lpc32xx: mtd: nand: add MLC NAND controller
The controller's Reed-Solomon ECC hardware is
used except of course for raw reads and writes.
It covers in- and out-of-band data together.
The SPL framework is supported.
Signed-off-by: Albert ARIBAUD (3ADEV) <albert.aribaud@3adev.fr>
diff --git a/drivers/mtd/nand/lpc32xx_nand_mlc.c b/drivers/mtd/nand/lpc32xx_nand_mlc.c
new file mode 100644
index 0000000..8156fe9
--- /dev/null
+++ b/drivers/mtd/nand/lpc32xx_nand_mlc.c
@@ -0,0 +1,764 @@
+/*
+ * LPC32xx MLC NAND flash controller driver
+ *
+ * (C) Copyright 2014 3ADEV <http://3adev.com>
+ * Written by Albert ARIBAUD <albert.aribaud@3adev.fr>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * NOTE:
+ *
+ * The MLC NAND flash controller provides hardware Reed-Solomon ECC
+ * covering in- and out-of-band data together. Therefore, in- and out-
+ * of-band data must be written together in order to have a valid ECC.
+ *
+ * Consequently, pages with meaningful in-band data are written with
+ * blank (all-ones) out-of-band data and a valid ECC, and any later
+ * out-of-band data write will void the ECC.
+ *
+ * Therefore, code which reads such late-written out-of-band data
+ * should not rely on the ECC validity.
+ */
+
+#include <common.h>
+#include <nand.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <nand.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/sys_proto.h>
+
+/*
+ * MLC NAND controller registers.
+ */
+struct lpc32xx_nand_mlc_registers {
+ u8 buff[32768]; /* controller's serial data buffer */
+ u8 data[32768]; /* NAND's raw data buffer */
+ u32 cmd;
+ u32 addr;
+ u32 ecc_enc_reg;
+ u32 ecc_dec_reg;
+ u32 ecc_auto_enc_reg;
+ u32 ecc_auto_dec_reg;
+ u32 rpr;
+ u32 wpr;
+ u32 rubp;
+ u32 robp;
+ u32 sw_wp_add_low;
+ u32 sw_wp_add_hig;
+ u32 icr;
+ u32 time_reg;
+ u32 irq_mr;
+ u32 irq_sr;
+ u32 lock_pr;
+ u32 isr;
+ u32 ceh;
+};
+
+/* LOCK_PR register defines */
+#define LOCK_PR_UNLOCK_KEY 0x0000A25E /* Magic unlock value */
+
+/* ICR defines */
+#define ICR_LARGE_BLOCKS 0x00000004 /* configure for 2KB blocks */
+#define ICR_ADDR4 0x00000002 /* configure for 4-word addrs */
+
+/* CEH defines */
+#define CEH_NORMAL_CE 0x00000001 /* do not force CE ON */
+
+/* ISR register defines */
+#define ISR_NAND_READY 0x00000001
+#define ISR_CONTROLLER_READY 0x00000002
+#define ISR_ECC_READY 0x00000004
+#define ISR_DECODER_ERRORS(s) ((((s) >> 4) & 3)+1)
+#define ISR_DECODER_FAILURE 0x00000040
+#define ISR_DECODER_ERROR 0x00000008
+
+/* time-out for NAND chip / controller loops, in us */
+#define LPC32X_NAND_TIMEOUT 5000
+
+/*
+ * There is a single instance of the NAND MLC controller
+ */
+
+static struct lpc32xx_nand_mlc_registers __iomem *lpc32xx_nand_mlc_registers
+ = (struct lpc32xx_nand_mlc_registers __iomem *)MLC_NAND_BASE;
+
+#define clkdiv(v, w, o) (((1+(clk/v)) & w) << o)
+
+/**
+ * OOB data in each small page are 6 'free' then 10 ECC bytes.
+ * To make things easier, when reading large pages, the four pages'
+ * 'free' OOB bytes are grouped in the first 24 bytes of the OOB buffer,
+ * while the the four ECC bytes are groupe in its last 40 bytes.
+ *
+ * The struct below represents how free vs ecc oob bytes are stored
+ * in the buffer.
+ *
+ * Note: the OOB bytes contain the bad block marker at offsets 0 and 1.
