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path: root/drivers/mtd/nand/omap2.c
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Diffstat (limited to 'drivers/mtd/nand/omap2.c')
-rw-r--r--drivers/mtd/nand/omap2.c2120
1 files changed, 2120 insertions, 0 deletions
diff --git a/drivers/mtd/nand/omap2.c b/drivers/mtd/nand/omap2.c
new file mode 100644
index 00000000..e9b1797c
--- /dev/null
+++ b/drivers/mtd/nand/omap2.c
@@ -0,0 +1,2120 @@
+/*
+ * Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com>
+ * 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 <linux/platform_device.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/delay.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.h>
+#include <linux/mtd/partitions.h>
+#include <linux/omap-dma.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+#include <linux/bch.h>
+#include <linux/platform_data/elm.h>
+#endif
+
+#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 OMAP24XX_DMA_GPMC 4
+
+#define BCH8_MAX_ERROR 8 /* upto 8 bit correctable */
+#define BCH4_MAX_ERROR 4 /* upto 4 bit correctable */
+
+#define SECTOR_BYTES 512
+/* 4 bit padding to make byte aligned, 56 = 52 + 4 */
+#define BCH4_BIT_PAD 4
+#define BCH8_ECC_MAX ((SECTOR_BYTES + BCH8_ECC_OOB_BYTES) * 8)
+#define BCH4_ECC_MAX ((SECTOR_BYTES + BCH4_ECC_OOB_BYTES) * 8)
+
+/* 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 */
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+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};
+#endif
+
+/* oob info generated runtime depending on ecc algorithm and layout selected */
+static struct nand_ecclayout omap_oobinfo;
+/* Define some generic bad / good block scan pattern which are used
+ * while scanning a device for factory marked good / bad blocks
+ */
+static uint8_t scan_ff_pattern[] = { 0xff };
+static struct nand_bbt_descr bb_descrip_flashbased = {
+ .options = NAND_BBT_SCANEMPTY | NAND_BBT_SCANALLPAGES,
+ .offs = 0,
+ .len = 1,
+ .pattern = scan_ff_pattern,
+};
+
+
+struct omap_nand_info {
+ struct nand_hw_control controller;
+ struct omap_nand_platform_data *pdata;
+ struct mtd_info mtd;
+ struct nand_chip nand;
+ struct platform_device *pdev;
+
+ int gpmc_cs;
+ unsigned long phys_base;
+ unsigned long mem_size;
+ 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;
+ struct gpmc_nand_regs reg;
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+ struct bch_control *bch;
+ struct nand_ecclayout ecclayout;
+ bool is_elm_used;
+ struct device *elm_dev;
+ struct device_node *of_node;
+#endif
+};
+
+/**
+ * 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) | (0x1 & is_write));
+ 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 = container_of(mtd,
+ struct omap_nand_info, 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->priv;
+
+ 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 = container_of(mtd,
+ struct omap_nand_info, mtd);
+ u_char *p = (u_char *)buf;
+ u32 status = 0;
+
+ while (len--) {
+ iowrite8(*p++, info->nand.IO_ADDR_W);
+ /* wait until buffer is available for write */
+ do {
+ status = readl(info->reg.gpmc_status) &
+ STATUS_BUFF_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->priv;
+
+ 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 = container_of(mtd,
+ struct omap_nand_info, mtd);
+ u16 *p = (u16 *) buf;
+ u32 status = 0;
+ /* 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 = readl(info->reg.gpmc_status) &
+ STATUS_BUFF_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 = container_of(mtd,
+ struct omap_nand_info, 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 = container_of(mtd,
+ struct omap_nand_info, 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 = container_of(mtd,
+ struct omap_nand_info, 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 (addr >= high_memory) {
+ struct page *p1;
+
+ if (((size_t)addr & PAGE_MASK) !=
+ ((size_t)(addr + len - 1) & PAGE_MASK))
+ goto out_copy;
+ p1 = vmalloc_to_page(addr);
+ if (!p1)
+ goto out_copy;
+ addr = page_address(p1) + ((size_t)addr & ~PAGE_MASK);
+ }
+
+ 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);
+
+ /* 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;
+
+ init_completion(&info->comp);
+ dma_async_issue_pending(info->dma);
+
+ /* setup and start DMA using dma_addr */
+ 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 = container_of(mtd,
+ struct omap_nand_info, 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 = container_of(mtd,
+ struct omap_nand_info, 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 -1;
+
+ case 11:
+ /* UN-Correctable error */
+ pr_debug("ECC UNCORRECTED_ERROR B\n");
+ return -1;
+
+ 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 -1;
+ }
+}
+
+/**
+ * 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 = container_of(mtd, struct omap_nand_info,
+ 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 = container_of(mtd, struct omap_nand_info,
+ 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 = container_of(mtd, struct omap_nand_info,
+ mtd);
+ struct nand_chip *chip = mtd->priv;
+ 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->priv;
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ 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 - calls the platform specific dev_ready function
+ * @mtd: MTD device structure
+ */
+static int omap_dev_ready(struct mtd_info *mtd)
+{
+ unsigned int val = 0;
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+
+ val = readl(info->reg.gpmc_status);
+
+ if ((val & 0x100) == 0x100) {
+ return 1;
+ } else {
+ return 0;
+ }
+}
+
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+
+/**
+ * omap3_enable_hwecc_bch - Program OMAP3 GPMC to perform BCH ECC correction
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ *
+ * When using BCH, sector size is hardcoded to 512 bytes.
