/* * Copyright © 2004 Texas Instruments, Jian Zhang * Copyright © 2004 Micron Technology Inc. * Copyright © 2004 David Brownell * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DRIVER_NAME "omap2-nand" #define OMAP_NAND_TIMEOUT_MS 5000 #define NAND_Ecc_P1e (1 << 0) #define NAND_Ecc_P2e (1 << 1) #define NAND_Ecc_P4e (1 << 2) #define NAND_Ecc_P8e (1 << 3) #define NAND_Ecc_P16e (1 << 4) #define NAND_Ecc_P32e (1 << 5) #define NAND_Ecc_P64e (1 << 6) #define NAND_Ecc_P128e (1 << 7) #define NAND_Ecc_P256e (1 << 8) #define NAND_Ecc_P512e (1 << 9) #define NAND_Ecc_P1024e (1 << 10) #define NAND_Ecc_P2048e (1 << 11) #define NAND_Ecc_P1o (1 << 16) #define NAND_Ecc_P2o (1 << 17) #define NAND_Ecc_P4o (1 << 18) #define NAND_Ecc_P8o (1 << 19) #define NAND_Ecc_P16o (1 << 20) #define NAND_Ecc_P32o (1 << 21) #define NAND_Ecc_P64o (1 << 22) #define NAND_Ecc_P128o (1 << 23) #define NAND_Ecc_P256o (1 << 24) #define NAND_Ecc_P512o (1 << 25) #define NAND_Ecc_P1024o (1 << 26) #define NAND_Ecc_P2048o (1 << 27) #define TF(value) (value ? 1 : 0) #define P2048e(a) (TF(a & NAND_Ecc_P2048e) << 0) #define P2048o(a) (TF(a & NAND_Ecc_P2048o) << 1) #define P1e(a) (TF(a & NAND_Ecc_P1e) << 2) #define P1o(a) (TF(a & NAND_Ecc_P1o) << 3) #define P2e(a) (TF(a & NAND_Ecc_P2e) << 4) #define P2o(a) (TF(a & NAND_Ecc_P2o) << 5) #define P4e(a) (TF(a & NAND_Ecc_P4e) << 6) #define P4o(a) (TF(a & NAND_Ecc_P4o) << 7) #define P8e(a) (TF(a & NAND_Ecc_P8e) << 0) #define P8o(a) (TF(a & NAND_Ecc_P8o) << 1) #define P16e(a) (TF(a & NAND_Ecc_P16e) << 2) #define P16o(a) (TF(a & NAND_Ecc_P16o) << 3) #define P32e(a) (TF(a & NAND_Ecc_P32e) << 4) #define P32o(a) (TF(a & NAND_Ecc_P32o) << 5) #define P64e(a) (TF(a & NAND_Ecc_P64e) << 6) #define P64o(a) (TF(a & NAND_Ecc_P64o) << 7) #define P128e(a) (TF(a & NAND_Ecc_P128e) << 0) #define P128o(a) (TF(a & NAND_Ecc_P128o) << 1) #define P256e(a) (TF(a & NAND_Ecc_P256e) << 2) #define P256o(a) (TF(a & NAND_Ecc_P256o) << 3) #define P512e(a) (TF(a & NAND_Ecc_P512e) << 4) #define P512o(a) (TF(a & NAND_Ecc_P512o) << 5) #define P1024e(a) (TF(a & NAND_Ecc_P1024e) << 6) #define P1024o(a) (TF(a & NAND_Ecc_P1024o) << 7) #define P8e_s(a) (TF(a & NAND_Ecc_P8e) << 0) #define P8o_s(a) (TF(a & NAND_Ecc_P8o) << 1) #define P16e_s(a) (TF(a & NAND_Ecc_P16e) << 2) #define P16o_s(a) (TF(a & NAND_Ecc_P16o) << 3) #define P1e_s(a) (TF(a & NAND_Ecc_P1e) << 4) #define P1o_s(a) (TF(a & NAND_Ecc_P1o) << 5) #define P2e_s(a) (TF(a & NAND_Ecc_P2e) << 6) #define P2o_s(a) (TF(a & NAND_Ecc_P2o) << 7) #define P4e_s(a) (TF(a & NAND_Ecc_P4e) << 0) #define P4o_s(a) (TF(a & NAND_Ecc_P4o) << 1) #define PREFETCH_CONFIG1_CS_SHIFT 24 #define ECC_CONFIG_CS_SHIFT 1 #define CS_MASK 0x7 #define ENABLE_PREFETCH (0x1 << 7) #define DMA_MPU_MODE_SHIFT 2 #define ECCSIZE0_SHIFT 12 #define ECCSIZE1_SHIFT 22 #define ECC1RESULTSIZE 0x1 #define ECCCLEAR 0x100 #define ECC1 0x1 #define PREFETCH_FIFOTHRESHOLD_MAX 0x40 #define PREFETCH_FIFOTHRESHOLD(val) ((val) << 8) #define PREFETCH_STATUS_COUNT(val) (val & 0x00003fff) #define PREFETCH_STATUS_FIFO_CNT(val) ((val >> 24) & 0x7F) #define STATUS_BUFF_EMPTY 0x00000001 #define SECTOR_BYTES 512 /* 4 bit padding to make byte aligned, 56 = 52 + 4 */ #define BCH4_BIT_PAD 4 /* GPMC ecc engine settings for read */ #define BCH_WRAPMODE_1 1 /* BCH wrap mode 1 */ #define BCH8R_ECC_SIZE0 0x1a /* ecc_size0 = 26 */ #define BCH8R_ECC_SIZE1 0x2 /* ecc_size1 = 2 */ #define BCH4R_ECC_SIZE0 0xd /* ecc_size0 = 13 */ #define BCH4R_ECC_SIZE1 0x3 /* ecc_size1 = 3 */ /* GPMC ecc engine settings for write */ #define BCH_WRAPMODE_6 6 /* BCH wrap mode 6 */ #define BCH_ECC_SIZE0 0x0 /* ecc_size0 = 0, no oob protection */ #define BCH_ECC_SIZE1 0x20 /* ecc_size1 = 32 */ #define BADBLOCK_MARKER_LENGTH 2 static u_char bch16_vector[] = {0xf5, 0x24, 0x1c, 0xd0, 0x61, 0xb3, 0xf1, 0x55, 0x2e, 0x2c, 0x86, 0xa3, 0xed, 0x36, 0x1b, 0x78, 0x48, 0x76, 0xa9, 0x3b, 0x97, 0xd1, 0x7a, 0x93, 0x07, 0x0e}; static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc, 0xac, 0x6b, 0xff, 0x99, 0x7b}; static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10}; /* Shared among all NAND instances to synchronize access to the ECC Engine */ static struct nand_hw_control omap_gpmc_controller = { .lock = __SPIN_LOCK_UNLOCKED(omap_gpmc_controller.lock), .wq = __WAIT_QUEUE_HEAD_INITIALIZER(omap_gpmc_controller.wq), }; struct omap_nand_info { struct nand_chip nand; struct platform_device *pdev; int gpmc_cs; bool dev_ready; enum nand_io xfer_type; int devsize; enum omap_ecc ecc_opt; struct device_node *elm_of_node; unsigned long phys_base; struct completion comp; struct dma_chan *dma; int gpmc_irq_fifo; int gpmc_irq_count; enum { OMAP_NAND_IO_READ = 0, /* read */ OMAP_NAND_IO_WRITE, /* write */ } iomode; u_char *buf; int buf_len; /* Interface to GPMC */ struct gpmc_nand_regs reg; struct gpmc_nand_ops *ops; bool flash_bbt; /* fields specific for BCHx_HW ECC scheme */ struct device *elm_dev; /* NAND ready gpio */ struct gpio_desc *ready_gpiod; }; static inline struct omap_nand_info *mtd_to_omap(struct mtd_info *mtd) { return container_of(mtd_to_nand(mtd), struct omap_nand_info, nand); } /** * omap_prefetch_enable - configures and starts prefetch transfer * @cs: cs (chip select) number * @fifo_th: fifo threshold to be used for read/ write * @dma_mode: dma mode enable (1) or disable (0) * @u32_count: number of bytes to be transferred * @is_write: prefetch read(0) or write post(1) mode */ static int omap_prefetch_enable(int cs, int fifo_th, int dma_mode, unsigned int u32_count, int is_write, struct omap_nand_info *info) { u32 val; if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX) return -1; if (readl(info->reg.gpmc_prefetch_control)) return -EBUSY; /* Set the amount of bytes to be prefetched */ writel(u32_count, info->reg.gpmc_prefetch_config2); /* Set dma/mpu mode, the prefetch read / post write and * enable the engine. Set which cs is has requested for. */ val = ((cs << PREFETCH_CONFIG1_CS_SHIFT) | PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH | (dma_mode << DMA_MPU_MODE_SHIFT) | (is_write & 0x1)); writel(val, info->reg.gpmc_prefetch_config1); /* Start the prefetch engine */ writel(0x1, info->reg.gpmc_prefetch_control); return 0; } /** * omap_prefetch_reset - disables and stops the prefetch engine */ static int omap_prefetch_reset(int cs, struct omap_nand_info *info) { u32 config1; /* check if the same module/cs is trying to reset */ config1 = readl(info->reg.gpmc_prefetch_config1); if (((config1 >> PREFETCH_CONFIG1_CS_SHIFT) & CS_MASK) != cs) return -EINVAL; /* Stop the PFPW engine */ writel(0x0, info->reg.gpmc_prefetch_control); /* Reset/disable the PFPW engine */ writel(0x0, info->reg.gpmc_prefetch_config1); return 0; } /** * omap_hwcontrol - hardware specific access to control-lines * @mtd: MTD device structure * @cmd: command to device * @ctrl: * NAND_NCE: bit 0 -> don't care * NAND_CLE: bit 1 -> Command Latch * NAND_ALE: bit 2 -> Address Latch * * NOTE: boards may use different bits for these!! */ static void omap_hwcontrol(struct mtd_info *mtd, int cmd, unsigned int ctrl) { struct omap_nand_info *info = mtd_to_omap(mtd); if (cmd != NAND_CMD_NONE) { if (ctrl & NAND_CLE) writeb(cmd, info->reg.gpmc_nand_command); else