px4-firmware/nuttx/drivers/mtd/at45db.c

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/************************************************************************************
* drivers/mtd/at45db.c
* Driver for SPI-based AT45DB161D (16Mbit)
*
* Copyright (C) 2010-2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* 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.
*
************************************************************************************/
/* Ordering Code Detail:
*
* AT 45DB 16 1 D SS U
* | | | | | | `- Device grade
* | | | | | `- Package Option
* | | | | `- Device revision
* | | | `- Interface: 1=serial
* | | `- Capacity: 16=16Mbit
* | `- Product family
* `- Atmel designator
*/
/************************************************************************************
* Included Files
************************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <stdlib.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/arch.h>
#include <nuttx/ioctl.h>
#include <nuttx/spi.h>
#include <nuttx/mtd.h>
/************************************************************************************
* Pre-processor Definitions
************************************************************************************/
/* Configuration ********************************************************************/
/* CONFIG_AT45DB_PREWAIT enables higher performance write logic: We leave the chip
* busy after write and erase operations. This improves write and erase performance
* because we do not have to wait as long between transactions (other processing can
* occur while the chip is busy) but means that the chip must stay powered:
*/
#if defined(CONFIG_AT45DB_PWRSAVE) && defined(CONFIG_AT45DB_PREWAIT)
# error "Both CONFIG_AT45DB_PWRSAVE and CONFIG_AT45DB_PREWAIT are defined"
#endif
/* If the user has provided no frequency, use 1MHz */
#ifndef CONFIG_AT45DB_FREQUENCY
# define CONFIG_AT45DB_FREQUENCY 1000000
#endif
/* SPI Commands *********************************************************************/
/* Read commands */
#define AT45DB_RDMN 0xd2 /* Main Memory Page Read */
#define AT45DB_RDARRY 0xe8 /* Continuous Array Read (Legacy Command) */
#define AT45DB_RDARRAYLF 0x03 /* Continuous Array Read (Low Frequency) */
#define AT45DB_RDARRAYHF 0x0b /* Continuous Array Read (High Frequency) */
#define AT45DB_RDBF1LF 0xd1 /* Buffer 1 Read (Low Frequency) */
#define AT45DB_RDBF2LF 0xd3 /* Buffer 2 Read (Low Frequency) */
#define AT45DB_RDBF1 0xd4 /* Buffer 1 Read */
#define AT45DB_RDBF2 0xd6 /* Buffer 2 Read */
/* Program and Erase Commands */
#define AT45DB_WRBF1 0x84 /* Buffer 1 Write */
#define AT45DB_WRBF2 0x87 /* Buffer 2 Write */
#define AT45DB_BF1TOMNE 0x83 /* Buffer 1 to Main Memory Page Program with Built-in Erase */
#define AT45DB_BF2TOMNE 0x86 /* Buffer 2 to Main Memory Page Program with Built-in Erase */
#define AT45DB_BF1TOMN 0x88 /* Buffer 1 to Main Memory Page Program without Built-in Erase */
#define AT45DB_BF2TOMN 0x89 /* Buffer 2 to Main Memory Page Program without Built-in Erase */
#define AT45DB_PGERASE 0x81 /* Page Erase */
#define AT45DB_BLKERASE 0x50 /* Block Erase */
#define AT45DB_SECTERASE 0x7c /* Sector Erase */
#define AT45DB_CHIPERASE1 0xc7 /* Chip Erase - byte 1 */
# define AT45DB_CHIPERASE2 0x94 /* Chip Erase - byte 2 */
# define AT45DB_CHIPERASE3 0x80 /* Chip Erase - byte 3 */
# define AT45DB_CHIPERASE4 0x9a /* Chip Erase - byte 4 */
#define AT45DB_MNTHRUBF1 0x82 /* Main Memory Page Program Through Buffer 1 */
