/************************************************************************************ * drivers/mtd/at25.c * Driver for SPI-based AT25DF321 (32Mbit) flash. * * Copyright (C) 2009-2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * Petteri Aimonen * * 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 /************************************************************************************ * Pre-processor Definitions ************************************************************************************/ #ifndef CONFIG_AT25_SPIMODE # define CONFIG_AT25_SPIMODE SPIDEV_MODE0 #endif /* AT25 Registers *******************************************************************/ /* Indentification register values */ #define AT25_MANUFACTURER 0x1F #define AT25_AT25DF321_TYPE 0x47 /* 32 M-bit */ /* AT25DF321 capacity is 4,194,304 bytes: * (64 sectors) * (65,536 bytes per sector) * (16384 pages) * (256 bytes per page) */ #define AT25_AT25DF321_SECTOR_SHIFT 12 /* Sector size 1 << 12 = 4096 */ #define AT25_AT25DF321_NSECTORS 1024 #define AT25_AT25DF321_PAGE_SHIFT 9 /* Page size 1 << 9 = 512 */ #define AT25_AT25DF321_NPAGES 8192 /* Instructions */ /* Command Value N Description Addr Dummy Data */ #define AT25_WREN 0x06 /* 1 Write Enable 0 0 0 */ #define AT25_WRDI 0x04 /* 1 Write Disable 0 0 0 */ #define AT25_RDID 0x9f /* 1 Read Identification 0 0 1-3 */ #define AT25_RDSR 0x05 /* 1 Read Status Register 0 0 >=1 */ #define AT25_WRSR 0x01 /* 1 Write Status Register 0 0 1 */ #define AT25_READ 0x03 /* 1 Read Data Bytes 3 0 >=1 */ #define AT25_FAST_READ 0x0b /* 1 Higher speed read 3 1 >=1 */ #define AT25_PP 0x02 /* 1 Page Program 3 0 1-256 */ #define AT25_SE 0x20 /* 1 Sector Erase 3 0 0 */ #define AT25_BE 0xc7 /* 1 Bulk Erase 0 0 0 */ #define AT25_DP 0xb9 /* 2 Deep power down 0 0 0 */ #define AT25_RES 0xab /* 2 Read Electronic Signature 0 3 >=1 */ /* Status register bit definitions */ #define AT25_SR_WIP (1 << 0) /* Bit 0: Write in progress bit */ #define AT25_SR_WEL (1 << 1) /* Bit 1: Write enable latch bit */ #define AT25_SR_EPE (1 << 5) /* Bit 5: Erase/program error */ #define AT25_SR_UNPROT 0x00 /* Global unprotect command */ #define AT25_DUMMY 0xa5 /************************************************************************************ * 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 at25_dev_s. */ struct at25_dev_s { struct mtd_dev_s mtd; /* MTD interface */ FAR struct spi_dev_s *dev; /* Saved SPI interface instance */ uint8_t sectorshift; /* 16 or 18 */ uint8_t pageshift; /* 8 */ uint16_t nsectors; /* 128 or 64 */ uint32_t npages; /* 32,768 or 65,536 */ }; /************************************************************************************ * Private Function Prototypes ************************************************************************************/ /* Helpers */ static void at25_lock(FAR struct spi_dev_s *dev); static inline void at25_unlock(FAR struct spi_dev_s *dev); static inline int at25_readid(struct at25_dev_s *priv); static void at25_waitwritecomplete(struct at25_dev_s *priv); static void at25_writeenable(struct at25_dev_s *priv); static inline void at25_sectorerase(struct at25_dev_s *priv, off_t offset); static inline int at25_bulkerase(struct at25_dev_s *priv); static inline void at25_pagewrite(struct at25_dev_s *priv, FAR const uint8_t *buffer, off_t offset); /* MTD driver methods */ static int at25_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks); static ssize_t at25_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, FAR uint8_t *buf); static ssize_t at25_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, FAR const uint8_t *buf); static ssize_t at25_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, FAR uint8_t *buffer); static int at25_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg); /************************************************************************************ * Private Data ************************************************************************************/ /************************************************************************************ * Private Functions ************************************************************************************/ /************************************************************************************ * Name: at25_lock ************************************************************************************/ static void at25_lock(FAR struct spi_dev_s *dev) { /* On SPI busses where there are multiple devices, it will be necessary to * lock SPI to have exclusive access to the busses for a