diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/mtd/nand/raw/omap2.c | 2307 |
1 files changed, 2307 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/omap2.c b/drivers/mtd/nand/raw/omap2.c new file mode 100644 index 000000000..4a9f2b6c7 --- /dev/null +++ b/drivers/mtd/nand/raw/omap2.c @@ -0,0 +1,2307 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com> + * Copyright © 2004 Micron Technology Inc. + * Copyright © 2004 David Brownell + */ + +#include <linux/platform_device.h> +#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> +#include <linux/delay.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/jiffies.h> +#include <linux/sched.h> +#include <linux/mtd/mtd.h> +#include <linux/mtd/nand-ecc-sw-bch.h> +#include <linux/mtd/rawnand.h> +#include <linux/mtd/partitions.h> +#include <linux/omap-dma.h> +#include <linux/iopoll.h> +#include <linux/slab.h> +#include <linux/of.h> +#include <linux/of_device.h> + +#include <linux/platform_data/elm.h> + +#include <linux/omap-gpmc.h> +#include <linux/platform_data/mtd-nand-omap2.h> + +#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 BBM_LEN 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}; + +struct omap_nand_info { + struct nand_chip nand; + struct platform_device *pdev; + + int gpmc_cs; + bool dev_ready; + enum nand_io xfer_type; + 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 */ + void __iomem *fifo; + 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; + unsigned int neccpg; + unsigned int nsteps_per_eccpg; + unsigned int eccpg_size; + unsigned int eccpg_bytes; + void (*data_in)(struct nand_chip *chip, void *buf, + unsigned int len, bool force_8bit); + void (*data_out)(struct nand_chip *chip, + const void *buf, unsigned int len, + bool force_8bit); +}; + +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); +} + +static void omap_nand_data_in(struct nand_chip *chip, void *buf, + unsigned int len, bool force_8bit); + +static void omap_nand_data_out(struct nand_chip *chip, + const void *buf, unsigned int len, + bool force_8bit); + +/** + * 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 + * @info: NAND device structure containing platform data + */ +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_nand_data_in_pref - NAND data in using prefetch engine + */ +static void omap_nand_data_in_pref(struct nand_chip *chip, void *buf, + unsigned int len, bool force_8bit) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + uint32_t r_count = 0; + int ret = 0; + u32 *p = (u32 *)buf; + unsigned int pref_len; + + if (force_8bit) { + omap_nand_data_in(chip, buf, len, force_8bit); + return; + } + + /* read 32-bit words using prefetch and remaining bytes normally */ + + /* configure and start prefetch transfer */ + pref_len = len - (len & 3); + ret = omap_prefetch_enable(info->gpmc_cs, + PREFETCH_FIFOTHRESHOLD_MAX, 0x0, pref_len, 0x0, info); + if (ret) { + /* prefetch engine is busy, use CPU copy method */ + omap_nand_data_in(chip, buf, len, false); + } 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->fifo, p, r_count); + p += r_count; + pref_len -= r_count << 2; + } while (pref_len); + /* disable and stop the Prefetch engine */ + omap_prefetch_reset(info->gpmc_cs, info); + /* fetch any remaining bytes */ + if (len & 3) + omap_nand_data_in(chip, p, len & 3, false); + } +} + +/** + * omap_nand_data_out_pref - NAND data out using Write Posting engine + */ +static void omap_nand_data_out_pref(struct nand_chip *chip, + const void *buf, unsigned int len, + bool force_8bit) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + uint32_t w_count = 0; + int i = 0, ret = 0; + u16 *p = (u16 *)buf; + unsigned long tim, limit; + u32 val; + + if (force_8bit) { + omap_nand_data_out(chip, buf, len, force_8bit); + return; + } + + /* take care of subpage writes */ + if (len % 2 != 0) { + writeb(*(u8 *)buf, info->fifo); + 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) { + /* write posting engine is busy, use CPU copy method */ + omap_nand_data_out(chip, buf, len, false); + } 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->fifo); + } + /* 