#define AT45DB_MNTHRUBF2 0x85 /* Main Memory Page Program Through Buffer 2 */
/* Protection and Security Commands */
#define AT45DB_ENABPROT1 0x3d /* Enable Sector Protection - byte 1 */
# define AT45DB_ENABPROT2 0x2a /* Enable Sector Protection - byte 2 */
# define AT45DB_ENABPROT3 0x7f /* Enable Sector Protection - byte 3 */
# define AT45DB_ENABPROT4 0xa9 /* Enable Sector Protection - byte 4 */
#define AT45DB_DISABPROT1 0x3d /* Disable Sector Protection - byte 1 */
# define AT45DB_DISABPROT2 0x2a /* Disable Sector Protection - byte 2 */
# define AT45DB_DISABPROT3 0x7f /* Disable Sector Protection - byte 3 */
# define AT45DB_DISABPROT4 0x9a /* Disable Sector Protection - byte 4 */
#define AT45DB_ERASEPROT1 0x3d /* Erase Sector Protection Register - byte 1 */
# define AT45DB_ERASEPROT2 0x2a /* Erase Sector Protection Register - byte 2 */
# define AT45DB_ERASEPROT3 0x7f /* Erase Sector Protection Register - byte 3 */
# define AT45DB_ERASEPROT4 0xcf /* Erase Sector Protection Register - byte 4 */
#define AT45DB_PROGPROT1 0x3d /* Program Sector Protection Register - byte 1 */
# define AT45DB_PROGPROT2 0x2a /* Program Sector Protection Register - byte 2 */
# define AT45DB_PROGPROT3 0x7f /* Program Sector Protection Register - byte 3 */
# define AT45DB_PROGPROT4 0xfc /* Program Sector Protection Register - byte 4 */
#define AT45DB_RDPROT 0x32 /* Read Sector Protection Register */
#define AT45DB_LOCKDOWN1 0x3d /* Sector Lockdown - byte 1 */
# define AT45DB_LOCKDOWN2 0x2a /* Sector Lockdown - byte 2 */
# define AT45DB_LOCKDOWN3 0x7f /* Sector Lockdown - byte 3 */
# define AT45DB_LOCKDOWN4 0x30 /* Sector Lockdown - byte 4 */
#define AT45DB_RDLOCKDOWN 0x35 /* Read Sector Lockdown Register */
#define AT45DB_PROGSEC1 0x9b /* Program Security Register - byte 1 */
# define AT45DB_PROGSEC2 0x00 /* Program Security Register - byte 2 */
# define AT45DB_PROGSEC3 0x00 /* Program Security Register - byte 3 */
# define AT45DB_PROGSEC4 0x00 /* Program Security Register - byte 4 */
#define AT45DB_RDSEC 0x77 /* Read Security Register */
/* Additional commands */
#define AT45DB_MNTOBF1XFR 0x53 /* Main Memory Page to Buffer 1 Transfer */
#define AT45DB_MNTOBF2XFR 0x55 /* Main Memory Page to Buffer 2 Transfer */
#define AT45DB_MNBF1CMP 0x60 /* Main Memory Page to Buffer 1 Compare */
#define AT45DB_MNBF2CMP 0x61 /* Main Memory Page to Buffer 2 Compare */
#define AT45DB_AUTOWRBF1 0x58 /* Auto Page Rewrite through Buffer 1 */
#define AT45DB_AUTOWRBF2 0x59 /* Auto Page Rewrite through Buffer 2 */
#define AT45DB_PWRDOWN 0xb9 /* Deep Power-down */
#define AT45DB_RESUME 0xab /* Resume from Deep Power-down */
#define AT45DB_RDSR 0xd7 /* Status Register Read */
#define AT45DB_RDDEVID 0x9f /* Manufacturer and Device ID Read */
#define AT45DB_MANUFACTURER 0x1f /* Manufacturer ID: Atmel */
#define AT45DB_DEVID1_CAPMSK 0x1f /* Bits 0-4: Capacity */
#define AT45DB_DEVID1_1MBIT 0x02 /* xxx0 0010 = 1Mbit AT45DB011 */
#define AT45DB_DEVID1_2MBIT 0x03 /* xxx0 0012 = 2Mbit AT45DB021 */
#define AT45DB_DEVID1_4MBIT 0x04 /* xxx0 0100 = 4Mbit AT45DB041 */
#define AT45DB_DEVID1_8MBIT 0x05 /* xxx0 0101 = 8Mbit AT45DB081 */
#define AT45DB_DEVID1_16MBIT 0x06 /* xxx0 0110 = 16Mbit AT45DB161 */
#define AT45DB_DEVID1_32MBIT 0x07 /* xxx0 0111 = 32Mbit AT45DB321 */
#define AT45DB_DEVID1_64MBIT 0x08 /* xxx0 1000 = 32Mbit AT45DB641 */
#define AT45DB_DEVID1_FAMMSK 0xe0 /* Bits 5-7: Family */
#define AT45DB_DEVID1_DFLASH 0x20 /* 001x xxxx = Dataflash */
