xab, 0x90) */
/* JEDEC Read ID register values */
#define W25_JEDEC_MANUFACTURER 0xef /* SST manufacturer ID */
#define W25X_JEDEC_MEMORY_TYPE 0x30 /* W25X memory type */
#define W25Q_JEDEC_MEMORY_TYPE_A 0x40 /* W25Q memory type */
#define W25Q_JEDEC_MEMORY_TYPE_B 0x60 /* W25Q memory type */
#define W25Q_JEDEC_MEMORY_TYPE_C 0x50 /* W25Q memory type */
#define W25_JEDEC_CAPACITY_8MBIT 0x14 /* 256x4096 = 8Mbit memory capacity */
#define W25_JEDEC_CAPACITY_16MBIT 0x15 /* 512x4096 = 16Mbit memory capacity */
#define W25_JEDEC_CAPACITY_32MBIT 0x16 /* 1024x4096 = 32Mbit memory capacity */
#define W25_JEDEC_CAPACITY_64MBIT 0x17 /* 2048x4096 = 64Mbit memory capacity */
#define W25_JEDEC_CAPACITY_128MBIT 0x18 /* 4096x4096 = 128Mbit memory capacity */
#define NSECTORS_8MBIT 256 /* 256 sectors x 4096 bytes/sector = 1Mb */
#define NSECTORS_16MBIT 512 /* 512 sectors x 4096 bytes/sector = 2Mb */
#define NSECTORS_32MBIT 1024 /* 1024 sectors x 4096 bytes/sector = 4Mb */
#define NSECTORS_64MBIT 2048 /* 2048 sectors x 4096 bytes/sector = 8Mb */
#define NSECTORS_128MBIT 4096 /* 4096 sectors x 4096 bytes/sector = 16Mb */
/* Status register bit definitions */
#define W25_SR_BUSY (1 << 0) /* Bit 0: Write in progress */
#define W25_SR_WEL (1 << 1) /* Bit 1: Write enable latch bit */
#define W25_SR_BP_SHIFT (2) /* Bits 2-5: Block protect bits */
#define W25_SR_BP_MASK (15 << W25_SR_BP_SHIFT)
# define W25X16_SR_BP_NONE (0 << W25_SR_BP_SHIFT) /* Unprotected */
# define W25X16_SR_BP_UPPER32nd (1 << W25_SR_BP_SHIFT) /* Upper 32nd */
# define W25X16_SR_BP_UPPER16th (2 << W25_SR_BP_SHIFT) /* Upper 16th */
# define W25X16_SR_BP_UPPER8th (3 << W25_SR_BP_SHIFT) /* Upper 8th */
# define W25X16_SR_BP_UPPERQTR (4 << W25_SR_BP_SHIFT) /* Upper quarter */
# define W25X16_SR_BP_UPPERHALF (5 << W25_SR_BP_SHIFT) /* Upper half */
# define W25X16_SR_BP_ALL (6 << W25_SR_BP_SHIFT) /* All sectors */
# define W25X16_SR_BP_LOWER32nd (9 << W25_SR_BP_SHIFT) /* Lower 32nd */
# define W25X16_SR_BP_LOWER16th (10 << W25_SR_BP_SHIFT) /* Lower 16th */
# define W25X16_SR_BP_LOWER8th (11 << W25_SR_BP_SHIFT) /* Lower 8th */
# define W25X16_SR_BP_LOWERQTR (12 << W25_SR_BP_SHIFT) /* Lower quarter */
# define W25X16_SR_BP_LOWERHALF (13 << W25_SR_BP_SHIFT) /* Lower half */
# define W25X32_SR_BP_NONE (0 << W25_SR_BP_SHIFT) /* Unprotected */
# define W25X32_SR_BP_UPPER64th (1 << W25_SR_BP_SHIFT) /* Upper 64th */
# define W25X32_SR_BP_UPPER32nd (2 << W25_SR_BP_SHIFT) /* Upper 32nd */
# define W25X32_SR_BP_UPPER16th (3 << W25_SR_BP_SHIFT) /* Upper 16th */
# define W25X32_SR_BP_UPPER8th (4 << W25_SR_BP_SHIFT) /* Upper 8th */
# define W25X32_SR_BP_UPPERQTR (5 << W25_SR_BP_SHIFT) /* Upper quarter */
# define W25X32_SR_BP_UPPERHALF (6 << W25_SR_BP_SHIFT) /* Upper half */
# define W25X32_SR_BP_ALL (7 << W25_SR_BP_SHIFT) /* All sectors */
# define W25X32_SR_BP_LOWER64th (9 << W25_SR_BP_SHIFT) /* Lower 64th */
# define W25X32_SR_BP_LOWER32nd (10 << W25_SR_BP_SHIFT) /* Lower 32nd */
# define W25X32_SR_BP_LOWER16th (11 << W25_SR_BP_SHIFT) /* Lower 16th */
# define W25X32_SR_BP_LOWER8th (12 << W25_SR_BP_SHIFT) /* Lower 8th */
# define W25X32_SR_BP_LOWERQTR (13 << W25_SR_BP_SHIFT) /* Lower quarter */
# define W25X32_SR_BP_LOWERHALF (14 << W25_SR_BP_SHIFT) /* Lower half */
# define W25X64_SR_BP_NONE (0 << W25_SR_BP_SHIFT) /* Unprotected */
# define W25X64_SR_BP_UPPER64th (1 << W25_SR_BP_SHIFT) /* Upper 64th */
# define W25X64_SR_BP_UPPER32nd (2 << W25_SR_BP_SHIFT) /* Upper 32nd */
# define W25X64_SR_BP_UPPER16th (3 << W25_SR_BP_SHIFT) /* Upper 16th */
# define W25X64_SR_BP_UPPER8th (4 << W25_SR_BP_SHIFT) /* Upper 8th */
# define W25X64_SR_BP_UPPERQTR (5 << W25_SR_BP_SHIFT) /* Upper quarter */
# define W25X64_SR_BP_UPPERHALF (6 << W25_SR_BP_SHIFT) /* Upper half */
# define W25X46_SR_BP_ALL (7 << W25_SR_BP_SHIFT) /* All sectors */
# define W25X64_SR_BP_LOWER64th (9 << W25_SR_BP_SHIFT) /* Lower 64th */
# define W25X64_SR_BP_LOWER32nd (10 << W25_SR_BP_SHIFT) /* Lower 32nd */
# define W25X64_SR_BP_LOWER16th (11 << W25_SR_BP_SHIFT) /* Lower 16th */
# define W25X64_SR_BP_LOWER8th (12 << W25_SR_BP_SHIFT) /* Lower 8th */
# define W25X64_SR_BP_LOWERQTR (13 << W25_SR_BP_SHIFT) /* Lower quarter */
# define W25X64_SR_BP_LOWERHALF (14 << W25_SR_BP_SHIFT) /* Lower half */
/* Bit 6: Reserved */
#define W25_SR_SRP (1 << 7) /* Bit 7: Status register write protect */
#define W25_DUMMY 0xa5
/* Chip Geometries ******************************************************************/
/* All members of the family support uniform 4K-byte sectors and 256 byte pages */
#define W25_SECTOR_SHIFT 12 /* Sector size 1 << 12 = 4Kb */
#define W25_SECTOR_SIZE (1 << 12) /* Sector size 1 << 12 = 4Kb */
#define W25_PAGE_SHIFT 8 /* Sector size 1 << 8 = 256b */
#define W25_PAGE_SIZE (1 << 8) /* Sector size 1 << 8 = 256b */
#ifdef CONFIG_W25_SECTOR512 /* Simulate a 512 byte sector */
# define W25_SECTOR512_SHIFT 9 /* Sector size 1 << 9 = 512 bytes */
# define W25_SECTOR512_SIZE (1 << 9) /* Sector size 1 << 9 = 512 bytes */
#endif
#define W25_ERASED_STATE 0xff /* State of FLASH when erased */
/* Cache flags */
#define W25_CACHE_VALID (1 << 0) /* 1=Cache has valid data */
#define W25_CACHE_DIRTY (1 << 1) /* 1=Cache is dirty */
#define W25_CACHE_ERASED (1 << 2) /* 1=Backing FLASH is erased */
#define IS_VALID(p) ((((p)->flags) & W25_CACHE_VALID) != 0)
#define IS_DIRTY(p) ((((p)->flags) & W25_CACHE_DIRTY) != 0)
#define IS_ERASED(p) ((((p)->flags) & W25_CACHE_DIRTY) != 0)
#define SET_VALID(p) do { (p)->flags |= W25_CACHE_VALID; } while (0)
#define SET_DIRTY(p) do { (p)->flags |= W25_CACHE_DIRTY; } while (0)
#define SET_ERASED(p) do { (p)->flags |= W25_CACHE_DIRTY; } while (0)
#define CLR_VALID(p) do { (p)->flags &= ~W25_CACHE_VALID; } while (0)
#define CLR_DIRTY(p) do { (p)->flags &= ~W25_CACHE_DIRTY; } while (0)
#define CLR_ERASED(p) do { (p)->flags &= ~W25_CACHE_DIRTY; } while (0)
/************************************************************************************
* 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 w25_dev_s.