if (ctrl & NAND_ALE) writeb(cmd, info->reg.gpmc_nand_address); else /* NAND_NCE */ writeb(cmd, info->reg.gpmc_nand_data); } } /** * omap_read_buf8 - read data from NAND controller into buffer * @mtd: MTD device structure * @buf: buffer to store date * @len: number of bytes to read */ static void omap_read_buf8(struct mtd_info *mtd, u_char *buf, int len) { struct nand_chip *nand = mtd_to_nand(mtd); ioread8_rep(nand->IO_ADDR_R, buf, len); } /** * omap_write_buf8 - write buffer to NAND controller * @mtd: MTD device structure * @buf: data buffer * @len: number of bytes to write */ static void omap_write_buf8(struct mtd_info *mtd, const u_char *buf, int len) { struct omap_nand_info *info = mtd_to_omap(mtd); u_char *p = (u_char *)buf; bool status; while (len--) { iowrite8(*p++, info->nand.IO_ADDR_W); /* wait until buffer is available for write */ do { status = info->ops->nand_writebuffer_empty(); } while (!status); } } /** * omap_read_buf16 - read data from NAND controller into buffer * @mtd: MTD device structure * @buf: buffer to store date * @len: number of bytes to read */ static void omap_read_buf16(struct mtd_info *mtd, u_char *buf, int len) { struct nand_chip *nand = mtd_to_nand(mtd); ioread16_rep(nand->IO_ADDR_R, buf, len / 2); } /** * omap_write_buf16 - write buffer to NAND controller * @mtd: MTD device structure * @buf: data buffer * @len: number of bytes to write */ static void omap_write_buf16(struct mtd_info *mtd, const u_char * buf, int len) { struct omap_nand_info *info = mtd_to_omap(mtd); u16 *p = (u16 *) buf; bool status; /* FIXME try bursts of writesw() or DMA ... */ len >>= 1; while (len--) { iowrite16(*p++, info->nand.IO_ADDR_W); /* wait until buffer is available for write */ do { status = info->ops->nand_writebuffer_empty(); } while (!status); } } /** * omap_read_buf_pref - read data from NAND controller into buffer * @mtd: MTD device structure * @buf: buffer to store date * @len: number of bytes to read */ static void omap_read_buf_pref(struct mtd_info *mtd, u_char *buf, int len) { struct omap_nand_info *info = mtd_to_omap(mtd); uint32_t r_count = 0; int ret = 0; u32 *p = (u32 *)buf; /* take care of subpage reads */ if (len % 4) { if (info->nand.options & NAND_BUSWIDTH_16) omap_read_buf16(mtd, buf, len % 4); else omap_read_buf8(mtd, buf, len % 4); p = (u32 *) (buf + len % 4); len -= len % 4; } /* configure and start prefetch transfer */ ret = omap_prefetch_enable(info->gpmc_cs, PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x0, info); if (ret) { /* PFPW engine is busy, use cpu copy method */ if (info->nand.options & NAND_BUSWIDTH_16) omap_read_buf16(mtd, (u_char *)p, len); else omap_read_buf8(mtd, (u_char *)p, len); } else { do { r_count = readl(info->reg.gpmc_prefetch_status); r_count = PREFETCH_STATUS_FIFO_CNT(r_count); r_count = r_count >> 2; ioread32_rep(info->nand.IO_ADDR_R, p, r_count); p += r_count; len -= r_count << 2; } while (len); /* disable and stop the PFPW engine */ omap_prefetch_reset(info->gpmc_cs, info); } } /** * omap_write_buf_pref - write buffer to NAND controller * @mtd: MTD device structure * @buf: data buffer * @len: number of bytes to write */ static void omap_write_buf_pref(struct mtd_info *mtd, const u_char *buf, int len) { struct omap_nand_info *info = mtd_to_omap(mtd); uint32_t w_count = 0; int i = 0, ret = 0; u16 *p = (u16 *)buf; unsigned long tim, limit; u32 val; /* take care of subpage writes */ if (len % 2 != 0) { writeb(*buf, info->nand.IO_ADDR_W); p = (u16 *)(buf + 1); len--; } /* configure and start prefetch transfer */ ret = omap_prefetch_enable(info->gpmc_cs, PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1, info); if (ret) { /* PFPW engine is busy, use cpu copy method */ if (info->nand.options & NAND_BUSWIDTH_16) omap_write_buf16(mtd, (u_char *)p, len); else omap_write_buf8(mtd, (u_char *)p, len); } else { while (len) { w_count = readl(info->reg.gpmc_prefetch_status); w_count = PREFETCH_STATUS_FIFO_CNT(w_count); w_count = w_count >> 1; for (i = 0; (i < w_count) && len; i++, len -= 2) iowrite16(*p++, info->nand.IO_ADDR_W); } /* wait for data to flushed-out before reset the prefetch */ tim = 0; limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS)); do { cpu_relax(); val = readl(info->reg.gpmc_prefetch_status); val = PREFETCH_STATUS_COUNT(val); } while (val && (tim++ < limit)); /* disable and stop the PFPW engine */ omap_prefetch_reset(info->gpmc_cs, info); } } /* * omap_nand_dma_callback: callback on the completion of dma transfer * @data: pointer to completion data structure */ static void omap_nand_dma_callback(void *data) { complete((struct completion *) data); } /* * omap_nand_dma_transfer: configure and start dma transfer * @mtd: MTD device structure * @addr: virtual address in RAM of source/destination * @len: number of data bytes to be transferred * @is_write: flag for read/write operation */ static inline int omap_nand_dma_transfer(struct mtd_info *mtd, void *addr, unsigned int len, int is_write) { struct omap_nand_info *info = mtd_to_omap(mtd); struct dma_async_tx_descriptor *tx; enum dma_data_direction dir = is_write ? DMA_TO_DEVICE : DMA_FROM_DEVICE; struct scatterlist sg; unsigned long tim, limit; unsigned n; int ret; u32 val; if (!virt_addr_valid(addr)) goto out_copy; sg_init_one(&sg, addr, len); n = dma_map_sg(info->dma->device->dev, &sg, 1, dir); if (n == 0) { dev_err(&info->pdev->dev, "Couldn't DMA map a %d byte buffer\n", len); goto out_copy; } tx = dmaengine_prep_slave_sg(info->dma, &sg, n, is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT | DMA_CTRL_ACK); if (!tx) goto out_copy_unmap; tx->callback = omap_nand_dma_callback; tx->callback_param = &info->comp; dmaengine_submit(tx); init_completion(&info->comp); /* setup and start DMA using dma_addr */ dma_async_issue_pending(info->dma); /* configure and start prefetch transfer */ ret = omap_prefetch_enable(info->gpmc_cs, PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write, info); if (ret) /* PFPW engine is busy, use cpu copy method */ goto out_copy_unmap; wait_for_completion(&info->comp); tim = 0; limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS)); do { cpu_relax(); val = readl(info->reg.gpmc_prefetch_status); val = PREFETCH_STATUS_COUNT(val); } while (val && (tim++ < limit)); /* disable and stop the PFPW engine */ omap_prefetch_reset(info->gpmc_cs, info); dma_unmap_sg(info->dma->device->dev, &sg, 1, dir); return 0; out_copy_unmap: dma_unmap_sg(info->dma->device->dev, &sg, 1, dir); out_copy: if (info->nand.options & NAND_BUSWIDTH_16) is_write == 0 ? omap_read_buf16(mtd, (u_char *) addr, len) : omap_write_buf16(mtd, (u_char *) addr, len); else is_write == 0 ? omap_read_buf8(mtd, (u_char *) addr, len) : omap_write_buf8(mtd, (u_char *) addr, len); return 0; } /** * omap_read_buf_dma_pref - read data from NAND controller into buffer * @mtd: MTD device structure * @buf: buffer to store date * @len: number of bytes to read */ static void omap_read_buf_dma_pref(struct mtd_info *mtd, u_char *buf, int len) { if (len <= mtd->oobsize) omap_read_buf_pref(mtd, buf, len); else /* start transfer in DMA mode */ omap_nand_dma_transfer(mtd, buf, len, 0x0); } /** * omap_write_buf_dma_pref - write buffer to