]> www.infradead.org Git - users/willy/linux.git/commitdiff
mtd: rawnand: nuvoton: add new driver for the Nuvoton MA35 SoC
authorHui-Ping Chen <hpchen0nvt@gmail.com>
Fri, 6 Dec 2024 03:13:18 +0000 (03:13 +0000)
committerMiquel Raynal <miquel.raynal@bootlin.com>
Tue, 24 Dec 2024 12:14:22 +0000 (13:14 +0100)
Nuvoton MA35 SoCs NAND Flash Interface Controller
supports 2kiB, 4kiB and 8kiB page size, and up to
8-bit, 12-bit, and 24-bit hardware ECC calculation
circuit to protect data.

Signed-off-by: Hui-Ping Chen <hpchen0nvt@gmail.com>
[Miquel Raynal: Fixed compatible and driver name to match latest bindings]
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
drivers/mtd/nand/raw/Kconfig
drivers/mtd/nand/raw/Makefile
drivers/mtd/nand/raw/nuvoton-ma35d1-nand-controller.c [new file with mode: 0644]

index d0aaccf72d781d804bebd5614011e56cc10013c2..e3677bcaf0350ad8fdb479aec2bc56775b564426 100644 (file)
@@ -454,6 +454,14 @@ config MTD_NAND_TS72XX
        help
          Enables support for NAND controller on ts72xx SBCs.
 
+config MTD_NAND_NUVOTON_MA35
+       tristate "Nuvoton MA35 SoC NAND controller"
+       depends on ARCH_MA35 || COMPILE_TEST
+       depends on OF
+       help
+         Enables support for the NAND controller found on
+         the Nuvoton MA35 series SoCs.
+
 comment "Misc"
 
 config MTD_SM_COMMON
index d0b0e6b83568d10ad8e9c8fff7c20ce02ba351f3..99e79c448847978403a1a71d2e3e8fd0a12cf22f 100644 (file)
@@ -58,6 +58,7 @@ obj-$(CONFIG_MTD_NAND_INTEL_LGM)      += intel-nand-controller.o
 obj-$(CONFIG_MTD_NAND_ROCKCHIP)                += rockchip-nand-controller.o
 obj-$(CONFIG_MTD_NAND_PL35X)           += pl35x-nand-controller.o
 obj-$(CONFIG_MTD_NAND_RENESAS)         += renesas-nand-controller.o
+obj-$(CONFIG_MTD_NAND_NUVOTON_MA35)    += nuvoton-ma35d1-nand-controller.o
 
 nand-objs := nand_base.o nand_legacy.o nand_bbt.o nand_timings.o nand_ids.o
 nand-objs += nand_onfi.o
diff --git a/drivers/mtd/nand/raw/nuvoton-ma35d1-nand-controller.c b/drivers/mtd/nand/raw/nuvoton-ma35d1-nand-controller.c
new file mode 100644 (file)
index 0000000..c23b537
--- /dev/null
@@ -0,0 +1,1029 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2024 Nuvoton Technology Corp.
+ */
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/rawnand.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+/* NFI Registers */
+#define MA35_NFI_REG_DMACTL            0x400
+#define   DMA_EN                               BIT(0)
+#define   DMA_RST                              BIT(1)
+#define   DMA_BUSY                             BIT(9)
+
+#define MA35_NFI_REG_DMASA             0x408
+#define MA35_NFI_REG_GCTL              0x800
+#define   GRST                                 BIT(0)
+#define   NAND_EN                              BIT(3)
+
+#define MA35_NFI_REG_NANDCTL           0x8A0
+#define   SWRST                                BIT(0)
+#define   DMA_R_EN                             BIT(1)
+#define   DMA_W_EN                             BIT(2)
+#define   ECC_CHK                              BIT(7)
+#define   PROT3BEN                             BIT(8)
+#define   PSIZE_2K                             BIT(16)
+#define   PSIZE_4K                             BIT(17)
+#define   PSIZE_8K                             GENMASK(17, 16)
+#define   PSIZE_MASK                           GENMASK(17, 16)
+#define   BCH_T24                              BIT(18)
+#define   BCH_T8                               BIT(20)
+#define   BCH_T12                              BIT(21)
+#define   BCH_NONE                             (0x0)
+#define   BCH_MASK                             GENMASK(22, 18)
+#define   ECC_EN                               BIT(23)
+#define   DISABLE_CS0                          BIT(25)
+
+#define MA35_NFI_REG_NANDINTEN 0x8A8
+#define MA35_NFI_REG_NANDINTSTS        0x8AC
+#define   INT_DMA                              BIT(0)
+#define   INT_ECC                              BIT(2)
+#define   INT_RB0                              BIT(10)
+
+#define MA35_NFI_REG_NANDCMD           0x8B0
+#define MA35_NFI_REG_NANDADDR          0x8B4
+#define   ENDADDR                              BIT(31)
+
+#define MA35_NFI_REG_NANDDATA          0x8B8
+#define MA35_NFI_REG_NANDRACTL 0x8BC
+#define MA35_NFI_REG_NANDECTL          0x8C0
+#define   ENABLE_WP                            0x0
+#define   DISABLE_WP                           BIT(0)
+
+#define MA35_NFI_REG_NANDECCES0        0x8D0
+#define   ECC_STATUS_MASK                      GENMASK(1, 0)
+#define   ECC_ERR_CNT_MASK                     GENMASK(4, 0)
+
+#define MA35_NFI_REG_NANDECCEA0        0x900
+#define MA35_NFI_REG_NANDECCED0        0x960
+#define MA35_NFI_REG_NANDRA0           0xA00
+
+/* Define for the BCH hardware ECC engine */
+/* define the total padding bytes for 512/1024 data segment */
+#define MA35_BCH_PADDING_512   32
+#define MA35_BCH_PADDING_1024  64
+/* define the BCH parity code length for 512 bytes data pattern */
+#define MA35_PARITY_BCH8       15
