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Diffstat (limited to 'drivers/mtd/nand/raw/omap_gpmc.c')
-rw-r--r--drivers/mtd/nand/raw/omap_gpmc.c1290
1 files changed, 1290 insertions, 0 deletions
diff --git a/drivers/mtd/nand/raw/omap_gpmc.c b/drivers/mtd/nand/raw/omap_gpmc.c
new file mode 100644
index 00000000000..92a92ad63a0
--- /dev/null
+++ b/drivers/mtd/nand/raw/omap_gpmc.c
@@ -0,0 +1,1290 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2004-2008 Texas Instruments, <www.ti.com>
+ * Rohit Choraria <rohitkc@ti.com>
+ */
+
+#include <config.h>
+#include <log.h>
+#include <system-constants.h>
+#include <asm/io.h>
+#include <dm.h>
+#include <linux/errno.h>
+
+#ifdef CONFIG_ARCH_OMAP2PLUS
+#include <asm/arch/mem.h>
+#endif
+
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/mtd/omap_gpmc.h>
+#include <linux/mtd/nand_ecc.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/bch.h>
+#include <linux/compiler.h>
+#include <nand.h>
+
+#include "omap_elm.h"
+
+#ifndef GPMC_MAX_CS
+#define GPMC_MAX_CS 4
+#endif
+
+#define BADBLOCK_MARKER_LENGTH 2
+#define SECTOR_BYTES 512
+#define ECCSIZE0_SHIFT 12
+#define ECCSIZE1_SHIFT 22
+#define ECC1RESULTSIZE 0x1
+#define ECCCLEAR (0x1 << 8)
+#define ECCRESULTREG1 (0x1 << 0)
+/* 4 bit padding to make byte aligned, 56 = 52 + 4 */
+#define BCH4_BIT_PAD 4
+
+#ifdef CONFIG_BCH
+static u8 bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,
+ 0x97, 0x79, 0xe5, 0x24, 0xb5};
+#endif
+static uint8_t cs_next;
+
+#if defined(CONFIG_NAND_OMAP_GPMC_WSCFG)
+static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE] =
+ { CONFIG_NAND_OMAP_GPMC_WSCFG };
+#else
+/* wscfg is preset to zero since its a static variable */
+static const int8_t wscfg[CONFIG_SYS_MAX_NAND_DEVICE];
+#endif
+
+/*
+ * Driver configurations
+ */
+struct omap_nand_info {
+ struct bch_control *control;
+ enum omap_ecc ecc_scheme;
+ uint8_t cs;
+ uint8_t ws; /* wait status pin (0,1) */
+ void __iomem *fifo;
+};
+
+/* We are wasting a bit of memory but al least we are safe */
+static struct omap_nand_info omap_nand_info[GPMC_MAX_CS];
+
+/*
+ * omap_nand_hwcontrol - Set the address pointers corretly for the
+ * following address/data/command operation
+ */
+static void omap_nand_hwcontrol(struct mtd_info *mtd, int32_t cmd,
+ uint32_t ctrl)
+{
+ register struct nand_chip *this = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(this);
+ int cs = info->cs;
+
+ /*
+ * Point the IO_ADDR to DATA and ADDRESS registers instead
+ * of chip address
+ */
+ switch (ctrl) {
+ case NAND_CTRL_CHANGE | NAND_CTRL_CLE:
+ this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
+ break;
+ case NAND_CTRL_CHANGE | NAND_CTRL_ALE:
+ this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_adr;
+ break;
+ case NAND_CTRL_CHANGE | NAND_NCE:
+ this->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
+ break;
+ }
+
+ if (cmd != NAND_CMD_NONE)
+ writeb(cmd, this->IO_ADDR_W);
+}
+
+/* Check wait pin as dev ready indicator */
+static int omap_dev_ready(struct mtd_info *mtd)
+{
+ register struct nand_chip *this = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(this);
+ return gpmc_cfg->status & (1 << (8 + info->ws));
+}
+
+/*
+ * gen_true_ecc - This function will generate true ECC value, which
+ * can be used when correcting data read from NAND flash memory core
+ *
+ * @ecc_buf: buffer to store ecc code
+ *
+ * @return: re-formatted ECC value
+ */
+static uint32_t gen_true_ecc(uint8_t *ecc_buf)
+{
+ return ecc_buf[0] | (ecc_buf[1] << 16) | ((ecc_buf[2] & 0xF0) << 20) |
+ ((ecc_buf[2] & 0x0F) << 8);
+}
+
+/*
+ * omap_correct_data - Compares the ecc read from nand spare area with ECC
+ * registers values and corrects one bit error if it has occurred
+ * Further details can be had from OMAP TRM and the following selected links:
+ * http://en.wikipedia.org/wiki/Hamming_code
+ * http://www.cs.utexas.edu/users/plaxton/c/337/05f/slides/ErrorCorrection-4.pdf
+ *
+ * @mtd: MTD device structure
+ * @dat: page data
+ * @read_ecc: ecc read from nand flash
+ * @calc_ecc: ecc read from ECC registers
+ *
+ * Return: 0 if data is OK or corrected, else returns -1
+ */
+static int __maybe_unused omap_correct_data(struct mtd_info *mtd, uint8_t *dat,
+ uint8_t *read_ecc, uint8_t *calc_ecc)
+{
+ uint32_t orig_ecc, new_ecc, res, hm;
+ uint16_t parity_bits, byte;
+ uint8_t bit;
+
+ /* Regenerate the orginal ECC */
+ orig_ecc = gen_true_ecc(read_ecc);
+ new_ecc = gen_true_ecc(calc_ecc);
+ /* Get the XOR of real ecc */
+ res = orig_ecc ^ new_ecc;
+ if (res) {
+ /* Get the hamming width */
+ hm = hweight32(res);
+ /* Single bit errors can be corrected! */
+ if (hm == 12) {
+ /* Correctable data! */
+ parity_bits = res >> 16;
+ bit = (parity_bits & 0x7);
+ byte = (parity_bits >> 3) & 0x1FF;
+ /* Flip the bit to correct */
+ dat[byte] ^= (0x1 << bit);
+ } else if (hm == 1) {
+ printf("Error: Ecc is wrong\n");
+ /* ECC itself is corrupted */
+ return 2;
+ } else {
+ /*
+ * hm distance != parity pairs OR one, could mean 2 bit
+ * error OR potentially be on a blank page..
