incubator-nuttx/drivers/mtd/mtd_progmem.c

456 lines
14 KiB
C

/****************************************************************************
* drivers/mtd/mtd_progmem.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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
#include <errno.h>
#include <nuttx/progmem.h>
#include <nuttx/fs/fs.h>
#include <nuttx/fs/ioctl.h>
#include <nuttx/mtd/mtd.h>
#ifdef CONFIG_MTD_PROGMEM
/****************************************************************************
* 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 progmem_dev_s.
*/
struct progmem_dev_s
{
/* Publicly visible representation of the interface */
struct mtd_dev_s mtd;
/* Fields unique to the progmem MTD driver */
bool initialized; /* True: Already initialized */
uint8_t blkshift; /* Log2 of the flash read/write block size */
uint8_t ersshift; /* Log2 of the flash erase block size */
};
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* Internal helper functions */
static int32_t progmem_log2(size_t blocksize);
/* MTD driver methods */
static int progmem_erase(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks);
static ssize_t progmem_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buf);
static ssize_t progmem_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buf);
static ssize_t progmem_read(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR uint8_t *buffer);
#ifdef CONFIG_MTD_BYTE_WRITE
static ssize_t progmem_write(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR const uint8_t *buffer);
#endif
static int progmem_ioctl(FAR struct mtd_dev_s *dev, int cmd,
unsigned long arg);
/****************************************************************************
* Private Data
****************************************************************************/
/* This structure holds the state of the MTD driver */
static struct progmem_dev_s g_progmem =
{
{
progmem_erase,
progmem_bread,
progmem_bwrite,
progmem_read,
#ifdef CONFIG_MTD_BYTE_WRITE
progmem_write,
#endif
progmem_ioctl,
NULL,
NULL,
"progmem",
}
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: progmem_log2
*
* Description:
* Check block size is exact powers of two.
*
****************************************************************************/
static int32_t progmem_log2(size_t blocksize)
{
uint32_t log2 = 0;
/* Search every bit in the blocksize from bit zero to bit 30 (omitting bit
* 31 which is the sign bit on return)
*/
for (log2 = 0; log2 < 31; log2++, blocksize >>= 1)
{
/* Is bit zero set? */
if ((blocksize & 1) != 0)
{
/* Yes... the value should be exactly one. We do not support
* block sizes that are not exact powers of two.
*/
return blocksize == 1 ? log2 : -ENOSYS;
}
}
return blocksize == 0 ? -EINVAL : -E2BIG;
}
/****************************************************************************
* Name: progmem_erase
*
* Description:
* Erase several blocks, each of the size previously reported.
*
****************************************************************************/
static int progmem_erase(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks)
{
ssize_t result;
/* Erase the specified blocks and return status (OK or a negated errno) */
while (nblocks > 0)
{
result = up_progmem_eraseblock(startblock);
if (result < 0)
{
return (int)result;
}
/* Setup for the next pass through the loop */
startblock++;
nblocks--;
}
return OK;
}
/****************************************************************************
* Name: progmem_bread
*
* Description:
* Read the specified number of blocks into the user provided buffer.
*
****************************************************************************/
static ssize_t progmem_bread(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR uint8_t *buffer)
{
FAR struct progmem_dev_s *priv = (FAR struct progmem_dev_s *)dev;
#ifdef CONFIG_ARCH_HAVE_PROGMEM_READ
ssize_t result;
result = up_progmem_read(up_progmem_getaddress(startblock), buffer,
nblocks << priv->blkshift);
return result < 0 ? result : nblocks;
#else
FAR const uint8_t *src;
/* Read the specified blocks into the provided user buffer and return
* status (The positive, number of blocks actually read or a negated
* errno).
*/
src = (FAR const uint8_t *)up_progmem_getaddress(startblock);
memcpy(buffer, src, nblocks << priv->blkshift);
return nblocks;
#endif
}
/****************************************************************************
* Name: progmem_bwrite
*
* Description:
* Write the specified number of blocks from the user provided buffer.
*
****************************************************************************/
static ssize_t progmem_bwrite(FAR struct mtd_dev_s *dev, off_t startblock,
size_t nblocks, FAR const uint8_t *buffer)
{
FAR struct progmem_dev_s *priv = (FAR struct progmem_dev_s *)dev;
ssize_t result;
/* Write the specified blocks from the provided user buffer and return
* status (The positive, number of blocks actually written or a negated
* errno)
*/
result = up_progmem_write(up_progmem_getaddress(startblock), buffer,
nblocks << priv->blkshift);
return result < 0 ? result : nblocks;
}
/****************************************************************************
* Name: progmem_read
*
* Description:
* Read the specified number of bytes to the user provided buffer.