NAND controller * @mtd: MTD device structure * @buf: data buffer * @len: number of bytes to write */ static void omap_write_buf_dma_pref(struct mtd_info *mtd, const u_char *buf, int len) { if (len <= mtd->oobsize) omap_write_buf_pref(mtd, buf, len); else /* start transfer in DMA mode */ omap_nand_dma_transfer(mtd, (u_char *) buf, len, 0x1); } /* * omap_nand_irq - GPMC irq handler * @this_irq: gpmc irq number * @dev: omap_nand_info structure pointer is passed here */ static irqreturn_t omap_nand_irq(int this_irq, void *dev) { struct omap_nand_info *info = (struct omap_nand_info *) dev; u32 bytes; bytes = readl(info->reg.gpmc_prefetch_status); bytes = PREFETCH_STATUS_FIFO_CNT(bytes); bytes = bytes & 0xFFFC; /* io in multiple of 4 bytes */ if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */ if (this_irq == info->gpmc_irq_count) goto done; if (info->buf_len && (info->buf_len < bytes)) bytes = info->buf_len; else if (!info->buf_len) bytes = 0; iowrite32_rep(info->nand.IO_ADDR_W, (u32 *)info->buf, bytes >> 2); info->buf = info->buf + bytes; info->buf_len -= bytes; } else { ioread32_rep(info->nand.IO_ADDR_R, (u32 *)info->buf, bytes >> 2); info->buf = info->buf + bytes; if (this_irq == info->gpmc_irq_count) goto done; } return IRQ_HANDLED; done: complete(&info->comp); disable_irq_nosync(info->gpmc_irq_fifo); disable_irq_nosync(info->gpmc_irq_count); return IRQ_HANDLED; } /* * omap_read_buf_irq_pref - read data from NAND controller into buffer * @mtd: MTD device structure * @buf: buffer to store date * @len: number of bytes to read */ static void omap_read_buf_irq_pref(struct mtd_info *mtd, u_char *buf, int len) { struct omap_nand_info *info = mtd_to_omap(mtd); int ret = 0; if (len <= mtd->oobsize) { omap_read_buf_pref(mtd, buf, len); return; } info->iomode = OMAP_NAND_IO_READ; info->buf = buf; init_completion(&info->comp); /* configure and start prefetch transfer */ ret = omap_prefetch_enable(info->gpmc_cs, PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0, info); if (ret) /* PFPW engine is busy, use cpu copy method */ goto out_copy; info->buf_len = len; enable_irq(info->gpmc_irq_count); enable_irq(info->gpmc_irq_fifo); /* waiting for read to complete */ wait_for_completion(&info->comp); /* disable and stop the PFPW engine */ omap_prefetch_reset(info->gpmc_cs, info); return; out_copy: if (info->nand.options & NAND_BUSWIDTH_16) omap_read_buf16(mtd, buf, len); else omap_read_buf8(mtd, buf, len); } /* * omap_write_buf_irq_pref - write buffer to NAND controller * @mtd: MTD device structure * @buf: data buffer * @len: number of bytes to write */ static void omap_write_buf_irq_pref(struct mtd_info *mtd, const u_char *buf, int len) { struct omap_nand_info *info = mtd_to_omap(mtd); int ret = 0; unsigned long tim, limit; u32 val; if (len <= mtd->oobsize) { omap_write_buf_pref(mtd, buf, len); return; } info->iomode = OMAP_NAND_IO_WRITE; info->buf = (u_char *) buf; init_completion(&info->comp); /* configure and start prefetch transfer : size=24 */ ret = omap_prefetch_enable(info->gpmc_cs, (PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1, info); if (ret) /* PFPW engine is busy, use cpu copy method */ goto out_copy; info->buf_len = len; enable_irq(info->gpmc_irq_count); enable_irq(info->gpmc_irq_fifo); /* waiting for write to complete */ wait_for_completion(&info->comp); /* wait for data to flushed-out before reset the prefetch */ tim = 0; limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS)); do { val = readl(info->reg.gpmc_prefetch_status); val = PREFETCH_STATUS_COUNT(val); cpu_relax(); } while (val && (tim++ < limit)); /* disable and stop the PFPW engine */ omap_prefetch_reset(info->gpmc_cs, info); return; out_copy: if (info->nand.options & NAND_BUSWIDTH_16) omap_write_buf16(mtd, buf, len); else omap_write_buf8(mtd, buf, len); } /** * gen_true_ecc - This function will generate true ECC value * @ecc_buf: buffer to store ecc code * * This generated true ECC value can be used when correcting * data read from NAND flash memory core */ static void gen_true_ecc(u8 *ecc_buf) { u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8); ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) | P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp)); ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) | P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp)); ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) | P1e(tmp) | P2048o(tmp) | P2048e(tmp)); } /** * omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data * @ecc_data1: ecc code from nand spare area * @ecc_data2: ecc code from hardware register obtained from hardware ecc * @page_data: page data * * This function compares two ECC's and indicates if there is an error. * If the error can be corrected it will be corrected to the buffer. * If there is no error, %0 is returned. If there is an error but it * was corrected, %1 is returned. Otherwise, %-1 is returned. */ static int omap_compare_ecc(u8 *ecc_data1, /* read from NAND memory */ u8 *ecc_data2, /* read from register */ u8 *page_data) { uint i; u8 tmp0_bit[8], tmp1_bit[8], tmp2_bit[8]; u8 comp0_bit[8], comp1_bit[8], comp2_bit[8]; u8 ecc_bit[24]; u8 ecc_sum = 0; u8 find_bit = 0; uint find_byte = 0; int isEccFF; isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF); gen_true_ecc(ecc_data1); gen_true_ecc(ecc_data2); for (i = 0; i <= 2; i++) { *(ecc_data1 + i) = ~(*(ecc_data1 + i)); *(ecc_data2 + i) = ~(*(ecc_data2 + i)); } for (i = 0; i < 8; i++) { tmp0_bit[i] = *ecc_data1 % 2; *ecc_data1 = *ecc_data1 / 2; } for (i = 0; i < 8; i++) { tmp1_bit[i] = *(ecc_data1 + 1) % 2; *(ecc_data1 + 1) = *(ecc_data1 + 1) / 2; } for (i = 0; i < 8; i++) { tmp2_bit[i] = *(ecc_data1 + 2) % 2; *(ecc_data1 + 2) = *(ecc_data1 + 2) / 2; } for (i = 0; i < 8; i++) { comp0_bit[i] = *ecc_data2 % 2; *ecc_data2 = *ecc_data2 / 2; } for (i = 0; i < 8; i++) { comp1_bit[i] = *(ecc_data2 + 1) % 2; *(ecc_data2 + 1) = *(ecc_data2 + 1) / 2; } for (i = 0; i < 8; i++) { comp2_bit[i] = *(ecc_data2 + 2) % 2; *(ecc_data2 + 2) = *(ecc_data2 + 2) / 2; } for (i = 0; i < 6; i++) ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2]; for (i = 0; i < 8; i++) ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i]; for (i = 0; i < 8; i++) ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i]; ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0]; ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1]; for (i = 0; i < 24; i++) ecc_sum += ecc_bit[i]; switch (ecc_sum) { case 0: /* Not reached because this function is not called if * ECC values are equal */ return 0; case 1: /* Uncorrectable error */ pr_debug("ECC UNCORRECTED_ERROR 1\n"); return -EBADMSG; case 11: /* UN-Correctable error */ pr_debug("ECC UNCORRECTED_ERROR B\n"); return -EBADMSG; case 12: /* Correctable error */ find_byte = (ecc_bit[23] << 8) + (ecc_bit[21] << 7) + (ecc_bit[19] << 6) + (ecc_bit[17] << 5) + (ecc_bit[15] << 4) + (ecc_bit[13] << 3) + (ecc_bit[11] << 2) + (ecc_bit[9] << 1) + ecc_bit[7]; find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1]; pr_debug("Correcting single bit ECC error at offset: " "%d, bit: %d\n", find_byte, find_bit); page_data[find_byte] ^= (1 << find_bit); return 1; default: if (isEccFF) { if (ecc_data2[0] == 0 && ecc_data2[1] == 0 && ecc_data2[2] == 0) return 0; } pr_debug("UNCORRECTED_ERROR default\n"); return -EBADMSG; } } /** * omap_correct_data - Compares the ECC read with HW generated ECC * @mtd: MTD device structure * @dat: page data * @read_ecc: ecc read from nand flash * @calc_ecc: ecc read from HW ECC registers * * Compares the ecc read from nand spare area with ECC registers values * and if ECC's mismatched, it will call 'omap_compare_ecc' for error * detection and correction. If there are no errors, %0 is returned. If * there were errors and all of the errors were corrected, the number of * corrected errors is returned. If uncorrectable errors exist, %-1 is * returned. */ static int omap_correct_data(struct mtd_info *mtd, u_char *dat, u_char *read_ecc, u_char *calc_ecc) { struct omap_nand_info *info = mtd_to_omap(mtd); int blockCnt = 0, i = 0, ret = 0; int stat = 0; /* Ex NAND_ECC_HW12_2048 */ if ((info->nand.ecc.mode == NAND_ECC_HW) && (info->nand.ecc.size == 2048)) blockCnt = 4; else blockCnt = 1; for (i = 0; i < blockCnt; i++) { if (memcmp(read_ecc, calc_ecc, 3) != 0) { ret = omap_compare_ecc(read_ecc, calc_ecc, dat); if (ret < 0) return ret; /* keep track of the number of corrected errors */ stat += ret; } read_ecc += 3; calc_ecc += 3; dat += 512; } return stat; } /** * omap_calcuate_ecc - Generate non-inverted ECC bytes. * @mtd: MTD device structure * @dat: The pointer to data on which ecc is computed * @ecc_code: The ecc_code buffer * * Using noninverted ECC can be considered ugly since writing a blank * page ie. padding will clear the ECC bytes. This is no problem as long * nobody is trying to write data on the seemingly unused page. Reading * an erased page will produce an ECC mismatch between generated and read * ECC bytes that has to be dealt with separately. */ static int omap_calculate_ecc(struct mtd_info *mtd, const u_char *dat, u_char *ecc_code) { struct omap_nand_info *info = mtd_to_omap(mtd); u32 val; val = readl(info->reg.gpmc_ecc_config); if (((val >> ECC_CONFIG_CS_SHIFT) & CS_MASK) != info->gpmc_cs) return -EINVAL; /* read ecc result */ val = readl(info->reg.gpmc_ecc1_result); *ecc_code++ = val; /* P128e, ..., P1e */ *ecc_code++ = val >> 16; /* P128o, ..., P1o */ /* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */ *ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0); return 0; } /** * omap_enable_hwecc - This function enables the hardware ecc functionality * @mtd: MTD device structure * @mode: Read/Write mode */ static void omap_enable_hwecc(struct mtd_info *mtd, int mode) { struct omap_nand_info *info = mtd_to_omap(mtd); struct nand_chip *chip = mtd_to_nand(mtd); unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0; u32 val; /* clear ecc and enable bits */ val = ECCCLEAR | ECC1; writel(val, info->reg.gpmc_ecc_control); /* program ecc and result sizes */ val = ((((info->nand.ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) | ECC1RESULTSIZE); writel(val, info->reg.gpmc_ecc_size_config); switch (mode) { case NAND_ECC_READ: case NAND_ECC_WRITE: writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control); break; case NAND_ECC_READSYN: writel(ECCCLEAR, info->reg.gpmc_ecc_control); break; default: dev_info(&info->pdev->dev, "error: unrecognized Mode[%d]!\n", mode); break; } /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */ val = (dev_width << 7) | (info->gpmc_cs << 1) | (0x1); writel(val, info->reg.gpmc_ecc_config); } /** * omap_wait - wait until the command is done * @mtd: MTD device structure * @chip: NAND Chip structure * * Wait function is called during Program and erase operations and * the way it is called from MTD layer, we should wait till the NAND * chip is ready after the programming/erase operation has completed. * * Erase can take up to 400ms and program up to 20ms according to * general NAND and SmartMedia specs */ static int omap_wait(struct mtd_info *mtd, struct nand_chip *chip) { struct nand_chip *this = mtd_to_nand(mtd); struct omap_nand_info *info = mtd_to_omap(mtd); unsigned long timeo = jiffies; int status, state = this->state; if (state == FL_ERASING) timeo += msecs_to_jiffies(400); else timeo += msecs_to_jiffies(20); writeb(NAND_CMD_STATUS & 0xFF, info->reg.gpmc_nand_command); while (time_before(jiffies, timeo)) { status = readb(info->reg.gpmc_nand_data); if (status & NAND_STATUS_READY) break; cond_resched(); } status = readb(info->reg.gpmc_nand_data); return status; } /** * omap_dev_ready - checks the NAND Ready GPIO line * @mtd: MTD device structure * * Returns true if ready and false if busy. */ static int omap_dev_ready(struct mtd_info *mtd) { struct omap_nand_info *info = mtd_to_omap(mtd); return gpiod_get_value(info->ready_gpiod); } /** * omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation * @mtd: MTD device structure * @mode: Read/Write mode * * When using BCH with SW correction (i.e. no ELM), sector size is set * to 512 bytes and we use BCH_WRAPMODE_6 wrapping mode * for both reading and writing with: * eccsize0 = 0 (no additional protected byte in spare area) * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area) */ static void __maybe_unused omap_enable_hwecc_bch(struct mtd_info *mtd, int mode) { unsigned int bch_type; unsigned int dev_width, nsectors; struct omap_nand_info *info = mtd_to_omap(mtd); enum omap_ecc ecc_opt = info->ecc_opt; struct nand_chip *chip = mtd_to_nand(mtd); u32 val, wr_mode; unsigned int ecc_size1, ecc_size0; /* GPMC configurations for calculating ECC */ switch (ecc_opt) { case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: bch_type = 0; nsectors = 1; wr_mode = BCH_WRAPMODE_6; ecc_size0 = BCH_ECC_SIZE0; ecc_size1 = BCH_ECC_SIZE1; break; case OMAP_ECC_BCH4_CODE_HW: bch_type = 0; nsectors = chip->ecc.steps; if (mode == NAND_ECC_READ) { wr_mode = BCH_WRAPMODE_1; ecc_size0 = BCH4R_ECC_SIZE0; ecc_size1 = BCH4R_ECC_SIZE1; } else { wr_mode = BCH_WRAPMODE_6; ecc_size0 = BCH_ECC_SIZE0; ecc_size1 = BCH_ECC_SIZE1; } break; case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: bch_type = 1; nsectors = 1; wr_mode = BCH_WRAPMODE_6; ecc_size0 = BCH_ECC_SIZE0; ecc_size1 = BCH_ECC_SIZE1; break; case OMAP_ECC_BCH8_CODE_HW: bch_type = 1; nsectors = chip->ecc.steps; if (mode == NAND_ECC_READ) { wr_mode = BCH_WRAPMODE_1; ecc_size0 = BCH8R_ECC_SIZE0; ecc_size1 = BCH8R_ECC_SIZE1; } else { wr_mode = BCH_WRAPMODE_6; ecc_size0 = BCH_ECC_SIZE0; ecc_size1 = BCH_ECC_SIZE1; } break; case OMAP_ECC_BCH16_CODE_HW: bch_type = 0x2; nsectors = chip->ecc.steps; if (mode == NAND_ECC_READ) { wr_mode = 0x01; ecc_size0 = 52; /* ECC bits in nibbles per sector */ ecc_size1 = 0; /* non-ECC bits in nibbles per sector */ } else { wr_mode = 0x01; ecc_size0 = 0; /* extra bits in nibbles per sector */ ecc_size1 = 52; /* OOB bits in nibbles per sector */ } break; default: return; } writel(ECC1, info->reg.gpmc_ecc_control); /* Configure ecc size for BCH */ val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT); writel(val, info->reg.gpmc_ecc_size_config); dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0; /* BCH configuration */ val = ((1 << 16) | /* enable BCH */ (bch_type << 12) | /* BCH4/BCH8/BCH16 */ (wr_mode << 8) | /* wrap