/*
* Driver for the built-in NAND controller of the Atheros AR934x SoCs
*
- * Copyright (C) 2011-2012 Gabor Juhos <juhosg@openwrt.org>
+ * Copyright (C) 2011-2013 Gabor Juhos <juhosg@openwrt.org>
*
* 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
#define AR934X_NFC_INT_DEV_RDY(_x) BIT(4 + (_x))
#define AR934X_NFC_INT_CMD_END BIT(1)
+#define AR934X_NFC_ECC_CTRL_ERR_THRES_S 8
+#define AR934X_NFC_ECC_CTRL_ERR_THRES_M 0x1f
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_S 5
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_M 0x7
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_2 0
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_4 1
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_6 2
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_8 3
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_10 4
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_12 5
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_14 6
+#define AR934X_NFC_ECC_CTRL_ECC_CAP_16 7
+#define AR934X_NFC_ECC_CTRL_ERR_OVER BIT(2)
+#define AR934X_NFC_ECC_CTRL_ERR_UNCORRECT BIT(1)
+#define AR934X_NFC_ECC_CTRL_ERR_CORRECT BIT(0)
+
+#define AR934X_NFC_ECC_OFFS_OFSET_M 0xffff
+
/* default timing values */
#define AR934X_NFC_TIME_SEQ_DEFAULT 0x7fff
#define AR934X_NFC_TIMINGS_ASYN_DEFAULT 0x22
u32 irq_status;
u32 ctrl_reg;
+ u32 ecc_ctrl_reg;
+ u32 ecc_offset_reg;
+ u32 ecc_thres;
+ u32 ecc_oob_pos;
+
bool small_page;
unsigned int addr_count0;
unsigned int addr_count1;
static void ar934x_nfc_restart(struct ar934x_nfc *nfc);
+static inline bool
+is_all_ff(u8 *buf, int len)
+{
+ while (len--)
+ if (buf[len] != 0xff)
+ return false;
+
+ return true;
+}
+
static inline void
ar934x_nfc_wr(struct ar934x_nfc *nfc, unsigned reg, u32 val)
{
ar934x_nfc_wr(nfc, AR934X_NFC_REG_DATA_SIZE, len);
ar934x_nfc_wr(nfc, AR934X_NFC_REG_CTRL, ctrl_reg);
ar934x_nfc_wr(nfc, AR934X_NFC_REG_DMA_CTRL, dma_ctrl);
+ ar934x_nfc_wr(nfc, AR934X_NFC_REG_ECC_CTRL, nfc->ecc_ctrl_reg);
+ ar934x_nfc_wr(nfc, AR934X_NFC_REG_ECC_OFFSET, nfc->ecc_offset_reg);
if (ar934x_nfc_use_irq(nfc)) {
ar934x_nfc_wr(nfc, AR934X_NFC_REG_INT_MASK, AR934X_NFC_IRQ_MASK);
int page_addr)
{
struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+ struct nand_chip *nand = mtd->priv;
nfc->read_id = false;
if (command != NAND_CMD_PAGEPROG)
break;
case NAND_CMD_PAGEPROG:
+ if (nand->ecc.mode == NAND_ECC_HW) {
+ /* the data is already written */
+ break;
+ }
+
if (nfc->small_page)
ar934x_nfc_send_cmd(nfc, nfc->seqin_read_cmd);
nfc->buf_index = buf_index;
}
+static inline void
+ar934x_nfc_enable_hwecc(struct ar934x_nfc *nfc)
+{
+ nfc->ctrl_reg |= AR934X_NFC_CTRL_ECC_EN;
+ nfc->ctrl_reg &= ~AR934X_NFC_CTRL_CUSTOM_SIZE_EN;
+}
+
+static inline void
+ar934x_nfc_disable_hwecc(struct ar934x_nfc *nfc)
+{
+ nfc->ctrl_reg &= ~AR934X_NFC_CTRL_ECC_EN;
+ nfc->ctrl_reg |= AR934X_NFC_CTRL_CUSTOM_SIZE_EN;
+}
+
+static int
+ar934x_nfc_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
+ int page)
+{
+ struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+ int err;
+
+ nfc_dbg(nfc, "read_oob: page:%d\n", page);
+
+ err = ar934x_nfc_send_read(nfc, NAND_CMD_READ0, mtd->writesize, page,
+ mtd->oobsize);
+ if (err)
+ return err;
+
+ memcpy(chip->oob_poi, nfc->buf, mtd->oobsize);
+
+ return 0;
+}
+
+static int
+ar934x_nfc_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