+#define MA35_PARITY_BCH12      23
+/* define the BCH parity code length for 1024 bytes data pattern */
+#define MA35_PARITY_BCH24      45
+
+#define MA35_MAX_NSELS         (2)
+#define PREFIX_RA_IS_EMPTY(reg)        FIELD_GET(GENMASK(31, 16), (reg))
+
+struct ma35_nand_chip {
+       struct list_head node;
+       struct nand_chip chip;
+
+       u32 eccstatus;
+       u8 nsels;
+       u8 sels[] __counted_by(nsels);
+};
+
+struct ma35_nand_info {
+       struct nand_controller controller;
+       struct device *dev;
+       void __iomem *regs;
+       int irq;
+       struct clk *clk;
+       struct completion complete;
+       struct list_head chips;
+
+       u8 *buffer;
+       unsigned long assigned_cs;
+};
+
+static inline struct ma35_nand_chip *to_ma35_nand(struct nand_chip *chip)
+{
+       return container_of(chip, struct ma35_nand_chip, chip);
+}
+
+static int ma35_ooblayout_ecc(struct mtd_info *mtd, int section,
+                             struct mtd_oob_region *oob_region)
+{
+       struct nand_chip *chip = mtd_to_nand(mtd);
+
+       if (section)
+               return -ERANGE;
+
+       oob_region->length = chip->ecc.total;
+       oob_region->offset = mtd->oobsize - oob_region->length;
+
+       return 0;
+}
+
+static int ma35_ooblayout_free(struct mtd_info *mtd, int section,
+                              struct mtd_oob_region *oob_region)
+{
+       struct nand_chip *chip = mtd_to_nand(mtd);
+
+       if (section)
+               return -ERANGE;
+
+       oob_region->length = mtd->oobsize - chip->ecc.total - 2;
+       oob_region->offset = 2;
+
+       return 0;
+}
+
+static const struct mtd_ooblayout_ops ma35_ooblayout_ops = {
+       .free = ma35_ooblayout_free,
+       .ecc = ma35_ooblayout_ecc,
+};
+
+static inline void ma35_clear_spare(struct nand_chip *chip, int size)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       int i;
+
+       for (i = 0; i < size / 4; i++)
+               writel(0xff, nand->regs + MA35_NFI_REG_NANDRA0);
+}
+
+static inline void read_remaining_bytes(struct ma35_nand_info *nand, u32 *buf,
+                                       u32 offset, int size, int swap)
+{
+       u32 value = readl(nand->regs + MA35_NFI_REG_NANDRA0 + offset);
+       u8 *ptr = (u8 *)buf;
+       int i, shift;
+
+       for (i = 0; i < size; i++) {
+               shift = (swap ? 3 - i : i) * 8;
+               ptr[i] = (value >> shift) & 0xff;
+       }
+}
+
+static inline void ma35_read_spare(struct nand_chip *chip, int size, u32 *buf, u32 offset)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       u32 off = round_down(offset, 4);
+       int len = offset % 4;
+       int i;
+
+       if (len) {
+               read_remaining_bytes(nand, buf, off, 4 - len, 1);
+               off += 4;
+               size -= (4 - len);
+       }
+
+       for (i = 0; i < size / 4; i++)
+               *buf++ = readl(nand->regs + MA35_NFI_REG_NANDRA0 + off + (i * 4));
+
+       read_remaining_bytes(nand, buf, off + (size & ~3), size % 4, 0);
+}
+
+static inline void ma35_write_spare(struct nand_chip *chip, int size, u32 *buf)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       u32 value;
+       int i, j;
+       u8 *ptr;
+
+       for (i = 0, j = 0; i < size / 4; i++, j += 4)
+               writel(*buf++, nand->regs + MA35_NFI_REG_NANDRA0 + j);
+
+       ptr = (u8 *)buf;
+       switch (size % 4) {
+       case 1:
+               writel(*ptr, nand->regs + MA35_NFI_REG_NANDRA0 + j);
+               break;
+       case 2:
+               value = *ptr | (*(ptr + 1) << 8);
+               writel(value, nand->regs + MA35_NFI_REG_NANDRA0 + j);
+               break;
+       case 3:
+               value = *ptr | (*(ptr + 1) << 8) | (*(ptr + 2) << 16);
+               writel(value, nand->regs + MA35_NFI_REG_NANDRA0 + j);
+               break;
+       default:
+               break;
+       }
+}
+
+static void ma35_nand_target_enable(struct nand_chip *chip, unsigned int cs)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       u32 reg;
+
+       switch (cs) {
+       case 0:
+               reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+               writel(reg & ~DISABLE_CS0, nand->regs + MA35_NFI_REG_NANDCTL);
+
+               reg = readl(nand->regs + MA35_NFI_REG_NANDINTSTS);
+               reg |= INT_RB0;
+               writel(reg, nand->regs + MA35_NFI_REG_NANDINTSTS);
+               break;
+       default:
+               break;
+       }
+}
+
+static int ma35_nand_hwecc_init(struct nand_chip *chip, struct ma35_nand_info *nand)
+{
+       struct ma35_nand_chip *nvtnand = to_ma35_nand(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       struct device *dev = mtd->dev.parent;
+       u32 reg;
+
+       nand->buffer = devm_kzalloc(dev, mtd->writesize, GFP_KERNEL);
+       if (!nand->buffer)
+               return -ENOMEM;
+
+       /* Redundant area size */
+       writel(mtd->oobsize, nand->regs + MA35_NFI_REG_NANDRACTL);