mode */ (dev_width << 7) | /* bus width */ (((nsectors-1) & 0x7) << 4) | /* number of sectors */ (info->gpmc_cs << 1) | /* ECC CS */ (0x1)); /* enable ECC */ writel(val, info->reg.gpmc_ecc_config); /* Clear ecc and enable bits */ writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control); } static u8 bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f}; static u8 bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2, 0x97, 0x79, 0xe5, 0x24, 0xb5}; /** * omap_calculate_ecc_bch - Generate bytes of ECC bytes * @mtd: MTD device structure * @dat: The pointer to data on which ecc is computed * @ecc_code: The ecc_code buffer * * Support calculating of BCH4/8 ecc vectors for the page */ static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, const u_char *dat, u_char *ecc_calc) { struct omap_nand_info *info = mtd_to_omap(mtd); int eccbytes = info->nand.ecc.bytes; struct gpmc_nand_regs *gpmc_regs = &info->reg; u8 *ecc_code; unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4; u32 val; int i, j; nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1; for (i = 0; i < nsectors; i++) { ecc_code = ecc_calc; switch (info->ecc_opt) { case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: case OMAP_ECC_BCH8_CODE_HW: bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]); bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]); bch_val3 = readl(gpmc_regs->gpmc_bch_result2[i]); bch_val4 = readl(gpmc_regs->gpmc_bch_result3[i]); *ecc_code++ = (bch_val4 & 0xFF); *ecc_code++ = ((bch_val3 >> 24) & 0xFF); *ecc_code++ = ((bch_val3 >> 16) & 0xFF); *ecc_code++ = ((bch_val3 >> 8) & 0xFF); *ecc_code++ = (bch_val3 & 0xFF); *ecc_code++ = ((bch_val2 >> 24) & 0xFF); *ecc_code++ = ((bch_val2 >> 16) & 0xFF); *ecc_code++ = ((bch_val2 >> 8) & 0xFF); *ecc_code++ = (bch_val2 & 0xFF); *ecc_code++ = ((bch_val1 >> 24) & 0xFF); *ecc_code++ = ((bch_val1 >> 16) & 0xFF); *ecc_code++ = ((bch_val1 >> 8) & 0xFF); *ecc_code++ = (bch_val1 & 0xFF); break; case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: case OMAP_ECC_BCH4_CODE_HW: bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]); bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]); *ecc_code++ = ((bch_val2 >> 12) & 0xFF); *ecc_code++ = ((bch_val2 >> 4) & 0xFF); *ecc_code++ = ((bch_val2 & 0xF) << 4) | ((bch_val1 >> 28) & 0xF); *ecc_code++ = ((bch_val1 >> 20) & 0xFF); *ecc_code++ = ((bch_val1 >> 12) & 0xFF); *ecc_code++ = ((bch_val1 >> 4) & 0xFF); *ecc_code++ = ((bch_val1 & 0xF) << 4); break; case OMAP_ECC_BCH16_CODE_HW: val = readl(gpmc_regs->gpmc_bch_result6[i]); ecc_code[0] = ((val >> 8) & 0xFF); ecc_code[1] = ((val >> 0) & 0xFF); val = readl(gpmc_regs->gpmc_bch_result5[i]); ecc_code[2] = ((val >> 24) & 0xFF); ecc_code[3] = ((val >> 16) & 0xFF); ecc_code[4] = ((val >> 8) & 0xFF); ecc_code[5] = ((val >> 0) & 0xFF); val = readl(gpmc_regs->gpmc_bch_result4[i]); ecc_code[6] = ((val >> 24) & 0xFF); ecc_code[7] = ((val >> 16) & 0xFF); ecc_code[8] = ((val >> 8) & 0xFF); ecc_code[9] = ((val >> 0) & 0xFF); val = readl(gpmc_regs->gpmc_bch_result3[i]); ecc_code[10] = ((val >> 24) & 0xFF); ecc_code[11] = ((val >> 16) & 0xFF); ecc_code[12] = ((val >> 8) & 0xFF); ecc_code[13] = ((val >> 0) & 0xFF); val = readl(gpmc_regs->gpmc_bch_result2[i]); ecc_code[14] = ((val >> 24) & 0xFF); ecc_code[15] = ((val >> 16) & 0xFF); ecc_code[16] = ((val >> 8) & 0xFF); ecc_code[17] = ((val >> 0) & 0xFF); val = readl(gpmc_regs->gpmc_bch_result1[i]); ecc_code[18] = ((val >> 24) & 0xFF); ecc_code[19] = ((val >> 16) & 0xFF); ecc_code[20] = ((val >> 8) & 0xFF); ecc_code[21] = ((val >> 0) & 0xFF); val = readl(gpmc_regs->gpmc_bch_result0[i]); ecc_code[22] = ((val >> 24) & 0xFF); ecc_code[23] = ((val >> 16) & 0xFF); ecc_code[24] = ((val >> 8) & 0xFF); ecc_code[25] = ((val >> 0) & 0xFF); break; default: return -EINVAL; } /* ECC scheme specific syndrome customizations */ switch (info->ecc_opt) { case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: /* Add constant polynomial to remainder, so that * ECC of blank pages results in 0x0 on reading back */ for (j = 0; j < eccbytes; j++) ecc_calc[j] ^= bch4_polynomial[j]; break; case OMAP_ECC_BCH4_CODE_HW: /* Set 8th ECC byte as 0x0 for ROM compatibility */ ecc_calc[eccbytes - 1] = 0x0; break; case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: /* Add constant polynomial to remainder, so that * ECC of blank pages results in 0x0 on reading back */ for (j = 0; j < eccbytes; j++) ecc_calc[j] ^= bch8_polynomial[j]; break; case OMAP_ECC_BCH8_CODE_HW: /* Set 14th ECC byte as 0x0 for ROM compatibility */ ecc_calc[eccbytes - 1] = 0x0; break; case OMAP_ECC_BCH16_CODE_HW: break; default: return -EINVAL; } ecc_calc += eccbytes; } return 0; } /** * erased_sector_bitflips - count bit flips * @data: data sector buffer * @oob: oob buffer * @info: omap_nand_info * * Check the bit flips in erased page falls below correctable level. * If falls below, report the page as erased with correctable bit * flip, else report as uncorrectable page. */ static int erased_sector_bitflips(u_char *data, u_char *oob, struct omap_nand_info *info) { int flip_bits = 0, i; for (i = 0; i < info->nand.ecc.size; i++) { flip_bits += hweight8(~data[i]); if (flip_bits > info->nand.ecc.strength) return 0; } for (i = 0; i < info->nand.ecc.bytes - 1; i++) { flip_bits += hweight8(~oob[i]); if (flip_bits > info->nand.ecc.strength) return 0; } /* * Bit flips falls in correctable level. * Fill data area with 0xFF */ if (flip_bits) { memset(data, 0xFF, info->nand.ecc.size); memset(oob, 0xFF, info->nand.ecc.bytes); } return flip_bits; } /** * omap_elm_correct_data - corrects page data area in case error reported * @mtd: MTD device structure * @data: page data * @read_ecc: ecc read from nand flash * @calc_ecc: ecc read from HW ECC registers * * Calculated ecc vector reported as zero in case of non-error pages. * In case of non-zero ecc vector, first filter out erased-pages, and * then process data via ELM to detect bit-flips. */ static int omap_elm_correct_data(struct mtd_info *mtd, u_char *data, u_char *read_ecc, u_char *calc_ecc) { struct omap_nand_info *info = mtd_to_omap(mtd); struct nand_ecc_ctrl *ecc = &info->nand.ecc; int eccsteps = info->nand.ecc.steps; int i , j, stat = 0; int eccflag, actual_eccbytes; struct elm_errorvec err_vec[ERROR_VECTOR_MAX]; u_char *ecc_vec = calc_ecc; u_char *spare_ecc = read_ecc; u_char *erased_ecc_vec; u_char *buf; int bitflip_count; bool is_error_reported = false; u32 bit_pos, byte_pos, error_max, pos; int err; switch (info->ecc_opt) { case OMAP_ECC_BCH4_CODE_HW: /* omit 7th ECC byte reserved for ROM code compatibility */ actual_eccbytes = ecc->bytes - 1; erased_ecc_vec = bch4_vector; break; case OMAP_ECC_BCH8_CODE_HW: /* omit 14th ECC byte reserved for ROM code compatibility */ actual_eccbytes = ecc->bytes - 1; erased_ecc_vec = bch8_vector; break; case OMAP_ECC_BCH16_CODE_HW: actual_eccbytes = ecc->bytes; erased_ecc_vec = bch16_vector; break; default: dev_err(&info->pdev->dev, "invalid driver configuration\n"); return -EINVAL; } /* Initialize elm error vector to zero */ memset(err_vec, 0, sizeof(err_vec)); for (i = 0; i < eccsteps ; i++) { eccflag = 0; /* initialize eccflag */ /* * Check any error