/****************************************************************************
* drivers/mtd/sector512.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/* MTD driver that contains another MTD driver and converts a larger sector
* size to a standard 512 byte sector size.
*/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <inttypes.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/mtd/mtd.h>
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration */
#ifndef CONFIG_MTD_SECT512_ERASED_STATE
# define CONFIG_MTD_SECT512_ERASED_STATE 0xff
#endif
/* 512-byte sector constants */
#define SECTOR_512 512
#define SHIFT_512 9
#define MASK_512 511
/* Cache flags */
#define SST25_CACHE_VALID (1 << 0) /* 1=Cache has valid data */
#define SST25_CACHE_DIRTY (1 << 1) /* 1=Cache is dirty */
#define SST25_CACHE_ERASED (1 << 2) /* 1=Backing FLASH is erased */
#define IS_VALID(p) ((((p)->flags) & SST25_CACHE_VALID) != 0)
#define IS_DIRTY(p) ((((p)->flags) & SST25_CACHE_DIRTY) != 0)
#define IS_ERASED(p) ((((p)->flags) & SST25_CACHE_DIRTY) != 0)
#define SET_VALID(p) do { (p)->flags |= SST25_CACHE_VALID; } while (0)
#define SET_DIRTY(p) do { (p)->flags |= SST25_CACHE_DIRTY; } while (0)
#define SET_ERASED(p) do { (p)->flags |= SST25_CACHE_DIRTY; } while (0)
#define CLR_VALID(p) do { (p)->flags &= ~SST25_CACHE_VALID; } while (0)
#define CLR_DIRTY(p) do { (p)->flags &= ~SST25_CACHE_DIRTY; } while (0)
#define CLR_ERASED(p) do { (p)->flags &= ~SST25_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 s512_dev_s.
*/
struct s512_dev_s
{
struct mtd_dev_s mtd; /* MTD interface */
FAR struct mtd_dev_s *dev; /* Saved lower level MTD interface instance */
uint32_t eblocksize; /* Size of one erase block */
size_t neblocks; /* Number of erase blocks */
size_t sectperblock; /* Number of read/write sectors per erase block */
uint16_t stdperblock; /* Number of 512 byte sectors in one erase block */
uint8_t flags; /* Buffered sector flags */
uint32_t eblockno; /* Erase sector number in the cache */
FAR uint8_t *eblock; /* Allocated erase block */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Helpers */
static FAR uint8_t *s512_cacheread(struct s512_dev_s *priv, off_t sector);
#ifndef CONFIG_MTD_SECT512_READONLY
static void s512_cacheflush(struct s512_dev_s *priv);
#endif
/* MTD driver methods */
static int s512_erase(FAR struct mtd_dev_s *dev,
off_t sector512,
size_t nsectors);
static ssize_t s512_bread(FAR struct mtd_dev_s *dev,
off_t sector512,
size_t nsectors,
FAR uint8_t *buf);
static ssize_t s512_bwrite(FAR struct mtd_dev_s *dev,
off_t sector512,
size_t nsectors,
FAR const uint8_t *buf);
static ssize_t s512_read(FAR struct mtd_dev_s *dev,
off_t offset,
size_t nbytes,
FAR uint8_t *buffer);
static int s512_ioctl(FAR struct mtd_dev_s *dev,
int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: s512_cacheread
****************************************************************************/
static FAR uint8_t *s512_cacheread(struct s512_dev_s *priv, off_t sector512)
{
off_t eblockno;
off_t sector;
ssize_t result;
int index;
/* Get the erase block containing this sector */