+ */
+
+struct lpc32xx_oob {
+ struct {
+ uint8_t free_oob_bytes[6];
+ } free[4];
+ struct {
+ uint8_t ecc_oob_bytes[10];
+ } ecc[4];
+};
+
+/*
+ * Initialize the controller
+ */
+
+static void lpc32xx_nand_init(void)
+{
+ unsigned int clk;
+
+ /* Configure controller for no software write protection, x8 bus
+ width, large block device, and 4 address words */
+
+ /* unlock controller registers with magic key */
+ writel(LOCK_PR_UNLOCK_KEY,
+ &lpc32xx_nand_mlc_registers->lock_pr);
+
+ /* enable large blocks and large NANDs */
+ writel(ICR_LARGE_BLOCKS | ICR_ADDR4,
+ &lpc32xx_nand_mlc_registers->icr);
+
+ /* Make sure MLC interrupts are disabled */
+ writel(0, &lpc32xx_nand_mlc_registers->irq_mr);
+
+ /* Normal chip enable operation */
+ writel(CEH_NORMAL_CE,
+ &lpc32xx_nand_mlc_registers->ceh);
+
+ /* Setup NAND timing */
+ clk = get_hclk_clk_rate();
+
+ writel(
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_TCEA_DELAY, 0x03, 24) |
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_BUSY_DELAY, 0x1F, 19) |
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_NAND_TA, 0x07, 16) |
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_RD_HIGH, 0x0F, 12) |
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_RD_LOW, 0x0F, 8) |
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_WR_HIGH, 0x0F, 4) |
+ clkdiv(CONFIG_LPC32XX_NAND_MLC_WR_LOW, 0x0F, 0),
+ &lpc32xx_nand_mlc_registers->time_reg);
+}
+
+#if !defined(CONFIG_SPL_BUILD)
+
+/**
+ * lpc32xx_cmd_ctrl - write command to either cmd or data register
+ */
+
+static void lpc32xx_cmd_ctrl(struct mtd_info *mtd, int cmd,
+ unsigned int ctrl)
+{
+ if (cmd == NAND_CMD_NONE)
+ return;
+
+ if (ctrl & NAND_CLE)
+ writeb(cmd & 0Xff, &lpc32xx_nand_mlc_registers->cmd);
+ else if (ctrl & NAND_ALE)
+ writeb(cmd & 0Xff, &lpc32xx_nand_mlc_registers->addr);
+}
+
+/**
+ * lpc32xx_read_byte - read a byte from the NAND
+ * @mtd: MTD device structure
+ */
+
+static uint8_t lpc32xx_read_byte(struct mtd_info *mtd)
+{
+ return readb(&lpc32xx_nand_mlc_registers->data);
+}
+
+/**
+ * lpc32xx_dev_ready - test if NAND device (actually controller) is ready
+ * @mtd: MTD device structure
+ * @mode: mode to set the ECC HW to.
+ */
+
+static int lpc32xx_dev_ready(struct mtd_info *mtd)
+{
+ /* means *controller* ready for us */
+ int status = readl(&lpc32xx_nand_mlc_registers->isr);
+ return status & ISR_CONTROLLER_READY;
+}
+
+/**
+ * ECC layout -- this is needed whatever ECC mode we are using.
+ * In a 2KB (4*512B) page, R/S codes occupy 40 (4*10) bytes.
+ * To make U-Boot's life easier, we pack 'useable' OOB at the
+ * front and R/S ECC at the back.
+ */
+
+static struct nand_ecclayout lpc32xx_largepage_ecclayout = {
+ .eccbytes = 40,
+ .eccpos = {24, 25, 26, 27, 28, 29, 30, 31, 32, 33,
+ 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,
+ 44, 45, 46, 47, 48, 48, 50, 51, 52, 53,
+ 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ },
+ .oobfree = {
+ /* bytes 0 and 1 are used for the bad block marker */
+ {
+ .offset = 2,
+ .length = 22
+ },
+ }
+};
+
+/**
+ * lpc32xx_read_page_hwecc - read in- and out-of-band data with ECC
+ * @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
+ *
+ * Use large block Auto Decode Read Mode(1) as described in User Manual
+ * section 8.6.2.1.
+ *
+ * The initial Read Mode and Read Start commands are sent by the caller.
