/**************************************************************************** * drivers/mtd/at25.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 #include #include #include #include #include #include #include #include #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Configuration ************************************************************/ #ifndef CONFIG_AT25_SPIMODE # define CONFIG_AT25_SPIMODE SPIDEV_MODE0 #endif #ifndef CONFIG_AT25_SPIFREQUENCY # define CONFIG_AT25_SPIFREQUENCY 20000000 #endif /* AT25 Registers ***********************************************************/ /* Identification register values */ #define AT25_MANUFACTURER 0x1f #define AT25_AT25DF081A_TYPE 0x45 /* 8 M-bit */ #define AT25_AT25DF321_TYPE 0x47 /* 32 M-bit */ /* AT25DF081A capacity is 1,048,575 bytes: * (16 sectors) * (65,536 bytes per sector) * (4096 pages) * (256 bytes per page) */ #define AT25_AT25DF081A_SECTOR_SHIFT 12 /* Sector size 1 << 12 = 4096 */ #define AT25_AT25DF081A_NSECTORS 256 #define AT25_AT25DF081A_PAGE_SHIFT 9 /* Page size 1 << 8 = 256 */ #define AT25_AT25DF081A_NPAGES 2048 /* 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_BUSY (1 << 0) /* Bit 0: Ready/Busy Status */ #define AT25_SR_WEL (1 << 1) /* Bit 1: Write enable latch bit */ #define AT25_SR_SWP_SHIFT (2) /* Bits 2-3: Software protection */ #define AT25_SR_SWP_MASK (3 << AT25_SR_SWP_SHIFT) #define AT25_SR_WPP (1 << 4) /* Bit 4: Write Protect (/WP) Pin Status */ #define AT25_SR_EPE (1 << 5) /* Bit 5: Erase/program error */ /* Bit 6: Reserved */ #define AT25_SR_SPRL (1 << 7) /* Bit 7: Sector Protection Registers Locked */ #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 Functions ****************************************************************************/ /**************************************************************************** * Name: at25_lock ****************************************************************************/ static void at25_lock(FAR struct spi_dev_s *dev) { /* On SPI buses where there are multiple devices, it will be necessary to * lock SPI to have exclusive access to the buses 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 exclusive * access to the SPI bus. * We will retain that exclusive access until the bus is unlocked. */ 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 bus is being shared, then it may have been left in an * incompatible state. */ SPI_SETMODE(dev, CONFIG_AT25_SPIMODE); SPI_SETBITS(dev, 8); SPI_HWFEATURES(dev, 0); SPI_SETFREQUENCY(dev, CONFIG_AT25_SPIFREQUENCY); } /**************************************************************************** * Name: at25_unlock ****************************************************************************/ static inline void at25_unlock(FAR struct spi_dev_s *dev) { SPI_LOCK(dev, false); } /**************************************************************************** * Name: at25_readid ****************************************************************************/ static inline int at25_readid(struct at25_dev_s *priv) { uint16_t manufacturer; uint16_t memory; finfo("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(0), true); /* Send the "Read ID (RDID)" command and read the first three ID bytes */ 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(0), false); at25_unlock(priv->dev); finfo("manufacturer: %02x memory: %02x\n", manufacturer, memory); /* Check for a valid manufacturer and memory type */ if (manufacturer == AT25_MANUFACTURER && memory == AT25_AT25DF081A_TYPE) { priv->sectorshift = AT25_AT25DF081A_SECTOR_SHIFT; priv->nsectors = AT25_AT25DF081A_NSECTORS; priv->pageshift = AT25_AT25DF081A_PAGE_SHIFT; priv->npages = AT25_AT25DF081A_NPAGES; return OK; } else 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; /* Loop as long as the memory is busy with a write cycle */ do { /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true); /* Send "Read Status Register (RDSR)" command */ 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(0), 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_BUSY) != 0) { at25_unlock(priv->dev); nxsig_usleep(10000); at25_lock(priv->dev); } } while ((status & AT25_SR_BUSY) != 0); if (status & AT25_SR_EPE) { ferr("ERROR: Write error, status: 0x%02x\n", status); } finfo("Complete, status: 0x%02x\n", status); } /**************************************************************************** * Name: at25_writeenable ****************************************************************************/ static void at25_writeenable(struct at25_dev_s *priv) { SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true); SPI_SEND(priv->dev, AT25_WREN); SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false); finfo("Enabled\n"); } /**************************************************************************** * Name: at25_sectorerase ****************************************************************************/ static inline void at25_sectorerase(struct at25_dev_s *priv, off_t sector) { off_t offset = sector << priv->sectorshift; finfo("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(0), true); /* Send the "Sector Erase (SE)" instruction */ 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. */ SPI_SEND(priv->dev, (offset >> 16) & 0xff); SPI_SEND(priv->dev, (offset >> 8) & 0xff); SPI_SEND(priv->dev, offset & 0xff); /* Deselect the FLASH */ SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false); finfo("Erased\n"); } /**************************************************************************** * Name: at25_bulkerase ****************************************************************************/ static inline int at25_bulkerase(struct at25_dev_s *priv) { finfo("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(0), true); /* Send the "Bulk Erase (BE)" instruction */ SPI_SEND(priv->dev, AT25_BE); /* Deselect the FLASH */ SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false); finfo("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; finfo("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(0), true); /* Send "Page Program (PP)" command */ SPI_SEND(priv->dev, AT25_PP); /* Send the page offset high byte first. */ SPI_SEND(priv->dev, (offset >> 16) & 0xff); SPI_SEND(priv->dev, (offset >> 8) & 0xff); 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(0), false); finfo("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; finfo("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; finfo("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; finfo("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; finfo("offset: %08lx nbytes: %d\n", (long)offset, (int)nbytes); /* Lock the SPI bus NOW because the following call must be executed with * the bus locked. */ at25_lock(priv->dev); /* 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); /* Select this FLASH part */ SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true); /* Send "Read from Memory " instruction */ SPI_SEND(priv->dev, AT25_READ); /* Send the page offset high byte first. */ SPI_SEND(priv->dev, (offset >> 16) & 0xff); SPI_SEND(priv->dev, (offset >> 8) & 0xff); 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(0), false); at25_unlock(priv->dev); finfo("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 */ 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 != NULL) { /* 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; finfo("blocksize: %" PRId32 " erasesize: %" PRId32 " neraseblocks: %" PRId32 "\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; } finfo("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; finfo("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(0) definition) and so would * have to be extended to handle multiple FLASH parts on the same SPI bus. */ priv = (FAR struct at25_dev_s *)kmm_zalloc(sizeof(struct at25_dev_s)); if (priv) { /* Initialize the allocated structure (unsupported methods were * nullified by kmm_zalloc). */ 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->mtd.name = "at25"; priv->dev = dev; /* Deselect the FLASH */ SPI_SELECT(dev, SPIDEV_FLASH(0), 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 */ ferr("ERROR: Unrecognized\n"); kmm_free(priv); return NULL; } else { /* Unprotect all sectors */ at25_writeenable(priv); SPI_SELECT(priv->dev, SPIDEV_FLASH(0), true); SPI_SEND(priv->dev, AT25_WRSR); SPI_SEND(priv->dev, AT25_SR_UNPROT); SPI_SELECT(priv->dev, SPIDEV_FLASH(0), false); } } /* Return the implementation-specific state structure as the MTD device */ finfo("Return %p\n", priv); return (FAR struct mtd_dev_s *)priv; }