eblockno = sector512 / priv->stdperblock;
finfo("sector512: %lu eblockno: %lu\n",
(unsigned long)sector512, (unsigned long)eblockno);
/* Check if the requested erase block is already in the cache */
if (!IS_VALID(priv) || eblockno != priv->eblockno)
{
/* No.. Flush any dirty erase block currently in the cache */
s512_cacheflush(priv);
/* Read the erase block into the cache */
sector = eblockno * priv->sectperblock;
result = priv->dev->bread(priv->dev, sector, priv->sectperblock,
priv->eblock);
if (result < 0)
{
ferr("ERROR: bread(%lu, %lu) returned %ld\n",
(unsigned long)sector, (unsigned long)priv->eblocksize,
(long)result);
return NULL;
}
/* Mark the sector as cached */
priv->eblockno = eblockno;
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 = sector512 % priv->stdperblock;
/* Return the address in the cache that holds this sector */
return &priv->eblock[index << SHIFT_512];
}
/****************************************************************************
* Name: s512_cacheflush
****************************************************************************/
#if !defined(CONFIG_MTD_SECT512_READONLY)
static void s512_cacheflush(struct s512_dev_s *priv)
{
off_t sector;
ssize_t result;
/* 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 */
sector = priv->eblockno * priv->sectperblock;
result = priv->dev->bwrite(priv->dev, sector, priv->sectperblock,
priv->eblock);
if (result < 0)
{
ferr("ERROR: bwrite(%lu, %lu) returned %ld\n",
(unsigned long)sector, (unsigned long)priv->eblocksize,
(long)result);
return;
}
/* The cache is no long dirty and the FLASH is no longer erased */
CLR_DIRTY(priv);
CLR_ERASED(priv);
}
}
#endif
/****************************************************************************
* Name: s512_erase
****************************************************************************/
static int s512_erase(FAR struct mtd_dev_s *dev,
off_t sector512,
size_t nsectors)
{
#ifdef CONFIG_MTD_SECT512_READONLY
return -EACCES;
#else
FAR struct s512_dev_s *priv = (FAR struct s512_dev_s *)dev;
FAR uint8_t *dest;
size_t sectorsleft = nsectors;
size_t eblockno;
int ret;
finfo("sector512: %08jx nsectors: %zu\n", (intmax_t)sector512, nsectors);
while (sectorsleft-- > 0)
{
/* Erase each sector. First, make sure that the erase block containing
* the 512 byte sector is in the cache.
*/
dest = s512_cacheread(priv, sector512);
if (!dest)
{
ferr("ERROR: s512_cacheread(%lu) failed\n",
(unsigned long)sector512);
DEBUGPANIC();
return -EIO;
}
/* Erase the block containing this sector if it is not already erased.
* The erased indicator 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))
{
eblockno = sector512 / priv->stdperblock;
finfo("sector512: %lu eblockno: %lu\n",
(unsigned long)sector512, (unsigned long)eblockno);
ret = priv->dev->erase(priv->dev, eblockno, 1);
if (ret < 0)
{
ferr("ERROR: Failed to erase block %lu: %d\n",
(unsigned long)eblockno, ret);
return ret;
}
SET_ERASED(priv);
}
/* Put the cached sector data into the erase state and mark the cache
* as dirty (but don't update the FLASH yet. The caller will do that
* at a more optimal time).