#define AT45DB_DEVID1_AT26DF 0x40 /* 010x xxxx = AT26DFxxx series (Not supported) */
#define AT45DB_DEVID2_VERMSK 0x1f /* Bits 0-4: MLC mask */
#define AT45DB_DEVID2_MLCMSK 0xe0 /* Bits 5-7: MLC mask */
/* Status register bit definitions */
#define AT45DB_SR_RDY (1 << 7) /* Bit 7: RDY/ Not BUSY */
#define AT45DB_SR_COMP (1 << 6) /* Bit 6: COMP */
#define AT45DB_SR_PROTECT (1 << 1) /* Bit 1: PROTECT */
#define AT45DB_SR_PGSIZE (1 << 0) /* Bit 0: PAGE_SIZE */
/* 1 Block = 16 pages; 1 sector = 256 pages */
#define PG_PER_BLOCK (16)
#define PG_PER_SECTOR (256)
/************************************************************************************
* 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 at45db_dev_s.
*/
struct at45db_dev_s
{
struct mtd_dev_s mtd; /* MTD interface */
FAR struct spi_dev_s *spi; /* Saved SPI interface instance */
uint8_t pageshift; /* log2 of the page size (eg. 1 << 9 = 512) */
uint32_t npages; /* Number of pages in the device */
};
/************************************************************************************
* Private Function Prototypes
************************************************************************************/
/* Lock and per-transaction configuration */
static void at45db_lock(struct at45db_dev_s *priv);
static inline void at45db_unlock(struct at45db_dev_s *priv);
/* Power management */
#ifdef CONFIG_AT45DB_PWRSAVE
static void at45db_pwrdown(struct at45db_dev_s *priv);
static void at45db_resume(struct at45db_dev_s *priv);
#else
# define at45db_pwrdown(priv)
# define at45db_resume(priv)
#endif
/* Low-level AT45DB Helpers */
static inline int at45db_rdid(struct at45db_dev_s *priv);
static inline uint8_t at45db_rdsr(struct at45db_dev_s *priv);
static uint8_t at45db_waitbusy(struct at45db_dev_s *priv);
static inline void at45db_pgerase(struct at45db_dev_s *priv, off_t offset);
static inline int at32db_chiperase(struct at45db_dev_s *priv);
static inline void at45db_pgwrite(struct at45db_dev_s *priv, FAR const uint8_t *buffer,
off_t offset);
/* MTD driver methods */
static int at45db_erase(FAR struct mtd_dev_s *mtd, off_t startblock, size_t nblocks);
static ssize_t at45db_bread(FAR struct mtd_dev_s *mtd, off_t startblock,
size_t nblocks, FAR uint8_t *buf);
static ssize_t at45db_bwrite(FAR struct mtd_dev_s *mtd, off_t startblock,
size_t nblocks, FAR const uint8_t *buf);
static ssize_t at45db_read(FAR struct mtd_dev_s *mtd, off_t offset, size_t nbytes,
FAR uint8_t *buffer);
static int at45db_ioctl(FAR struct mtd_dev_s *mtd, int cmd, unsigned long arg);
/************************************************************************************
* Private Data
************************************************************************************/
/* Chip erase sequence */
#define CHIP_ERASE_SIZE 4
static const uint8_t g_chiperase[CHIP_ERASE_SIZE] = {0xc7, 0x94, 0x80, 0x9a};
/* Sequence to program the device to binary page sizes{256, 512, 1024} */
#define BINPGSIZE_SIZE 4
static const uint8_t g_binpgsize[BINPGSIZE_SIZE] = {0x3d, 0x2a, 0x80, 0xa6};
/************************************************************************************
* Private Functions
************************************************************************************/
/************************************************************************************
* Name: at45db_lock
************************************************************************************/
static void at45db_lock(struct at45db_dev_s *priv)
{
/* 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.