*/
struct w25_dev_s
{
struct mtd_dev_s mtd; /* MTD interface */
FAR struct spi_dev_s *spi; /* Saved SPI interface instance */
uint16_t nsectors; /* Number of erase sectors */
#if defined(CONFIG_W25_SECTOR512) && !defined(CONFIG_W25_READONLY)
uint8_t flags; /* Buffered sector flags */
uint16_t esectno; /* Erase sector number in the cache*/
FAR uint8_t *sector; /* Allocated sector data */
#endif
};
/************************************************************************************
* Private Function Prototypes
************************************************************************************/
/* Helpers */
static void w25_lock(FAR struct spi_dev_s *spi);
static inline void w25_unlock(FAR struct spi_dev_s *spi);
static inline int w25_readid(FAR struct w25_dev_s *priv);
#ifndef CONFIG_W25_READONLY
static void w25_unprotect(FAR struct w25_dev_s *priv);
#endif
static uint8_t w25_waitwritecomplete(FAR struct w25_dev_s *priv);
static inline void w25_wren(FAR struct w25_dev_s *priv);
static inline void w25_wrdi(FAR struct w25_dev_s *priv);
static void w25_sectorerase(FAR struct w25_dev_s *priv, off_t offset);
static inline int w25_chiperase(FAR struct w25_dev_s *priv);
static void w25_byteread(FAR struct w25_dev_s *priv, FAR uint8_t *buffer,
off_t address, size_t nbytes);
#ifndef CONFIG_W25_READONLY
static void w25_pagewrite(FAR struct w25_dev_s *priv, FAR const uint8_t *buffer,
off_t address, size_t nbytes);
#endif
#ifdef CONFIG_W25_SECTOR512
static void w25_cacheflush(struct w25_dev_s *priv);
static FAR uint8_t *w25_cacheread(struct w25_dev_s *priv, off_t sector);
static void w25_cacheerase(struct w25_dev_s *priv, off_t sector);
static void w25_cachewrite(FAR struct w25_dev_s *priv, FAR const uint8_t *buffer,
off_t sector, size_t nsectors);
#endif
/* MTD driver methods */
static int w25_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks);
static ssize_t w25_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buf);
static ssize_t w25_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buf);
static ssize_t w25_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
FAR uint8_t *buffer);
static int w25_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg);
/************************************************************************************
* Private Data
************************************************************************************/
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Name: w25_lock
************************************************************************************/
static void w25_lock(FAR struct spi_dev_s *spi)
{
/* 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(spi, 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(spi, CONFIG_W25_SPIMODE);
SPI_SETBITS(spi, 8);
(void)SPI_SETFREQUENCY(spi, CONFIG_W25_SPIFREQUENCY);
}
/************************************************************************************