+
+       /* Protect redundant 3 bytes and disable ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       reg |= (PROT3BEN | ECC_CHK);
+       reg &= ~ECC_EN;
+
+       if (chip->ecc.strength != 0) {
+               chip->ecc.steps = mtd->writesize / chip->ecc.size;
+               nvtnand->eccstatus = (chip->ecc.steps < 4) ? 1 : chip->ecc.steps / 4;
+               /* Set BCH algorithm */
+               reg &= ~BCH_MASK;
+               switch (chip->ecc.strength) {
+               case 8:
+                       chip->ecc.total = chip->ecc.steps * MA35_PARITY_BCH8;
+                       reg |= BCH_T8;
+                       break;
+               case 12:
+                       chip->ecc.total = chip->ecc.steps * MA35_PARITY_BCH12;
+                       reg |= BCH_T12;
+                       break;
+               case 24:
+                       chip->ecc.total = chip->ecc.steps * MA35_PARITY_BCH24;
+                       reg |= BCH_T24;
+                       break;
+               default:
+                       dev_err(nand->dev, "ECC strength unsupported\n");
+                       return -EINVAL;
+               }
+
+               chip->ecc.bytes = chip->ecc.total / chip->ecc.steps;
+       }
+       writel(reg, nand->regs + MA35_NFI_REG_NANDCTL);
+       return 0;
+}
+
+/* Correct data by BCH alrogithm */
+static void ma35_nfi_correct(struct nand_chip *chip, u8 index,
+                            u8 err_cnt, u8 *addr)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       u32 temp_data[24], temp_addr[24];
+       u32 padding_len, parity_len;
+       u32 value, offset, remain;
+       u32 err_data[6];
+       u8  i, j;
+
+       /* Configurations */
+       if (chip->ecc.strength <= 8) {
+               parity_len = MA35_PARITY_BCH8;
+               padding_len = MA35_BCH_PADDING_512;
+       } else if (chip->ecc.strength <= 12) {
+               parity_len = MA35_PARITY_BCH12;
+               padding_len = MA35_BCH_PADDING_512;
+       } else if (chip->ecc.strength <= 24) {
+               parity_len = MA35_PARITY_BCH24;
+               padding_len = MA35_BCH_PADDING_1024;
+       } else {
+               dev_err(nand->dev, "Invalid BCH_TSEL = 0x%lx\n",
+                       readl(nand->regs + MA35_NFI_REG_NANDCTL) & BCH_MASK);
+               return;
+       }
+
+       /*
+        * got valid BCH_ECC_DATAx and parse them to temp_data[]
+        * got the valid register number of BCH_ECC_DATAx since
+        * one register include 4 error bytes
+        */
+       j = (err_cnt + 3) / 4;
+       j = (j > 6) ? 6 : j;
+       for (i = 0; i < j; i++)
+               err_data[i] = readl(nand->regs + MA35_NFI_REG_NANDECCED0 + i * 4);
+
+       for (i = 0; i < j; i++) {
+               temp_data[i * 4 + 0] = err_data[i] & 0xff;
+               temp_data[i * 4 + 1] = (err_data[i] >> 8) & 0xff;
+               temp_data[i * 4 + 2] = (err_data[i] >> 16) & 0xff;
+               temp_data[i * 4 + 3] = (err_data[i] >> 24) & 0xff;
+       }
+
+       /*
+        * got valid REG_BCH_ECC_ADDRx and parse them to temp_addr[]
+        * got the valid register number of REG_BCH_ECC_ADDRx since
+        * one register include 2 error addresses
+        */
+       j = (err_cnt + 1) / 2;
+       j = (j > 12) ? 12 : j;
+       for (i = 0; i < j; i++) {
+               temp_addr[i * 2 + 0] = readl(nand->regs + MA35_NFI_REG_NANDECCEA0 + i * 4)
+                                       & 0x07ff;
+               temp_addr[i * 2 + 1] = (readl(nand->regs + MA35_NFI_REG_NANDECCEA0 + i * 4)
+                                       >> 16) & 0x07ff;
+       }
+
+       /* pointer to begin address of field that with data error */
+       addr += index * chip->ecc.size;
+
+       /* correct each error bytes */
+       for (i = 0; i < err_cnt; i++) {
+               u32 corrected_index = temp_addr[i];
+
+               if (corrected_index < chip->ecc.size) {
+                       /* for wrong data in field */
+                       *(addr + corrected_index) ^= temp_data[i];
+               } else if (corrected_index < (chip->ecc.size + 3)) {
+                       /* for wrong first-3-bytes in redundancy area */
+                       corrected_index -= chip->ecc.size;
+                       temp_addr[i] += (parity_len * index);   /* field offset */
+
+                       value = readl(nand->regs + MA35_NFI_REG_NANDRA0);
+                       value ^= temp_data[i] << (8 * corrected_index);
+                       writel(value, nand->regs + MA35_NFI_REG_NANDRA0);
+               } else {
+                       /*
+                        * for wrong parity code in redundancy area
+                        * ERR_ADDRx = [data in field] + [3 bytes] + [xx] + [parity code]
+                        *                               |<--     padding bytes      -->|
+                        * The ERR_ADDRx for last parity code always = field size + padding size.