+ * Using wrapping mode 6 both for reading and writing if ELM module not uses
+ * for error correction.
+ * On writing,
+ * eccsize0 = 0 (no additional protected byte in spare area)
+ * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
+ */
+static void omap3_enable_hwecc_bch(struct mtd_info *mtd, int mode)
+{
+ int nerrors;
+ unsigned int dev_width, nsectors;
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ struct nand_chip *chip = mtd->priv;
+ u32 val, wr_mode;
+ unsigned int ecc_size1, ecc_size0;
+
+ /* Using wrapping mode 6 for writing */
+ wr_mode = BCH_WRAPMODE_6;
+
+ /*
+ * ECC engine enabled for valid ecc_size0 nibbles
+ * and disabled for ecc_size1 nibbles.
+ */
+ ecc_size0 = BCH_ECC_SIZE0;
+ ecc_size1 = BCH_ECC_SIZE1;
+
+ /* Perform ecc calculation on 512-byte sector */
+ nsectors = 1;
+
+ /* Update number of error correction */
+ nerrors = info->nand.ecc.strength;
+
+ /* Multi sector reading/writing for NAND flash with page size < 4096 */
+ if (info->is_elm_used && (mtd->writesize <= 4096)) {
+ if (mode == NAND_ECC_READ) {
+ /* Using wrapping mode 1 for reading */
+ wr_mode = BCH_WRAPMODE_1;
+
+ /*
+ * ECC engine enabled for ecc_size0 nibbles
+ * and disabled for ecc_size1 nibbles.
+ */
+ ecc_size0 = (nerrors == 8) ?
+ BCH8R_ECC_SIZE0 : BCH4R_ECC_SIZE0;
+ ecc_size1 = (nerrors == 8) ?
+ BCH8R_ECC_SIZE1 : BCH4R_ECC_SIZE1;
+ }
+
+ /* Perform ecc calculation for one page (< 4096) */
+ nsectors = info->nand.ecc.steps;
+ }
+
+ 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 */
+ (((nerrors == 8) ? 1 : 0) << 12) | /* 8 or 4 bits */
+ (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);
+}
+
+/**
+ * omap3_calculate_ecc_bch4 - Generate 7 bytes of ECC bytes
+ * @mtd: MTD device structure
+ * @dat: The pointer to data on which ecc is computed
+ * @ecc_code: The ecc_code buffer
+ */
+static int omap3_calculate_ecc_bch4(struct mtd_info *mtd, const u_char *dat,
+ u_char *ecc_code)
+{
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ unsigned long nsectors, val1, val2;
+ int i;
+
+ nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
+
+ for (i = 0; i < nsectors; i++) {
+
+ /* Read hw-computed remainder */
+ val1 = readl(info->reg.gpmc_bch_result0[i]);
+ val2 = readl(info->reg.gpmc_bch_result1[i]);
+
+ /*
+ * Add constant polynomial to remainder, in order to get an ecc
+ * sequence of 0xFFs for a buffer filled with 0xFFs; and
+ * left-justify the resulting polynomial.