+ * orig_ecc: contains spare area data from nand flash.
+ * new_ecc: generated ecc while reading data area.
+ * Note: if the ecc = 0, all data bits from which it was
+ * generated are 0xFF.
+ * The 3 byte(24 bits) ecc is generated per 512byte
+ * chunk of a page. If orig_ecc(from spare area)
+ * is 0xFF && new_ecc(computed now from data area)=0x0,
+ * this means that data area is 0xFF and spare area is
+ * 0xFF. A sure sign of a erased page!
+ */
+ if ((orig_ecc == 0x0FFF0FFF) && (new_ecc == 0x00000000))
+ return 0;
+ printf("Error: Bad compare! failed\n");
+ /* detected 2 bit error */
+ return -EBADMSG;
+ }
+ }
+ return 0;
+}
+
+/*
+ * omap_enable_hwecc - configures GPMC as per ECC scheme before read/write
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ */
+__maybe_unused
+static void omap_enable_hwecc(struct mtd_info *mtd, int32_t mode)
+{
+ struct nand_chip *nand = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(nand);
+ unsigned int dev_width = (nand->options & NAND_BUSWIDTH_16) ? 1 : 0;
+ u32 val;
+
+ /* Clear ecc and enable bits */
+ writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
+
+ /* program ecc and result sizes */
+ val = ((((nand->ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
+ ECC1RESULTSIZE);
+ writel(val, &gpmc_cfg->ecc_size_config);
+
+ switch (mode) {
+ case NAND_ECC_READ:
+ case NAND_ECC_WRITE:
+ writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
+ break;
+ case NAND_ECC_READSYN:
+ writel(ECCCLEAR, &gpmc_cfg->ecc_control);
+ break;
+ default:
+ printf("%s: error: unrecognized Mode[%d]!\n", __func__, mode);
+ break;
+ }
+
+ /* (ECC 16 or 8 bit col) | ( CS ) | ECC Enable */
+ val = (dev_width << 7) | (info->cs << 1) | (0x1);
+ writel(val, &gpmc_cfg->ecc_config);
+}
+
+/*
+ * omap_calculate_ecc - Read ECC result
+ * @mtd: MTD structure
+ * @dat: unused
+ * @ecc_code: 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.
+ * E.g. if page is 0xFF (fresh erased), and if HW ECC engine within GPMC
+ * is used, the result of read will be 0x0 while the ECC offsets of the
+ * spare area will be 0xFF which will result in an ECC mismatch.
+ */
+static int omap_calculate_ecc(struct mtd_info *mtd, const uint8_t *dat,
+ uint8_t *ecc_code)
+{
+ u32 val;
+
+ val = readl(&gpmc_cfg->ecc1_result);
+ ecc_code[0] = val & 0xFF;
+ ecc_code[1] = (val >> 16) & 0xFF;
+ ecc_code[2] = ((val >> 8) & 0x0F) | ((val >> 20) & 0xF0);
+
+ return 0;
+}
+
+/* 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 */
+
+/**
+ * omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation
+ * @mtd: MTD device structure
+ * @mode: Read/Write mode
+ *
+ * When using BCH with SW correction (i.e. no ELM), sector size is set
+ * to 512 bytes and we use BCH_WRAPMODE_6 wrapping mode
+ * for both reading and writing with:
+ * eccsize0 = 0 (no additional protected byte in spare area)
+ * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
+ */
+static void __maybe_unused omap_enable_hwecc_bch(struct mtd_info *mtd,
+ int mode)
+{
+ unsigned int bch_type;
+ unsigned int dev_width, nsectors;
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+ u32 val, wr_mode;
+ unsigned int ecc_size1, ecc_size0;
+
+ /* GPMC configurations for calculating ECC */
+ switch (info->ecc_scheme) {
+ 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 = 1;
+ 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 = 1;
+ 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(ECCRESULTREG1, &gpmc_cfg->ecc_control);
+
+ /* Configure ecc size for BCH */
+ val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
+ writel(val, &gpmc_cfg->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->cs << 1) | /* ECC CS */
+ (0x1)); /* enable ECC */
+
+ writel(val, &gpmc_cfg->ecc_config);
+
+ /* Clear ecc and enable bits */
+ writel(ECCCLEAR | ECCRESULTREG1, &gpmc_cfg->ecc_control);
+}
+
+/**
+ * omap_calculate_ecc_bch - Generate BCH ECC bytes for one sector
+ * @mtd: MTD device structure
+ * @dat: The pointer to data on which ecc is computed
+ * @ecc_code: The ecc_code buffer
+ *
+ * Support calculating of BCH4/8/16 ECC vectors for one sector
+ * within a page. Sector number is in @sector.