reported, * In case of error, non zero ecc reported. */ for (j = 0; j < actual_eccbytes; j++) { if (calc_ecc[j] != 0) { eccflag = 1; /* non zero ecc, error present */ break; } } if (eccflag == 1) { if (memcmp(calc_ecc, erased_ecc_vec, actual_eccbytes) == 0) { /* * calc_ecc[] matches pattern for ECC(all 0xff) * so this is definitely an erased-page */ } else { buf = &data[info->nand.ecc.size * i]; /* * count number of 0-bits in read_buf. * This check can be removed once a similar * check is introduced in generic NAND driver */ bitflip_count = erased_sector_bitflips( buf, read_ecc, info); if (bitflip_count) { /* * number of 0-bits within ECC limits * So this may be an erased-page */ stat += bitflip_count; } else { /* * Too many 0-bits. It may be a * - programmed-page, OR * - erased-page with many bit-flips * So this page requires check by ELM */ err_vec[i].error_reported = true; is_error_reported = true; } } } /* Update the ecc vector */ calc_ecc += ecc->bytes; read_ecc += ecc->bytes; } /* Check if any error reported */ if (!is_error_reported) return stat; /* Decode BCH error using ELM module */ elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec); err = 0; for (i = 0; i < eccsteps; i++) { if (err_vec[i].error_uncorrectable) { dev_err(&info->pdev->dev, "uncorrectable bit-flips found\n"); err = -EBADMSG; } else if (err_vec[i].error_reported) { for (j = 0; j < err_vec[i].error_count; j++) { switch (info->ecc_opt) { case OMAP_ECC_BCH4_CODE_HW: /* Add 4 bits to take care of padding */ pos = err_vec[i].error_loc[j] + BCH4_BIT_PAD; break; case OMAP_ECC_BCH8_CODE_HW: case OMAP_ECC_BCH16_CODE_HW: pos = err_vec[i].error_loc[j]; break; default: return -EINVAL; } error_max = (ecc->size + actual_eccbytes) * 8; /* Calculate bit position of error */ bit_pos = pos % 8; /* Calculate byte position of error */ byte_pos = (error_max - pos - 1) / 8; if (pos < error_max) { if (byte_pos < 512) { pr_debug("bitflip@dat[%d]=%x\n", byte_pos, data[byte_pos]); data[byte_pos] ^= 1 << bit_pos; } else { pr_debug("bitflip@oob[%d]=%x\n", (byte_pos - 512), spare_ecc[byte_pos - 512]); spare_ecc[byte_pos - 512] ^= 1 << bit_pos; } } else { dev_err(&info->pdev->dev, "invalid bit-flip @ %d:%d\n", byte_pos, bit_pos); err = -EBADMSG; } } } /* Update number of correctable errors */ stat += err_vec[i].error_count; /* Update page data with sector size */ data += ecc->size; spare_ecc += ecc->bytes; } return (err) ? err : stat; } /** * omap_write_page_bch - BCH ecc based write page function for entire page * @mtd: mtd info structure * @chip: nand chip info structure * @buf: data buffer * @oob_required: must write chip->oob_poi to OOB * @page: page * * Custom write page method evolved to support multi sector writing in one shot */ static int omap_write_page_bch(struct mtd_info *mtd, struct nand_chip *chip, const uint8_t *buf, int oob_required, int page) { int ret; uint8_t *ecc_calc = chip->buffers->ecccalc; /* Enable GPMC ecc engine */ chip->ecc.hwctl(mtd, NAND_ECC_WRITE); /* Write data */ chip->write_buf(mtd, buf, mtd->writesize); /* Update ecc vector from GPMC result registers */ chip->ecc.calculate(mtd, buf, &ecc_calc[0]); ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi, 0, chip->ecc.total); if (ret) return ret; /* Write ecc vector to OOB area */ chip->write_buf(mtd, chip->oob_poi, mtd->oobsize); return 0; } /** * omap_read_page_bch - BCH ecc based page read function for entire page * @mtd: mtd info structure * @chip: nand chip info structure * @buf: buffer to store read data * @oob_required: caller requires OOB data read to chip->oob_poi * @page: page number to read * * For BCH ecc scheme, GPMC used for syndrome calculation and ELM module * used for error correction. * Custom method evolved to support ELM error correction & multi sector * reading. On reading page data area is read along with OOB data with * ecc engine enabled. ecc vector updated after read of OOB data. * For non error pages ecc vector reported as zero. */ static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip, uint8_t *buf, int oob_required, int page) { uint8_t *ecc_calc = chip->buffers->ecccalc; uint8_t *ecc_code = chip->buffers->ecccode; int stat, ret; unsigned int max_bitflips = 0; /* Enable GPMC ecc engine */ chip->ecc.hwctl(mtd, NAND_ECC_READ); /* Read data */ chip->read_buf(mtd, buf, mtd->writesize); /* Read oob bytes */ chip->cmdfunc(mtd, NAND_CMD_RNDOUT, mtd->writesize + BADBLOCK_MARKER_LENGTH, -1); chip->read_buf(mtd, chip->oob_poi + BADBLOCK_MARKER_LENGTH, chip->ecc.total); /* Calculate ecc bytes */ chip->ecc.calculate(mtd, buf, ecc_calc); ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0, chip->ecc.total); if (ret) return ret; stat = chip->ecc.correct(mtd, buf, ecc_code, ecc_calc); if (stat < 0) { mtd->ecc_stats.failed++; } else { mtd->ecc_stats.corrected += stat; max_bitflips = max_t(unsigned int, max_bitflips, stat); } return max_bitflips; } /** * is_elm_present - checks for presence of ELM module by scanning DT nodes * @omap_nand_info: NAND device structure containing platform data */ static bool is_elm_present(struct omap_nand_info *info, struct device_node *elm_node) { struct platform_device *pdev; /* check whether elm-id is passed via DT */ if (!elm_node) { dev_err(&info->pdev->dev, "ELM devicetree node not found\n"); return false; } pdev = of_find_device_by_node(elm_node); /* check whether ELM device is registered */ if (!pdev) { dev_err(&info->pdev->dev, "ELM device not found\n"); return false; } /* ELM module available, now configure it */ info->elm_dev = &pdev->dev; return true; } static bool omap2_nand_ecc_check(struct omap_nand_info *info, struct omap_nand_platform_data *pdata) { bool ecc_needs_bch, ecc_needs_omap_bch, ecc_needs_elm; switch (info->ecc_opt) { case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: ecc_needs_omap_bch = false; ecc_needs_bch = true; ecc_needs_elm = false; break; case OMAP_ECC_BCH4_CODE_HW: case OMAP_ECC_BCH8_CODE_HW: case OMAP_ECC_BCH16_CODE_HW: ecc_needs_omap_bch = true; ecc_needs_bch = false; ecc_needs_elm = true; break; default: ecc_needs_omap_bch = false; ecc_needs_bch = false; ecc_needs_elm = false; break; } if (ecc_needs_bch && !IS_ENABLED(CONFIG_MTD_NAND_ECC_BCH)) { dev_err(&info->pdev->dev, "CONFIG_MTD_NAND_ECC_BCH not enabled\n"); return false; } if (ecc_needs_omap_bch && !IS_ENABLED(CONFIG_MTD_NAND_OMAP_BCH)) { dev_err(&info->pdev->dev, "CONFIG_MTD_NAND_OMAP_BCH not enabled\n"); return false; } if (ecc_needs_elm && !is_elm_present(info, info->elm_of_node)) { dev_err(&info->pdev->dev, "ELM not available\n"); return false; } return true; } static const char * const nand_xfer_types[] = { [NAND_OMAP_PREFETCH_POLLED] = "prefetch-polled", [NAND_OMAP_POLLED] = "polled", [NAND_OMAP_PREFETCH_DMA] = "prefetch-dma", [NAND_OMAP_PREFETCH_IRQ] = "prefetch-irq", }; static int omap_get_dt_info(struct device *dev, struct omap_nand_info *info) { struct device_node *child = dev->of_node; int i; const char *s; u32 cs; if (of_property_read_u32(child, "reg", &cs) < 0) { dev_err(dev, "reg not found in DT\n"); return -EINVAL; } info->gpmc_cs = cs; /* detect availability of ELM module. Won't be present pre-OMAP4 */ info->elm_of_node = of_parse_phandle(child, "ti,elm-id", 