* Name: w25_unlock
************************************************************************************/
static inline void w25_unlock(FAR struct spi_dev_s *spi)
{
(void)SPI_LOCK(spi, false);
}
/************************************************************************************
* Name: w25_readid
************************************************************************************/
static inline int w25_readid(struct w25_dev_s *priv)
{
uint16_t manufacturer;
uint16_t memory;
uint16_t capacity;
fvdbg("priv: %p\n", priv);
/* Lock the SPI bus, configure the bus, and select this FLASH part. */
w25_lock(priv->spi);
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send the "Read ID (RDID)" command and read the first three ID bytes */
(void)SPI_SEND(priv->spi, W25_JEDEC_ID);
manufacturer = SPI_SEND(priv->spi, W25_DUMMY);
memory = SPI_SEND(priv->spi, W25_DUMMY);
capacity = SPI_SEND(priv->spi, W25_DUMMY);
/* Deselect the FLASH and unlock the bus */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
w25_unlock(priv->spi);
fvdbg("manufacturer: %02x memory: %02x capacity: %02x\n",
manufacturer, memory, capacity);
/* Check for a valid manufacturer and memory type */
if (manufacturer == W25_JEDEC_MANUFACTURER &&
(memory == W25X_JEDEC_MEMORY_TYPE ||
memory == W25Q_JEDEC_MEMORY_TYPE_A ||
memory == W25Q_JEDEC_MEMORY_TYPE_B ||
memory == W25Q_JEDEC_MEMORY_TYPE_C))
{
/* Okay.. is it a FLASH capacity that we understand? If so, save
* the FLASH capacity.
*/
/* 8M-bit / 1M-byte
*
* W25Q80BV
*/
if (capacity == W25_JEDEC_CAPACITY_8MBIT)
{
priv->nsectors = NSECTORS_8MBIT;
}
/* 16M-bit / 2M-byte (2,097,152)
*
* W24X16, W25Q16BV, W25Q16CL, W25Q16CV, W25Q16DW
*/
else if (capacity == W25_JEDEC_CAPACITY_16MBIT)
{
priv->nsectors = NSECTORS_16MBIT;
}
/* 32M-bit / M-byte (4,194,304)
*
* W25X32, W25Q32BV, W25Q32DW
*/
else if (capacity == W25_JEDEC_CAPACITY_32MBIT)
{
priv->nsectors = NSECTORS_32MBIT;
}
/* 64M-bit / 8M-byte (8,388,608)
*
* W25X64, W25Q64BV, W25Q64CV, W25Q64DW
*/
else if (capacity == W25_JEDEC_CAPACITY_64MBIT)
{
priv->nsectors = NSECTORS_64MBIT;
}
/* 128M-bit / 16M-byte (16,777,216)
*
* W25Q128BV
*/
else if (capacity == W25_JEDEC_CAPACITY_128MBIT)
{
priv->nsectors = NSECTORS_128MBIT;
}
else
{
/* Nope.. we don't understand this capacity. */
return -ENODEV;
}
return OK;
}
/* We don't understand the manufacturer or the memory type */
return -ENODEV;
}
/************************************************************************************
* Name: w25_unprotect
************************************************************************************/
#ifndef CONFIG_W25_READONLY
static void w25_unprotect(FAR struct w25_dev_s *priv)
{
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send "Write enable (WREN)" */
w25_wren(priv);
/* Re-select this FLASH part (This might not be necessary... but is it shown in
* the SST25 timing diagrams from which this code was leveraged.)