+ */
+static int __maybe_unused omap_calculate_ecc_bch(struct mtd_info *mtd, const u8 *dat,
+ u8 *ecc_code)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+ const uint32_t *ptr;
+ uint32_t val = 0;
+ int8_t i = 0, j;
+
+ switch (info->ecc_scheme) {
+#ifdef CONFIG_BCH
+ case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
+#endif
+ case OMAP_ECC_BCH8_CODE_HW:
+ ptr = &gpmc_cfg->bch_result_0_3[0].bch_result_x[3];
+ val = readl(ptr);
+ ecc_code[i++] = (val >> 0) & 0xFF;
+ ptr--;
+ for (j = 0; j < 3; j++) {
+ val = readl(ptr);
+ ecc_code[i++] = (val >> 24) & 0xFF;
+ ecc_code[i++] = (val >> 16) & 0xFF;
+ ecc_code[i++] = (val >> 8) & 0xFF;
+ ecc_code[i++] = (val >> 0) & 0xFF;
+ ptr--;
+ }
+
+ break;
+ case OMAP_ECC_BCH16_CODE_HW:
+ val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[2]);
+ ecc_code[i++] = (val >> 8) & 0xFF;
+ ecc_code[i++] = (val >> 0) & 0xFF;
+ val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[1]);
+ ecc_code[i++] = (val >> 24) & 0xFF;
+ ecc_code[i++] = (val >> 16) & 0xFF;
+ ecc_code[i++] = (val >> 8) & 0xFF;
+ ecc_code[i++] = (val >> 0) & 0xFF;
+ val = readl(&gpmc_cfg->bch_result_4_6[0].bch_result_x[0]);
+ ecc_code[i++] = (val >> 24) & 0xFF;
+ ecc_code[i++] = (val >> 16) & 0xFF;
+ ecc_code[i++] = (val >> 8) & 0xFF;
+ ecc_code[i++] = (val >> 0) & 0xFF;
+ for (j = 3; j >= 0; j--) {
+ val = readl(&gpmc_cfg->bch_result_0_3[0].bch_result_x[j]
+ );
+ ecc_code[i++] = (val >> 24) & 0xFF;
+ ecc_code[i++] = (val >> 16) & 0xFF;
+ ecc_code[i++] = (val >> 8) & 0xFF;
+ ecc_code[i++] = (val >> 0) & 0xFF;
+ }
+ break;
+ default:
+ return -EINVAL;
+ }
+ /* ECC scheme specific syndrome customizations */
+ switch (info->ecc_scheme) {
+#ifdef CONFIG_BCH
+ 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 (i = 0; i < chip->ecc.bytes; i++)
+ ecc_code[i] ^= bch8_polynomial[i];
+ break;
+#endif
+ case OMAP_ECC_BCH8_CODE_HW:
+ /* Set 14th ECC byte as 0x0 for ROM compatibility */
+ ecc_code[chip->ecc.bytes - 1] = 0x0;
+ break;
+ case OMAP_ECC_BCH16_CODE_HW:
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static inline void omap_nand_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+ u32 alignment = ((uintptr_t)buf | len) & 3;
+
+ if (alignment & 1)
+ readsb(info->fifo, buf, len);
+ else if (alignment & 3)
+ readsw(info->fifo, buf, len >> 1);
+ else
+ readsl(info->fifo, buf, len >> 2);
+}
+
+#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
+
+#define PREFETCH_CONFIG1_CS_SHIFT 24
+#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 ENABLE_PREFETCH (1 << 7)
+
+/**
+ * omap_prefetch_enable - configures and starts prefetch transfer
+ * @fifo_th: fifo threshold to be used for read/ write
+ * @count: number of bytes to be transferred
+ * @is_write: prefetch read(0) or write post(1) mode
+ * @cs: chip select to use
+ */
+static int omap_prefetch_enable(int fifo_th, unsigned int count, int is_write, int cs)
+{
+ uint32_t val;
+
+ if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
+ return -EINVAL;
+
+ if (readl(&gpmc_cfg->prefetch_control))
+ return -EBUSY;
+
+ /* Set the amount of bytes to be prefetched */
+ writel(count, &gpmc_cfg->prefetch_config2);
+
+ val = (cs << PREFETCH_CONFIG1_CS_SHIFT) | (is_write & 1) |
+ PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH;
+ writel(val, &gpmc_cfg->prefetch_config1);
+
+ /* Start the prefetch engine */
+ writel(1, &gpmc_cfg->prefetch_control);
+
+ return 0;
+}
+
+/**
+ * omap_prefetch_reset - disables and stops the prefetch engine
+ */
+static void omap_prefetch_reset(void)
+{
+ writel(0, &gpmc_cfg->prefetch_control);
+ writel(0, &gpmc_cfg->prefetch_config1);
+}
+
+static int __read_prefetch_aligned(struct nand_chip *chip, uint32_t *buf, int len)
+{
+ int ret;
+ uint32_t cnt;
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+
+ ret = omap_prefetch_enable(PREFETCH_FIFOTHRESHOLD_MAX, len, 0, info->cs);
+ if (ret < 0)
+ return ret;
+
+ do {
+ int i;
+
+ cnt = readl(&gpmc_cfg->prefetch_status);
+ cnt = PREFETCH_STATUS_FIFO_CNT(cnt);
+
+ for (i = 0; i < cnt / 4; i++) {
+ *buf++ = readl(info->fifo);
+ len -= 4;
+ }
+ } while (len);
+
+ omap_prefetch_reset();
+
+ return 0;
+}
+
+static void omap_nand_read_prefetch(struct mtd_info *mtd, uint8_t *buf, int len)
+{
+ int ret;
+ uintptr_t head, tail;
+ struct nand_chip *chip = mtd_to_nand(mtd);
+
+ /*
+ * If the destination buffer is unaligned, start with reading
+ * the overlap byte-wise.