*/
SPI_LOCK(priv->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(priv->spi, SPIDEV_MODE0);
SPI_SETBITS(priv->spi, 8);
(void)SPI_SETFREQUENCY(priv->spi, CONFIG_AT45DB_FREQUENCY);
}
/************************************************************************************
* Name: at45db_unlock
************************************************************************************/
static inline void at45db_unlock(struct at45db_dev_s *priv)
{
SPI_LOCK(priv->spi, false);
}
/************************************************************************************
* Name: at45db_pwrdown
************************************************************************************/
#ifdef CONFIG_AT45DB_PWRSAVE
static void at45db_pwrdown(struct at45db_dev_s *priv)
{
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SEND(priv->spi, AT45DB_PWRDOWN);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
}
#endif
/************************************************************************************
* Name: at45db_resume
************************************************************************************/
#ifdef CONFIG_AT45DB_PWRSAVE
static void at45db_resume(struct at45db_dev_s *priv)
{
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SEND(priv->spi, AT45DB_RESUME);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
up_udelay(50);
}
#endif
/************************************************************************************
* Name: at45db_rdid
************************************************************************************/
static inline int at45db_rdid(struct at45db_dev_s *priv)
{
uint8_t capacity;
uint8_t devid[3];
fvdbg("priv: %p\n", priv);
/* Configure the bus, and select this FLASH part. (The caller should alread have
* loced the bus for exclusive access)
*/
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
/* Send the " Manufacturer and Device ID Read" command and read the next three
* ID bytes from the FLASH.
*/
(void)SPI_SEND(priv->spi, AT45DB_RDDEVID);
SPI_RECVBLOCK(priv->spi, devid, 3);
/* Deselect the FLASH */
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
fvdbg("manufacturer: %02x devid1: %02x devid2: %02x\n",
devid[0], devid[1], devid[2]);
/* Check for a valid manufacturer and memory family */
if (devid[0] == AT45DB_MANUFACTURER &&
(devid[1] & AT45DB_DEVID1_FAMMSK) == AT45DB_DEVID1_DFLASH)
{
/* Okay.. is it a FLASH capacity that we understand? */
capacity = devid[1] & AT45DB_DEVID1_CAPMSK;
switch (capacity)
{
case AT45DB_DEVID1_1MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB011 */
priv->pageshift = 8; /* Page size = 256 bytes */
priv->npages = 512; /* 512 pages */
return OK;
case AT45DB_DEVID1_2MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB021 */
priv->pageshift = 8; /* Page size = 256/264 bytes */
priv->npages = 1024; /* 1024 pages */
return OK;
case AT45DB_DEVID1_4MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB041 */
priv->pageshift = 8; /* Page size = 256/264 bytes */
priv->npages = 2048; /* 2048 pages */
return OK;
case AT45DB_DEVID1_8MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB081 */
priv->pageshift = 8; /* Page size = 256/264 bytes */
priv->npages = 4096; /* 4096 pages */
return OK;
case AT45DB_DEVID1_16MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB161 */
priv->pageshift = 9; /* Page size = 512/528 bytes */
priv->npages = 4096; /* 4096 pages */
return OK;
case AT45DB_DEVID1_32MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB321 */
priv->pageshift = 9; /* Page size = 512/528 bytes */
priv->npages = 8192; /* 8192 pages */
return OK;
case AT45DB_DEVID1_64MBIT:
/* Save the FLASH geometry for the 16Mbit AT45DB321 */
priv->pageshift = 10; /* Page size = 1024/1056 bytes */
priv->npages = 8192; /* 8192 pages */
return OK;
default:
return -ENODEV;
}
}
return -ENODEV;
}
/************************************************************************************
* Name: at45db_rdsr
************************************************************************************/
static inline uint8_t at45db_rdsr(struct at45db_dev_s *priv)
{
