/************************************************************************************ * drivers/mtd/mtd_rwbuffer.c * MTD driver that contains another MTD driver and provides read-ahead and/or write * buffering. * * Copyright (C) 2014 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 #include #include #include #include #if defined(CONFIG_DRVR_WRITEBUFFER) || defined(CONFIG_DRVR_READAHEAD) /************************************************************************************ * Pre-processor Definitions ************************************************************************************/ #ifndef CONFIG_DRVR_INVALIDATE # error This driver requires CONFIG_DRVR_INVALIDATE #endif #ifndef CONFIG_DRVR_READBYTES # error This driver requires CONFIG_DRVR_READBYTES #endif #ifndef CONFIG_MTD_NWRBLOCKS # define CONFIG_MTD_NWRBLOCKS 4 #endif #ifndef CONFIG_MTD_NRDBLOCKS # define CONFIG_MTD_NRDBLOCKS 4 #endif /************************************************************************************ * 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 mtd_rwbuffer_s. */ struct mtd_rwbuffer_s { struct mtd_dev_s mtd; /* Our exported MTD interface */ FAR struct mtd_dev_s *dev; /* Saved lower level MTD interface instance */ struct rwbuffer_s rwb; /* The rwbuffer state structure */ uint16_t spb; /* Number of sectors per block */ }; /************************************************************************************ * Private Function Prototypes ************************************************************************************/ /* rwbuffer callouts */ static ssize_t mtd_reload(FAR void *dev, FAR uint8_t *buffer, off_t startblock, size_t nblocks); static ssize_t mtd_flush(FAR void *dev, FAR const uint8_t *buffer, off_t startblock, size_t nblocks); /* MTD driver methods */ static int mtd_erase(FAR struct mtd_dev_s *dev, off_t block, size_t nsectors); static ssize_t mtd_bread(FAR struct mtd_dev_s *dev, off_t block, size_t nsectors, FAR uint8_t *buf); static ssize_t mtd_bwrite(FAR struct mtd_dev_s *dev, off_t block, size_t nsectors, FAR const uint8_t *buf); static ssize_t mtd_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, FAR uint8_t *buffer); static int mtd_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg); /************************************************************************************ * Private Data ************************************************************************************/ /************************************************************************************ * Private Functions ************************************************************************************/ /************************************************************************************ * Name: mtd_reload * * Description: * Reload the read-ahead buffer * ************************************************************************************/ static ssize_t mtd_reload(FAR void *dev, FAR uint8_t *buffer, off_t startblock, size_t nblocks) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_s *)dev; DEBUGASSERT(priv && priv->dev); /* This is just a pass-through to the contained MTD */ return priv->dev->bread(priv->dev, startblock, nblocks, buffer); } /************************************************************************************ * Name: mtd_flush * * Description: * Flush the write buffer to hardware * ************************************************************************************/ static ssize_t mtd_flush(FAR void *dev, FAR const uint8_t *buffer, off_t startblock, size_t nblocks) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_s *)dev; DEBUGASSERT(priv && priv->dev); /* This is just a pass-through to the contained MTD */ return priv->dev->bwrite(priv->dev, startblock, nblocks, buffer); } /************************************************************************************ * Name: mtd_erase ************************************************************************************/ static int mtd_erase(FAR struct mtd_dev_s *dev, off_t block, size_t nblocks) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_s *)dev; off_t sector; size_t nsectors; int ret; finfo("block: %08lx nsectors: %lu\n", (unsigned long)block, (unsigned int)nsectors); /* Convert to logical sectors and sector numbers */ sector = block * priv->spb; nsectors = nblocks * priv->spb; /* Then invalidate in cached data */ ret = rwb_invalidate(&priv->rwb, sector, nsectors); if (ret < 0) { ferr("ERROR: rwb_invalidate failed: %d\n", ret); return ret; } /* Then let the lower level MTD driver do the real erase */ return priv->dev->erase(priv->dev, block, nblocks); } /************************************************************************************ * Name: mtd_bread ************************************************************************************/ static ssize_t mtd_bread(FAR struct mtd_dev_s *dev, off_t sector, size_t nsectors, FAR uint8_t *buffer) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_s *)dev; /* Let the rwbuffer logic do it real work. It will call out to mtd_reload if is * needs to read any data. */ return rwb_read(&priv->rwb, sector, nsectors, buffer); } /************************************************************************************ * Name: mtd_bwrite ************************************************************************************/ static ssize_t mtd_bwrite(FAR struct mtd_dev_s *dev, off_t block, size_t nsectors, FAR const uint8_t *buffer) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_s *)dev; /* Let the rwbuffer logic do it real work. It will call out to wrb_reload it is * needs to read any data. */ return rwb_write(&priv->rwb, block, nsectors, buffer); } /************************************************************************************ * Name: mtd_read ************************************************************************************/ static ssize_t mtd_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, FAR uint8_t *buffer) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_s *)dev; /* Let the rwbuffer logic do it real work. It will call out to mtd_reload it is * needs to read any data. */ return rwb_readbytes(&priv->rwb, offset, nbytes, buffer); } /************************************************************************************ * Name: mtd_ioctl ************************************************************************************/ static int mtd_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg) { FAR struct mtd_rwbuffer_s *priv = (FAR struct mtd_rwbuffer_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) { /* 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 = priv->rwb.blocksize; geo->erasesize = priv->rwb.blocksize * priv->spb; geo->neraseblocks = priv->rwb.nblocks / priv->spb; ret = OK; finfo("blocksize: %d erasesize: %d neraseblocks: %d\n", geo->blocksize, geo->erasesize, geo->neraseblocks); } } break; case MTDIOC_BULKERASE: { /* Erase the entire device */ ret = priv->dev->ioctl(priv->dev, MTDIOC_BULKERASE, 0); if (ret >= 0) { ferr("ERROR: Device ioctl failed: %d\n", ret); break; } /* Then invalidate in cached data */ ret = rwb_invalidate(&priv->rwb, 0, priv->rwb.nblocks); if (ret < 0) { ferr("ERROR: rwb_invalidate failed: %d\n", ret); } } break; case MTDIOC_XIPBASE: default: ret = -ENOTTY; /* Bad command */ break; } finfo("return %d\n", ret); return ret; } /************************************************************************************ * Public Functions ************************************************************************************/ /************************************************************************************ * Name: mtd_rwb_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 *mtd_rwb_initialize(FAR struct mtd_dev_s *mtd) { FAR struct mtd_rwbuffer_s *priv; struct mtd_geometry_s geo; int ret; finfo("mtd: %p\n", mtd); DEBUGASSERT(mtd && mtd->ioctl); /* Get the device geometry */ ret = mtd->ioctl(mtd, MTDIOC_GEOMETRY, (unsigned long)((uintptr_t)&geo)); if (ret < 0) { ferr("ERROR: MTDIOC_GEOMETRY ioctl failed: %d\n", ret); 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 = (FAR struct mtd_rwbuffer_s *)kmm_zalloc(sizeof(struct mtd_rwbuffer_s)); if (!priv) { ferr("ERROR: Failed to allocate mtd_rwbuffer\n"); return NULL; } /* Initialize the allocated structure. (unsupported methods/fields * were already nullified by kmm_zalloc). */ priv->mtd.erase = mtd_erase; /* Our MTD erase method */ priv->mtd.bread = mtd_bread; /* Our MTD bread method */ priv->mtd.bwrite = mtd_bwrite; /* Our MTD bwrite method */ priv->mtd.read = mtd_read; /* Our MTD read method */ priv->mtd.ioctl = mtd_ioctl; /* Our MTD ioctl method */ priv->dev = mtd; /* The contained MTD instance */ /* Sectors per block. The erase block size must be an even multiple * of the sector size. */ priv->spb = geo.erasesize / geo.blocksize; DEBUGASSERT((size_t)priv->spb * geo.blocksize == geo.erasesize); /* Values must be provided to rwb_initialize() */ /* Supported geometry */ priv->rwb.blocksize = geo.blocksize; priv->rwb.nblocks = geo.neraseblocks * priv->spb; /* Buffer setup */ #ifdef CONFIG_DRVR_WRITEBUFFER priv->rwb.wrmaxblocks = CONFIG_MTD_NWRBLOCKS; #endif #ifdef CONFIG_DRVR_READAHEAD priv->rwb.rhmaxblocks = CONFIG_MTD_NRDBLOCKS; #endif /* Callouts */ priv->rwb.dev = priv; /* Device state passed to callouts */ priv->rwb.wrflush = mtd_flush; /* Callout to flush buffer */ priv->rwb.rhreload = mtd_reload; /* Callout to reload buffer */ /* Initialize read-ahead/write buffering */ ret = rwb_initialize(&priv->rwb); if (ret < 0) { ferr("ERROR: rwb_initialize failed: %d\n", ret); kmm_free(priv); return NULL; } /* Register the MTD with the procfs system if enabled */ #ifdef CONFIG_MTD_REGISTRATION mtd_register(&priv->mtd, "rwbuffer"); #endif /* Return the implementation-specific state structure as the MTD device */ return &priv->mtd; } #endif /* CONFIG_DRVR_WRITEBUFFER || CONFIG_DRVR_READAHEAD */