*/
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send "Write enable status (EWSR)" */
SPI_SEND(priv->spi, W25_WRSR);
/* Following by the new status value */
SPI_SEND(priv->spi, 0);
SPI_SEND(priv->spi, 0);
}
#endif
/************************************************************************************
* Name: w25_waitwritecomplete
************************************************************************************/
static uint8_t w25_waitwritecomplete(struct w25_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->spi, SPIDEV_FLASH, true);
/* Send "Read Status Register (RDSR)" command */
(void)SPI_SEND(priv->spi, W25_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->spi, W25_DUMMY);
}
while ((status & W25_SR_BUSY) != 0);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
#else
/* Loop as long as the memory is busy with a write cycle */
do
{
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send "Read Status Register (RDSR)" command */
(void)SPI_SEND(priv->spi, W25_RDSR);
/* Send a dummy byte to generate the clock needed to shift out the status */
status = SPI_SEND(priv->spi, W25_DUMMY);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, 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 0 /* Makes writes too slow */
if ((status & W25_SR_BUSY) != 0)
{
w25_unlock(priv->spi);
usleep(1000);
w25_lock(priv->spi);
}
#endif
}
while ((status & W25_SR_BUSY) != 0);
#endif
return status;
}
/************************************************************************************
* Name: w25_wren
************************************************************************************/
static inline void w25_wren(struct w25_dev_s *priv)
{
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send "Write Enable (WREN)" command */
(void)SPI_SEND(priv->spi, W25_WREN);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
}
/************************************************************************************
* Name: w25_wrdi
************************************************************************************/
static inline void w25_wrdi(struct w25_dev_s *priv)
{
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send "Write Disable (WRDI)" command */
(void)SPI_SEND(priv->spi, W25_WRDI);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
}
/************************************************************************************
* Name: w25_sectorerase
************************************************************************************/
static void w25_sectorerase(struct w25_dev_s *priv, off_t sector)
{
off_t address = sector << W25_SECTOR_SHIFT;
fvdbg("sector: %08lx\n", (long)sector);
/* Wait for any preceding write or erase operation to complete. */
(void)w25_waitwritecomplete(priv);
/* Send write enable instruction */
w25_wren(priv);
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send the "Sector Erase (SE)" instruction */
(void)SPI_SEND(priv->spi, W25_SE);
/* Send the sector address high byte first. Only the most significant bits (those
* corresponding to the sector) have any meaning.
*/
(void)SPI_SEND(priv->spi, (address >> 16) & 0xff);
(void)SPI_SEND(priv->spi, (address >> 8) & 0xff);
(void)SPI_SEND(priv->spi, address & 0xff);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
}
/************************************************************************************
* Name: w25_chiperase
************************************************************************************/
static inline int w25_chiperase(struct w25_dev_s *priv)
{
fvdbg("priv: %p\n", priv);
/* Wait for any preceding write or erase operation to complete. */
(void)w25_waitwritecomplete(priv);
/* Send write enable instruction */
w25_wren(priv);
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send the "Chip Erase (CE)" instruction */
(void)SPI_SEND(priv->spi, W25_CE);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
fvdbg("Return: OK\n");
return OK;
}
/************************************************************************************
* Name: w25_byteread
************************************************************************************/
static void w25_byteread(FAR struct w25_dev_s *priv, FAR uint8_t *buffer,
off_t address, size_t nbytes)
{
uint8_t status;
fvdbg("address: %08lx nbytes: %d\n", (long)address, (int)nbytes);
/* Wait for any preceding write or erase operation to complete. */
status = w25_waitwritecomplete(priv);
DEBUGASSERT((status & (W25_SR_WEL|W25_SR_BP_MASK)) == 0);
/* Make sure that writing is disabled */
w25_wrdi(priv);
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send "Read from Memory " instruction */
#ifdef CONFIG_W25_SLOWREAD
(void)SPI_SEND(priv->spi, W25_RDDATA);
#else