+ */
+ *ecc_code++ = 0x28 ^ ((val2 >> 12) & 0xFF);
+ *ecc_code++ = 0x13 ^ ((val2 >> 4) & 0xFF);
+ *ecc_code++ = 0xcc ^ (((val2 & 0xF) << 4)|((val1 >> 28) & 0xF));
+ *ecc_code++ = 0x39 ^ ((val1 >> 20) & 0xFF);
+ *ecc_code++ = 0x96 ^ ((val1 >> 12) & 0xFF);
+ *ecc_code++ = 0xac ^ ((val1 >> 4) & 0xFF);
+ *ecc_code++ = 0x7f ^ ((val1 & 0xF) << 4);
+ }
+
+ return 0;
+}
+
+/**
+ * omap3_calculate_ecc_bch8 - Generate 13 bytes of ECC bytes
+ * @mtd: MTD device structure
+ * @dat: The pointer to data on which ecc is computed
+ * @ecc_code: The ecc_code buffer
+ */
+static int omap3_calculate_ecc_bch8(struct mtd_info *mtd, const u_char *dat,
+ u_char *ecc_code)
+{
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ unsigned long nsectors, val1, val2, val3, val4;
+ int i;
+
+ nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
+
+ for (i = 0; i < nsectors; i++) {
+
+ /* Read hw-computed remainder */
+ val1 = readl(info->reg.gpmc_bch_result0[i]);
+ val2 = readl(info->reg.gpmc_bch_result1[i]);
+ val3 = readl(info->reg.gpmc_bch_result2[i]);
+ val4 = readl(info->reg.gpmc_bch_result3[i]);
+
+ /*
+ * Add constant polynomial to remainder, in order to get an ecc
+ * sequence of 0xFFs for a buffer filled with 0xFFs.
+ */
+ *ecc_code++ = 0xef ^ (val4 & 0xFF);
+ *ecc_code++ = 0x51 ^ ((val3 >> 24) & 0xFF);
+ *ecc_code++ = 0x2e ^ ((val3 >> 16) & 0xFF);
+ *ecc_code++ = 0x09 ^ ((val3 >> 8) & 0xFF);
+ *ecc_code++ = 0xed ^ (val3 & 0xFF);
+ *ecc_code++ = 0x93 ^ ((val2 >> 24) & 0xFF);
+ *ecc_code++ = 0x9a ^ ((val2 >> 16) & 0xFF);
+ *ecc_code++ = 0xc2 ^ ((val2 >> 8) & 0xFF);
+ *ecc_code++ = 0x97 ^ (val2 & 0xFF);
+ *ecc_code++ = 0x79 ^ ((val1 >> 24) & 0xFF);
+ *ecc_code++ = 0xe5 ^ ((val1 >> 16) & 0xFF);
+ *ecc_code++ = 0x24 ^ ((val1 >> 8) & 0xFF);
+ *ecc_code++ = 0xb5 ^ (val1 & 0xFF);
+ }
+
+ return 0;
+}
+
+/**
+ * omap3_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 omap3_calculate_ecc_bch(struct mtd_info *mtd, const u_char *dat,
+ u_char *ecc_code)
+{
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ unsigned long nsectors, bch_val1, bch_val2, bch_val3, bch_val4;
+ int i, eccbchtsel;
+
+ nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
+ /*
+ * find BCH scheme used
+ * 0 -> BCH4
+ * 1 -> BCH8
+ */
+ eccbchtsel = ((readl(info->reg.gpmc_ecc_config) >> 12) & 0x3);
+
+ for (i = 0; i < nsectors; i++) {
+
+ /* Read hw-computed remainder */
+ bch_val1 = readl(info->reg.gpmc_bch_result0[i]);
+ bch_val2 = readl(info->reg.gpmc_bch_result1[i]);
+ if (eccbchtsel) {
+ bch_val3 = readl(info->reg.gpmc_bch_result2[i]);
+ bch_val4 = readl(info->reg.gpmc_bch_result3[i]);
+ }
+
+ if (eccbchtsel) {
+ /* BCH8 ecc scheme */
+ *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);
+ /*
+ * Setting 14th byte to zero to handle
+ * erased page & maintain compatibility
+ * with RBL
+ */
+ *ecc_code++ = 0x0;
+ } else {
+ /* BCH4 ecc scheme */
+ *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);
+ /*
+ * Setting 8th byte to zero to handle
+ * erased page
+ */
+ *ecc_code++ = 0x0;
+ }
+ }
+
+ 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 error/erased pages non-zero error vector is reported.
+ * In case of non-zero ecc vector, check read_ecc at fixed offset
+ * (x = 13/7 in case of BCH8/4 == 0) to find page programmed or not.