*/
memset(dest, CONFIG_MTD_SECT512_ERASED_STATE, SECTOR_512);
SET_DIRTY(priv);
sector512++;
}
/* Flush the last erase block left in the cache */
s512_cacheflush(priv);
return (int)nsectors;
#endif
}
/****************************************************************************
* Name: s512_bread
****************************************************************************/
static ssize_t s512_bread(FAR struct mtd_dev_s *dev, off_t sector512,
size_t nsectors, FAR uint8_t *buffer)
{
FAR struct s512_dev_s *priv = (FAR struct s512_dev_s *)dev;
FAR uint8_t *src;
ssize_t remaining;
ssize_t result = nsectors;
finfo("sector512: %08lx nsectors: %d\n", (long)sector512, (int)nsectors);
/* Read each 512 byte sector from the block via the erase block cache */
for (remaining = nsectors; remaining; remaining--)
{
/* Make sure that the next sector is in the erase block cache */
src = s512_cacheread(priv, sector512);
if (!src)
{
ferr("ERROR: s512_cacheread(%lu) failed\n",
(unsigned long)sector512);
DEBUGPANIC();
result = (ssize_t)nsectors - remaining;
if (result <= 0)
{
result = -EIO;
}
break;
}
/* Copy the sector data from the erase block cache into the user
* buffer
*/
memcpy(buffer, src, SECTOR_512);
buffer += SECTOR_512;
sector512++;
}
return result;
}
/****************************************************************************
* Name: s512_bwrite
****************************************************************************/
static ssize_t s512_bwrite(FAR struct mtd_dev_s *dev, off_t sector512,
size_t nsectors,
FAR const uint8_t *buffer)
{
#ifdef CONFIG_MTD_SECT512_READONLY
return -EACCES;
#else
FAR struct s512_dev_s *priv = (FAR struct s512_dev_s *)dev;
ssize_t remaining;
ssize_t result;
off_t eblockno;
finfo("sector512: %08lx nsectors: %d\n", (long)sector512, (int)nsectors);
FAR uint8_t *dest;
for (remaining = nsectors; remaining > 0; remaining--)
{
/* First, make sure that the erase block containing 512 byte sector is
* in memory.
*/
dest = s512_cacheread(priv, sector512);
if (!dest)
{
result = (ssize_t)nsectors - remaining;
if (result <= 0)
{
result = -EIO;
}
return result;
}
/* 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))
{
eblockno = sector512 / priv->stdperblock;
finfo("sector512: %lu eblockno: %lu\n",
(unsigned long)sector512, (unsigned long)eblockno);
result = priv->dev->erase(priv->dev, eblockno, 1);
if (result < 0)
{
ferr("ERROR: Failed to erase block %lu: %ld\n",
(unsigned long)eblockno, (long)result);
return result;
}
SET_ERASED(priv);
}
/* Copy the new sector data into cached erase block */
memcpy(dest, buffer, SECTOR_512);
SET_DIRTY(priv);
/* Set up for the next 512 byte sector */
buffer += SECTOR_512;
sector512++;
}
/* Flush the last erase block left in the cache */
s512_cacheflush(priv);
return nsectors;
#endif
}
/****************************************************************************
* Name: s512_read
****************************************************************************/
static ssize_t s512_read(FAR struct mtd_dev_s *dev,
off_t offset,
size_t nbytes,
FAR uint8_t *buffer)
{
FAR struct s512_dev_s *priv = (FAR struct s512_dev_s *)dev;
FAR uint8_t *src;
ssize_t remaining;
ssize_t xfrsize;
off_t sectoffset;
off_t sector;
finfo("offset: %08lx nbytes: %lu\n",
(unsigned long)offset, (unsigned long)nbytes);
/* Convert the offset into 512 byte sector address and a byte offset */
sectoffset = offset & MASK_512;
sector = offset >> SHIFT_512;
for (remaining = nbytes; remaining > 0; remaining -= xfrsize)
{
/* Read the erase block into the cache and get the address of the
* beginning of the 512 byte block in the cached erase block.