+                        * The first parity code = field size + padding size - parity code length.
+                        * For example, for BCH T12, the first parity code = 512 + 32 - 23 = 521.
+                        * That is, error byte address offset within field is
+                        */
+                       corrected_index -= (chip->ecc.size + padding_len - parity_len);
+
+                       /*
+                        * final address = first parity code of first field +
+                        *                 offset of fields +
+                        *                 offset within field
+                        */
+                       offset = (readl(nand->regs + MA35_NFI_REG_NANDRACTL) & 0x1ff) -
+                               (parity_len * chip->ecc.steps) +
+                               (parity_len * index) + corrected_index;
+
+                       remain = offset % 4;
+                       value = readl(nand->regs + MA35_NFI_REG_NANDRA0 + offset - remain);
+                       value ^= temp_data[i] << (8 * remain);
+                       writel(value, nand->regs + MA35_NFI_REG_NANDRA0 + offset - remain);
+               }
+       }
+}
+
+static int ma35_nfi_ecc_check(struct nand_chip *chip, u8 *addr)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct ma35_nand_chip *nvtnand = to_ma35_nand(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       int maxbitflips = 0;
+       int cnt = 0;
+       u32 status;
+       int i, j;
+
+       for (j = 0; j < nvtnand->eccstatus; j++) {
+               status = readl(nand->regs + MA35_NFI_REG_NANDECCES0 + j * 4);
+               if (!status)
+                       continue;
+
+               for (i = 0; i < 4; i++) {
+                       if ((status & ECC_STATUS_MASK) == 0x01) {
+                               /* Correctable error */
+                               cnt = (status >> 2) & ECC_ERR_CNT_MASK;
+                               ma35_nfi_correct(chip, j * 4 + i, cnt, addr);
+                               maxbitflips = max_t(u32, maxbitflips, cnt);
+                               mtd->ecc_stats.corrected += cnt;
+                       } else {
+                               /* Uncorrectable error */
+                               mtd->ecc_stats.failed++;
+                               dev_err(nand->dev, "uncorrectable error! 0x%4x\n", status);
+                               return -EBADMSG;
+                       }
+                       status >>= 8;
+               }
+       }
+       return maxbitflips;
+}
+
+static void ma35_nand_dmac_init(struct ma35_nand_info *nand)
+{
+       /* DMAC reset and enable */
+       writel(DMA_RST | DMA_EN, nand->regs + MA35_NFI_REG_DMACTL);
+       writel(DMA_EN, nand->regs + MA35_NFI_REG_DMACTL);
+
+       /* Clear DMA finished flag and enable */
+       writel(INT_DMA | INT_ECC, nand->regs + MA35_NFI_REG_NANDINTSTS);
+       writel(INT_DMA, nand->regs + MA35_NFI_REG_NANDINTEN);
+}
+
+static int ma35_nand_do_write(struct nand_chip *chip, const u8 *addr, u32 len)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       dma_addr_t dma_addr;
+       int ret = 0, i;
+       u32 reg;
+
+       if (len != mtd->writesize) {
+               for (i = 0; i < len; i++)
+                       writel(addr[i], nand->regs + MA35_NFI_REG_NANDDATA);
+               return 0;
+       }
+
+       ma35_nand_dmac_init(nand);
+
+       /* To mark this page as dirty. */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDRA0);
+       if (reg & 0xffff0000)
+               writel(reg & 0xffff, nand->regs + MA35_NFI_REG_NANDRA0);
+
+       dma_addr = dma_map_single(nand->dev, (void *)addr, len, DMA_TO_DEVICE);
+       ret = dma_mapping_error(nand->dev, dma_addr);
+       if (ret) {
+               dev_err(nand->dev, "dma mapping error\n");
+               return -EINVAL;
+       }
+       dma_sync_single_for_device(nand->dev, dma_addr, len, DMA_TO_DEVICE);
+
+       reinit_completion(&nand->complete);
+       writel(dma_addr, nand->regs + MA35_NFI_REG_DMASA);
+       writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) | DMA_W_EN,
+              nand->regs + MA35_NFI_REG_NANDCTL);
+       ret = wait_for_completion_timeout(&nand->complete, msecs_to_jiffies(1000));
+       if (!ret) {
+               dev_err(nand->dev, "write timeout\n");
+               ret = -ETIMEDOUT;
+       }
+
+       dma_unmap_single(nand->dev, dma_addr, len, DMA_TO_DEVICE);
+
+       return ret;
+}
+
+static int ma35_nand_do_read(struct nand_chip *chip, u8 *addr, u32 len)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       int ret = 0, cnt = 0, i;