uint8_t retval;
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SEND(priv->spi, AT45DB_RDSR);
retval = SPI_SEND(priv->spi, 0xff);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
return retval;
}
/************************************************************************************
* Name: at45db_waitbusy
************************************************************************************/
static uint8_t at45db_waitbusy(struct at45db_dev_s *priv)
{
uint8_t sr;
/* Poll the device, waiting for it to report that it is ready */
do
{
up_udelay(10);
sr = (uint8_t)at45db_rdsr(priv);
}
while ((sr & AT45DB_SR_RDY) == 0);
return sr;
}
/************************************************************************************
* Name: at45db_pgerase
************************************************************************************/
static inline void at45db_pgerase(struct at45db_dev_s *priv, off_t sector)
{
uint8_t erasecmd[4];
off_t offset = sector << priv->pageshift;
fvdbg("sector: %08lx\n", (long)sector);
/* Higher performance write logic: We leave the chip busy after write and erase
* operations. This improves write and erase performance because we do not have
* to wait as long between transactions (other processing can occur while the chip
* is busy) but means that the chip must stay powered and that we must check if
* the chip is still busy on each entry point.
*/
#ifdef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
/* "The Page Erase command can be used to individually erase any page in the main
* memory array allowing the Buffer to Main Memory Page Program to be utilized at a
* later time. ... To perform a page erase in the binary page size ..., the
* opcode 81H must be loaded into the device, followed by three address bytes
* ... When a low-to-high transition occurs on the CS pin, the part will erase the
* selected page (the erased state is a logical 1). ... the status register and the
* RDY/BUSY pin will indicate that the part is busy."
*/
erasecmd[0] = AT45DB_PGERASE; /* Page erase command */
erasecmd[1] = (offset >> 16) & 0xff; /* 24-bit offset MS bytes */
erasecmd[2] = (offset >> 8) & 0xff; /* 24-bit offset middle bytes */
erasecmd[3] = offset & 0xff; /* 24-bit offset LS bytes */
/* Erase the page */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SNDBLOCK(priv->spi, erasecmd, 4);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
/* Wait for any erase to complete if we are not trying to improve write
* performance. (see comments above).
*/
#ifndef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
fvdbg("Erased\n");
}
/************************************************************************************
* Name: at32db_chiperase
************************************************************************************/
static inline int at32db_chiperase(struct at45db_dev_s *priv)
{
fvdbg("priv: %p\n", priv);
/* Higher performance write logic: We leave the chip busy after write and erase
* operations. This improves write and erase performance because we do not have
* to wait as long between transactions (other processing can occur while the chip
* is busy) but means that the chip must stay powered and that we must check if
* the chip is still busy on each entry point.
*/
#ifdef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
/* "The entire main memory can be erased at one time by using the Chip Erase
* command. To execute the Chip Erase command, a 4-byte command sequence C7H, 94H,
* 80H and 9AH must be clocked into the device. ... After the last bit of the opcode
* sequence has been clocked in, the CS pin can be deasserted to start the erase
* process. ... the Status Register will indicate that the device is busy. The Chip
* Erase command will not affect sectors that are protected or locked down...
*/
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SNDBLOCK(priv->spi, g_chiperase, CHIP_ERASE_SIZE);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
/* Wait for any erase to complete if we are not trying to improve write
* performance. (see comments above).
