/**************************************************************************** * drivers/mtd/mtd_progmem.c * * Copyright (C) 2015 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * 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 #include #include #include #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * 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 { /* Publically 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 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 } }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: progmem_erase * * Description: * Erase several blocks, each of the size previously reported. * ****************************************************************************/ static int32_t progmem_log2(uint32_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_erasepage(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 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(offset); 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; 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(offset), 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->blkshift); /* Size of one erase block */ geo->neraseblocks = up_progmem_npages(); /* 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_npages(); /* 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; /* 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 block size */ blkshift = progmem_log2(blocksize); if (blkshift < 0) { return NULL; } /* Save the configuration data */ g_progmem.blkshift = blkshift; g_progmem.initialized = true; #ifdef CONFIG_MTD_REGISTRATION /* Register the MTD with the procfs system if enabled */ mtd_register(&priv->mtd, "progmem"); #endif } /* Return the implementation-specific state structure as the MTD device */ return (FAR struct mtd_dev_s *)priv; }