+ *
+ * ECC will be false if out-of-band data has been updated since in-band
+ * data was initially written.
+ */
+
+static int lpc32xx_read_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *chip, uint8_t *buf, int oob_required,
+ int page)
+{
+ unsigned int i, status, timeout, err, max_bitflips = 0;
+ struct lpc32xx_oob *oob = (struct lpc32xx_oob *)chip->oob_poi;
+
+ /* go through all four small pages */
+ for (i = 0; i < 4; i++) {
+ /* start auto decode (reads 528 NAND bytes) */
+ writel(0, &lpc32xx_nand_mlc_registers->ecc_auto_dec_reg);
+ /* wait for controller to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_CONTROLLER_READY)
+ break;
+ udelay(1);
+ }
+ /* if decoder failed, return failure */
+ if (status & ISR_DECODER_FAILURE)
+ return -1;
+ /* keep count of maximum bitflips performed */
+ if (status & ISR_DECODER_ERROR) {
+ err = ISR_DECODER_ERRORS(status);
+ if (err > max_bitflips)
+ max_bitflips = err;
+ }
+ /* copy first 512 bytes into buffer */
+ memcpy(buf+512*i, lpc32xx_nand_mlc_registers->buff, 512);
+ /* copy next 6 bytes at front of OOB buffer */
+ memcpy(&oob->free[i], lpc32xx_nand_mlc_registers->buff, 6);
+ /* copy last 10 bytes (R/S ECC) at back of OOB buffer */
+ memcpy(&oob->ecc[i], lpc32xx_nand_mlc_registers->buff, 10);
+ }
+ return max_bitflips;
+}
+
+/**
+ * lpc32xx_read_page_raw - read raw (in-band, out-of-band and ECC) data
+ * @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
+ *
+ * Read NAND directly; can read pages with invalid ECC.
+ */
+
+static int lpc32xx_read_page_raw(struct mtd_info *mtd,
+ struct nand_chip *chip, uint8_t *buf, int oob_required,
+ int page)
+{
+ unsigned int i, status, timeout;
+ struct lpc32xx_oob *oob = (struct lpc32xx_oob *)chip->oob_poi;
+
+ /* when we get here we've already had the Read Mode(1) */
+
+ /* go through all four small pages */
+ for (i = 0; i < 4; i++) {
+ /* wait for NAND to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_NAND_READY)
+ break;
+ udelay(1);
+ }
+ /* if NAND stalled, return failure */
+ if (!(status & ISR_NAND_READY))
+ return -1;
+ /* copy first 512 bytes into buffer */
+ memcpy(buf+512*i, lpc32xx_nand_mlc_registers->data, 512);
+ /* copy next 6 bytes at front of OOB buffer */
+ memcpy(&oob->free[i], lpc32xx_nand_mlc_registers->data, 6);
+ /* copy last 10 bytes (R/S ECC) at back of OOB buffer */
+ memcpy(&oob->ecc[i], lpc32xx_nand_mlc_registers->data, 10);
+ }
+ return 0;
+}
+
+/**
+ * lpc32xx_read_oob - read out-of-band data
+ * @mtd: mtd info structure
+ * @chip: nand chip info structure
+ * @page: page number to read
+ *
+ * Read out-of-band data. User Manual section 8.6.4 suggests using Read
+ * Mode(3) which the controller will turn into a Read Mode(1) internally
+ * but nand_base.c will turn Mode(3) into Mode(0), so let's use Mode(0)
+ * directly.
+ *
+ * ECC covers in- and out-of-band data and was written when out-of-band
+ * data was blank. Therefore, if the out-of-band being read here is not
+ * blank, then the ECC will be false and the read will return bitflips,
+ * even in case of ECC failure where we will return 5 bitflips. The
+ * caller should be prepared to handle this.