+       dma_addr_t dma_addr;
+       u32 reg;
+
+       if (len != mtd->writesize) {
+               for (i = 0; i < len; i++)
+                       addr[i] = readb(nand->regs + MA35_NFI_REG_NANDDATA);
+               return 0;
+       }
+
+       ma35_nand_dmac_init(nand);
+
+       /* Setup and start DMA using dma_addr */
+       dma_addr = dma_map_single(nand->dev, (void *)addr, len, DMA_FROM_DEVICE);
+       ret = dma_mapping_error(nand->dev, dma_addr);
+       if (ret) {
+               dev_err(nand->dev, "dma mapping error\n");
+               return -EINVAL;
+       }
+
+       reinit_completion(&nand->complete);
+       writel(dma_addr, nand->regs + MA35_NFI_REG_DMASA);
+       writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) | DMA_R_EN,
+              nand->regs + MA35_NFI_REG_NANDCTL);
+       ret = wait_for_completion_timeout(&nand->complete, msecs_to_jiffies(1000));
+       if (!ret) {
+               dev_err(nand->dev, "read timeout\n");
+               ret = -ETIMEDOUT;
+       }
+
+       dma_unmap_single(nand->dev, dma_addr, len, DMA_FROM_DEVICE);
+
+       reg = readl(nand->regs + MA35_NFI_REG_NANDINTSTS);
+       if (reg & INT_ECC) {
+               cnt = ma35_nfi_ecc_check(chip, addr);
+               if (cnt < 0) {
+                       writel(DMA_RST | DMA_EN, nand->regs + MA35_NFI_REG_DMACTL);
+                       writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) | SWRST,
+                              nand->regs + MA35_NFI_REG_NANDCTL);
+               }
+               writel(INT_ECC, nand->regs + MA35_NFI_REG_NANDINTSTS);
+       }
+
+       ret = ret < 0 ? ret : cnt;
+       return ret;
+}
+
+static int ma35_nand_format_subpage(struct nand_chip *chip, u32 offset,
+                                   u32 len, const u8 *buf)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       u32 page_off = round_down(offset, chip->ecc.size);
+       u32 end = DIV_ROUND_UP(page_off + len, chip->ecc.size);
+       u32 start = page_off / chip->ecc.size;
+       u32 reg;
+       int i;
+
+       reg = readl(nand->regs + MA35_NFI_REG_NANDRACTL) | 0xffff0000;
+       memset(nand->buffer, 0xff, mtd->writesize);
+       for (i = start; i < end; i++) {
+               memcpy(nand->buffer + i * chip->ecc.size,
+                      buf + i * chip->ecc.size, chip->ecc.size);
+               reg &= ~(1 << (i + 16));
+       }
+       writel(reg, nand->regs + MA35_NFI_REG_NANDRACTL);
+
+       return 0;
+}
+
+static int ma35_nand_write_subpage_hwecc(struct nand_chip *chip, u32 offset,
+                                        u32 data_len, const u8 *buf,
+                                        int oob_required, int page)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       u32 reg, oobpoi, index;
+       int i;
+
+       /* Enable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg | ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       ma35_nand_target_enable(chip, chip->cur_cs);
+
+       ma35_clear_spare(chip, mtd->oobsize);
+       ma35_write_spare(chip, mtd->oobsize - chip->ecc.total,
+                        (u32 *)chip->oob_poi);
+
+       ma35_nand_format_subpage(chip, offset, data_len, buf);
+       nand_prog_page_begin_op(chip, page, 0, NULL, 0);
+       ma35_nand_do_write(chip, nand->buffer, mtd->writesize);
+       nand_prog_page_end_op(chip);
+
+       oobpoi = mtd->oobsize - chip->ecc.total;
+       reg = readl(nand->regs + MA35_NFI_REG_NANDRACTL);
+       for (i = 0; i < chip->ecc.steps; i++) {
+               index = i * chip->ecc.bytes;
+               if (!(reg & (1 << (i + 16)))) {
+                       ma35_read_spare(chip, chip->ecc.bytes,
+                                       (u32 *)(chip->oob_poi + oobpoi + index),
+                                       oobpoi + index);
+               }
+       }
+
+       writel(mtd->oobsize, nand->regs + MA35_NFI_REG_NANDRACTL);
+       /* Disable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg & ~ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       return 0;
+}
+
+static int ma35_nand_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
+                                     int oob_required, int page)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       u32 reg;
+
+       /* Enable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg | ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       ma35_nand_target_enable(chip, chip->cur_cs);
+
+       ma35_clear_spare(chip, mtd->oobsize);
+       ma35_write_spare(chip, mtd->oobsize - chip->ecc.total,