+ int page)
+{
+ struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+
+ nfc_dbg(nfc, "write_oob: page:%d\n", page);
+
+ memcpy(nfc->buf, chip->oob_poi, mtd->oobsize);
+
+ return ar934x_nfc_send_write(nfc, NAND_CMD_PAGEPROG, mtd->writesize,
+ page, mtd->oobsize);
+}
+
+static int
+ar934x_nfc_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
+ u8 *buf, int oob_required, int page)
+{
+ struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+ int len;
+ int err;
+
+ nfc_dbg(nfc, "read_page_raw: page:%d oob:%d\n", page, oob_required);
+
+ len = mtd->writesize;
+ if (oob_required)
+ len += mtd->oobsize;
+
+ err = ar934x_nfc_send_read(nfc, NAND_CMD_READ0, 0, page, len);
+ if (err)
+ return err;
+
+ memcpy(buf, nfc->buf, mtd->writesize);
+
+ if (oob_required)
+ memcpy(chip->oob_poi, &nfc->buf[mtd->writesize], mtd->oobsize);
+
+ return 0;
+}
+
+static int
+ar934x_nfc_read_page(struct mtd_info *mtd, struct nand_chip *chip,
+ u8 *buf, int oob_required, int page)
+{
+ struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+ u32 ecc_ctrl;
+ int max_bitflips = 0;
+ bool ecc_failed;
+ bool ecc_corrected;
+ int err;
+
+ nfc_dbg(nfc, "read_page: page:%d oob:%d\n", page, oob_required);
+
+ ar934x_nfc_enable_hwecc(nfc);
+ err = ar934x_nfc_send_read(nfc, NAND_CMD_READ0, 0, page,
+ mtd->writesize);
+ ar934x_nfc_disable_hwecc(nfc);
+
+ if (err)
+ return err;
+
+ /* TODO: optimize to avoid memcpy */
+ memcpy(buf, nfc->buf, mtd->writesize);
+
+ /* read the ECC status */
+ ecc_ctrl = ar934x_nfc_rr(nfc, AR934X_NFC_REG_ECC_CTRL);
+ ecc_failed = ecc_ctrl & AR934X_NFC_ECC_CTRL_ERR_UNCORRECT;
+ ecc_corrected = ecc_ctrl & AR934X_NFC_ECC_CTRL_ERR_CORRECT;
+
+ if (oob_required || ecc_failed) {
+ err = ar934x_nfc_send_read(nfc, NAND_CMD_READ0, mtd->writesize,
+ page, mtd->oobsize);
+ if (err)
+ return err;
+
+ if (oob_required)
+ memcpy(chip->oob_poi, nfc->buf, mtd->oobsize);
+ }
+
+ if (ecc_failed) {
+ /*
+ * The hardware ECC engine reports uncorrectable errors
+ * on empty pages. Check the ECC bytes and the data. If
+ * both contains 0xff bytes only, dont report a failure.
+ *
+ * TODO: prebuild a buffer with 0xff bytes and use memcmp
+ * for better performance?
+ */
+ if (!is_all_ff(&nfc->buf[nfc->ecc_oob_pos], chip->ecc.total) ||
+ !is_all_ff(buf, mtd->writesize))
+ mtd->ecc_stats.failed++;
+ } else if (ecc_corrected) {
+ /*
+ * The hardware does not report the exact count of the
+ * corrected bitflips, use assumptions based on the
+ * threshold.
+ */
+ if (ecc_ctrl & AR934X_NFC_ECC_CTRL_ERR_OVER) {
+ /*
+ * The number of corrected bitflips exceeds the
+ * threshold. Assume the maximum.
+ */
+ max_bitflips = chip->ecc.strength * chip->ecc.steps;
+ } else {
+ max_bitflips = nfc->ecc_thres * chip->ecc.steps;
+ }
+
+ mtd->ecc_stats.corrected += max_bitflips;
+ }
+
+ return max_bitflips;
+}
+
+static int
+ar934x_nfc_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
+ const u8 *buf, int oob_required)
+{
+ struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+ int page;
+ int len;
+
+ page = nfc->seqin_page_addr;
+
+ nfc_dbg(nfc, "write_page_raw: page:%d oob:%d\n", page, oob_required);
+
+ memcpy(nfc->buf, buf, mtd->writesize);
+ len = mtd->writesize;
+
+ if (oob_required) {
+ memcpy(&nfc->buf[mtd->writesize], chip->oob_poi, mtd->oobsize);
+ len += mtd->oobsize;
+ }
+