+ */
+ head = ((uintptr_t)buf) % 4;
+ if (head) {
+ omap_nand_read_buf(mtd, buf, head);
+ buf += head;
+ len -= head;
+ }
+
+ /*
+ * Only transfer multiples of 4 bytes in a pre-fetched fashion.
+ * If there's a residue, care for it byte-wise afterwards.
+ */
+ tail = len % 4;
+
+ ret = __read_prefetch_aligned(chip, (uint32_t *)buf, len - tail);
+ if (ret < 0) {
+ /* fallback in case the prefetch engine is busy */
+ omap_nand_read_buf(mtd, buf, len);
+ } else if (tail) {
+ buf += len - tail;
+ omap_nand_read_buf(mtd, buf, tail);
+ }
+}
+#endif /* CONFIG_NAND_OMAP_GPMC_PREFETCH */
+
+#ifdef CONFIG_NAND_OMAP_ELM
+
+/*
+ * omap_reverse_list - re-orders list elements in reverse order [internal]
+ * @list: pointer to start of list
+ * @length: length of list
+*/
+static void omap_reverse_list(u8 *list, unsigned int length)
+{
+ unsigned int i, j;
+ unsigned int half_length = length / 2;
+ u8 tmp;
+ for (i = 0, j = length - 1; i < half_length; i++, j--) {
+ tmp = list[i];
+ list[i] = list[j];
+ list[j] = tmp;
+ }
+}
+
+/*
+ * omap_correct_data_bch - Compares the ecc read from nand spare area
+ * with ECC registers values and corrects one bit error if it has occurred
+ *
+ * @mtd: MTD device structure
+ * @dat: page data
+ * @read_ecc: ecc read from nand flash (ignored)
+ * @calc_ecc: ecc read from ECC registers
+ *
+ * Return: 0 if data is OK or corrected, else returns -1
+ */
+static int omap_correct_data_bch(struct mtd_info *mtd, uint8_t *dat,
+ uint8_t *read_ecc, uint8_t *calc_ecc)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+ struct nand_ecc_ctrl *ecc = &chip->ecc;
+ uint32_t error_count = 0, error_max;
+ uint32_t error_loc[ELM_MAX_ERROR_COUNT];
+ enum bch_level bch_type;
+ uint32_t i, ecc_flag = 0;
+ uint8_t count;
+ uint32_t byte_pos, bit_pos;
+ int err = 0;
+
+ /* check calculated ecc */
+ for (i = 0; i < ecc->bytes && !ecc_flag; i++) {
+ if (calc_ecc[i] != 0x00)
+ goto not_ecc_match;
+ }
+ return 0;
+not_ecc_match:
+
+ /* check for whether it's an erased-page */
+ for (i = 0; i < ecc->bytes; i++) {
+ if (read_ecc[i] != 0xff)
+ goto not_erased;
+ }
+ for (i = 0; i < SECTOR_BYTES; i++) {
+ if (dat[i] != 0xff)
+ goto not_erased;
+ }
+ return 0;
+not_erased:
+
+ /*
+ * Check for whether it's an erased page with a correctable
+ * number of bitflips. Erased pages have all 1's in the data,
+ * so we just compute the number of 0 bits in the data and
+ * see if it's under the correction threshold.
+ *
+ * NOTE: The check for a perfect erased page above is faster for
+ * the more common case, even though it's logically redundant.
+ */
+ for (i = 0; i < ecc->bytes; i++)
+ error_count += hweight8(~read_ecc[i]);
+
+ for (i = 0; i < SECTOR_BYTES; i++)
+ error_count += hweight8(~dat[i]);
+
+ if (error_count <= ecc->strength) {
+ memset(read_ecc, 0xFF, ecc->bytes);
+ memset(dat, 0xFF, SECTOR_BYTES);
+ debug("nand: %u bit-flip(s) corrected in erased page\n",
+ error_count);
+ return error_count;
+ }
+
+ /*
+ * while reading ECC result we read it in big endian.
+ * Hence while loading to ELM we have rotate to get the right endian.
+ */
+ switch (info->ecc_scheme) {
+ case OMAP_ECC_BCH8_CODE_HW:
+ bch_type = BCH_8_BIT;
+ omap_reverse_list(calc_ecc, ecc->bytes - 1);
+ break;
+ case OMAP_ECC_BCH16_CODE_HW:
+ bch_type = BCH_16_BIT;
+ omap_reverse_list(calc_ecc, ecc->bytes);
+ break;
+ default:
+ return -EINVAL;
+ }
+ /* use elm module to check for errors */
+ elm_config(bch_type);
+ error_count = 0;
+ err = elm_check_error(calc_ecc, bch_type, &error_count, error_loc);
+ if (err)
+ return err;
+
+ /* correct bch error */
+ for (count = 0; count < error_count; count++) {
+ switch (info->ecc_scheme) {
+ case OMAP_ECC_BCH8_CODE_HW:
+ /* 14th byte in ECC is reserved to match ROM layout */
+ error_max = SECTOR_BYTES + (ecc->bytes - 1);
+ break;
+ case OMAP_ECC_BCH16_CODE_HW:
+ error_max = SECTOR_BYTES + ecc->bytes;
+ break;
+ default:
+ return -EINVAL;
+ }
+ byte_pos = error_max - (error_loc[count] / 8) - 1;
+ bit_pos = error_loc[count] % 8;
+ if (byte_pos < SECTOR_BYTES) {
+ dat[byte_pos] ^= 1 << bit_pos;
+ debug("nand: bit-flip corrected @data=%d\n", byte_pos);
+ } else if (byte_pos < error_max) {
