incubator-nuttx/drivers/mtd/mtd_progmem.c

426 lines
13 KiB
C

/****************************************************************************
* drivers/mtd/mtd_progmem.c
*
* Copyright (C) 2015, 2018 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 <string.h>
#include <errno.h>
#include <nuttx/progmem.h>
#include <nuttx/fs/ioctl.h>
#include <nuttx/mtd/mtd.h>
#ifdef CONFIG_ARCH_HAVE_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,
"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;
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;
}
/****************************************************************************
* 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;
FAR const uint8_t *src;
off_t startblock;
/* Read the specified bytes into the provided user buffer and return
* status (The positive, number of bytes actually read or a negated
* errno)
*/
startblock = offset >> priv->blkshift;
src = (FAR const uint8_t *)up_progmem_getaddress(startblock) +
(offset & ((1 << priv->blkshift) - 1));
memcpy(buffer, src, nbytes);
return nbytes;
}
/****************************************************************************
* 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)
{
/* 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 MTDIOC_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;
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_ARCH_HAVE_PROGMEM */