+ */
+
+static int lpc32xx_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+ int page)
+{
+ unsigned int i, status, timeout, err, max_bitflips = 0;
+ struct lpc32xx_oob *oob = (struct lpc32xx_oob *)chip->oob_poi;
+
+ /* No command was sent before calling read_oob() so send one */
+
+ chip->cmdfunc(mtd, NAND_CMD_READ0, 0, page);
+
+ /* go through all four small pages */
+ for (i = 0; i < 4; i++) {
+ /* start auto decode (reads 528 NAND bytes) */
+ writel(0, &lpc32xx_nand_mlc_registers->ecc_auto_dec_reg);
+ /* wait for controller to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_CONTROLLER_READY)
+ break;
+ udelay(1);
+ }
+ /* if decoder failure, count 'one too many' bitflips */
+ if (status & ISR_DECODER_FAILURE)
+ max_bitflips = 5;
+ /* keep count of maximum bitflips performed */
+ if (status & ISR_DECODER_ERROR) {
+ err = ISR_DECODER_ERRORS(status);
+ if (err > max_bitflips)
+ max_bitflips = err;
+ }
+ /* set read pointer to OOB area */
+ writel(0, &lpc32xx_nand_mlc_registers->robp);
+ /* copy next 6 bytes at front of OOB buffer */
+ memcpy(&oob->free[i], lpc32xx_nand_mlc_registers->buff, 6);
+ /* copy next 10 bytes (R/S ECC) at back of OOB buffer */
+ memcpy(&oob->ecc[i], lpc32xx_nand_mlc_registers->buff, 10);
+ }
+ return max_bitflips;
+}
+
+/**
+ * lpc32xx_write_page_hwecc - write in- and out-of-band data with ECC
+ * @mtd: mtd info structure
+ * @chip: nand chip info structure
+ * @buf: data buffer
+ * @oob_required: must write chip->oob_poi to OOB
+ *
+ * Use large block Auto Encode as per User Manual section 8.6.4.
+ *
+ * The initial Write Serial Input and final Auto Program commands are
+ * sent by the caller.
+ */
+
+static int lpc32xx_write_page_hwecc(struct mtd_info *mtd,
+ struct nand_chip *chip, const uint8_t *buf, int oob_required)
+{
+ unsigned int i, status, timeout;
+ struct lpc32xx_oob *oob = (struct lpc32xx_oob *)chip->oob_poi;
+
+ /* when we get here we've already had the SEQIN */
+ for (i = 0; i < 4; i++) {
+ /* start encode (expects 518 writes to buff) */
+ writel(0, &lpc32xx_nand_mlc_registers->ecc_enc_reg);
+ /* copy first 512 bytes from buffer */
+ memcpy(&lpc32xx_nand_mlc_registers->buff, buf+512*i, 512);
+ /* copy next 6 bytes from OOB buffer -- excluding ECC */
+ memcpy(&lpc32xx_nand_mlc_registers->buff, &oob->free[i], 6);
+ /* wait for ECC to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_ECC_READY)
+ break;
+ udelay(1);
+ }
+ /* if ECC stalled, return failure */
+ if (!(status & ISR_ECC_READY))
+ return -1;
+ /* Trigger auto encode (writes 528 bytes to NAND) */
+ writel(0, &lpc32xx_nand_mlc_registers->ecc_auto_enc_reg);
+ /* wait for controller to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_CONTROLLER_READY)
+ break;
+ udelay(1);
+ }
+ /* if controller stalled, return error */
+ if (!(status & ISR_CONTROLLER_READY))
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ * lpc32xx_write_page_raw - write raw (in-band, out-of-band and ECC) data
+ * @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
+ *
+ * Use large block write but without encode.
+ *
+ * The initial Write Serial Input and final Auto Program commands are
+ * sent by the caller.
+ *
+ * This function will write the full out-of-band data, including the
+ * ECC area. Therefore, it can write pages with valid *or* invalid ECC.
+ */
+
+static int lpc32xx_write_page_raw(struct mtd_info *mtd,
+ struct nand_chip *chip, const uint8_t *buf, int oob_required)
+{
+ unsigned int i;
+ struct lpc32xx_oob *oob = (struct lpc32xx_oob *)chip->oob_poi;
+
+ /* when we get here we've already had the Read Mode(1) */
+ for (i = 0; i < 4; i++) {
+ /* copy first 512 bytes from buffer */
+ memcpy(lpc32xx_nand_mlc_registers->buff, buf+512*i, 512);
+ /* copy next 6 bytes into OOB buffer -- excluding ECC */
+ memcpy(lpc32xx_nand_mlc_registers->buff, &oob->free[i], 6);
+ /* copy next 10 bytes into OOB buffer -- that is 'ECC' */
+ memcpy(lpc32xx_nand_mlc_registers->buff, &oob->ecc[i], 10);
+ }
+ return 0;
+}
+
+/**
+ * lpc32xx_write_oob - write out-of-band data
+ * @mtd: mtd info structure
+ * @chip: nand chip info structure
+ * @page: page number to read
+ *
+ * Since ECC covers in- and out-of-band data, writing out-of-band data
+ * with ECC will render the page ECC wrong -- or, if the page was blank,
+ * then it will produce a good ECC but a later in-band data write will
+ * render it wrong.