+ read_ecc[byte_pos - SECTOR_BYTES] ^= 1 << bit_pos;
+ debug("nand: bit-flip corrected @oob=%d\n", byte_pos -
+ SECTOR_BYTES);
+ } else {
+ err = -EBADMSG;
+ printf("nand: error: invalid bit-flip location\n");
+ }
+ }
+ return (err) ? err : error_count;
+}
+
+/**
+ * omap_read_page_bch - hardware ecc based page read function
+ * @mtd: mtd info structure
+ * @chip: nand chip info structure
+ * @buf: buffer to store read data
+ * @oob_required: caller expects OOB data read to chip->oob_poi
+ * @page: page number to read
+ *
+ */
+static int omap_read_page_bch(struct mtd_info *mtd, struct nand_chip *chip,
+ uint8_t *buf, int oob_required, int page)
+{
+ int i, eccsize = chip->ecc.size;
+ int eccbytes = chip->ecc.bytes;
+ int eccsteps = chip->ecc.steps;
+ uint8_t *p = buf;
+ 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;
+ uint32_t oob_pos;
+ u32 data_pos = 0;
+
+ /* oob area start */
+ oob_pos = (eccsize * eccsteps) + chip->ecc.layout->eccpos[0];
+ oob += chip->ecc.layout->eccpos[0];
+
+ for (i = 0; eccsteps; eccsteps--, i += eccbytes, p += eccsize,
+ oob += eccbytes) {
+ /* Enable ECC engine */
+ chip->ecc.hwctl(mtd, NAND_ECC_READ);
+
+ /* read data */
+ chip->cmdfunc(mtd, NAND_CMD_RNDOUT, data_pos, -1);
+ chip->read_buf(mtd, p, eccsize);
+
+ /* read respective ecc from oob area */
+ chip->cmdfunc(mtd, NAND_CMD_RNDOUT, oob_pos, -1);
+ chip->read_buf(mtd, oob, eccbytes);
+ /* read syndrome */
+ chip->ecc.calculate(mtd, p, &ecc_calc[i]);
+
+ data_pos += eccsize;
+ oob_pos += eccbytes;
+ }
+
+ for (i = 0; i < chip->ecc.total; i++)
+ ecc_code[i] = chip->oob_poi[eccpos[i]];
+
+ /* error detect & correct */
+ eccsteps = chip->ecc.steps;
+ p = buf;
+
+ for (i = 0 ; eccsteps; eccsteps--, i += eccbytes, p += eccsize) {
+ int stat;
+ stat = chip->ecc.correct(mtd, p, &ecc_code[i], &ecc_calc[i]);
+ if (stat < 0)
+ mtd->ecc_stats.failed++;
+ else
+ mtd->ecc_stats.corrected += stat;
+ }
+
+ return 0;
+}
+#endif /* CONFIG_NAND_OMAP_ELM */
+
+/*
+ * OMAP3 BCH8 support (with BCH library)
+ */
+#ifdef CONFIG_BCH
+/**
+ * omap_correct_data_bch_sw - 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 omap_correct_data_bch_sw(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 nand_chip *chip = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+
+ count = decode_bch(info->control, NULL, SECTOR_BYTES,
+ 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] < SECTOR_BYTES << 3)
+ data[errloc[i] >> 3] ^= 1 << (errloc[i] & 7);
+ debug("corrected bitflip %u\n", errloc[i]);
+#ifdef DEBUG
+ puts("read_ecc: ");
+ /*
+ * BCH8 have 13 bytes of ECC; BCH4 needs adoption
+ * here!
+ */
+ for (i = 0; i < 13; i++)
+ printf("%02x ", read_ecc[i]);
+ puts("\n");
+ puts("calc_ecc: ");
+ for (i = 0; i < 13; i++)
+ printf("%02x ", calc_ecc[i]);
+ puts("\n");
+#endif
+ }
+ } else if (count < 0) {
+ puts("ecc unrecoverable error\n");
+ }
+ return count;
+}
+
+/**
+ * omap_free_bch - Release BCH ecc resources
+ * @mtd: MTD device structure
+ */
+static void __maybe_unused omap_free_bch(struct mtd_info *mtd)
+{
+ struct nand_chip *chip = mtd_to_nand(mtd);
+ struct omap_nand_info *info = nand_get_controller_data(chip);
+
+ if (info->control) {
+ free_bch(info->control);
+ info->control = NULL;
+ }
+}
+#endif /* CONFIG_BCH */
+
+/**
+ * omap_select_ecc_scheme - configures driver for particular ecc-scheme
+ * @nand: NAND chip device structure
+ * @ecc_scheme: ecc scheme to configure
+ * @pagesize: number of main-area bytes per page of NAND device
+ * @oobsize: number of OOB/spare bytes per page of NAND device
+ */
+static int omap_select_ecc_scheme(struct nand_chip *nand,
+ enum omap_ecc ecc_scheme, unsigned int pagesize, unsigned int oobsize) {
+ struct omap_nand_info *info = nand_get_controller_data(nand);
+ struct nand_ecclayout *ecclayout = nand->ecc.layout;
+ int eccsteps = pagesize / SECTOR_BYTES;
+ int i;
+
+ switch (ecc_scheme) {
+ case OMAP_ECC_HAM1_CODE_SW:
+ debug("nand: selected OMAP_ECC_HAM1_CODE_SW\n");
+ /* For this ecc-scheme, ecc.bytes, ecc.layout, ... are
+ * initialized in nand_scan_tail(), so just set ecc.mode */
+ info->control = NULL;
+ nand->ecc.mode = NAND_ECC_SOFT;
+ nand->ecc.layout = NULL;
+ nand->ecc.size = 0;
+ break;
+