sequence of * transfers. The bus should be locked before the chip is selected. * * This is a blocking call and will not return until we have exclusiv access to * the SPI buss. We will retain that exclusive access until the bus is unlocked. */ (void)SPI_LOCK(dev, true); /* After locking the SPI bus, the we also need call the setfrequency, setbits, and * setmode methods to make sure that the SPI is properly configured for the device. * If the SPI buss is being shared, then it may have been left in an incompatible * state. */ SPI_SETMODE(dev, CONFIG_AT25_SPIMODE); SPI_SETBITS(dev, 8); (void)SPI_SETFREQUENCY(dev, 20000000); } /************************************************************************************ * Name: at25_unlock ************************************************************************************/ static inline void at25_unlock(FAR struct spi_dev_s *dev) { (void)SPI_LOCK(dev, false); } /************************************************************************************ * Name: at25_readid ************************************************************************************/ static inline int at25_readid(struct at25_dev_s *priv) { uint16_t manufacturer; uint16_t memory; uint16_t version; fvdbg("priv: %p\n", priv); /* Lock the SPI bus, configure the bus, and select this FLASH part. */ at25_lock(priv->dev); SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send the "Read ID (RDID)" command and read the first three ID bytes */ (void)SPI_SEND(priv->dev, AT25_RDID); manufacturer = SPI_SEND(priv->dev, AT25_DUMMY); memory = SPI_SEND(priv->dev, AT25_DUMMY); /* Deselect the FLASH and unlock the bus */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); at25_unlock(priv->dev); fvdbg("manufacturer: %02x memory: %02x\n", manufacturer, memory); /* Check for a valid manufacturer and memory type */ if (manufacturer == AT25_MANUFACTURER && memory == AT25_AT25DF321_TYPE) { priv->sectorshift = AT25_AT25DF321_SECTOR_SHIFT; priv->nsectors = AT25_AT25DF321_NSECTORS; priv->pageshift = AT25_AT25DF321_PAGE_SHIFT; priv->npages = AT25_AT25DF321_NPAGES; return OK; } return -ENODEV; } /************************************************************************************ * Name: at25_waitwritecomplete ************************************************************************************/ static void at25_waitwritecomplete(struct at25_dev_s *priv) { uint8_t status; /* Are we the only device on the bus? */ #ifdef CONFIG_SPI_OWNBUS /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send "Read Status Register (RDSR)" command */ (void)SPI_SEND(priv->dev, AT25_RDSR); /* Loop as long as the memory is busy with a write cycle */ do { /* Send a dummy byte to generate the clock needed to shift out the status */ status = SPI_SEND(priv->dev, AT25_DUMMY); } while ((status & AT25_SR_WIP) != 0); /* Deselect the FLASH */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); #else /* Loop as long as the memory is busy with a write cycle */ do { /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send "Read Status Register (RDSR)" command */ (void)SPI_SEND(priv->dev, AT25_RDSR); /* Send a dummy byte to generate the clock needed to shift out the status */ status = SPI_SEND(priv->dev, AT25_DUMMY); /* Deselect the FLASH */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); /* Given that writing could take up to few tens of milliseconds, and erasing * could take more. The following short delay in the "busy" case will allow * other peripherals to access the SPI bus. */ if ((status & AT25_SR_WIP) != 0) { at25_unlock(priv->dev); usleep(10000); at25_lock(priv->dev); } } while ((status & AT25_SR_WIP) != 0); #endif if (status & AT25_SR_EPE) { fdbg("Write error, status: 0x%02x\n", status); } fvdbg("Complete, status: 0x%02x\n", status); } /************************************************************************************ * Name: at25_writeenable ************************************************************************************/ static void at25_writeenable(struct at25_dev_s *priv) { SPI_SELECT(priv->dev, SPIDEV_FLASH, true); (void)SPI_SEND(priv->dev, AT25_WREN); SPI_SELECT(priv->dev, SPIDEV_FLASH, false); fvdbg("Enabled\n"); } /************************************************************************************ * Name: at25_sectorerase ************************************************************************************/ static inline void at25_sectorerase(struct at25_dev_s *priv, off_t sector) { off_t offset = sector << priv->sectorshift; fvdbg("sector: %08lx\n", (long)sector); /* Wait