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 + * @chip: nand chip 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 nand_chip *chip, + const void *addr, unsigned int len, + int is_write) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + 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: + is_write == 0 ? omap_nand_data_in(chip, (void *)addr, len, false) + : omap_nand_data_out(chip, addr, len, false); + + return 0; +} + +/** + * omap_nand_data_in_dma_pref - NAND data in using DMA and Prefetch + */ +static void omap_nand_data_in_dma_pref(struct nand_chip *chip, void *buf, + unsigned int len, bool force_8bit) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + + if (force_8bit) { + omap_nand_data_in(chip, buf, len, force_8bit); + return; + } + + if (len <= mtd->oobsize) + omap_nand_data_in_pref(chip, buf, len, false); + else + /* start transfer in DMA mode */ + omap_nand_dma_transfer(chip, buf, len, 0x0); +} + +/** + * omap_nand_data_out_dma_pref - NAND data out using DMA and write posting + */ +static void omap_nand_data_out_dma_pref(struct nand_chip *chip, + const void *buf, unsigned int len, + bool force_8bit) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + + if (force_8bit) { + omap_nand_data_out(chip, buf, len, force_8bit); + return; + } + + if (len <= mtd->oobsize) + omap_nand_data_out_pref(chip, buf, len, false); + else + /* start transfer in DMA mode */ + omap_nand_dma_transfer(chip, 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->fifo, (u32 *)info->buf, + bytes >> 2); + info->buf = info->buf + bytes; + info->buf_len -= bytes; + + } else { + ioread32_rep(info->fifo, (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_nand_data_in_irq_pref - NAND data in using Prefetch and IRQ + */ +static void omap_nand_data_in_irq_pref(struct nand_chip *chip, void *buf, + unsigned int len, bool force_8bit) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + struct mtd_info *mtd = nand_to_mtd(&info->nand); + int ret = 0; + + if (len <= mtd->oobsize || force_8bit) { + omap_nand_data_in(chip, buf, len, force_8bit); + 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 */ + omap_nand_data_in(chip, buf, len, false); + return; + } + + 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; +} + +/* + * omap_nand_data_out_irq_pref - NAND out using write posting and IRQ + */ +static void omap_nand_data_out_irq_pref(struct nand_chip *chip, + const void *buf, unsigned int len, + bool force_8bit) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + struct mtd_info *mtd = nand_to_mtd(&info->nand); + int ret = 0; + unsigned long tim, limit; + u32 val; + + if (len <= mtd->oobsize || force_8bit) { + omap_nand_data_out(chip, buf, len, force_8bit); + 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 */ + omap_nand_data_out(chip, buf, len, false); + return; + } + + 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; +} + +/** + * 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 + * @chip: NAND chip object + * @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 nand_chip *chip, u_char *dat, + u_char *read_ecc, u_char *calc_ecc) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + int blockCnt = 0, i = 0, ret = 0; + int stat = 0; + + /* Ex NAND_ECC_HW12_2048 */ + if (info->nand.ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST && + 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_calculate_ecc - Generate non-inverted ECC bytes. + * @chip: NAND chip object + * @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 nand_chip *chip, const u_char *dat, + u_char *ecc_code) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + 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 + * @chip: NAND chip object + * @mode: Read/Write mode + */ +static void omap_enable_hwecc(struct nand_chip *chip, int mode) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + 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_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation + * @chip: NAND chip object + * @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 nand_chip *chip, + int mode) +{ + unsigned int