+ case OMAP_ECC_HAM1_CODE_HW:
+ debug("nand: selected OMAP_ECC_HAM1_CODE_HW\n");
+ /* check ecc-scheme requirements before updating ecc info */
+ if ((3 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+ printf("nand: error: insufficient OOB: require=%d\n", (
+ (3 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+ return -EINVAL;
+ }
+ info->control = NULL;
+ /* populate ecc specific fields */
+ memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.strength = 1;
+ nand->ecc.size = SECTOR_BYTES;
+ nand->ecc.bytes = 3;
+ nand->ecc.hwctl = omap_enable_hwecc;
+ nand->ecc.correct = omap_correct_data;
+ nand->ecc.calculate = omap_calculate_ecc;
+ /* define ecc-layout */
+ ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
+ for (i = 0; i < ecclayout->eccbytes; i++) {
+ if (nand->options & NAND_BUSWIDTH_16)
+ ecclayout->eccpos[i] = i + 2;
+ else
+ ecclayout->eccpos[i] = i + 1;
+ }
+ ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+ ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
+ BADBLOCK_MARKER_LENGTH;
+ break;
+
+ case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
+#ifdef CONFIG_BCH
+ debug("nand: selected OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
+ /* check ecc-scheme requirements before updating ecc info */
+ if ((13 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+ printf("nand: error: insufficient OOB: require=%d\n", (
+ (13 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+ return -EINVAL;
+ }
+ /* check if BCH S/W library can be used for error detection */
+ info->control = init_bch(13, 8, 0x201b);
+ if (!info->control) {
+ printf("nand: error: could not init_bch()\n");
+ return -ENODEV;
+ }
+ /* populate ecc specific fields */
+ memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.strength = 8;
+ nand->ecc.size = SECTOR_BYTES;
+ nand->ecc.bytes = 13;
+ nand->ecc.hwctl = omap_enable_hwecc_bch;
+ nand->ecc.correct = omap_correct_data_bch_sw;
+ nand->ecc.calculate = omap_calculate_ecc_bch;
+ nand->ecc.steps = eccsteps;
+ /* define ecc-layout */
+ ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
+ ecclayout->eccpos[0] = BADBLOCK_MARKER_LENGTH;
+ for (i = 1; i < ecclayout->eccbytes; i++) {
+ if (i % nand->ecc.bytes)
+ ecclayout->eccpos[i] =
+ ecclayout->eccpos[i - 1] + 1;
+ else
+ ecclayout->eccpos[i] =
+ ecclayout->eccpos[i - 1] + 2;
+ }
+ ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+ ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
+ BADBLOCK_MARKER_LENGTH;
+ break;
+#else
+ printf("nand: error: CONFIG_BCH required for ECC\n");
+ return -EINVAL;
+#endif
+
+ case OMAP_ECC_BCH8_CODE_HW:
+#ifdef CONFIG_NAND_OMAP_ELM
+ debug("nand: selected OMAP_ECC_BCH8_CODE_HW\n");
+ /* check ecc-scheme requirements before updating ecc info */
+ if ((14 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+ printf("nand: error: insufficient OOB: require=%d\n", (
+ (14 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+ return -EINVAL;
+ }
+ /* intialize ELM for ECC error detection */
+ elm_init();
+ info->control = NULL;
+ /* populate ecc specific fields */
+ memset(&nand->ecc, 0, sizeof(struct nand_ecc_ctrl));
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.strength = 8;
+ nand->ecc.size = SECTOR_BYTES;
+ nand->ecc.bytes = 14;
+ nand->ecc.hwctl = omap_enable_hwecc_bch;
+ nand->ecc.correct = omap_correct_data_bch;
+ nand->ecc.calculate = omap_calculate_ecc_bch;
+ nand->ecc.read_page = omap_read_page_bch;
+ nand->ecc.steps = eccsteps;
+ /* define ecc-layout */
+ ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
+ for (i = 0; i < ecclayout->eccbytes; i++)
+ ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
+ ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+ ecclayout->oobfree[0].length = oobsize - ecclayout->eccbytes -
+ BADBLOCK_MARKER_LENGTH;
+ break;
+#else
+ printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
+ return -EINVAL;
+#endif
+
+ case OMAP_ECC_BCH16_CODE_HW:
+#ifdef CONFIG_NAND_OMAP_ELM
+ debug("nand: using OMAP_ECC_BCH16_CODE_HW\n");
+ /* check ecc-scheme requirements before updating ecc info */
+ if ((26 * eccsteps) + BADBLOCK_MARKER_LENGTH > oobsize) {
+ printf("nand: error: insufficient OOB: require=%d\n", (