+ *
+ * Therefore, do not compute or write any ECC, and always return success.
+ *
+ * This implies that we do four writes, since non-ECC out-of-band data
+ * are not contiguous in a large page.
+ */
+
+static int lpc32xx_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
+ int page)
+{
+ /* update oob on all 4 subpages in sequence */
+ unsigned int i, status, timeout;
+ struct lpc32xx_oob *oob = (struct lpc32xx_oob *)chip->oob_poi;
+
+ for (i = 0; i < 4; i++) {
+ /* start data input */
+ chip->cmdfunc(mtd, NAND_CMD_SEQIN, 0x200+0x210*i, page);
+ /* copy 6 non-ECC out-of-band bytes directly into NAND */
+ memcpy(lpc32xx_nand_mlc_registers->data, &oob->free[i], 6);
+ /* program page */
+ chip->cmdfunc(mtd, NAND_CMD_PAGEPROG, -1, -1);
+ /* wait for NAND to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_NAND_READY)
+ break;
+ udelay(1);
+ }
+ /* if NAND stalled, return error */
+ if (!(status & ISR_NAND_READY))
+ return -1;
+ }
+ return 0;
+}
+
+/**
+ * lpc32xx_waitfunc - wait until a command is done
+ * @mtd: MTD device structure
+ * @chip: NAND chip structure
+ *
+ * Wait for controller and FLASH to both be ready.
+ */
+
+static int lpc32xx_waitfunc(struct mtd_info *mtd, struct nand_chip *chip)
+{
+ int status;
+ unsigned int timeout;
+ /* wait until both controller and NAND are ready */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if ((status & (ISR_CONTROLLER_READY || ISR_NAND_READY))
+ == (ISR_CONTROLLER_READY || ISR_NAND_READY))
+ break;
+ udelay(1);
+ }
+ /* if controller or NAND stalled, return error */
+ if ((status & (ISR_CONTROLLER_READY || ISR_NAND_READY))
+ != (ISR_CONTROLLER_READY || ISR_NAND_READY))
+ return -1;
+ /* write NAND status command */
+ writel(NAND_CMD_STATUS, &lpc32xx_nand_mlc_registers->cmd);
+ /* read back status and return it */
+ return readb(&lpc32xx_nand_mlc_registers->data);
+}
+
+/*
+ * We are self-initializing, so we need our own chip struct
+ */
+
+static struct nand_chip lpc32xx_chip;
+
+/*
+ * Initialize the controller
+ */
+
+void board_nand_init(void)
+{
+ /* we have only one device anyway */
+ struct mtd_info *mtd = &nand_info[0];
+ /* chip is struct nand_chip, and is now provided by the driver. */
+ mtd->priv = &lpc32xx_chip;
+ /* to store return status in case we need to print it */
+ int ret;
+
+ /* Set all BOARDSPECIFIC (actually core-specific) fields */
+
+ lpc32xx_chip.IO_ADDR_R = &lpc32xx_nand_mlc_registers->buff;
+ lpc32xx_chip.IO_ADDR_W = &lpc32xx_nand_mlc_registers->buff;
+ lpc32xx_chip.cmd_ctrl = lpc32xx_cmd_ctrl;
+ /* do not set init_size: nand_base.c will read sizes from chip */
+ lpc32xx_chip.dev_ready = lpc32xx_dev_ready;
+ /* do not set setup_read_retry: this is NAND-chip-specific */
+ /* do not set chip_delay: we have dev_ready defined. */
+ lpc32xx_chip.options |= NAND_NO_SUBPAGE_WRITE;
+
+ /* Set needed ECC fields */
+
+ lpc32xx_chip.ecc.mode = NAND_ECC_HW;
+ lpc32xx_chip.ecc.layout = &lpc32xx_largepage_ecclayout;
+ lpc32xx_chip.ecc.size = 512;
+ lpc32xx_chip.ecc.bytes = 10;
+ lpc32xx_chip.ecc.strength = 4;