+ * To handle bit flips in this data, count the number of 0's in
+ * read_ecc[x] and check if it greater than 4. If it is less, it is
+ * programmed page, else erased page.
+ *
+ * 1. If page is erased, check with standard ecc vector (ecc vector
+ * for erased page to find any bit flip). If check fails, bit flip
+ * is present in erased page. Count the bit flips in erased page and
+ * if it falls under correctable level, report page with 0xFF and
+ * update the correctable bit information.
+ * 2. If error is reported on programmed page, update elm error
+ * vector and correct the page with ELM error correction routine.
+ *
+ */
+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 = container_of(mtd, struct omap_nand_info,
+ mtd);
+ int eccsteps = info->nand.ecc.steps;
+ int i , j, stat = 0;
+ int eccsize, eccflag, ecc_vector_size;
+ 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;
+ enum bch_ecc type;
+ bool is_error_reported = false;
+
+ /* Initialize elm error vector to zero */
+ memset(err_vec, 0, sizeof(err_vec));
+
+ if (info->nand.ecc.strength == BCH8_MAX_ERROR) {
+ type = BCH8_ECC;
+ erased_ecc_vec = bch8_vector;
+ } else {
+ type = BCH4_ECC;
+ erased_ecc_vec = bch4_vector;
+ }
+
+ ecc_vector_size = info->nand.ecc.bytes;
+
+ /*
+ * Remove extra byte padding for BCH8 RBL
+ * compatibility and erased page handling
+ */
+ eccsize = ecc_vector_size - 1;
+
+ 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 < eccsize); j++) {
+ if (calc_ecc[j] != 0) {
+ eccflag = 1; /* non zero ecc, error present */
+ break;
+ }
+ }
+
+ if (eccflag == 1) {
+ /*
+ * Set threshold to minimum of 4, half of ecc.strength/2
+ * to allow max bit flip in byte to 4
+ */
+ unsigned int threshold = min_t(unsigned int, 4,
+ info->nand.ecc.strength / 2);
+
+ /*
+ * Check data area is programmed by counting
+ * number of 0's at fixed offset in spare area.
+ * Checking count of 0's against threshold.
+ * In case programmed page expects at least threshold
+ * zeros in byte.
+ * If zeros are less than threshold for programmed page/
+ * zeros are more than threshold erased page, either
+ * case page reported as uncorrectable.
+ */
+ if (hweight8(~read_ecc[eccsize]) >= threshold) {
+ /*
+ * Update elm error vector as
+ * data area is programmed
+ */
+ err_vec[i].error_reported = true;
+ is_error_reported = true;
+ } else {
+ /* Error reported in erased page */
+ int bitflip_count;
+ u_char *buf = &data[info->nand.ecc.size * i];
+
+ if (memcmp(calc_ecc, erased_ecc_vec, eccsize)) {
+ bitflip_count = erased_sector_bitflips(
+ buf, read_ecc, info);
+
+ if (bitflip_count)
+ stat += bitflip_count;
+ else
+ return -EINVAL;
+ }
+ }
+ }
+
+ /* Update the ecc vector */
+ calc_ecc += ecc_vector_size;
+ read_ecc += ecc_vector_size;
+ }
+
+ /* 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);
+
+ for (i = 0; i < eccsteps; i++) {
+ if (err_vec[i].error_reported) {
+ for (j = 0; j < err_vec[i].error_count; j++) {
+ u32 bit_pos, byte_pos, error_max, pos;
+
+ if (type == BCH8_ECC)
+ error_max = BCH8_ECC_MAX;
+ else
+ error_max = BCH4_ECC_MAX;
+
+ if (info->nand.ecc.strength == BCH8_MAX_ERROR)
+ pos = err_vec[i].error_loc[j];
+ else
+ /* Add 4 to take care 4 bit padding */
+ pos = err_vec[i].error_loc[j] +