+                        (u32 *)chip->oob_poi);
+
+       nand_prog_page_begin_op(chip, page, 0, NULL, 0);
+       ma35_nand_do_write(chip, buf, mtd->writesize);
+       nand_prog_page_end_op(chip);
+
+       ma35_read_spare(chip, chip->ecc.total,
+                       (u32 *)(chip->oob_poi + (mtd->oobsize - chip->ecc.total)),
+                       mtd->oobsize - chip->ecc.total);
+
+       /* Disable HW ECC engine */
+       writel(reg & ~ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       return 0;
+}
+
+static int ma35_nand_read_subpage_hwecc(struct nand_chip *chip, u32 offset,
+                                       u32 data_len, u8 *buf, int page)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       int bitflips = 0;
+       u32 reg;
+
+       /* Enable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg | ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       ma35_nand_target_enable(chip, chip->cur_cs);
+       nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
+       ma35_write_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi);
+
+       reg = readl(nand->regs + MA35_NFI_REG_NANDRA0);
+       if (PREFIX_RA_IS_EMPTY(reg)) {
+               memset((void *)buf, 0xff, mtd->writesize);
+       } else {
+               nand_read_page_op(chip, page, offset, NULL, 0);
+               bitflips = ma35_nand_do_read(chip, buf + offset, data_len);
+               ma35_read_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi, 0);
+       }
+
+       /* Disable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg & ~ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       return bitflips;
+}
+
+static int ma35_nand_read_page_hwecc(struct nand_chip *chip, u8 *buf,
+                                    int oob_required, int page)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       int bitflips = 0;
+       u32 reg;
+
+       /* Enable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg | ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       ma35_nand_target_enable(chip, chip->cur_cs);
+       nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
+       ma35_write_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi);
+
+       reg = readl(nand->regs + MA35_NFI_REG_NANDRA0);
+       if (PREFIX_RA_IS_EMPTY(reg)) {
+               memset((void *)buf, 0xff, mtd->writesize);
+       } else {
+               nand_read_page_op(chip, page, 0, NULL, 0);
+               bitflips = ma35_nand_do_read(chip, buf, mtd->writesize);
+               ma35_read_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi, 0);
+       }
+
+       /* Disable HW ECC engine */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       writel(reg & ~ECC_EN, nand->regs + MA35_NFI_REG_NANDCTL);
+
+       return bitflips;
+}
+
+static int ma35_nand_read_oob_hwecc(struct nand_chip *chip, int page)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       u32 reg;
+
+       ma35_nand_target_enable(chip, chip->cur_cs);
+       nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
+
+       /* copy OOB data to controller redundant area for page read */
+       ma35_write_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi);
+
+       reg = readl(nand->regs + MA35_NFI_REG_NANDRA0);
+       if (PREFIX_RA_IS_EMPTY(reg))
+               memset((void *)chip->oob_poi, 0xff, mtd->oobsize);
+
+       return 0;
+}
+
+static inline void ma35_hw_init(struct ma35_nand_info *nand)
+{
+       u32 reg;
+
+       /* Disable flash wp. */
+       writel(DISABLE_WP, nand->regs + MA35_NFI_REG_NANDECTL);
+
+       /* resets the internal state machine and counters */
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL);
+       reg |= SWRST;
+       writel(reg, nand->regs + MA35_NFI_REG_NANDCTL);
+}
+
+static irqreturn_t ma35_nand_irq(int irq, void *id)
+{
+       struct ma35_nand_info *nand = (struct ma35_nand_info *)id;
+       u32 isr;
+
+       isr = readl(nand->regs + MA35_NFI_REG_NANDINTSTS);
+       if (isr & INT_DMA) {
+               writel(INT_DMA, nand->regs + MA35_NFI_REG_NANDINTSTS);
+               complete(&nand->complete);
+               return IRQ_HANDLED;
+       }
+
+       return IRQ_NONE;
+}
+
+static int ma35_nand_attach_chip(struct nand_chip *chip)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       struct mtd_info *mtd = nand_to_mtd(chip);
+       struct device *dev = mtd->dev.parent;
+       u32 reg;
+
+       if (chip->options & NAND_BUSWIDTH_16) {
+               dev_err(dev, "16 bits bus width not supported");
+               return -EINVAL;
+       }
+