+ lpc32xx_chip.ecc.read_page = lpc32xx_read_page_hwecc;
+ lpc32xx_chip.ecc.read_page_raw = lpc32xx_read_page_raw;
+ lpc32xx_chip.ecc.write_page = lpc32xx_write_page_hwecc;
+ lpc32xx_chip.ecc.write_page_raw = lpc32xx_write_page_raw;
+ lpc32xx_chip.ecc.read_oob = lpc32xx_read_oob;
+ lpc32xx_chip.ecc.write_oob = lpc32xx_write_oob;
+ lpc32xx_chip.waitfunc = lpc32xx_waitfunc;
+
+ lpc32xx_chip.read_byte = lpc32xx_read_byte; /* FIXME: NEEDED? */
+
+ /* BBT options: read from last two pages */
+ lpc32xx_chip.bbt_options |= NAND_BBT_USE_FLASH | NAND_BBT_LASTBLOCK
+ | NAND_BBT_SCANLASTPAGE | NAND_BBT_SCAN2NDPAGE
+ | NAND_BBT_WRITE;
+
+ /* Initialize NAND interface */
+ lpc32xx_nand_init();
+
+ /* identify chip */
+ ret = nand_scan_ident(mtd, CONFIG_SYS_MAX_NAND_CHIPS, NULL);
+ if (ret) {
+ error("nand_scan_ident returned %i", ret);
+ return;
+ }
+
+ /* finish scanning the chip */
+ ret = nand_scan_tail(mtd);
+ if (ret) {
+ error("nand_scan_tail returned %i", ret);
+ return;
+ }
+
+ /* chip is good, register it */
+ ret = nand_register(0);
+ if (ret)
+ error("nand_register returned %i", ret);
+}
+
+#else /* defined(CONFIG_SPL_BUILD) */
+
+void nand_init(void)
+{
+ /* enable NAND controller */
+ lpc32xx_mlc_nand_init();
+ /* initialize NAND controller */
+ lpc32xx_nand_init();
+}
+
+void nand_deselect(void)
+{
+ /* nothing to do, but SPL requires this function */
+}
+
+static int read_single_page(uint8_t *dest, int page,
+ struct lpc32xx_oob *oob)
+{
+ int status, i, timeout, err, max_bitflips = 0;
+
+ /* enter read mode */
+ writel(NAND_CMD_READ0, &lpc32xx_nand_mlc_registers->cmd);
+ /* send column (lsb then MSB) and page (lsb to MSB) */
+ writel(0, &lpc32xx_nand_mlc_registers->addr);
+ writel(0, &lpc32xx_nand_mlc_registers->addr);
+ writel(page & 0xff, &lpc32xx_nand_mlc_registers->addr);
+ writel((page>>8) & 0xff, &lpc32xx_nand_mlc_registers->addr);
+ writel((page>>16) & 0xff, &lpc32xx_nand_mlc_registers->addr);
+ /* start reading */
+ writel(NAND_CMD_READSTART, &lpc32xx_nand_mlc_registers->cmd);
+
+ /* large page auto decode read */
+ for (i = 0; i < 4; i++) {
+ /* start auto decode (reads 528 NAND bytes) */
+ writel(0, &lpc32xx_nand_mlc_registers->ecc_auto_dec_reg);
+ /* wait for controller to return to ready state */
+ for (timeout = LPC32X_NAND_TIMEOUT; timeout; timeout--) {
+ status = readl(&lpc32xx_nand_mlc_registers->isr);
+ if (status & ISR_CONTROLLER_READY)
+ break;
+ udelay(1);
+ }
+ /* if controller stalled, return error */
+ if (!(status & ISR_CONTROLLER_READY))
+ return -1;
+ /* if decoder failure, return error */
+ if (status & ISR_DECODER_FAILURE)
+ return -1;
+ /* keep count of maximum bitflips performed */
+ if (status & ISR_DECODER_ERROR) {
+ err = ISR_DECODER_ERRORS(status);
+ if (err > max_bitflips)
+ max_bitflips = err;
+ }
+ /* copy first 512 bytes into buffer */
+ memcpy(dest+i*512, lpc32xx_nand_mlc_registers->buff, 512);
+ /* copy next 6 bytes bytes into OOB buffer */
+ memcpy(&oob->free[i], lpc32xx_nand_mlc_registers->buff, 6);
+ }
+ return max_bitflips;
+}
+
+/*
+ * Load U-Boot signed image.