*
****************************************************************************/
static ssize_t progmem_read(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR uint8_t *buffer)
{
FAR struct progmem_dev_s *priv = (FAR struct progmem_dev_s *)dev;
off_t startblock = offset >> priv->blkshift;
#ifdef CONFIG_ARCH_HAVE_PROGMEM_READ
ssize_t result;
result = up_progmem_read(up_progmem_getaddress(startblock) +
(offset & ((1 << priv->blkshift) - 1)), buffer, nbytes);
return result < 0 ? result : nbytes;
#else
FAR const uint8_t *src;
/* Read the specified bytes into the provided user buffer and return
* status (The positive, number of bytes actually read or a negated
* errno)
*/
src = (FAR const uint8_t *)up_progmem_getaddress(startblock) +
(offset & ((1 << priv->blkshift) - 1));
memcpy(buffer, src, nbytes);
return nbytes;
#endif
}
/****************************************************************************
* Name: progmem_write
*
* Description:
* Some FLASH parts have the ability to write an arbitrary number of
* bytes to an arbitrary offset on the device.
*
****************************************************************************/
#ifdef CONFIG_MTD_BYTE_WRITE
static ssize_t progmem_write(FAR struct mtd_dev_s *dev, off_t offset,
size_t nbytes, FAR const uint8_t *buffer)
{
FAR struct progmem_dev_s *priv = (FAR struct progmem_dev_s *)dev;
off_t startblock;
ssize_t result;
/* Write the specified blocks from the provided user buffer and return
* status (The positive number of blocks actually written or a negated
* errno).
*/
startblock = offset >> priv->blkshift;
result = up_progmem_write(up_progmem_getaddress(startblock) +
(offset & ((1 << priv->blkshift) - 1)), buffer, nbytes);
return result < 0 ? result : nbytes;
}
#endif
/****************************************************************************
* Name: progmem_ioctl
****************************************************************************/
static int progmem_ioctl(FAR struct mtd_dev_s *dev, int cmd,
unsigned long arg)
{
FAR struct progmem_dev_s *priv = (FAR struct progmem_dev_s *)dev;
int ret = -EINVAL; /* Assume good command with bad parameters */
switch (cmd)
{
case MTDIOC_GEOMETRY:
{
FAR struct mtd_geometry_s *geo = (FAR struct mtd_geometry_s *)arg;
if (geo)
{
memset(geo, 0, sizeof(*geo));
/* Populate the geometry structure with information needed 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->blkshift); /* Size of one read/write block */
geo->erasesize = (1 << priv->ersshift); /* Size of one erase block */
geo->neraseblocks = up_progmem_neraseblocks(); /* Number of erase blocks */
ret = OK;
}
}
break;
case BIOC_PARTINFO:
{
FAR struct partition_info_s *info =
(FAR struct partition_info_s *)arg;
if (info != NULL)
{
info->numsectors = up_progmem_neraseblocks() <<
(priv->ersshift - priv->blkshift);
info->sectorsize = 1 << priv->blkshift;
info->startsector = 0;
info->parent[0] = '\0';
ret = OK;
}
}
break;
case BIOC_XIPBASE:
{
FAR void **ppv = (FAR void**)arg;
if (ppv)
{
/* Return (void*) base address of FLASH memory. */
*ppv = (FAR void *)up_progmem_getaddress(0);
ret = OK;
}
}
break;
case MTDIOC_BULKERASE:
{
size_t nblocks = up_progmem_neraseblocks();
/* Erase the entire device */
ret = progmem_erase(dev, 0, nblocks);
}
break;
case MTDIOC_ERASESTATE:
{
FAR uint8_t *result = (FAR uint8_t *)arg;
*result = up_progmem_erasestate();
ret = OK;
}
break;
default:
ret = -ENOTTY; /* Bad command */
break;
}
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: progmem_initialize
*
* Description:
* Create and initialize an MTD device instance that can be used to access
* on-chip program memory.
*
* 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 *progmem_initialize(void)
{
FAR struct progmem_dev_s *priv = (FAR struct progmem_dev_s *)&g_progmem;
int32_t blkshift;
int32_t ersshift;
/* Perform initialization if necessary */
if (!g_progmem.initialized)
{
/* Get the size of one block. Here we assume that the block size is
* uniform and that the size of block0 is the same as the size of any
* other block.
*/
size_t blocksize = up_progmem_pagesize(0);
/* Calculate Log2 of the flash read/write block size */
blkshift = progmem_log2(blocksize);
if (blkshift < 0)
{
return NULL;
}
/* Calculate Log2 of the flash erase block size */
blocksize = up_progmem_erasesize(0);
ersshift = progmem_log2(blocksize);
if (ersshift < 0)
{
return NULL;
}
/* Save the configuration data */
g_progmem.blkshift = blkshift;
g_progmem.ersshift = ersshift;
g_progmem.initialized = true;
}
/* Return the implementation-specific state structure as the MTD device */
return (FAR struct mtd_dev_s *)priv;
}
#endif /* CONFIG_MTD_PROGMEM */