+ BCH4_BIT_PAD;
+
+ /* 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)
+ data[byte_pos] ^= 1 << bit_pos;
+ else
+ spare_ecc[byte_pos - 512] ^=
+ 1 << bit_pos;
+ }
+ /* else, not interested to correct ecc */
+ }
+ }
+
+ /* Update number of correctable errors */
+ stat += err_vec[i].error_count;
+
+ /* Update page data with sector size */
+ data += info->nand.ecc.size;
+ spare_ecc += ecc_vector_size;
+ }
+
+ for (i = 0; i < eccsteps; i++)
+ /* Return error if uncorrectable error present */
+ if (err_vec[i].error_uncorrectable)
+ return -EINVAL;
+
+ return stat;
+}
+
+/**
+ * omap3_correct_data_bch - Decode received data and correct errors
+ * @mtd: MTD device structure
+ * @data: page data
+ * @read_ecc: ecc read from nand flash
+ * @calc_ecc: ecc read from HW ECC registers
+ */
+static int omap3_correct_data_bch(struct mtd_info *mtd, u_char *data,
+ u_char *read_ecc, u_char *calc_ecc)
+{
+ int i, count;
+ /* cannot correct more than 8 errors */
+ unsigned int errloc[8];
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+
+ count = decode_bch(info->bch, NULL, 512, read_ecc, calc_ecc, NULL,
+ errloc);
+ if (count > 0) {
+ /* correct errors */
+ for (i = 0; i < count; i++) {
+ /* correct data only, not ecc bytes */
+ if (errloc[i] < 8*512)
+ data[errloc[i]/8] ^= 1 << (errloc[i] & 7);
+ pr_debug("corrected bitflip %u\n", errloc[i]);
+ }
+ } else if (count < 0) {
+ pr_err("ecc unrecoverable error\n");
+ }
+ return count;
+}
+
+/**
+ * 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
+ *
+ * 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 i;
+ uint8_t *ecc_calc = chip->buffers->ecccalc;
+ uint32_t *eccpos = chip->ecc.layout->eccpos;
+
+ /* 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]);
+
+ for (i = 0; i < chip->ecc.total; i++)
+ chip->oob_poi[eccpos[i]] = ecc_calc[i];
+
+ /* 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;
+ uint32_t *eccpos = chip->ecc.layout->eccpos;
+ uint8_t *oob = &chip->oob_poi[eccpos[0]];
+ uint32_t oob_pos = mtd->writesize + chip->ecc.layout->eccpos[0];
+ int stat;
+ 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, oob_pos, -1);
+ chip->read_buf(mtd, oob, chip->ecc.total);
+
+ /* Calculate ecc bytes */
+ chip->ecc.calculate(mtd, buf, ecc_calc);
+
+ memcpy(ecc_code, &chip->oob_poi[eccpos[0]], chip->ecc.total);
+
+ 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;
+}
+
+/**
+ * omap3_free_bch - Release BCH ecc resources
+ * @mtd: MTD device structure
+ */
+static void omap3_free_bch(struct mtd_info *mtd)
+{
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ if (info->bch) {
+ free_bch(info->bch);
+ info->bch = NULL;
+ }
+}
+
+/**
+ * omap3_init_bch - Initialize BCH ECC
+ * @mtd: MTD device structure
+ * @ecc_opt: OMAP ECC mode (OMAP_ECC_BCH4_CODE_HW or OMAP_ECC_BCH8_CODE_HW)
+ */
+static int omap3_init_bch(struct mtd_info *mtd, int ecc_opt)
+{
+ int max_errors;
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+#ifdef CONFIG_MTD_NAND_OMAP_BCH8
+ const int hw_errors = BCH8_MAX_ERROR;
+#else
+ const int hw_errors = BCH4_MAX_ERROR;
+#endif
+ enum bch_ecc bch_type;
+ const __be32 *parp;
+ int lenp;
+ struct device_node *elm_node;
+
+ info->bch = NULL;
+
+ max_errors = (ecc_opt == OMAP_ECC_BCH8_CODE_HW) ?