(void)SPI_SEND(priv->spi, W25_FRD);
#endif
/* Send the address high byte first. */
(void)SPI_SEND(priv->spi, (address >> 16) & 0xff);
(void)SPI_SEND(priv->spi, (address >> 8) & 0xff);
(void)SPI_SEND(priv->spi, address & 0xff);
/* Send a dummy byte */
#ifndef CONFIG_W25_SLOWREAD
(void)SPI_SEND(priv->spi, W25_DUMMY);
#endif
/* Then read all of the requested bytes */
SPI_RECVBLOCK(priv->spi, buffer, nbytes);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
}
/************************************************************************************
* Name: w25_pagewrite
************************************************************************************/
#ifndef CONFIG_W25_READONLY
static void w25_pagewrite(struct w25_dev_s *priv, FAR const uint8_t *buffer,
off_t address, size_t nbytes)
{
uint8_t status;
fvdbg("address: %08lx nwords: %d\n", (long)address, (int)nbytes);
DEBUGASSERT(priv && buffer && (address & 0xff) == 0 &&
(nbytes & 0xff) == 0);
for (; nbytes > 0; nbytes -= W25_PAGE_SIZE)
{
/* Wait for any preceding write or erase operation to complete. */
status = w25_waitwritecomplete(priv);
DEBUGASSERT((status & (W25_SR_WEL|W25_SR_BP_MASK)) == 0);
/* Enable write access to the FLASH */
w25_wren(priv);
/* Select this FLASH part */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send the "Page Program (W25_PP)" Command */
SPI_SEND(priv->spi, W25_PP);
/* Send the address high byte first. */
(void)SPI_SEND(priv->spi, (address >> 16) & 0xff);
(void)SPI_SEND(priv->spi, (address >> 8) & 0xff);
(void)SPI_SEND(priv->spi, address & 0xff);
/* Then send the page of data */
SPI_SNDBLOCK(priv->spi, buffer, W25_PAGE_SIZE);
/* Deselect the FLASH and setup for the next pass through the loop */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
/* Update addresses */
address += W25_PAGE_SIZE;
buffer += W25_PAGE_SIZE;
}
/* Disable writing */
w25_wrdi(priv);
}
#endif
/************************************************************************************
* Name: w25_cacheflush
************************************************************************************/
#if defined(CONFIG_W25_SECTOR512) && !defined(CONFIG_W25_READONLY)
static void w25_cacheflush(struct w25_dev_s *priv)
{
/* If the cached is dirty (meaning that it no longer matches the old FLASH contents)
* or was erased (with the cache containing the correct FLASH contents), then write
* the cached erase block to FLASH.
*/
if (IS_DIRTY(priv) || IS_ERASED(priv))
{
/* Write entire erase block to FLASH */
w25_pagewrite(priv, priv->sector, (off_t)priv->esectno << W25_SECTOR_SHIFT,
W25_SECTOR_SIZE);
/* The case is no long dirty and the FLASH is no longer erased */
CLR_DIRTY(priv);
CLR_ERASED(priv);
}
}
#endif
/************************************************************************************
* Name: w25_cacheread
************************************************************************************/
#if defined(CONFIG_W25_SECTOR512) && !defined(CONFIG_W25_READONLY)
static FAR uint8_t *w25_cacheread(struct w25_dev_s *priv, off_t sector)
{
off_t esectno;
int shift;
int index;
/* Convert from the 512 byte sector to the erase sector size of the device. For
* exmample, if the actual erase sector size if 4Kb (1 << 12), then we first
* shift to the right by 3 to get the sector number in 4096 increments.
*/
shift = W25_SECTOR_SHIFT - W25_SECTOR512_SHIFT;
esectno = sector >> shift;
fvdbg("sector: %ld esectno: %d shift=%d\n", sector, esectno, shift);
/* Check if the requested erase block is already in the cache */
if (!IS_VALID(priv) || esectno != priv->esectno)
{
/* No.. Flush any dirty erase block currently in the cache */
w25_cacheflush(priv);
/* Read the erase block into the cache */
w25_byteread(priv, priv->sector, (esectno << W25_SECTOR_SHIFT), W25_SECTOR_SIZE);
/* Mark the sector as cached */
priv->esectno = esectno;
SET_VALID(priv); /* The data in the cache is valid */
CLR_DIRTY(priv); /* It should match the FLASH contents */
CLR_ERASED(priv); /* The underlying FLASH has not been erased */
}
/* Get the index to the 512 sector in the erase block that holds the argument */
index = sector & ((1 << shift) - 1);
/* Return the address in the cache that holds this sector */
return &priv->sector[index << W25_SECTOR512_SHIFT];
}
#endif
/************************************************************************************
* Name: w25_cacheerase
************************************************************************************/
#if defined(CONFIG_W25_SECTOR512) && !defined(CONFIG_W25_READONLY)
static void w25_cacheerase(struct w25_dev_s *priv, off_t sector)
{
FAR uint8_t *dest;
/* First, make sure that the erase block containing the 512 byte sector is in
* the cache.