for any preceding write to complete. We could simplify things by * perform this wait at the end of each write operation (rather than at * the beginning of ALL operations), but have the wait first will slightly * improve performance. */ at25_waitwritecomplete(priv); /* Send write enable instruction */ at25_writeenable(priv); /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send the "Sector Erase (SE)" instruction */ (void)SPI_SEND(priv->dev, AT25_SE); /* Send the sector offset high byte first. For all of the supported * parts, the sector number is completely contained in the first byte * and the values used in the following two bytes don't really matter. */ (void)SPI_SEND(priv->dev, (offset >> 16) & 0xff); (void)SPI_SEND(priv->dev, (offset >> 8) & 0xff); (void)SPI_SEND(priv->dev, offset & 0xff); /* Deselect the FLASH */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); fvdbg("Erased\n"); } /************************************************************************************ * Name: at25_bulkerase ************************************************************************************/ static inline int at25_bulkerase(struct at25_dev_s *priv) { fvdbg("priv: %p\n", priv); /* Wait for any preceding write to complete. We could simplify things by * perform this wait at the end of each write operation (rather than at * the beginning of ALL operations), but have the wait first will slightly * improve performance. */ at25_waitwritecomplete(priv); /* Send write enable instruction */ at25_writeenable(priv); /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send the "Bulk Erase (BE)" instruction */ (void)SPI_SEND(priv->dev, AT25_BE); /* Deselect the FLASH */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); fvdbg("Return: OK\n"); return OK; } /************************************************************************************ * Name: at25_pagewrite ************************************************************************************/ static inline void at25_pagewrite(struct at25_dev_s *priv, FAR const uint8_t *buffer, off_t page) { off_t offset = page << 8; fvdbg("page: %08lx offset: %08lx\n", (long)page, (long)offset); /* Wait for any preceding write to complete. We could simplify things by * perform this wait at the end of each write operation (rather than at * the beginning of ALL operations), but have the wait first will slightly * improve performance. */ at25_waitwritecomplete(priv); /* Enable the write access to the FLASH */ at25_writeenable(priv); /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send "Page Program (PP)" command */ (void)SPI_SEND(priv->dev, AT25_PP); /* Send the page offset high byte first. */ (void)SPI_SEND(priv->dev, (offset >> 16) & 0xff); (void)SPI_SEND(priv->dev, (offset >> 8) & 0xff); (void)SPI_SEND(priv->dev, offset & 0xff); /* Then write the specified number of bytes */ SPI_SNDBLOCK(priv->dev, buffer, 256); /* Deselect the FLASH: Chip Select high */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); fvdbg("Written\n"); } /************************************************************************************ * Name: at25_erase ************************************************************************************/ static int at25_erase(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks) { FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev; size_t blocksleft = nblocks; fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); /* Lock access to the SPI bus until we complete the erase */ at25_lock(priv->dev); while (blocksleft-- > 0) { /* Erase each sector */ at25_sectorerase(priv, startblock); startblock++; } at25_unlock(priv->dev); return (int)nblocks; } /************************************************************************************ * Name: at25_bread ************************************************************************************/ static ssize_t at25_bread(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, FAR uint8_t *buffer) { FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev; ssize_t nbytes; fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); /* On this device, we can handle the block read just like the byte-oriented read */ nbytes = at25_read(dev, startblock << priv->pageshift, nblocks << priv->pageshift, buffer); if (nbytes > 0) { return nbytes >> priv->pageshift; } return (int)nbytes; } /************************************************************************************ * Name: at25_bwrite ************************************************************************************/ static ssize_t at25_bwrite(FAR struct mtd_dev_s *dev, off_t startblock, size_t nblocks, FAR const uint8_t *buffer) { FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev; size_t blocksleft = nblocks; fvdbg("startblock: %08lx nblocks: %d\n", (long)startblock, (int)nblocks); /* Lock the SPI bus and write each page to FLASH */ at25_lock(priv->dev); while (blocksleft-- > 0) { at25_pagewrite(priv, buffer, startblock * 2); at25_pagewrite(priv, buffer + 256, startblock * 2 + 1); buffer += 1 << priv->pageshift; startblock++; } at25_unlock(priv->dev); return nblocks; } /************************************************************************************ * Name: at25_read ************************************************************************************/ static ssize_t at25_read(FAR struct mtd_dev_s *dev, off_t offset, size_t nbytes, FAR uint8_t *buffer) { FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev; fvdbg("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes); /* Wait for any preceding write to complete. We could simplify things by * perform this wait at the end of each write operation (rather than at * the beginning of ALL operations), but have the wait first will slightly * improve performance. */ at25_waitwritecomplete(priv); /* Lock the SPI bus and select this FLASH part */ at25_lock(priv->dev); SPI_SELECT(priv->dev, SPIDEV_FLASH, true); /* Send "Read from Memory " instruction */ (void)SPI_SEND(priv->dev, AT25_READ); /* Send the page offset high byte first. */ (void)SPI_SEND(priv->dev, (offset >> 16) & 0xff); (void)SPI_SEND(priv->dev, (offset >> 8) & 0xff); (void)SPI_SEND(priv->dev, offset & 0xff); /* Then read all of the requested bytes */ SPI_RECVBLOCK(priv->dev, buffer, nbytes); /* Deselect the FLASH and unlock the SPI bus */ SPI_SELECT(priv->dev, SPIDEV_FLASH, false); at25_unlock(priv->dev); fvdbg("return nbytes: %d\n", (int)nbytes); return nbytes; } /************************************************************************************ * Name: at25_ioctl ************************************************************************************/ static int at25_ioctl(FAR struct mtd_dev_s *dev, int cmd, unsigned long arg) { FAR struct at25_dev_s *priv = (FAR struct at25_dev_s *)dev; int ret = -EINVAL; /* Assume good command with bad parameters */ fvdbg("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 = (1 << priv->pageshift); geo->erasesize = (1 << priv->sectorshift); geo->neraseblocks = priv->nsectors; ret = OK; fvdbg("blocksize: %d erasesize: %d neraseblocks: %d\n", geo->blocksize, geo->erasesize, geo->neraseblocks); } } break; case MTDIOC_BULKERASE: { /* Erase the entire device */ at25_lock(priv->dev); ret = at25_bulkerase(priv); at25_unlock(priv->dev); } break; case MTDIOC_XIPBASE: default: ret = -ENOTTY; /* Bad command */ break; } fvdbg("return %d\n", ret); return ret; } /************************************************************************************ * Public Functions ************************************************************************************/ /************************************************************************************ * Name: at25_initialize * * Description: * Create an initialize MTD device instance. 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 *at25_initialize(FAR struct spi_dev_s *dev) { FAR struct at25_dev_s *priv; int ret; fvdbg("dev: %p\n", dev); /* 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 definition) and so would have * to be extended to handle multiple FLASH parts on the same SPI bus. */ priv = (FAR struct at25_dev_s *)kzalloc(sizeof(struct at25_dev_s)); if (priv) { /* Initialize the allocated structure (unsupported methods were * nullified by kzalloc). */ priv->mtd.erase = at25_erase; priv->mtd.bread = at25_bread; priv->mtd.bwrite = at25_bwrite; priv->mtd.read = at25_read; priv->mtd.ioctl = at25_ioctl; priv->dev = dev; /* Deselect the FLASH */ SPI_SELECT(dev, SPIDEV_FLASH, false); /* Identify the FLASH chip and get its capacity */ ret = at25_readid(priv); if (ret != OK) { /* Unrecognized! Discard all of that work we just did and return NULL */ fdbg("Unrecognized\n"); kfree(priv); priv = NULL; } else { /* Unprotect all sectors */ at25_writeenable(priv); SPI_SELECT(priv->dev, SPIDEV_FLASH, true); (void)SPI_SEND(priv->dev, AT25_WRSR); (void)SPI_SEND(priv->dev, AT25_SR_UNPROT); SPI_SELECT(priv->dev, SPIDEV_FLASH, false); } } /* Return the implementation-specific state structure as the MTD device */ fvdbg("Return %p\n", priv); return (FAR struct mtd_dev_s *)priv; }