*/
#ifndef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
return OK;
}
/************************************************************************************
* Name: at45db_pgwrite
************************************************************************************/
static inline void at45db_pgwrite(struct at45db_dev_s *priv, FAR const uint8_t *buffer,
off_t page)
{
uint8_t wrcmd [4];
off_t offset = page << priv->pageshift;
fvdbg("page: %08lx offset: %08lx\n", (long)page, (long)offset);
/* We assume that sectors are not write protected */
wrcmd[0] = AT45DB_MNTHRUBF1; /* To main memory through buffer 1 */
wrcmd[1] = (offset >> 16) & 0xff; /* 24-bit address MS byte */
wrcmd[2] = (offset >> 8) & 0xff; /* 24-bit address middle byte */
wrcmd[3] = offset & 0xff; /* 24-bit address LS byte */
/* Higher performance write logic: We leave the chip busy after write and erase
* operations. This improves write and erase performance because we do not have
* to wait as long between transactions (other processing can occur while the chip
* is busy) but means that the chip must stay powered and that we must check if
* the chip is still busy on each entry point.
*/
#ifdef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SNDBLOCK(priv->spi, wrcmd, 4);
SPI_SNDBLOCK(priv->spi, buffer, 1 << priv->pageshift);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
/* Wait for any erase to complete if we are not trying to improve write
* performance. (see comments above).
*/
#ifndef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
fvdbg("Written\n");
}
/************************************************************************************
* Name: at45db_erase
************************************************************************************/
static int at45db_erase(FAR struct mtd_dev_s *mtd, off_t startblock, size_t nblocks)
{
FAR struct at45db_dev_s *priv = (FAR struct at45db_dev_s *)mtd;
size_t pgsleft = nblocks;
fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* Take the lock so that we have exclusive access to the bus, then power up the
* FLASH device.
*/
at45db_lock(priv);
at45db_resume(priv);
/* Then erase each page */
while (pgsleft-- > 0)
{
/* Erase each sector */
at45db_pgerase(priv, startblock);
startblock++;
}
at45db_pwrdown(priv);
at45db_unlock(priv);
return (int)nblocks;
}
/************************************************************************************
* Name: at45db_bread
************************************************************************************/
static ssize_t at45db_bread(FAR struct mtd_dev_s *mtd, off_t startblock, size_t nblocks,
FAR uint8_t *buffer)
{
FAR struct at45db_dev_s *priv = (FAR struct at45db_dev_s *)mtd;
ssize_t nbytes;
/* On this device, we can handle the block read just like the byte-oriented read */
nbytes = at45db_read(mtd, startblock << priv->pageshift, nblocks << priv->pageshift, buffer);
if (nbytes > 0)
{
return nbytes >> priv->pageshift;
}
return nbytes;
}
/************************************************************************************
* Name: at45db_bwrite
************************************************************************************/
static ssize_t at45db_bwrite(FAR struct mtd_dev_s *mtd, off_t startblock, size_t nblocks,
FAR const uint8_t *buffer)
{
FAR struct at45db_dev_s *priv = (FAR struct at45db_dev_s *)mtd;
size_t pgsleft = nblocks;
fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks);
/* Take the lock so that we have exclusive access to the bus, then power up the
* FLASH device.
*/
at45db_lock(priv);
at45db_resume(priv);
/* Write each page to FLASH */
while (pgsleft-- > 0)
{
at45db_pgwrite(priv, buffer, startblock);
startblock++;
}
at45db_pwrdown(priv);
at45db_unlock(priv);
return nblocks;
}
/************************************************************************************
* Name: at45db_read
************************************************************************************/
static ssize_t at45db_read(FAR struct mtd_dev_s *mtd, off_t offset, size_t nbytes,
FAR uint8_t *buffer)
{
FAR struct at45db_dev_s *priv = (FAR struct at45db_dev_s *)mtd;
uint8_t rdcmd [5];
fvdbg("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes);
/* Set up for the read */
rdcmd[0] = AT45DB_RDARRAYHF; /* FAST_READ is safe at all supported SPI speeds. */
rdcmd[1] = (offset >> 16) & 0xff; /* 24-bit address upper byte */
rdcmd[2] = (offset >> 8) & 0xff; /* 24-bit address middle byte */
rdcmd[3] = offset & 0xff; /* 24-bit address least significant byte */
rdcmd[4] = 0; /* Dummy byte */
/* Take the lock so that we have exclusive access to the bus, then power up the
* FLASH device.