*/
dest = w25_cacheread(priv, sector);
/* Erase the block containing this sector if it is not already erased.
* The erased indicated will be cleared when the data from the erase sector
* is read into the cache and set here when we erase the block.
*/
if (!IS_ERASED(priv))
{
off_t esectno = sector >> (W25_SECTOR_SHIFT - W25_SECTOR512_SHIFT);
fvdbg("sector: %ld esectno: %d\n", sector, esectno);
w25_sectorerase(priv, esectno);
SET_ERASED(priv);
}
/* Put the cached sector data into the erase state and mart the cache as dirty
* (but don't update the FLASH yet. The caller will do that at a more optimal
* time).
*/
memset(dest, W25_ERASED_STATE, W25_SECTOR512_SIZE);
SET_DIRTY(priv);
}
#endif
/************************************************************************************
* Name: w25_cachewrite
************************************************************************************/
#if defined(CONFIG_W25_SECTOR512) && !defined(CONFIG_W25_READONLY)
static void w25_cachewrite(FAR struct w25_dev_s *priv, FAR const uint8_t *buffer,
off_t sector, size_t nsectors)
{
FAR uint8_t *dest;
for (; nsectors > 0; nsectors--)
{
/* First, make sure that the erase block containing 512 byte sector is in
* memory.
*/
dest = w25_cacheread(priv, sector);
/* Erase the block containing this sector if it is not already erased.
* The erased indicated will be cleared when the data from the erase sector
* is read into the cache and set here when we erase the sector.
*/
if (!IS_ERASED(priv))
{
off_t esectno = sector >> (W25_SECTOR_SHIFT - W25_SECTOR512_SHIFT);
fvdbg("sector: %ld esectno: %d\n", sector, esectno);
w25_sectorerase(priv, esectno);
SET_ERASED(priv);
}
/* Copy the new sector data into cached erase block */
memcpy(dest, buffer, W25_SECTOR512_SIZE);
SET_DIRTY(priv);
/* Set up for the next 512 byte sector */
buffer += W25_SECTOR512_SIZE;
sector++;
}
/* Flush the last erase block left in the cache */
w25_cacheflush(priv);
}
#endif
/************************************************************************************
* Name: w25_erase
************************************************************************************/
static int w25_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks)
{
#ifdef CONFIG_W25_READONLY
return -EACESS
#else
FAR struct w25_dev_s *priv = (FAR struct w25_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 */
w25_lock(priv->spi);
while (blocksleft-- > 0)
{
/* Erase each sector */
#ifdef CONFIG_W25_SECTOR512
w25_cacheerase(priv, startblock);
#else
w25_sectorerase(priv, startblock);
#endif
startblock++;
}
#ifdef CONFIG_W25_SECTOR512
/* Flush the last erase block left in the cache */
w25_cacheflush(priv);
#endif
w25_unlock(priv->spi);
return (int)nblocks;
#endif
}
/************************************************************************************
* Name: w25_bread
************************************************************************************/
static ssize_t w25_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks,
FAR uint8_t *buffer)
{
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 */
#ifdef CONFIG_W25_SECTOR512
nbytes = w25_read(dev, startblock << W25_SECTOR512_SHIFT, nblocks << W25_SECTOR512_SHIFT, buffer);
if (nbytes > 0)
{
nbytes >>= W25_SECTOR512_SHIFT;
}
#else
nbytes = w25_read(dev, startblock << W25_SECTOR_SHIFT, nblocks << W25_SECTOR_SHIFT, buffer);
if (nbytes > 0)
{
nbytes >>= W25_SECTOR_SHIFT;
}
#endif
return nbytes;
}
/************************************************************************************
* Name: w25_bwrite
************************************************************************************/
static ssize_t w25_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks,
FAR const uint8_t *buffer)
{
#ifdef CONFIG_W25_READONLY
return -EACCESS;
#else
FAR struct w25_dev_s *priv = (FAR struct w25_dev_s *)dev;
fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* Lock the SPI bus and write all of the pages to FLASH */
w25_lock(priv->spi);
#if defined(CONFIG_W25_SECTOR512)
w25_cachewrite(priv, buffer, startblock, nblocks);
#else
w25_pagewrite(priv, buffer, startblock << W25_SECTOR_SHIFT,
nblocks << W25_SECTOR_SHIFT);
#endif
w25_unlock(priv->spi);
return nblocks;
#endif
}
/************************************************************************************
* Name: w25_read
************************************************************************************/
static ssize_t w25_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes,
FAR uint8_t *buffer)
{
FAR struct w25_dev_s *priv = (FAR struct w25_dev_s *)dev;
fvdbg("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes);
/* Lock the SPI bus and select this FLASH part */
w25_lock(priv->spi);
w25_byteread(priv, buffer, offset, nbytes);
w25_unlock(priv->spi);
fvdbg("return nbytes: %d\n", (int)nbytes);
return nbytes;
}
/************************************************************************************
* Name: w25_ioctl
************************************************************************************/
static int w25_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg)
{
FAR struct w25_dev_s *priv = (FAR struct w25_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.