0); if (!info->elm_of_node) { info->elm_of_node = of_parse_phandle(child, "elm_id", 0); if (!info->elm_of_node) dev_dbg(dev, "ti,elm-id not in DT\n"); } /* select ecc-scheme for NAND */ if (of_property_read_string(child, "ti,nand-ecc-opt", &s)) { dev_err(dev, "ti,nand-ecc-opt not found\n"); return -EINVAL; } if (!strcmp(s, "sw")) { info->ecc_opt = OMAP_ECC_HAM1_CODE_SW; } else if (!strcmp(s, "ham1") || !strcmp(s, "hw") || !strcmp(s, "hw-romcode")) { info->ecc_opt = OMAP_ECC_HAM1_CODE_HW; } else if (!strcmp(s, "bch4")) { if (info->elm_of_node) info->ecc_opt = OMAP_ECC_BCH4_CODE_HW; else info->ecc_opt = OMAP_ECC_BCH4_CODE_HW_DETECTION_SW; } else if (!strcmp(s, "bch8")) { if (info->elm_of_node) info->ecc_opt = OMAP_ECC_BCH8_CODE_HW; else info->ecc_opt = OMAP_ECC_BCH8_CODE_HW_DETECTION_SW; } else if (!strcmp(s, "bch16")) { info->ecc_opt = OMAP_ECC_BCH16_CODE_HW; } else { dev_err(dev, "unrecognized value for ti,nand-ecc-opt\n"); return -EINVAL; } /* select data transfer mode */ if (!of_property_read_string(child, "ti,nand-xfer-type", &s)) { for (i = 0; i < ARRAY_SIZE(nand_xfer_types); i++) { if (!strcasecmp(s, nand_xfer_types[i])) { info->xfer_type = i; return 0; } } dev_err(dev, "unrecognized value for ti,nand-xfer-type\n"); return -EINVAL; } return 0; } static int omap_ooblayout_ecc(struct mtd_info *mtd, int section, struct mtd_oob_region *oobregion) { struct omap_nand_info *info = mtd_to_omap(mtd); struct nand_chip *chip = &info->nand; int off = BADBLOCK_MARKER_LENGTH; if (info->ecc_opt == OMAP_ECC_HAM1_CODE_HW && !(chip->options & NAND_BUSWIDTH_16)) off = 1; if (section) return -ERANGE; oobregion->offset = off; oobregion->length = chip->ecc.total; return 0; } static int omap_ooblayout_free(struct mtd_info *mtd, int section, struct mtd_oob_region *oobregion) { struct omap_nand_info *info = mtd_to_omap(mtd); struct nand_chip *chip = &info->nand; int off = BADBLOCK_MARKER_LENGTH; if (info->ecc_opt == OMAP_ECC_HAM1_CODE_HW && !(chip->options & NAND_BUSWIDTH_16)) off = 1; if (section) return -ERANGE; off += chip->ecc.total; if (off >= mtd->oobsize) return -ERANGE; oobregion->offset = off; oobregion->length = mtd->oobsize - off; return 0; } static const struct mtd_ooblayout_ops omap_ooblayout_ops = { .ecc = omap_ooblayout_ecc, .free = omap_ooblayout_free, }; static int omap_sw_ooblayout_ecc(struct mtd_info *mtd, int section, struct mtd_oob_region *oobregion) { struct nand_chip *chip = mtd_to_nand(mtd); int off = BADBLOCK_MARKER_LENGTH; if (section >= chip->ecc.steps) return -ERANGE; /* * When SW correction is employed, one OMAP specific marker byte is * reserved after each ECC step. */ oobregion->offset = off + (section * (chip->ecc.bytes + 1)); oobregion->length = chip->ecc.bytes; return 0; } static int omap_sw_ooblayout_free(struct mtd_info *mtd, int section, struct mtd_oob_region *oobregion) { struct nand_chip *chip = mtd_to_nand(mtd); int off = BADBLOCK_MARKER_LENGTH; if (section) return -ERANGE; /* * When SW correction is employed, one OMAP specific marker byte is * reserved after each ECC step. */ off += ((chip->ecc.bytes + 1) * chip->ecc.steps); if (off >= mtd->oobsize) return -ERANGE; oobregion->offset = off; oobregion->length = mtd->oobsize - off; return 0; } static const struct mtd_ooblayout_ops omap_sw_ooblayout_ops = { .ecc = omap_sw_ooblayout_ecc, .free = omap_sw_ooblayout_free, }; static int omap_nand_probe(struct platform_device *pdev) { struct omap_nand_info *info; struct omap_nand_platform_data *pdata = NULL; struct mtd_info *mtd; struct nand_chip *nand_chip; int err; dma_cap_mask_t mask; struct resource *res; struct device *dev = &pdev->dev; int min_oobbytes = BADBLOCK_MARKER_LENGTH; int oobbytes_per_step; info = devm_kzalloc(&pdev->dev, sizeof(struct omap_nand_info), GFP_KERNEL); if (!info) return -ENOMEM; info->pdev = pdev; if (dev->of_node) { if (omap_get_dt_info(dev, info)) return -EINVAL; } else { pdata = dev_get_platdata(&pdev->dev); if (!pdata) { dev_err(&pdev->dev, "platform data missing\n"); return -EINVAL; } info->gpmc_cs = pdata->cs; info->reg = pdata->reg; info->ecc_opt = pdata->ecc_opt; if (pdata->dev_ready) dev_info(&pdev->dev, "pdata->dev_ready is deprecated\n"); info->xfer_type = pdata->xfer_type; info->devsize = pdata->devsize; info->elm_of_node = pdata->elm_of_node; info->flash_bbt = pdata->flash_bbt; } platform_set_drvdata(pdev, info); info->ops = gpmc_omap_get_nand_ops(&info->reg, info->gpmc_cs); if (!info->ops) { dev_err(&pdev->dev, "Failed to get GPMC->NAND interface\n"); return -ENODEV; } nand_chip = &info->nand; mtd = nand_to_mtd(nand_chip); mtd->dev.parent = &pdev->dev; nand_chip->ecc.priv = NULL; nand_set_flash_node(nand_chip, dev->of_node); res = platform_get_resource(pdev, IORESOURCE_MEM, 0); nand_chip->IO_ADDR_R = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(nand_chip->IO_ADDR_R)) return PTR_ERR(nand_chip->IO_ADDR_R); info->phys_base = res->start; nand_chip->controller = &omap_gpmc_controller; nand_chip->IO_ADDR_W = nand_chip->IO_ADDR_R; nand_chip->cmd_ctrl = omap_hwcontrol; info->ready_gpiod = devm_gpiod_get_optional(&pdev->dev, "rb", GPIOD_IN); if (IS_ERR(info->ready_gpiod)) { dev_err(dev, "failed to get ready gpio\n"); return PTR_ERR(info->ready_gpiod); } /* * If RDY/BSY line is connected to OMAP then use the omap ready * function and the generic nand_wait function which reads the status * register after monitoring the RDY/BSY line. Otherwise use a standard * chip delay which is slightly more than tR (AC Timing) of the NAND * device and read status register until you get a failure or success */ if (info->ready_gpiod) { nand_chip->dev_ready = omap_dev_ready; nand_chip->chip_delay = 0; } else { nand_chip->waitfunc = omap_wait; nand_chip->chip_delay = 50; } if (info->flash_bbt) nand_chip->bbt_options |= NAND_BBT_USE_FLASH; /* scan NAND device connected to chip controller */ nand_chip->options |= info->devsize & NAND_BUSWIDTH_16; if (nand_scan_ident(mtd, 1, NULL)) { dev_err(&info->pdev->dev, "scan failed, may be bus-width mismatch\n"); err = -ENXIO; goto return_error; } if (nand_chip->bbt_options & NAND_BBT_USE_FLASH) nand_chip->bbt_options |= NAND_BBT_NO_OOB; else nand_chip->options |= NAND_SKIP_BBTSCAN; /* re-populate low-level callbacks based on xfer modes */ switch (info->xfer_type) { case NAND_OMAP_PREFETCH_POLLED: nand_chip->read_buf = omap_read_buf_pref; nand_chip->write_buf = omap_write_buf_pref; break; case NAND_OMAP_POLLED: /* Use nand_base defaults for {read,write}_buf */ break; case NAND_OMAP_PREFETCH_DMA: dma_cap_zero(mask); dma_cap_set(DMA_SLAVE, mask); info->dma = dma_request_chan(pdev->dev.parent, "rxtx"); if (IS_ERR(info->dma)) { dev_err(&pdev->dev, "DMA engine request failed\n"); err = PTR_ERR(info->dma); goto return_error; } else { struct dma_slave_config cfg; memset(&cfg, 0, sizeof(cfg)); cfg.src_addr = info->phys_base; cfg.dst_addr = info->phys_base; cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; cfg.src_maxburst = 16; cfg.dst_maxburst = 16; err = dmaengine_slave_config(info->dma, &cfg); if (err) { dev_err(&pdev->dev, "DMA engine slave config failed: %d\n", err); goto return_error; } nand_chip->read_buf = omap_read_buf_dma_pref; nand_chip->write_buf = omap_write_buf_dma_pref; } break; case NAND_OMAP_PREFETCH_IRQ: info->gpmc_irq_fifo = platform_get_irq(pdev, 0); if (info->gpmc_irq_fifo <= 0) { dev_err(&pdev->dev, "error getting fifo irq\n"); err = -ENODEV; goto return_error; } err = devm_request_irq(&pdev->dev, info->gpmc_irq_fifo, omap_nand_irq, IRQF_SHARED, "gpmc-nand-fifo", info); if (err) { dev_err(&pdev->dev, "requesting irq(%d) error:%d", info->gpmc_irq_fifo, err); info->gpmc_irq_fifo = 0; goto return_error; } info->gpmc_irq_count = platform_get_irq(pdev, 1); if (info->gpmc_irq_count <= 0) { dev_err(&pdev->dev, "error getting count irq\n"); err = -ENODEV; goto return_error; } err = devm_request_irq(&pdev->dev, info->gpmc_irq_count, omap_nand_irq, IRQF_SHARED, "gpmc-nand-count", info); if (err) { dev_err(&pdev->dev, "requesting irq(%d) error:%d", info->gpmc_irq_count, err); info->gpmc_irq_count = 0; goto return_error; } nand_chip->read_buf = omap_read_buf_irq_pref; nand_chip->write_buf = omap_write_buf_irq_pref; break; default: dev_err(&pdev->dev, "xfer_type(%d) not supported!