+ * This loads an image from NAND, skipping bad blocks.
+ * A block is declared bad if at least one of its readable pages has
+ * a bad block marker in its OOB at position 0.
+ * If all pages ion a block are unreadable, the block is considered
+ * bad (i.e., assumed not to be part of the image) and skipped.
+ *
+ * IMPORTANT NOTE:
+ *
+ * If the first block of the image is fully unreadable, it will be
+ * ignored and skipped as if it had been marked bad. If it was not
+ * actually marked bad at the time of writing the image, the resulting
+ * image loaded will lack a header and magic number. It could thus be
+ * considered as a raw, headerless, image and SPL might erroneously
+ * jump into it.
+ *
+ * In order to avoid this risk, LPC32XX-based boards which use this
+ * driver MUST define CONFIG_SPL_PANIC_ON_RAW_IMAGE.
+ */
+
+#define BYTES_PER_PAGE 2048
+#define PAGES_PER_BLOCK 64
+#define BYTES_PER_BLOCK (BYTES_PER_PAGE * PAGES_PER_BLOCK)
+#define PAGES_PER_CHIP_MAX 524288
+
+int nand_spl_load_image(uint32_t offs, unsigned int size, void *dst)
+{
+ int bytes_left = size;
+ int pages_left = DIV_ROUND_UP(size, BYTES_PER_PAGE);
+ int blocks_left = DIV_ROUND_UP(size, BYTES_PER_BLOCK);
+ int block = 0;
+ int page = offs / BYTES_PER_PAGE;
+ /* perform reads block by block */
+ while (blocks_left) {
+ /* compute first page number to read */
+ void *block_page_dst = dst;
+ /* read at most one block, possibly less */
+ int block_bytes_left = bytes_left;
+ if (block_bytes_left > BYTES_PER_BLOCK)
+ block_bytes_left = BYTES_PER_BLOCK;
+ /* keep track of good, failed, and "bad" pages */
+ int block_pages_good = 0;
+ int block_pages_bad = 0;
+ int block_pages_err = 0;
+ /* we shall read a full block of pages, maybe less */
+ int block_pages_left = pages_left;
+ if (block_pages_left > PAGES_PER_BLOCK)
+ block_pages_left = PAGES_PER_BLOCK;
+ int block_pages = block_pages_left;
+ int block_page = page;
+ /* while pages are left and the block is not known as bad */
+ while ((block_pages > 0) && (block_pages_bad == 0)) {
+ /* we will read OOB, too, for bad block markers */
+ struct lpc32xx_oob oob;
+ /* read page */
+ int res = read_single_page(block_page_dst, block_page,
+ &oob);
+ /* count readable pages */
+ if (res >= 0) {
+ /* this page is good */
+ block_pages_good++;
+ /* this page is bad */
+ if ((oob.free[0].free_oob_bytes[0] != 0xff)
+ | (oob.free[0].free_oob_bytes[1] != 0xff))
+ block_pages_bad++;
+ } else
+ /* count errors */
+ block_pages_err++;
+ /* we're done with this page */
+ block_page++;
+ block_page_dst += BYTES_PER_PAGE;
+ if (block_pages)
+ block_pages--;
+ }
+ /* a fully unreadable block is considered bad */
+ if (block_pages_good == 0)
+ block_pages_bad = block_pages_err;
+ /* errors are fatal only in good blocks */
+ if ((block_pages_err > 0) && (block_pages_bad == 0))
+ return -1;
+ /* we keep reads only of good blocks */
+ if (block_pages_bad == 0) {
+ dst += block_bytes_left;
+ bytes_left -= block_bytes_left;
+ pages_left -= block_pages_left;
+ blocks_left--;
+ }
+ /* good or bad, we're done with this block */
+ block++;
+ page += PAGES_PER_BLOCK;
+ }
+
+ /* report success */
+ return 0;
+}
+
+#endif /* CONFIG_SPL_BUILD */