+ (26 * eccsteps) + BADBLOCK_MARKER_LENGTH));
+ return -EINVAL;
+ }
+ /* intialize ELM for ECC error detection */
+ elm_init();
+ /* populate ecc specific fields */
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.size = SECTOR_BYTES;
+ nand->ecc.bytes = 26;
+ nand->ecc.strength = 16;
+ nand->ecc.hwctl = omap_enable_hwecc_bch;
+ nand->ecc.correct = omap_correct_data_bch;
+ nand->ecc.calculate = omap_calculate_ecc_bch;
+ nand->ecc.read_page = omap_read_page_bch;
+ nand->ecc.steps = eccsteps;
+ /* define ecc-layout */
+ ecclayout->eccbytes = nand->ecc.bytes * eccsteps;
+ for (i = 0; i < ecclayout->eccbytes; i++)
+ ecclayout->eccpos[i] = i + BADBLOCK_MARKER_LENGTH;
+ ecclayout->oobfree[0].offset = i + BADBLOCK_MARKER_LENGTH;
+ ecclayout->oobfree[0].length = oobsize - nand->ecc.bytes -
+ BADBLOCK_MARKER_LENGTH;
+ break;
+#else
+ printf("nand: error: CONFIG_NAND_OMAP_ELM required for ECC\n");
+ return -EINVAL;
+#endif
+ default:
+ debug("nand: error: ecc scheme not enabled or supported\n");
+ return -EINVAL;
+ }
+
+ /* nand_scan_tail() sets ham1 sw ecc; hw ecc layout is set by driver */
+ if (ecc_scheme != OMAP_ECC_HAM1_CODE_SW)
+ nand->ecc.layout = ecclayout;
+
+ info->ecc_scheme = ecc_scheme;
+ return 0;
+}
+
+#ifndef CONFIG_SPL_BUILD
+/*
+ * omap_nand_switch_ecc - switch the ECC operation between different engines
+ * (h/w and s/w) and different algorithms (hamming and BCHx)
+ *
+ * @hardware - true if one of the HW engines should be used
+ * @eccstrength - the number of bits that could be corrected
+ * (1 - hamming, 4 - BCH4, 8 - BCH8, 16 - BCH16)
+ */
+int __maybe_unused omap_nand_switch_ecc(uint32_t hardware, uint32_t eccstrength)
+{
+ struct nand_chip *nand;
+ struct mtd_info *mtd = get_nand_dev_by_index(nand_curr_device);
+ int err = 0;
+
+ if (!mtd) {
+ printf("nand: error: no NAND devices found\n");
+ return -ENODEV;
+ }
+
+ nand = mtd_to_nand(mtd);
+ nand->options |= NAND_OWN_BUFFERS;
+ nand->options &= ~NAND_SUBPAGE_READ;
+ /* Setup the ecc configurations again */
+ if (hardware) {
+ if (eccstrength == 1) {
+ err = omap_select_ecc_scheme(nand,
+ OMAP_ECC_HAM1_CODE_HW,
+ mtd->writesize, mtd->oobsize);
+ } else if (eccstrength == 8) {
+ err = omap_select_ecc_scheme(nand,
+ OMAP_ECC_BCH8_CODE_HW,
+ mtd->writesize, mtd->oobsize);
+ } else if (eccstrength == 16) {
+ err = omap_select_ecc_scheme(nand,
+ OMAP_ECC_BCH16_CODE_HW,
+ mtd->writesize, mtd->oobsize);
+ } else {
+ printf("nand: error: unsupported ECC scheme\n");
+ return -EINVAL;
+ }
+ } else {
+ if (eccstrength == 1) {
+ err = omap_select_ecc_scheme(nand,
+ OMAP_ECC_HAM1_CODE_SW,
+ mtd->writesize, mtd->oobsize);
+ } else if (eccstrength == 8) {
+ err = omap_select_ecc_scheme(nand,
+ OMAP_ECC_BCH8_CODE_HW_DETECTION_SW,
+ mtd->writesize, mtd->oobsize);
+ } else {
+ printf("nand: error: unsupported ECC scheme\n");
+ return -EINVAL;
+ }
+ }
+
+ /* Update NAND handling after ECC mode switch */
+ if (!err)
+ err = nand_scan_tail(mtd);
+ return err;
+}
+#endif /* CONFIG_SPL_BUILD */
+
+/*
+ * Board-specific NAND initialization. The following members of the
+ * argument are board-specific:
+ * - IO_ADDR_R: address to read the 8 I/O lines of the flash device
+ * - IO_ADDR_W: address to write the 8 I/O lines of the flash device
+ * - cmd_ctrl: hardwarespecific function for accesing control-lines
+ * - waitfunc: hardwarespecific function for accesing device ready/busy line
+ * - ecc.hwctl: function to enable (reset) hardware ecc generator
+ * - ecc.mode: mode of ecc, see defines
+ * - chip_delay: chip dependent delay for transfering data from array to
+ * read regs (tR)
+ * - options: various chip options. They can partly be set to inform
+ * nand_scan about special functionality. See the defines for further
+ * explanation
+ */
+int gpmc_nand_init(struct nand_chip *nand, void __iomem *nand_base)
+{
+ int32_t gpmc_config = 0;
+ int cs = cs_next++;
+ int err = 0;
+ struct omap_nand_info *info;
+
+ /*
+ * xloader/Uboot's gpmc configuration would have configured GPMC for
+ * nand type of memory. The following logic scans and latches on to the
+ * first CS with NAND type memory.
+ * TBD: need to make this logic generic to handle multiple CS NAND
+ * devices.