+ BCH8_MAX_ERROR : BCH4_MAX_ERROR;
+ if (max_errors != hw_errors) {
+ pr_err("cannot configure %d-bit BCH ecc, only %d-bit supported",
+ max_errors, hw_errors);
+ goto fail;
+ }
+
+ info->nand.ecc.size = 512;
+ info->nand.ecc.hwctl = omap3_enable_hwecc_bch;
+ info->nand.ecc.mode = NAND_ECC_HW;
+ info->nand.ecc.strength = max_errors;
+
+ if (hw_errors == BCH8_MAX_ERROR)
+ bch_type = BCH8_ECC;
+ else
+ bch_type = BCH4_ECC;
+
+ /* Detect availability of ELM module */
+ parp = of_get_property(info->of_node, "elm_id", &lenp);
+ if ((parp == NULL) && (lenp != (sizeof(void *) * 2))) {
+ pr_err("Missing elm_id property, fall back to Software BCH\n");
+ info->is_elm_used = false;
+ } else {
+ struct platform_device *pdev;
+
+ elm_node = of_find_node_by_phandle(be32_to_cpup(parp));
+ pdev = of_find_device_by_node(elm_node);
+ info->elm_dev = &pdev->dev;
+
+ if (elm_config(info->elm_dev, bch_type) == 0)
+ info->is_elm_used = true;
+ }
+
+ if (info->is_elm_used && (mtd->writesize <= 4096)) {
+
+ if (hw_errors == BCH8_MAX_ERROR)
+ info->nand.ecc.bytes = BCH8_SIZE;
+ else
+ info->nand.ecc.bytes = BCH4_SIZE;
+
+ info->nand.ecc.correct = omap_elm_correct_data;
+ info->nand.ecc.calculate = omap3_calculate_ecc_bch;
+ info->nand.ecc.read_page = omap_read_page_bch;
+ info->nand.ecc.write_page = omap_write_page_bch;
+ } else {
+ /*
+ * software bch library is only used to detect and
+ * locate errors
+ */
+ info->bch = init_bch(13, max_errors,
+ 0x201b /* hw polynomial */);
+ if (!info->bch)
+ goto fail;
+
+ info->nand.ecc.correct = omap3_correct_data_bch;
+
+ /*
+ * The number of corrected errors in an ecc block that will
+ * trigger block scrubbing defaults to the ecc strength (4 or 8)
+ * Set mtd->bitflip_threshold here to define a custom threshold.
+ */
+
+ if (max_errors == 8) {
+ info->nand.ecc.bytes = 13;
+ info->nand.ecc.calculate = omap3_calculate_ecc_bch8;
+ } else {
+ info->nand.ecc.bytes = 7;
+ info->nand.ecc.calculate = omap3_calculate_ecc_bch4;
+ }
+ }
+
+ pr_info("enabling NAND BCH ecc with %d-bit correction\n", max_errors);
+ return 0;
+fail:
+ omap3_free_bch(mtd);
+ return -1;
+}
+
+/**
+ * omap3_init_bch_tail - Build an oob layout for BCH ECC correction.
+ * @mtd: MTD device structure
+ */
+static int omap3_init_bch_tail(struct mtd_info *mtd)
+{
+ int i, steps, offset;
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ struct nand_ecclayout *layout = &info->ecclayout;
+
+ /* build oob layout */
+ steps = mtd->writesize/info->nand.ecc.size;
+ layout->eccbytes = steps*info->nand.ecc.bytes;
+
+ /* do not bother creating special oob layouts for small page devices */
+ if (mtd->oobsize < 64) {
+ pr_err("BCH ecc is not supported on small page devices\n");
+ goto fail;
+ }
+
+ /* reserve 2 bytes for bad block marker */
+ if (layout->eccbytes+2 > mtd->oobsize) {
+ pr_err("no oob layout available for oobsize %d eccbytes %u\n",
+ mtd->oobsize, layout->eccbytes);
+ goto fail;
+ }
+
+ /* ECC layout compatible with RBL for BCH8 */
+ if (info->is_elm_used && (info->nand.ecc.bytes == BCH8_SIZE))
+ offset = 2;
+ else
+ offset = mtd->oobsize - layout->eccbytes;
+
+ /* put ecc bytes at oob tail */
+ for (i = 0; i < layout->eccbytes; i++)
+ layout->eccpos[i] = offset + i;
+
+ if (info->is_elm_used && (info->nand.ecc.bytes == BCH8_SIZE))
+ layout->oobfree[0].offset = 2 + layout->eccbytes * steps;
+ else
+ layout->oobfree[0].offset = 2;
+
+ layout->oobfree[0].length = mtd->oobsize-2-layout->eccbytes;
+ info->nand.ecc.layout = layout;
+
+ if (!(info->nand.options & NAND_BUSWIDTH_16))
+ info->nand.badblock_pattern = &bb_descrip_flashbased;
+ return 0;
+fail:
+ omap3_free_bch(mtd);
+ return -1;
+}
+
+#else
+static int omap3_init_bch(struct mtd_info *mtd, int ecc_opt)
+{
+ pr_err("CONFIG_MTD_NAND_OMAP_BCH is not enabled\n");
+ return -1;
+}
+static int omap3_init_bch_tail(struct mtd_info *mtd)
+{
+ return -1;
+}
+static void omap3_free_bch(struct mtd_info *mtd)
+{
+}
+#endif /* CONFIG_MTD_NAND_OMAP_BCH */
+
+static int omap_nand_probe(struct platform_device *pdev)
+{
+ struct omap_nand_info *info;
+ struct omap_nand_platform_data *pdata;
+ int err;