+       reg = readl(nand->regs + MA35_NFI_REG_NANDCTL) & (~PSIZE_MASK);
+       switch (mtd->writesize) {
+       case SZ_2K:
+               writel(reg | PSIZE_2K, nand->regs + MA35_NFI_REG_NANDCTL);
+               break;
+       case SZ_4K:
+               writel(reg | PSIZE_4K, nand->regs + MA35_NFI_REG_NANDCTL);
+               break;
+       case SZ_8K:
+               writel(reg | PSIZE_8K, nand->regs + MA35_NFI_REG_NANDCTL);
+               break;
+       default:
+               dev_err(dev, "Unsupported page size");
+               return -EINVAL;
+       }
+
+       switch (chip->ecc.engine_type) {
+       case NAND_ECC_ENGINE_TYPE_ON_HOST:
+               /* Do not store BBT bits in the OOB section as it is not protected */
+               if (chip->bbt_options & NAND_BBT_USE_FLASH)
+                       chip->bbt_options |= NAND_BBT_NO_OOB;
+               chip->options |= NAND_USES_DMA | NAND_SUBPAGE_READ;
+               chip->ecc.write_subpage = ma35_nand_write_subpage_hwecc;
+               chip->ecc.write_page = ma35_nand_write_page_hwecc;
+               chip->ecc.read_subpage = ma35_nand_read_subpage_hwecc;
+               chip->ecc.read_page  = ma35_nand_read_page_hwecc;
+               chip->ecc.read_oob   = ma35_nand_read_oob_hwecc;
+               return ma35_nand_hwecc_init(chip, nand);
+       case NAND_ECC_ENGINE_TYPE_NONE:
+       case NAND_ECC_ENGINE_TYPE_SOFT:
+       case NAND_ECC_ENGINE_TYPE_ON_DIE:
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+static int ma35_nfc_exec_instr(struct nand_chip *chip,
+                              const struct nand_op_instr *instr)
+{
+       struct ma35_nand_info *nand = nand_get_controller_data(chip);
+       unsigned int i;
+       int ret = 0;
+       u32 status;
+
+       switch (instr->type) {
+       case NAND_OP_CMD_INSTR:
+               writel(instr->ctx.cmd.opcode, nand->regs + MA35_NFI_REG_NANDCMD);
+               break;
+       case NAND_OP_ADDR_INSTR:
+               for (i = 0; i < instr->ctx.addr.naddrs; i++) {
+                       if (i == (instr->ctx.addr.naddrs - 1))
+                               writel(instr->ctx.addr.addrs[i] | ENDADDR,
+                                      nand->regs + MA35_NFI_REG_NANDADDR);
+                       else
+                               writel(instr->ctx.addr.addrs[i],
+                                      nand->regs + MA35_NFI_REG_NANDADDR);
+               }
+               break;
+       case NAND_OP_DATA_IN_INSTR:
+               ret = ma35_nand_do_read(chip, instr->ctx.data.buf.in, instr->ctx.data.len);
+               break;
+       case NAND_OP_DATA_OUT_INSTR:
+               ret = ma35_nand_do_write(chip, instr->ctx.data.buf.out, instr->ctx.data.len);
+               break;
+       case NAND_OP_WAITRDY_INSTR:
+               return readl_poll_timeout(nand->regs + MA35_NFI_REG_NANDINTSTS, status,
+                                         status & INT_RB0, 20,
+                                         instr->ctx.waitrdy.timeout_ms * MSEC_PER_SEC);
+       default:
+               ret = -EINVAL;
+               break;
+       }
+
+       return ret;
+}
+
+static int ma35_nfc_exec_op(struct nand_chip *chip,
+                           const struct nand_operation *op,
+                           bool check_only)
+{
+       int ret = 0;
+       u32 i;
+
+       if (check_only)
+               return 0;
+
+       ma35_nand_target_enable(chip, op->cs);
+
+       for (i = 0; i < op->ninstrs; i++) {
+               ret = ma35_nfc_exec_instr(chip, &op->instrs[i]);
+               if (ret)
+                       break;
+       }
+
+       return ret;
+}
+
+static const struct nand_controller_ops ma35_nfc_ops = {
+       .attach_chip = ma35_nand_attach_chip,
+       .exec_op = ma35_nfc_exec_op,
+};
+
+static int ma35_nand_chip_init(struct device *dev, struct ma35_nand_info *nand,
+                              struct device_node *np)
+{
+       struct ma35_nand_chip *nvtnand;
+       struct nand_chip *chip;
+       struct mtd_info *mtd;
+       int nsels;
+       int ret;
+       u32 cs;
+       int i;
+
+       nsels = of_property_count_elems_of_size(np, "reg", sizeof(u32));
+       if (!nsels || nsels > MA35_MAX_NSELS) {
+               dev_err(dev, "invalid reg property size %d\n", nsels);
+               return -EINVAL;
+       }
+
+       nvtnand = devm_kzalloc(dev, struct_size(nvtnand, sels, nsels),
+                              GFP_KERNEL);
+       if (!nvtnand)
+               return -ENOMEM;
+
+       nvtnand->nsels = nsels;
+       for (i = 0; i < nsels; i++) {