+ */
+ while (cs < GPMC_MAX_CS) {
+ /* Check if NAND type is set */
+ if ((readl(&gpmc_cfg->cs[cs].config1) & 0xC00) == 0x800) {
+ /* Found it!! */
+ break;
+ }
+ cs++;
+ }
+ if (cs >= GPMC_MAX_CS) {
+ printf("nand: error: Unable to find NAND settings in "
+ "GPMC Configuration - quitting\n");
+ return -ENODEV;
+ }
+
+ gpmc_config = readl(&gpmc_cfg->config);
+ /* Disable Write protect */
+ gpmc_config |= 0x10;
+ writel(gpmc_config, &gpmc_cfg->config);
+
+ nand->IO_ADDR_R = (void __iomem *)&gpmc_cfg->cs[cs].nand_dat;
+ nand->IO_ADDR_W = (void __iomem *)&gpmc_cfg->cs[cs].nand_cmd;
+
+ info = &omap_nand_info[cs];
+ info->control = NULL;
+ info->cs = cs;
+ info->ws = wscfg[cs];
+ info->fifo = nand_base;
+ nand_set_controller_data(nand, &omap_nand_info[cs]);
+ nand->cmd_ctrl = omap_nand_hwcontrol;
+ nand->options |= NAND_NO_PADDING | NAND_CACHEPRG;
+ nand->chip_delay = 100;
+ nand->ecc.layout = kzalloc(sizeof(*nand->ecc.layout), GFP_KERNEL);
+ if (!nand->ecc.layout)
+ return -ENOMEM;
+
+ /* configure driver and controller based on NAND device bus-width */
+ gpmc_config = readl(&gpmc_cfg->cs[cs].config1);
+#if defined(CONFIG_SYS_NAND_BUSWIDTH_16BIT)
+ nand->options |= NAND_BUSWIDTH_16;
+ writel(gpmc_config | (0x1 << 12), &gpmc_cfg->cs[cs].config1);
+#else
+ nand->options &= ~NAND_BUSWIDTH_16;
+ writel(gpmc_config & ~(0x1 << 12), &gpmc_cfg->cs[cs].config1);
+#endif
+ /* select ECC scheme */
+#if defined(CONFIG_NAND_OMAP_ECCSCHEME)
+ err = omap_select_ecc_scheme(nand, CONFIG_NAND_OMAP_ECCSCHEME,
+ CONFIG_SYS_NAND_PAGE_SIZE, CONFIG_SYS_NAND_OOBSIZE);
+#else
+ /* pagesize and oobsize are not required to configure sw ecc-scheme */
+ err = omap_select_ecc_scheme(nand, OMAP_ECC_HAM1_CODE_SW,
+ 0, 0);
+#endif
+ if (err)
+ return err;
+
+#ifdef CONFIG_NAND_OMAP_GPMC_PREFETCH
+ nand->read_buf = omap_nand_read_prefetch;
+#else
+ nand->read_buf = omap_nand_read_buf;
+#endif
+
+ nand->dev_ready = omap_dev_ready;
+
+ return 0;
+}
+
+/* First NAND chip for SPL use only */
+static __maybe_unused struct nand_chip *nand_chip;
+
+#if CONFIG_IS_ENABLED(SYS_NAND_SELF_INIT)
+
+static int gpmc_nand_probe(struct udevice *dev)
+{
+ struct nand_chip *nand = dev_get_priv(dev);
+ struct mtd_info *mtd = nand_to_mtd(nand);
+ struct resource res;
+ void __iomem *base;
+ int ret;
+
+ ret = dev_read_resource(dev, 0, &res);
+ if (ret)
+ return ret;
+
+ base = devm_ioremap(dev, res.start, resource_size(&res));
+ gpmc_nand_init(nand, base);
+ mtd->dev = dev;
+ nand_set_flash_node(nand, dev_ofnode(dev));
+
+ ret = nand_scan(mtd, CONFIG_SYS_NAND_MAX_CHIPS);
+ if (ret)
+ return ret;
+
+ ret = nand_register(0, mtd);
+ if (ret)
+ return ret;
+
+ if (!nand_chip)
+ nand_chip = nand;
+
+ return 0;
+}
+
+static const struct udevice_id gpmc_nand_ids[] = {
+ { .compatible = "ti,am64-nand" },
+ { .compatible = "ti,omap2-nand" },
+ { }
+};
+
+U_BOOT_DRIVER(gpmc_nand) = {
+ .name = "gpmc-nand",
+ .id = UCLASS_MTD,
+ .of_match = gpmc_nand_ids,
+ .probe = gpmc_nand_probe,
+ .priv_auto = sizeof(struct nand_chip),
+};
+
+void board_nand_init(void)
+{
+ struct udevice *dev;
+ int ret;
+
+#ifdef CONFIG_NAND_OMAP_ELM
+ ret = uclass_get_device_by_driver(UCLASS_MTD,
+ DM_DRIVER_GET(gpmc_elm), &dev);
+ if (ret && ret != -ENODEV) {
+ pr_err("%s: Failed to get ELM device: %d\n", __func__, ret);
+ return;
+ }
+#endif
+
+ ret = uclass_get_device_by_driver(UCLASS_MTD,
+ DM_DRIVER_GET(gpmc_nand), &dev);
+ if (ret && ret != -ENODEV)
+ pr_err("%s: Failed to get GPMC device: %d\n", __func__, ret);
+}
+
+#else
+
+int board_nand_init(struct nand_chip *nand)
+{
+ return gpmc_nand_init(nand, (void __iomem *)CFG_SYS_NAND_BASE);
+}
+
+#endif /* CONFIG_SYS_NAND_SELF_INIT */
+
+#if defined(CONFIG_SPL_NAND_INIT)
+
+/* nand_init() is provided by nand.c */
+
+/* Unselect after operation */
+void nand_deselect(void)
+{
+ struct mtd_info *mtd = nand_to_mtd(nand_chip);
+
+ if (nand_chip->select_chip)
+ nand_chip->select_chip(mtd, -1);
+}
+
+static int nand_is_bad_block(int block)
+{
+ struct mtd_info *mtd = nand_to_mtd(nand_chip);
+
+ loff_t ofs = block * CONFIG_SYS_NAND_BLOCK_SIZE;
+
+ return nand_chip->block_bad(mtd, ofs);
+}
+
+static int nand_read_page(int block, int page, uchar *dst)
+{
+ int page_addr = block * SYS_NAND_BLOCK_PAGES + page;
+ loff_t ofs = page_addr * CONFIG_SYS_NAND_PAGE_SIZE;
+ int ret;
+ size_t len = CONFIG_SYS_NAND_PAGE_SIZE;
+ struct mtd_info *mtd = nand_to_mtd(nand_chip);
+
+ ret = nand_read(mtd, ofs, &len, dst);
+ if (ret)
+ printf("nand_read failed %d\n", ret);
+
+ return ret;
+}
+
+#include "nand_spl_loaders.c"
+#endif /* CONFIG_SPL_NAND_INIT */