\n", info->xfer_type); err = -EINVAL; goto return_error; } if (!omap2_nand_ecc_check(info, pdata)) { err = -EINVAL; goto return_error; } /* * Bail out earlier to let NAND_ECC_SOFT code create its own * ooblayout instead of using ours. */ if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW) { nand_chip->ecc.mode = NAND_ECC_SOFT; nand_chip->ecc.algo = NAND_ECC_HAMMING; goto scan_tail; } /* populate MTD interface based on ECC scheme */ switch (info->ecc_opt) { case OMAP_ECC_HAM1_CODE_HW: pr_info("nand: using OMAP_ECC_HAM1_CODE_HW\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.bytes = 3; nand_chip->ecc.size = 512; nand_chip->ecc.strength = 1; nand_chip->ecc.calculate = omap_calculate_ecc; nand_chip->ecc.hwctl = omap_enable_hwecc; nand_chip->ecc.correct = omap_correct_data; mtd_set_ooblayout(mtd, &omap_ooblayout_ops); oobbytes_per_step = nand_chip->ecc.bytes; if (!(nand_chip->options & NAND_BUSWIDTH_16)) min_oobbytes = 1; break; case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW: pr_info("nand: using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; nand_chip->ecc.bytes = 7; nand_chip->ecc.strength = 4; nand_chip->ecc.hwctl = omap_enable_hwecc_bch; nand_chip->ecc.correct = nand_bch_correct_data; nand_chip->ecc.calculate = omap_calculate_ecc_bch; mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops); /* Reserve one byte for the OMAP marker */ oobbytes_per_step = nand_chip->ecc.bytes + 1; /* software bch library is used for locating errors */ nand_chip->ecc.priv = nand_bch_init(mtd); if (!nand_chip->ecc.priv) { dev_err(&info->pdev->dev, "unable to use BCH library\n"); err = -EINVAL; goto return_error; } break; case OMAP_ECC_BCH4_CODE_HW: pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; /* 14th bit is kept reserved for ROM-code compatibility */ nand_chip->ecc.bytes = 7 + 1; nand_chip->ecc.strength = 4; nand_chip->ecc.hwctl = omap_enable_hwecc_bch; nand_chip->ecc.correct = omap_elm_correct_data; nand_chip->ecc.calculate = omap_calculate_ecc_bch; nand_chip->ecc.read_page = omap_read_page_bch; nand_chip->ecc.write_page = omap_write_page_bch; mtd_set_ooblayout(mtd, &omap_ooblayout_ops); oobbytes_per_step = nand_chip->ecc.bytes; err = elm_config(info->elm_dev, BCH4_ECC, mtd->writesize / nand_chip->ecc.size, nand_chip->ecc.size, nand_chip->ecc.bytes); if (err < 0) goto return_error; break; case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; nand_chip->ecc.bytes = 13; nand_chip->ecc.strength = 8; nand_chip->ecc.hwctl = omap_enable_hwecc_bch; nand_chip->ecc.correct = nand_bch_correct_data; nand_chip->ecc.calculate = omap_calculate_ecc_bch; mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops); /* Reserve one byte for the OMAP marker */ oobbytes_per_step = nand_chip->ecc.bytes + 1; /* software bch library is used for locating errors */ nand_chip->ecc.priv = nand_bch_init(mtd); if (!nand_chip->ecc.priv) { dev_err(&info->pdev->dev, "unable to use BCH library\n"); err = -EINVAL; goto return_error; } break; case OMAP_ECC_BCH8_CODE_HW: pr_info("nand: using OMAP_ECC_BCH8_CODE_HW ECC scheme\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; /* 14th bit is kept reserved for ROM-code compatibility */ nand_chip->ecc.bytes = 13 + 1; nand_chip->ecc.strength = 8; nand_chip->ecc.hwctl = omap_enable_hwecc_bch; nand_chip->ecc.correct = omap_elm_correct_data; nand_chip->ecc.calculate = omap_calculate_ecc_bch; nand_chip->ecc.read_page = omap_read_page_bch; nand_chip->ecc.write_page = omap_write_page_bch; mtd_set_ooblayout(mtd, &omap_ooblayout_ops); oobbytes_per_step = nand_chip->ecc.bytes; err = elm_config(info->elm_dev, BCH8_ECC, mtd->writesize / nand_chip->ecc.size, nand_chip->ecc.size, nand_chip->ecc.bytes); if (err < 0) goto return_error; break; case OMAP_ECC_BCH16_CODE_HW: pr_info("using OMAP_ECC_BCH16_CODE_HW ECC scheme\n"); nand_chip->ecc.mode = NAND_ECC_HW; nand_chip->ecc.size = 512; nand_chip->ecc.bytes = 26; nand_chip->ecc.strength = 16; nand_chip->ecc.hwctl = omap_enable_hwecc_bch; nand_chip->ecc.correct = omap_elm_correct_data; nand_chip->ecc.calculate = omap_calculate_ecc_bch; nand_chip->ecc.read_page = omap_read_page_bch; nand_chip->ecc.write_page = omap_write_page_bch; mtd_set_ooblayout(mtd, &omap_ooblayout_ops); oobbytes_per_step = nand_chip->ecc.bytes; err = elm_config(info->elm_dev, BCH16_ECC, mtd->writesize / nand_chip->ecc.size, nand_chip->ecc.size, nand_chip->ecc.bytes); if (err < 0) goto return_error; break; default: dev_err(&info->pdev->dev, "invalid or unsupported ECC scheme\n"); err = -EINVAL; goto return_error; } /* check if NAND device's OOB is enough to store ECC signatures */ min_oobbytes += (oobbytes_per_step * (mtd->writesize / nand_chip->ecc.size)); if (mtd->oobsize < min_oobbytes) { dev_err(&info->pdev->dev, "not enough OOB bytes required = %d, available=%d\n", min_oobbytes, mtd->oobsize); err = -EINVAL; goto return_error; } scan_tail: /* second phase scan */ if (nand_scan_tail(mtd)) { err = -ENXIO; goto return_error; } if (dev->of_node) mtd_device_register(mtd, NULL, 0); else mtd_device_register(mtd, pdata->parts, pdata->nr_parts); platform_set_drvdata(pdev, mtd); return 0; return_error: if (!IS_ERR_OR_NULL(info->dma)) dma_release_channel(info->dma); if (nand_chip->ecc.priv) { nand_bch_free(nand_chip->ecc.priv); nand_chip->ecc.priv = NULL; } return err; } static int omap_nand_remove(struct platform_device *pdev) { struct mtd_info *mtd = platform_get_drvdata(pdev); struct nand_chip *nand_chip = mtd_to_nand(mtd); struct omap_nand_info *info = mtd_to_omap(mtd); if (nand_chip->ecc.priv) { nand_bch_free(nand_chip->ecc.priv); nand_chip->ecc.priv = NULL; } if (info->dma) dma_release_channel(info->dma); nand_release(mtd); return 0; } static const struct of_device_id omap_nand_ids[] = { { .compatible = "ti,omap2-nand", }, {}, }; MODULE_DEVICE_TABLE(of, omap_nand_ids); static struct platform_driver omap_nand_driver = { .probe = omap_nand_probe, .remove = omap_nand_remove, .driver = { .name = DRIVER_NAME, .of_match_table = of_match_ptr(omap_nand_ids), }, }; module_platform_driver(omap_nand_driver); MODULE_ALIAS("platform:" DRIVER_NAME); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");