+ return ar934x_nfc_send_write(nfc, NAND_CMD_PAGEPROG, 0, page, len);
+}
+
+static int
+ar934x_nfc_write_page(struct mtd_info *mtd, struct nand_chip *chip,
+ const u8 *buf, int oob_required)
+{
+ struct ar934x_nfc *nfc = mtd_to_ar934x_nfc(mtd);
+ int page;
+ int err;
+
+ page = nfc->seqin_page_addr;
+
+ nfc_dbg(nfc, "write_page: page:%d oob:%d\n", page, oob_required);
+
+ /* write OOB first */
+ if (oob_required &&
+ !is_all_ff(chip->oob_poi, mtd->oobsize)) {
+ err = ar934x_nfc_write_oob(mtd, chip, page);
+ if (err)
+ return err;
+ }
+
+ /* TODO: optimize to avoid memcopy */
+ memcpy(nfc->buf, buf, mtd->writesize);
+
+ ar934x_nfc_enable_hwecc(nfc);
+ err = ar934x_nfc_send_write(nfc, NAND_CMD_PAGEPROG, 0, page,
+ mtd->writesize);
+ ar934x_nfc_disable_hwecc(nfc);
+
+ return err;
+}
+
static void
ar934x_nfc_hw_init(struct ar934x_nfc *nfc)
{
return err;
}
+static struct nand_ecclayout ar934x_nfc_oob_64_hwecc = {
+ .eccbytes = 28,
+ .eccpos = {
+ 20, 21, 22, 23, 24, 25, 26,
+ 27, 28, 29, 30, 31, 32, 33,
+ 34, 35, 36, 37, 38, 39, 40,
+ 41, 42, 43, 44, 45, 46, 47,
+ },
+ .oobfree = {
+ {
+ .offset = 4,
+ .length = 16,
+ },
+ {
+ .offset = 48,
+ .length = 16,
+ },
+ },
+};
+
+static int
+ar934x_nfc_setup_hwecc(struct ar934x_nfc *nfc)
+{
+ struct nand_chip *nand = &nfc->nand_chip;
+ u32 ecc_cap;
+ u32 ecc_thres;
+
+ if (!config_enabled(CONFIG_MTD_NAND_AR934X_HW_ECC)) {
+ dev_err(nfc->parent, "hardware ECC support is disabled\n");
+ return -EINVAL;
+ }
+
+ switch (nfc->mtd.writesize) {
+ case 2048:
+ nand->ecc.size = 512;
+ nand->ecc.bytes = 7;
+ nand->ecc.strength = 4;
+ nand->ecc.layout = &ar934x_nfc_oob_64_hwecc;
+ break;
+
+ default:
+ dev_err(nfc->parent,
+ "hardware ECC is not available for %d byte pages\n",
+ nfc->mtd.writesize);
+ return -EINVAL;
+ }
+
+ BUG_ON(!nand->ecc.layout);
+
+ switch (nand->ecc.strength) {
+ case 4:
+ ecc_cap = AR934X_NFC_ECC_CTRL_ECC_CAP_4;
+ ecc_thres = 4;
+ break;
+
+ default:
+ dev_err(nfc->parent, "unsupported ECC strength %u\n",
+ nand->ecc.strength);
+ return -EINVAL;
+ }
+
+ nfc->ecc_thres = ecc_thres;
+ nfc->ecc_oob_pos = nand->ecc.layout->eccpos[0];
+
+ nfc->ecc_ctrl_reg = ecc_cap << AR934X_NFC_ECC_CTRL_ECC_CAP_S;
+ nfc->ecc_ctrl_reg |= ecc_thres << AR934X_NFC_ECC_CTRL_ERR_THRES_S;
+
+ nfc->ecc_offset_reg = nfc->mtd.writesize + nfc->ecc_oob_pos;
+
+ nand->ecc.mode = NAND_ECC_HW;
+ nand->ecc.read_page = ar934x_nfc_read_page;
+ nand->ecc.read_page_raw = ar934x_nfc_read_page_raw;
+ nand->ecc.write_page = ar934x_nfc_write_page;
+ nand->ecc.write_page_raw = ar934x_nfc_write_page_raw;
+ nand->ecc.read_oob = ar934x_nfc_read_oob;
+ nand->ecc.write_oob = ar934x_nfc_write_oob;
+
+ return 0;
+}
+
static int
ar934x_nfc_probe(struct platform_device *pdev)
{
mtd->name = dev_name(&pdev->dev);
nand->chip_delay = 25;
- nand->ecc.mode = NAND_ECC_SOFT;
nand->dev_ready = ar934x_nfc_dev_ready;
nand->cmdfunc = ar934x_nfc_cmdfunc;
goto err_free_buf;
}
+ switch (pdata->ecc_mode) {
+ case AR934X_NFC_ECC_SOFT:
+ nand->ecc.mode = NAND_ECC_SOFT;
+ break;
+
+ case AR934X_NFC_ECC_HW:
+ ret = ar934x_nfc_setup_hwecc(nfc);
+ if (ret)
+ goto err_free_buf;
+
+ break;
+
+ default:
+ dev_err(nfc->parent, "unknown ECC mode %d\n", pdata->ecc_mode);
+ return -EINVAL;
+ }
+
ret = nand_scan_tail(mtd);
if (ret) {
dev_err(&pdev->dev, "scan tail failed, err:%d\n", ret);
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