*/
at45db_lock(priv);
at45db_resume(priv);
/* Higher performance write logic: We leave the chip busy after write and erase
* operations. This improves write and erase performance because we do not have
* to wait as long between transactions (other processing can occur while the chip
* is busy) but means that the chip must stay powered and that we must check if
* the chip is still busy on each entry point.
*/
#ifdef CONFIG_AT45DB_PREWAIT
at45db_waitbusy(priv);
#endif
/* Perform the read */
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SNDBLOCK(priv->spi, rdcmd, 5);
SPI_RECVBLOCK(priv->spi, buffer, nbytes);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
at45db_pwrdown(priv);
at45db_unlock(priv);
fvdbg("return nbytes: %d\n", (int)nbytes);
return nbytes;
}
/************************************************************************************
* Name: at45db_ioctl
************************************************************************************/
static int at45db_ioctl(FAR struct mtd_dev_s *mtd, int cmd, unsigned long arg)
{
FAR struct at45db_dev_s *priv = (FAR struct at45db_dev_s *)mtd;
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 = geo->blocksize;
geo->neraseblocks = priv->npages;
ret = OK;
fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n",
geo->blocksize, geo->erasesize, geo->neraseblocks);
}
}
break;
case MTDIOC_BULKERASE:
{
/* Take the lock so that we have exclusive access to the bus, then
* power up the FLASH device.
*/
at45db_lock(priv);
at45db_resume(priv);
/* Erase the entire device */
ret = at32db_chiperase(priv);
at45db_pwrdown(priv);
at45db_unlock(priv);
}
break;
case MTDIOC_XIPBASE:
default:
ret = -ENOTTY; /* Bad command */
break;
}
fvdbg("return %d\n", ret);
return ret;
}
/************************************************************************************
* Public Functions
************************************************************************************/
/************************************************************************************
* Name: at45db_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 *at45db_initialize(FAR struct spi_dev_s *spi)
{
FAR struct at45db_dev_s *priv;
uint8_t sr;
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 at45db_dev_s *)kmalloc(sizeof(struct at45db_dev_s));
if (priv)
{
/* Initialize the allocated structure */
priv->mtd.erase = at45db_erase;
priv->mtd.bread = at45db_bread;
priv->mtd.bwrite = at45db_bwrite;
priv->mtd.read = at45db_read;
priv->mtd.ioctl = at45db_ioctl;
priv->spi = spi;
/* Deselect the FLASH */
SPI_SELECT(spi, SPIDEV_FLASH, false);
/* Lock and configure the SPI bus. */
at45db_lock(priv);
at45db_resume(priv);
/* Identify the FLASH chip and get its capacity */
ret = at45db_rdid(priv);
if (ret != OK)
{
/* Unrecognized! Discard all of that work we just did and return NULL */
fdbg("Unrecognized\n");
goto errout;
}
/* Get the value of the status register (as soon as the device is ready) */
sr = at45db_waitbusy(priv);
/* Check if the device is configured as 256, 512 or 1024 bytes-per-page device */
if ((sr & AT45DB_SR_PGSIZE) == 0)
{
/* No, re-program it for the binary page size. NOTE: A power cycle
* is required after the device has be re-programmed.
*/
fdbg("Reprogramming page size\n");
SPI_SELECT(priv->spi, SPIDEV_FLASH, true);
SPI_SNDBLOCK(priv->spi, g_binpgsize, BINPGSIZE_SIZE);
SPI_SELECT(priv->spi, SPIDEV_FLASH, false);
goto errout;
}
/* Release the lock and power down the device */
at45db_pwrdown(priv);
at45db_unlock(priv);
}
fvdbg("Return %p\n", priv);
return (FAR struct mtd_dev_s *)priv;
/* On any failure, we need free memory allocations and release the lock that
* we hold on the SPI bus. On failures, assume that we cannot talk to the
* device to do any more.
*/
errout:
at45db_unlock(priv);
kfree(priv);
return NULL;
}