bch_type; + unsigned int dev_width, nsectors; + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + enum omap_ecc ecc_opt = info->ecc_opt; + 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 ECC bytes for one sector + * @mtd: MTD device structure + * @dat: The pointer to data on which ecc is computed + * @ecc_calc: The ecc_code buffer + * @i: The sector number (for a multi sector page) + * + * Support calculating of BCH4/8/16 ECC vectors for one sector + * within a page. Sector number is in @i. + */ +static int _omap_calculate_ecc_bch(struct mtd_info *mtd, + const u_char *dat, u_char *ecc_calc, int i) +{ + 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 bch_val1, bch_val2, bch_val3, bch_val4; + u32 val; + int j; + + 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; + } + + return 0; +} + +/** + * omap_calculate_ecc_bch_sw - ECC generator for sector for SW based correction + * @chip: NAND chip object + * @dat: The pointer to data on which ecc is computed + * @ecc_calc: Buffer storing the calculated ECC bytes + * + * Support calculating of BCH4/8/16 ECC vectors for one sector. This is used + * when SW based correction is required as ECC is required for one sector + * at a time. + */ +static int omap_calculate_ecc_bch_sw(struct nand_chip *chip, + const u_char *dat, u_char *ecc_calc) +{ + return _omap_calculate_ecc_bch(nand_to_mtd(chip), dat, ecc_calc, 0); +} + +/** + * omap_calculate_ecc_bch_multi - Generate ECC for multiple sectors + * @mtd: MTD device structure + * @dat: The pointer to data on which ecc is computed + * @ecc_calc: Buffer storing the calculated ECC bytes + * + * Support calculating of BCH4/8/16 ecc vectors for the entire page in one go. + */ +static int omap_calculate_ecc_bch_multi(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; + unsigned long nsectors; + int i, ret; + + nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1; + for (i = 0; i < nsectors; i++) { + ret = _omap_calculate_ecc_bch(mtd, dat, ecc_calc, i); + if (ret) + return ret; + + 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 + * @chip: NAND chip object + * @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 nand_chip *chip, u_char *data, + u_char *read_ecc, u_char *calc_ecc) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + struct nand_ecc_ctrl *ecc = &info->nand.ecc; + int eccsteps = info->nsteps_per_eccpg; + 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 = max_t(unsigned int, 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 + * @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 nand_chip *chip, const uint8_t *buf, + int oob_required, int page) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + struct omap_nand_info *info = mtd_to_omap(mtd); + uint8_t *ecc_calc = chip->ecc.calc_buf; + unsigned int eccpg; + int ret; + + ret = nand_prog_page_begin_op(chip, page, 0, NULL, 0); + if (ret) + return ret; + + for (eccpg = 0; eccpg < info->neccpg; eccpg++) { + /* Enable GPMC ecc engine */ + chip->ecc.hwctl(chip, NAND_ECC_WRITE); + + /* Write data */ + info->data_out(chip, buf + (eccpg * info->eccpg_size), + info->eccpg_size, false); + + /* Update ecc vector from GPMC result registers */ + ret = omap_calculate_ecc_bch_multi(mtd, + buf + (eccpg * info->eccpg_size), + ecc_calc); + if (ret) + return ret; + + ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, + chip->oob_poi, + eccpg * info->eccpg_bytes, + info->eccpg_bytes); + if (ret) + return ret; + } + + /* Write ecc vector to OOB area */ + info->data_out(chip, chip->oob_poi, mtd->oobsize, false); + + return nand_prog_page_end_op(chip); +} + +/** + * omap_write_subpage_bch - BCH hardware ECC based subpage write + * @chip: nand chip info structure + * @offset: column address of subpage within the page + * @data_len: data length + * @buf: data buffer + * @oob_required: must write chip->oob_poi to OOB + * @page: page number to write + * + * OMAP optimized subpage write method. + */ +static int omap_write_subpage_bch(struct nand_chip *chip, u32 offset, + u32 data_len, const u8 *buf, + int oob_required, int page) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + struct omap_nand_info *info = mtd_to_omap(mtd); + u8 *ecc_calc = chip->ecc.calc_buf; + int ecc_size = chip->ecc.size; + int ecc_bytes = chip->ecc.bytes; + u32 start_step = offset / ecc_size; + u32 end_step = (offset + data_len - 1) / ecc_size; + unsigned int eccpg; + int step, ret = 0; + + /* + * Write entire page at one go as it would be optimal + * as ECC is calculated by hardware. + * ECC is calculated for all subpages but we choose + * only what we want. + */ + ret = nand_prog_page_begin_op(chip, page, 0, NULL, 0); + if (ret) + return ret; + + for (eccpg = 0; eccpg < info->neccpg; eccpg++) { + /* Enable GPMC ECC engine */ + chip->ecc.hwctl(chip, NAND_ECC_WRITE); + + /* Write data */ + info->data_out(chip, buf + (eccpg * info->eccpg_size), + info->eccpg_size, false); + + for (step = 0; step < info->nsteps_per_eccpg; step++) { + unsigned int base_step = eccpg * info->nsteps_per_eccpg; + const u8 *bufoffs = buf + (eccpg * info->eccpg_size); + + /* Mask ECC of un-touched subpages with 0xFFs */ + if ((step + base_step) < start_step || + (step + base_step) > end_step) + memset(ecc_calc + (step * ecc_bytes), 0xff, + ecc_bytes); + else + ret = _omap_calculate_ecc_bch(mtd, + bufoffs + (step * ecc_size), + ecc_calc + (step * ecc_bytes), + step); + + if (ret) + return ret; + } + + /* + * Copy the calculated ECC for the whole page including the + * masked values (0xFF) corresponding to unwritten subpages. + */ + ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi, + eccpg * info->eccpg_bytes, + info->eccpg_bytes); + if (ret) + return ret; + } + + /* write OOB buffer to NAND device */ + info->data_out(chip, chip->oob_poi, mtd->oobsize, false); + + return nand_prog_page_end_op(chip); +} + +/** + * omap_read_page_bch - BCH ecc based page read function for entire page + * @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 nand_chip *chip, uint8_t *buf, + int oob_required, int page) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + struct omap_nand_info *info = mtd_to_omap(mtd); + uint8_t *ecc_calc = chip->ecc.calc_buf; + uint8_t *ecc_code = chip->ecc.code_buf; + unsigned int max_bitflips = 0, eccpg; + int stat, ret; + + ret = nand_read_page_op(chip, page, 0, NULL, 0); + if (ret) + return ret; + + for (eccpg = 0; eccpg < info->neccpg; eccpg++) { + /* Enable GPMC ecc engine */ + chip->ecc.hwctl(chip, NAND_ECC_READ); + + /* Read data */ + ret = nand_change_read_column_op(chip, eccpg * info->eccpg_size, + buf + (eccpg * info->eccpg_size), + info->eccpg_size, false); + if (ret) + return ret; + + /* Read oob bytes */ + ret = nand_change_read_column_op(chip, + mtd->writesize + BBM_LEN + + (eccpg * info->eccpg_bytes), + chip->oob_poi + BBM_LEN + + (eccpg * info->eccpg_bytes), + info->eccpg_bytes, false); + if (ret) + return ret; + + /* Calculate ecc bytes */ + ret = omap_calculate_ecc_bch_multi(mtd, + buf + (eccpg * info->eccpg_size), + ecc_calc); + if (ret) + return ret; + + ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, + chip->oob_poi, + eccpg * info->eccpg_bytes, + info->eccpg_bytes); + if (ret) + return ret; + + stat = chip->ecc.correct(chip, + buf + (eccpg * info->eccpg_size), + 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 + * @info: NAND device structure containing platform data + * @elm_node: ELM's DT node + */ +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) +{ + 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_SW_BCH)) { + dev_err(&info->pdev->dev, + "CONFIG_MTD_NAND_ECC_SW_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 = BBM_LEN; + + 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 = BBM_LEN; + + 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_device *nand = mtd_to_nanddev(mtd); + unsigned int nsteps = nanddev_get_ecc_nsteps(nand); + unsigned int ecc_bytes = nanddev_get_ecc_bytes_per_step(nand); + int off = BBM_LEN; + + if (section >= nsteps) + return -ERANGE; + + /* + * When SW correction is employed, one OMAP specific marker byte is + * reserved after each ECC step. + */ + oobregion->offset = off + (section * (ecc_bytes + 1)); + oobregion->length = ecc_bytes; + + return 