*/
src = s512_cacheread(priv, sector);
if (!src)
{
int result;
ferr("ERROR: s512_cacheread(%lu) failed\n", (unsigned long)sector);
DEBUGPANIC();
result = (ssize_t)nbytes - remaining;
if (result <= 0)
{
result = -EIO;
}
return result;
}
/* Then copy the requested bytes from the cached erase block */
xfrsize = remaining;
if (sectoffset + xfrsize > SECTOR_512)
{
xfrsize = SECTOR_512 - sectoffset;
}
memcpy(buffer, src + sectoffset, xfrsize);
buffer += xfrsize;
}
finfo("return nbytes: %d\n", (int)nbytes);
return nbytes;
}
/****************************************************************************
* Name: s512_ioctl
****************************************************************************/
static int s512_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg)
{
FAR struct s512_dev_s *priv = (FAR struct s512_dev_s *)dev;
int ret = -EINVAL; /* Assume good command with bad parameters */
finfo("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)
{
memset(geo, 0, sizeof(*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 = SECTOR_512;
geo->erasesize = SECTOR_512;
geo->neraseblocks = priv->neblocks * priv->stdperblock;
ret = OK;
finfo("blocksize: %" PRId32 " erasesize: %" PRId32
" neraseblocks: %" PRId32 "\n",
geo->blocksize, geo->erasesize, geo->neraseblocks);
}
}
break;
case BIOC_PARTINFO:
{
FAR struct partition_info_s *info =
(FAR struct partition_info_s *)arg;
if (info != NULL)
{
info->numsectors = priv->neblocks * priv->stdperblock;
info->sectorsize = SECTOR_512;
info->startsector = 0;
info->parent[0] = '\0';
ret = OK;
}
}
break;
case MTDIOC_BULKERASE:
{
/* Erase the entire device */
ret = priv->dev->ioctl(priv->dev, MTDIOC_BULKERASE, 0);
if (ret >= 0)
{
priv->flags = 0; /* Buffered sector flags */
priv->eblockno = 0; /* Erase sector number in the cache */
priv->eblock = NULL; /* Allocated erase block */
}
}
break;
case MTDIOC_ERASESTATE:
{
FAR uint8_t *result = (FAR uint8_t *)arg;
*result = CONFIG_MTD_SECT512_ERASED_STATE;
ret = OK;
}
break;
default:
ret = -ENOTTY; /* Bad command */
break;
}
finfo("return %d\n", ret);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: s512_initialize
*
* Description:
* Create an initialized MTD device instance. This MTD driver contains
* another MTD driver and converts a larger sector size to a standard 512
* byte sector size.
*
* 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 *s512_initialize(FAR struct mtd_dev_s *mtd)
{
FAR struct s512_dev_s *priv;
FAR struct mtd_geometry_s geo;
int ret;
finfo("mtd: %p\n", mtd);
/* Get the device geometry */
DEBUGASSERT(mtd && mtd->ioctl);
ret = mtd->ioctl(mtd, MTDIOC_GEOMETRY, (unsigned long)((uintptr_t)&geo));
/* We expect that the block size will be >512 and an even multiple of 512 */
if (ret < 0 || geo.erasesize <= SECTOR_512 ||
(geo.erasesize & ~MASK_512) != geo.erasesize)
{
ferr(
"ERROR: MTDIOC_GEOMETRY ioctl returned %d, eraseize=%" PRId32 "\n",
ret, geo.erasesize);
DEBUGPANIC();
return NULL;
}
/* 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(0) definition) and so would
* have to be extended to handle multiple FLASH parts on the same SPI bus.
*/
priv = kmm_zalloc(sizeof(struct s512_dev_s));
if (priv)
{
/* Initialize the allocated structure. (unsupported methods/fields
* were already nullified by kmm_zalloc).
*/
priv->mtd.erase = s512_erase;
priv->mtd.bread = s512_bread;
priv->mtd.bwrite = s512_bwrite;
priv->mtd.read = s512_read;
priv->mtd.ioctl = s512_ioctl;
priv->mtd.name = "sector512";
priv->dev = mtd;
priv->eblocksize = geo.erasesize;
priv->neblocks = geo.neraseblocks;
priv->sectperblock = geo.erasesize / geo.blocksize;
priv->stdperblock = geo.erasesize >> 9;
/* Allocate a buffer for the erase block cache */
priv->eblock = kmm_malloc(priv->eblocksize);
if (!priv->eblock)
{
/* Allocation failed! Discard all of that work we just did and
* return NULL
*/
ferr("ERROR: Allocation failed\n");
kmm_free(priv);
priv = NULL;
}
}
/* Return the implementation-specific state structure as the MTD device */
finfo("Return %p\n", priv);
return &priv->mtd;
}