+ int i, offset;
+ dma_cap_mask_t mask;
+ unsigned sig;
+ struct resource *res;
+ struct mtd_part_parser_data ppdata = {};
+
+ pdata = pdev->dev.platform_data;
+ if (pdata == NULL) {
+ dev_err(&pdev->dev, "platform data missing\n");
+ return -ENODEV;
+ }
+
+ info = kzalloc(sizeof(struct omap_nand_info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, info);
+
+ spin_lock_init(&info->controller.lock);
+ init_waitqueue_head(&info->controller.wq);
+
+ info->pdev = pdev;
+
+ info->gpmc_cs = pdata->cs;
+ info->reg = pdata->reg;
+
+ info->mtd.priv = &info->nand;
+ info->mtd.name = dev_name(&pdev->dev);
+ info->mtd.owner = THIS_MODULE;
+
+ info->nand.options = pdata->devsize;
+ info->nand.options |= NAND_SKIP_BBTSCAN;
+#ifdef CONFIG_MTD_NAND_OMAP_BCH
+ info->of_node = pdata->of_node;
+#endif
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (res == NULL) {
+ err = -EINVAL;
+ dev_err(&pdev->dev, "error getting memory resource\n");
+ goto out_free_info;
+ }
+
+ info->phys_base = res->start;
+ info->mem_size = resource_size(res);
+
+ if (!request_mem_region(info->phys_base, info->mem_size,
+ pdev->dev.driver->name)) {
+ err = -EBUSY;
+ goto out_free_info;
+ }
+
+ info->nand.IO_ADDR_R = ioremap(info->phys_base, info->mem_size);
+ if (!info->nand.IO_ADDR_R) {
+ err = -ENOMEM;
+ goto out_release_mem_region;
+ }
+
+ info->nand.controller = &info->controller;
+
+ info->nand.IO_ADDR_W = info->nand.IO_ADDR_R;
+ info->nand.cmd_ctrl = omap_hwcontrol;
+
+ /*
+ * 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 (pdata->dev_ready) {
+ info->nand.dev_ready = omap_dev_ready;
+ info->nand.chip_delay = 0;
+ } else {
+ info->nand.waitfunc = omap_wait;
+ info->nand.chip_delay = 50;
+ }
+
+ switch (pdata->xfer_type) {
+ case NAND_OMAP_PREFETCH_POLLED:
+ info->nand.read_buf = omap_read_buf_pref;
+ info->nand.write_buf = omap_write_buf_pref;
+ break;
+
+ case NAND_OMAP_POLLED:
+ if (info->nand.options & NAND_BUSWIDTH_16) {
+ info->nand.read_buf = omap_read_buf16;
+ info->nand.write_buf = omap_write_buf16;
+ } else {
+ info->nand.read_buf = omap_read_buf8;
+ info->nand.write_buf = omap_write_buf8;
+ }
+ break;
+
+ case NAND_OMAP_PREFETCH_DMA:
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+ sig = OMAP24XX_DMA_GPMC;
+ info->dma = dma_request_channel(mask, omap_dma_filter_fn, &sig);
+ if (!info->dma) {
+ dev_err(&pdev->dev, "DMA engine request failed\n");
+ err = -ENXIO;
+ goto out_release_mem_region;
+ } 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 out_release_mem_region;
+ }
+ info->nand.read_buf = omap_read_buf_dma_pref;
+ info->nand.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 out_release_mem_region;
+ }
+ err = request_irq(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 out_release_mem_region;
+ }
+
+ 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 out_release_mem_region;
+ }
+ err = request_irq(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 out_release_mem_region;
+ }
+
+ info->nand.read_buf = omap_read_buf_irq_pref;
+ info->nand.write_buf = omap_write_buf_irq_pref;
+
+ break;
+
+ default:
+ dev_err(&pdev->dev,
+ "xfer_type(%d) not supported!\n", pdata->xfer_type);
+ err = -EINVAL;
+ goto out_release_mem_region;
+ }
+
+ /* select the ecc type */
+ if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_DEFAULT)
+ info->nand.ecc.mode = NAND_ECC_SOFT;
+ else if ((pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW) ||
+ (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE)) {
+ info->nand.ecc.bytes = 3;
+ info->nand.ecc.size = 512;
+ info->nand.ecc.strength = 1;
+ info->nand.ecc.calculate = omap_calculate_ecc;
+ info->nand.ecc.hwctl = omap_enable_hwecc;
+ info->nand.ecc.correct = omap_correct_data;
+ info->nand.ecc.mode = NAND_ECC_HW;
+ } else if ((pdata->ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
+ (pdata->ecc_opt == OMAP_ECC_BCH8_CODE_HW)) {
+ err = omap3_init_bch(&info->mtd, pdata->ecc_opt);
+ if (err) {
+ err = -EINVAL;
+ goto out_release_mem_region;
+ }
+ }
+
+ /* DIP switches on some boards change between 8 and 16 bit
+ * bus widths for flash. Try the other width if the first try fails.