+               ret = of_property_read_u32_index(np, "reg", i, &cs);
+               if (ret) {
+                       dev_err(dev, "reg property failure : %d\n", ret);
+                       return ret;
+               }
+
+               if (cs >= MA35_MAX_NSELS) {
+                       dev_err(dev, "invalid CS: %u\n", cs);
+                       return -EINVAL;
+               }
+
+               if (test_and_set_bit(cs, &nand->assigned_cs)) {
+                       dev_err(dev, "CS %u already assigned\n", cs);
+                       return -EINVAL;
+               }
+
+               nvtnand->sels[i] = cs;
+       }
+
+       chip = &nvtnand->chip;
+       chip->controller = &nand->controller;
+
+       nand_set_flash_node(chip, np);
+       nand_set_controller_data(chip, nand);
+
+       mtd = nand_to_mtd(chip);
+       mtd->owner = THIS_MODULE;
+       mtd->dev.parent = dev;
+
+       mtd_set_ooblayout(mtd, &ma35_ooblayout_ops);
+       ret = nand_scan(chip, nsels);
+       if (ret)
+               return ret;
+
+       ret = mtd_device_register(mtd, NULL, 0);
+       if (ret) {
+               nand_cleanup(chip);
+               return ret;
+       }
+
+       list_add_tail(&nvtnand->node, &nand->chips);
+
+       return 0;
+}
+
+static void ma35_chips_cleanup(struct ma35_nand_info *nand)
+{
+       struct ma35_nand_chip *nvtnand, *tmp;
+       struct nand_chip *chip;
+       int ret;
+
+       list_for_each_entry_safe(nvtnand, tmp, &nand->chips, node) {
+               chip = &nvtnand->chip;
+               ret = mtd_device_unregister(nand_to_mtd(chip));
+               WARN_ON(ret);
+               nand_cleanup(chip);
+               list_del(&nvtnand->node);
+       }
+}
+
+static int ma35_nand_chips_init(struct device *dev, struct ma35_nand_info *nand)
+{
+       struct device_node *np = dev->of_node, *nand_np;
+       int ret;
+
+       for_each_child_of_node(np, nand_np) {
+               ret = ma35_nand_chip_init(dev, nand, nand_np);
+               if (ret) {
+                       ma35_chips_cleanup(nand);
+                       return ret;
+               }
+       }
+       return 0;
+}
+
+static int ma35_nand_probe(struct platform_device *pdev)
+{
+       struct ma35_nand_info *nand;
+       int ret = 0;
+
+       nand = devm_kzalloc(&pdev->dev, sizeof(*nand), GFP_KERNEL);
+       if (!nand)
+               return -ENOMEM;
+
+       nand_controller_init(&nand->controller);
+       INIT_LIST_HEAD(&nand->chips);
+       nand->controller.ops = &ma35_nfc_ops;
+
+       init_completion(&nand->complete);
+
+       nand->regs = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(nand->regs))
+               return PTR_ERR(nand->regs);
+
+       nand->dev = &pdev->dev;
+
+       nand->clk = devm_clk_get_enabled(&pdev->dev, "nand_gate");
+       if (IS_ERR(nand->clk))
+               return dev_err_probe(&pdev->dev, PTR_ERR(nand->clk),
+                                    "failed to find NAND clock\n");
+
+       nand->irq = platform_get_irq(pdev, 0);
+       if (nand->irq < 0)
+               return dev_err_probe(&pdev->dev, nand->irq,
+                                    "failed to get platform irq\n");
+
+       ret = devm_request_irq(&pdev->dev, nand->irq, ma35_nand_irq,
+                              IRQF_TRIGGER_HIGH, "ma35d1-nand-controller", nand);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to request NAND irq\n");
+               return -ENXIO;
+       }
+
+       platform_set_drvdata(pdev, nand);
+
+       writel(GRST | NAND_EN, nand->regs + MA35_NFI_REG_GCTL);
+       ma35_hw_init(nand);
+       ret = ma35_nand_chips_init(&pdev->dev, nand);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to init NAND chips\n");
+               clk_disable(nand->clk);
+               return ret;
+       }
+
+       return ret;
+}
+
+static void ma35_nand_remove(struct platform_device *pdev)
+{
+       struct ma35_nand_info *nand = platform_get_drvdata(pdev);
+
+       ma35_chips_cleanup(nand);
+}
+
+static const struct of_device_id ma35_nand_of_match[] = {
+       { .compatible = "nuvoton,ma35d1-nand-controller" },
+       {},
+};
+MODULE_DEVICE_TABLE(of, ma35_nand_of_match);
+
+static struct platform_driver ma35_nand_driver = {
+       .driver = {
+               .name = "ma35d1-nand-controller",
+               .of_match_table = ma35_nand_of_match,
+       },
+       .probe = ma35_nand_probe,
+       .remove = ma35_nand_remove,
+};
+
+module_platform_driver(ma35_nand_driver);
+
+MODULE_DESCRIPTION("Nuvoton ma35 NAND driver");
+MODULE_AUTHOR("Hui-Ping Chen <hpchen0nvt@gmail.com>");
+MODULE_LICENSE("GPL");