0; +} + +static int omap_sw_ooblayout_free(struct mtd_info *mtd, int section, + struct mtd_oob_region *oobregion) +{ + struct nand_device *nand = mtd_to_nanddev(mtd); + unsigned int nsteps = nanddev_get_ecc_nsteps(nand); + unsigned int ecc_bytes = nanddev_get_ecc_bytes_per_step(nand); + int off = BBM_LEN; + + if (section) + return -ERANGE; + + /* + * When SW correction is employed, one OMAP specific marker byte is + * reserved after each ECC step. + */ + off += ((ecc_bytes + 1) * nsteps); + 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_attach_chip(struct nand_chip *chip) +{ + struct mtd_info *mtd = nand_to_mtd(chip); + struct omap_nand_info *info = mtd_to_omap(mtd); + struct device *dev = &info->pdev->dev; + int min_oobbytes = BBM_LEN; + int elm_bch_strength = -1; + int oobbytes_per_step; + dma_cap_mask_t mask; + int err; + + if (chip->bbt_options & NAND_BBT_USE_FLASH) + chip->bbt_options |= NAND_BBT_NO_OOB; + else + chip->options |= NAND_SKIP_BBTSCAN; + + /* Re-populate low-level callbacks based on xfer modes */ + switch (info->xfer_type) { + case NAND_OMAP_PREFETCH_POLLED: + info->data_in = omap_nand_data_in_pref; + info->data_out = omap_nand_data_out_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(dev->parent, "rxtx"); + + if (IS_ERR(info->dma)) { + dev_err(dev, "DMA engine request failed\n"); + return PTR_ERR(info->dma); + } 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(dev, + "DMA engine slave config failed: %d\n", + err); + return err; + } + + info->data_in = omap_nand_data_in_dma_pref; + info->data_out = omap_nand_data_out_dma_pref; + } + break; + + case NAND_OMAP_PREFETCH_IRQ: + info->gpmc_irq_fifo = platform_get_irq(info->pdev, 0); + if (info->gpmc_irq_fifo <= 0) + return -ENODEV; + err = devm_request_irq(dev, info->gpmc_irq_fifo, + omap_nand_irq, IRQF_SHARED, + "gpmc-nand-fifo", info); + if (err) { + dev_err(dev, "Requesting IRQ %d, error %d\n", + info->gpmc_irq_fifo, err); + info->gpmc_irq_fifo = 0; + return err; + } + + info->gpmc_irq_count = platform_get_irq(info->pdev, 1); + if (info->gpmc_irq_count <= 0) + return -ENODEV; + err = devm_request_irq(dev, info->gpmc_irq_count, + omap_nand_irq, IRQF_SHARED, + "gpmc-nand-count", info); + if (err) { + dev_err(dev, "Requesting IRQ %d, error %d\n", + info->gpmc_irq_count, err); + info->gpmc_irq_count = 0; + return err; + } + + info->data_in = omap_nand_data_in_irq_pref; + info->data_out = omap_nand_data_out_irq_pref; + break; + + default: + dev_err(dev, "xfer_type %d not supported!\n", info->xfer_type); + return -EINVAL; + } + + if (!omap2_nand_ecc_check(info)) + return -EINVAL; + + /* + * Bail out earlier to let NAND_ECC_ENGINE_TYPE_SOFT code create its own + * ooblayout instead of using ours. + */ + if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW) { + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT; + chip->ecc.algo = NAND_ECC_ALGO_HAMMING; + return 0; + } + + /* Populate MTD interface based on ECC scheme */ + switch (info->ecc_opt) { + case OMAP_ECC_HAM1_CODE_HW: + dev_info(dev, "nand: using OMAP_ECC_HAM1_CODE_HW\n"); + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.bytes = 3; + chip->ecc.size = 512; + chip->ecc.strength = 1; + chip->ecc.calculate = omap_calculate_ecc; + chip->ecc.hwctl = omap_enable_hwecc; + chip->ecc.correct = omap_correct_data; + mtd_set_ooblayout(mtd, &omap_ooblayout_ops); + oobbytes_per_step = chip->ecc.bytes; + + if (!(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"); + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.size = 512; + chip->ecc.bytes = 7; + chip->ecc.strength = 4; + chip->ecc.hwctl = omap_enable_hwecc_bch; + chip->ecc.correct = rawnand_sw_bch_correct; + chip->ecc.calculate = omap_calculate_ecc_bch_sw; + mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops); + /* Reserve one byte for the OMAP marker */ + oobbytes_per_step = chip->ecc.bytes + 1; + /* Software BCH library is used for locating errors */ + err = rawnand_sw_bch_init(chip); + if (err) { + dev_err(dev, "Unable to use BCH library\n"); + return err; + } + break; + + case OMAP_ECC_BCH4_CODE_HW: + pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n"); + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.size = 512; + /* 14th bit is kept reserved for ROM-code compatibility */ + chip->ecc.bytes = 7 + 1; + chip->ecc.strength = 4; + chip->ecc.hwctl = omap_enable_hwecc_bch; + chip->ecc.correct = omap_elm_correct_data; + chip->ecc.read_page = omap_read_page_bch; + chip->ecc.write_page = omap_write_page_bch; + chip->ecc.write_subpage = omap_write_subpage_bch; + mtd_set_ooblayout(mtd, &omap_ooblayout_ops); + oobbytes_per_step = chip->ecc.bytes; + elm_bch_strength = BCH4_ECC; + break; + + case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW: + pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n"); + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.size = 512; + chip->ecc.bytes = 13; + chip->ecc.strength = 8; + chip->ecc.hwctl = omap_enable_hwecc_bch; + chip->ecc.correct = rawnand_sw_bch_correct; + chip->ecc.calculate = omap_calculate_ecc_bch_sw; + mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops); + /* Reserve one byte for the OMAP marker */ + oobbytes_per_step = chip->ecc.bytes + 1; + /* Software BCH library is used for locating errors */ + err = rawnand_sw_bch_init(chip); + if (err) { + dev_err(dev, "unable to use BCH library\n"); + return err; + } + break; + + case OMAP_ECC_BCH8_CODE_HW: + pr_info("nand: using OMAP_ECC_BCH8_CODE_HW ECC scheme\n"); + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.size = 512; + /* 14th bit is kept reserved for ROM-code compatibility */ + chip->ecc.bytes = 13 + 1; + chip->ecc.strength = 8; + chip->ecc.hwctl = omap_enable_hwecc_bch; + chip->ecc.correct = omap_elm_correct_data; + chip->ecc.read_page = omap_read_page_bch; + chip->ecc.write_page = omap_write_page_bch; + chip->ecc.write_subpage = omap_write_subpage_bch; + mtd_set_ooblayout(mtd, &omap_ooblayout_ops); + oobbytes_per_step = chip->ecc.bytes; + elm_bch_strength = BCH8_ECC; + break; + + case OMAP_ECC_BCH16_CODE_HW: + pr_info("Using OMAP_ECC_BCH16_CODE_HW ECC scheme\n"); + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; + chip->ecc.size = 512; + chip->ecc.bytes = 26; + chip->ecc.strength = 16; + chip->ecc.hwctl = omap_enable_hwecc_bch; + chip->ecc.correct = omap_elm_correct_data; + chip->ecc.read_page = omap_read_page_bch; + chip->ecc.write_page = omap_write_page_bch; + chip->ecc.write_subpage = omap_write_subpage_bch; + mtd_set_ooblayout(mtd, &omap_ooblayout_ops); + oobbytes_per_step = chip->ecc.bytes; + elm_bch_strength = BCH16_ECC; + break; + default: + dev_err(dev, "Invalid or unsupported ECC scheme\n"); + return -EINVAL; + } + + if (elm_bch_strength >= 0) { + chip->ecc.steps = mtd->writesize / chip->ecc.size; + info->neccpg = chip->ecc.steps / ERROR_VECTOR_MAX; + if (info->neccpg) { + info->nsteps_per_eccpg = ERROR_VECTOR_MAX; + } else { + info->neccpg = 1; + info->nsteps_per_eccpg = chip->ecc.steps; + } + info->eccpg_size = info->nsteps_per_eccpg * chip->ecc.size; + info->eccpg_bytes = info->nsteps_per_eccpg * chip->ecc.bytes; + + err = elm_config(info->elm_dev, elm_bch_strength, + info->nsteps_per_eccpg, chip->ecc.size, + chip->ecc.bytes); + if (err < 0) + return err; + } + + /* Check if NAND device's OOB is enough to store ECC signatures */ + min_oobbytes += (oobbytes_per_step * + (mtd->writesize / chip->ecc.size)); + if (mtd->oobsize < min_oobbytes) { + dev_err(dev, + "Not enough OOB bytes: required = %d, available=%d\n", + min_oobbytes, mtd->oobsize); + return -EINVAL; + } + + return 0; +} + +static void omap_nand_data_in(struct nand_chip *chip, void *buf, + unsigned int len, bool force_8bit) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + u32 alignment = ((uintptr_t)buf | len) & 3; + + if (force_8bit || (alignment & 1)) + ioread8_rep(info->fifo, buf, len); + else if (alignment & 3) + ioread16_rep(info->fifo, buf, len >> 1); + else + ioread32_rep(info->fifo, buf, len >> 2); +} + +static void omap_nand_data_out(struct nand_chip *chip, + const void *buf, unsigned int len, + bool force_8bit) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + u32 alignment = ((uintptr_t)buf | len) & 3; + + if (force_8bit || (alignment & 1)) + iowrite8_rep(info->fifo, buf, len); + else if (alignment & 3) + iowrite16_rep(info->fifo, buf, len >> 1); + else + iowrite32_rep(info->fifo, buf, len >> 2); +} + +static int omap_nand_exec_instr(struct nand_chip *chip, + const struct nand_op_instr *instr) +{ + struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip)); + unsigned int i; + int ret; + + switch (instr->type) { + case NAND_OP_CMD_INSTR: + iowrite8(instr->ctx.cmd.opcode, + info->reg.gpmc_nand_command); + break; + + case NAND_OP_ADDR_INSTR: + for (i = 0; i < instr->ctx.addr.naddrs; i++) { + iowrite8(instr->ctx.addr.addrs[i], + info->reg.gpmc_nand_address); + } + break; + + case NAND_OP_DATA_IN_INSTR: + info->data_in(chip, instr->ctx.data.buf.in, + instr->ctx.data.len, + instr->ctx.data.force_8bit); + break; + + case NAND_OP_DATA_OUT_INSTR: + info->data_out(chip, instr->ctx.data.buf.out, + instr->ctx.data.len, + instr->ctx.data.force_8bit); + break; + + case NAND_OP_WAITRDY_INSTR: + ret = info->ready_gpiod ? + nand_gpio_waitrdy(chip, info->ready_gpiod, instr->ctx.waitrdy.timeout_ms) : + nand_soft_waitrdy(chip, instr->ctx.waitrdy.timeout_ms); + if (ret) + return ret; + break; + } + + if (instr->delay_ns) + ndelay(instr->delay_ns); + + return 0; +} + +static int omap_nand_exec_op(struct nand_chip *chip, + const struct nand_operation *op, + bool check_only) +{ + unsigned int i; + + if (check_only) + return 0; + + for (i = 0; i < op->ninstrs; i++) { + int ret; + + ret = omap_nand_exec_instr(chip, &op->instrs[i]); + if (ret) + return ret; + } + + return 0; +} + +static const struct nand_controller_ops omap_nand_controller_ops = { + .attach_chip = omap_nand_attach_chip, + .exec_op = omap_nand_exec_op, +}; + +/* Shared among all NAND instances to synchronize access to the ECC Engine */ +static struct nand_controller omap_gpmc_controller; +static bool omap_gpmc_controller_initialized; + +static int omap_nand_probe(struct platform_device *pdev) +{ + struct omap_nand_info *info; + struct mtd_info *mtd; + struct nand_chip *nand_chip; + int err; + struct resource *res; + struct device *dev = &pdev->dev; + void __iomem *vaddr; + + info = devm_kzalloc(&pdev->dev, sizeof(struct omap_nand_info), + GFP_KERNEL); + if (!info) + return -ENOMEM; + + info->pdev = pdev; + + err = omap_get_dt_info(dev, info); + if (err) + return err; + + 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_set_flash_node(nand_chip, dev->of_node); + + if (!mtd->name) { + mtd->name = devm_kasprintf(&pdev->dev, GFP_KERNEL, + "omap2-nand.%d", info->gpmc_cs); + if (!mtd->name) { + dev_err(&pdev->dev, "Failed to set MTD name\n"); + return -ENOMEM; + } + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + vaddr = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(vaddr)) + return PTR_ERR(vaddr); + + info->fifo = vaddr; + info->phys_base = res->start; + + if (!omap_gpmc_controller_initialized) { + omap_gpmc_controller.ops = &omap_nand_controller_ops; + nand_controller_init(&omap_gpmc_controller); + omap_gpmc_controller_initialized = true; + } + + nand_chip->controller = &omap_gpmc_controller; + + 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 (info->flash_bbt) + nand_chip->bbt_options |= NAND_BBT_USE_FLASH; + + /* default operations */ + info->data_in = omap_nand_data_in; + info->data_out = omap_nand_data_out; + + err = nand_scan(nand_chip, 1); + if (err) + goto return_error; + + err = mtd_device_register(mtd, NULL, 0); + if (err) + goto cleanup_nand; + + platform_set_drvdata(pdev, mtd); + + return 0; + +cleanup_nand: + nand_cleanup(nand_chip); + +return_error: + if (!IS_ERR_OR_NULL(info->dma)) + dma_release_channel(info->dma); + + rawnand_sw_bch_cleanup(nand_chip); + + 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); + + rawnand_sw_bch_cleanup(nand_chip); + + if (info->dma) + dma_release_channel(info->dma); + WARN_ON(mtd_device_unregister(mtd)); + nand_cleanup(nand_chip); + return 0; +} + +/* omap_nand_ids defined in linux/platform_data/mtd-nand-omap2.h */ +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 = 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"); |