+ */
+ if (nand_scan_ident(&info->mtd, 1, NULL)) {
+ info->nand.options ^= NAND_BUSWIDTH_16;
+ if (nand_scan_ident(&info->mtd, 1, NULL)) {
+ err = -ENXIO;
+ goto out_release_mem_region;
+ }
+ }
+
+ /* rom code layout */
+ if (pdata->ecc_opt == OMAP_ECC_HAMMING_CODE_HW_ROMCODE) {
+
+ if (info->nand.options & NAND_BUSWIDTH_16)
+ offset = 2;
+ else {
+ offset = 1;
+ info->nand.badblock_pattern = &bb_descrip_flashbased;
+ }
+ omap_oobinfo.eccbytes = 3 * (info->mtd.oobsize/16);
+ for (i = 0; i < omap_oobinfo.eccbytes; i++)
+ omap_oobinfo.eccpos[i] = i+offset;
+
+ omap_oobinfo.oobfree->offset = offset + omap_oobinfo.eccbytes;
+ omap_oobinfo.oobfree->length = info->mtd.oobsize -
+ (offset + omap_oobinfo.eccbytes);
+
+ info->nand.ecc.layout = &omap_oobinfo;
+ } else if ((pdata->ecc_opt == OMAP_ECC_BCH4_CODE_HW) ||
+ (pdata->ecc_opt == OMAP_ECC_BCH8_CODE_HW)) {
+ /* build OOB layout for BCH ECC correction */
+ err = omap3_init_bch_tail(&info->mtd);
+ if (err) {
+ err = -EINVAL;
+ goto out_release_mem_region;
+ }
+ }
+
+ /* second phase scan */
+ if (nand_scan_tail(&info->mtd)) {
+ err = -ENXIO;
+ goto out_release_mem_region;
+ }
+
+ ppdata.of_node = pdata->of_node;
+ mtd_device_parse_register(&info->mtd, NULL, &ppdata, pdata->parts,
+ pdata->nr_parts);
+
+ platform_set_drvdata(pdev, &info->mtd);
+
+ return 0;
+
+out_release_mem_region:
+ if (info->dma)
+ dma_release_channel(info->dma);
+ if (info->gpmc_irq_count > 0)
+ free_irq(info->gpmc_irq_count, info);
+ if (info->gpmc_irq_fifo > 0)
+ free_irq(info->gpmc_irq_fifo, info);
+ release_mem_region(info->phys_base, info->mem_size);
+out_free_info:
+ kfree(info);
+
+ return err;
+}
+
+static int omap_nand_remove(struct platform_device *pdev)
+{
+ struct mtd_info *mtd = platform_get_drvdata(pdev);
+ struct omap_nand_info *info = container_of(mtd, struct omap_nand_info,
+ mtd);
+ omap3_free_bch(&info->mtd);
+
+ platform_set_drvdata(pdev, NULL);
+ if (info->dma)
+ dma_release_channel(info->dma);
+
+ if (info->gpmc_irq_count > 0)
+ free_irq(info->gpmc_irq_count, info);
+ if (info->gpmc_irq_fifo > 0)
+ free_irq(info->gpmc_irq_fifo, info);
+
+ /* Release NAND device, its internal structures and partitions */
+ nand_release(&info->mtd);
+ iounmap(info->nand.IO_ADDR_R);
+ release_mem_region(info->phys_base, info->mem_size);
+ kfree(info);
+ return 0;
+}
+
+static struct platform_driver omap_nand_driver = {
+ .probe = omap_nand_probe,
+ .remove = omap_nand_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ },
+};
+
+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");