*/
#ifdef CONFIG_W25_SECTOR512
geo->blocksize = (1 << W25_SECTOR512_SHIFT);
geo->erasesize = (1 << W25_SECTOR512_SHIFT);
geo->neraseblocks = priv->nsectors << (W25_SECTOR_SHIFT - W25_SECTOR512_SHIFT);
#else
geo->blocksize = W25_SECTOR_SIZE;
geo->erasesize = W25_SECTOR_SIZE;
geo->neraseblocks = priv->nsectors;
#endif
ret = OK;
fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n",
geo->blocksize, geo->erasesize, geo->neraseblocks);
}
}
break;
case MTDIOC_BULKERASE:
{
/* Erase the entire device */
w25_lock(priv->spi);
ret = w25_chiperase(priv);
w25_unlock(priv->spi);
}
break;
case MTDIOC_XIPBASE:
default:
ret = -ENOTTY; /* Bad command */
break;
}
fvdbg("return %d\n", ret);
return ret;
}
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: w25_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 *w25_initialize(FAR struct spi_dev_s *spi)
{
FAR struct w25_dev_s *priv;
int ret;
fvdbg("spi: %p\n", spi);
/* 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 w25_dev_s *)kzalloc(sizeof(struct w25_dev_s));
if (priv)
{
/* Initialize the allocated structure (unsupported methods were
* nullified by kzalloc).
*/
priv->mtd.erase = w25_erase;
priv->mtd.bread = w25_bread;
priv->mtd.bwrite = w25_bwrite;
priv->mtd.read = w25_read;
priv->mtd.ioctl = w25_ioctl;
priv->spi = spi;
/* Deselect the FLASH */
SPI_SELECT(spi, SPIDEV_FLASH, false);
/* Identify the FLASH chip and get its capacity */
ret = w25_readid(priv);
if (ret != OK)
{
/* Unrecognized! Discard all of that work we just did and return NULL */
fdbg("Unrecognized\n");
kfree(priv);
priv = NULL;
}
else
{
/* Make sure that the FLASH is unprotected so that we can write into it */
#ifndef CONFIG_W25_READONLY
w25_unprotect(priv);
#endif
#ifdef CONFIG_W25_SECTOR512 /* Simulate a 512 byte sector */
/* Allocate a buffer for the erase block cache */
priv->sector = (FAR uint8_t *)kmalloc(W25_SECTOR_SIZE);
if (!priv->sector)
{
/* Allocation failed! Discard all of that work we just did and return NULL */
fdbg("Allocation failed\n");
kfree(priv);
priv = NULL;
}
#endif
}
}
/* Register the MTD with the procfs system if enabled */
#ifdef CONFIG_MTD_REGISTRATION
mtd_register(&priv->mtd, "w25");
#endif
/* Return the implementation-specific state structure as the MTD device */
fvdbg("Return %p\n", priv);
return (FAR struct mtd_dev_s *)priv;
}