Hi Hui-Ping, hpchen0nvt@xxxxxxxxx wrote on Fri, 27 Sep 2024 02:07:49 +0000: > 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@xxxxxxxxx> > --- > drivers/mtd/nand/raw/Kconfig | 8 + > drivers/mtd/nand/raw/Makefile | 1 + > drivers/mtd/nand/raw/nuvoton_ma35d1_nand.c | 862 +++++++++++++++++++++ > 3 files changed, 871 insertions(+) > create mode 100644 drivers/mtd/nand/raw/nuvoton_ma35d1_nand.c > > diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig > index d0aaccf72d78..e3677bcaf035 100644 > --- a/drivers/mtd/nand/raw/Kconfig > +++ b/drivers/mtd/nand/raw/Kconfig > @@ -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 > diff --git a/drivers/mtd/nand/raw/Makefile b/drivers/mtd/nand/raw/Makefile > index d0b0e6b83568..cc24955627f8 100644 > --- a/drivers/mtd/nand/raw/Makefile > +++ b/drivers/mtd/nand/raw/Makefile > @@ -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.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.c b/drivers/mtd/nand/raw/nuvoton_ma35d1_nand.c > new file mode 100644 > index 000000000000..efd60493f22a > --- /dev/null > +++ b/drivers/mtd/nand/raw/nuvoton_ma35d1_nand.c > @@ -0,0 +1,862 @@ > +// 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 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 INT_RB0_STS BIT(18) > + > +#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 > + > +struct ma35_nand_info { > + struct nand_controller controller; > + struct nand_chip chip; > + struct device *dev; > + void __iomem *regs; > + int irq; > + struct clk *clk; > + struct completion complete; > + u32 bch; > + u32 bitflips; > + u8 *ecc_buf; > +}; > + > +static int ma35_ooblayout_ecc(struct mtd_info *mtd, int section, > + struct mtd_oob_region *oobregion) > +{ > + struct nand_chip *chip = mtd_to_nand(mtd); > + > + if (section) > + return -ERANGE; > + > + oobregion->length = chip->ecc.total; > + oobregion->offset = mtd->oobsize - oobregion->length; > + > + return 0; > +} > + > +static int ma35_ooblayout_free(struct mtd_info *mtd, int section, > + struct mtd_oob_region *oobregion) > +{ > + struct nand_chip *chip = mtd_to_nand(mtd); > + > + if (section) > + return -ERANGE; > + > + oobregion->length = mtd->oobsize - chip->ecc.total - 2; > + oobregion->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++) Spacing ^ > + 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) > +{ > + u32 value = readl(nand->regs + MA35_NFI_REG_NANDRA0 + offset); > + u8 *ptr = (u8 *)buf; > + int i; > + > + for (i = 0; i < size; i++) > + ptr[i] = (value >> (i * 8)) & 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); > + int i, j; > + > + if ((offset % 4) == 0) { > + for (i = 0, j = 0; i < size / 4; i++, j += 4) > + *buf++ = readl(nand->regs + MA35_NFI_REG_NANDRA0 + offset + j); > + > + read_remaining_bytes(nand, buf, offset + j, size % 4); > + } else { > + read_remaining_bytes(nand, buf, offset, 4 - (offset % 4)); > + offset += 4; > + size -= (4 - (offset % 4)); > + > + for (i = 0, j = 0; i < size / 4; i++, j += 4) > + *buf++ = readl(nand->regs + MA35_NFI_REG_NANDRA0 + offset + j); > + > + read_remaining_bytes(nand, buf, offset + j, size % 4); > + } > +} > + > +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 inline void ma35_nand_target_enable(struct ma35_nand_info *nand) > +{ > + writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) & (~DISABLE_CS0), > + nand->regs+MA35_NFI_REG_NANDCTL); > +} > + > +static inline void ma35_nand_target_disable(struct ma35_nand_info *nand) > +{ > + writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) | DISABLE_CS0, > + nand->regs + MA35_NFI_REG_NANDCTL); > +} > + > +static void ma35_nand_hwecc_init(struct ma35_nand_info *nand) > +{ > + struct mtd_info *mtd = nand_to_mtd(&nand->chip); > + u32 reg; > + > + /* resets the internal state machine and counters Please check the style in all you comments. /* * Reset the > + * This bit will be auto cleared after a few clock cycles. > + */ > + reg = readl(nand->regs + MA35_NFI_REG_NANDCTL); > + reg |= SWRST; > + writel(reg, nand->regs + MA35_NFI_REG_NANDCTL); This has a way wider impact than just configuring the hw ECC engine, no? Are you sure you want to do this now? I believe it should be in its own helper, and you want to do it earlier than that, like before the discovery step (and also in the resume path). > + while (readl(nand->regs + MA35_NFI_REG_NANDCTL) & SWRST) > + ; cpu_relax() > + > + /* Redundant area size */ > + writel(mtd->oobsize, nand->regs + MA35_NFI_REG_NANDRACTL); > + > + /* Protect redundant 3 bytes */ > + reg = readl(nand->regs + MA35_NFI_REG_NANDCTL); > + reg |= (PROT3BEN | ECC_CHK); > + writel(reg, nand->regs + MA35_NFI_REG_NANDCTL); > + > + if (nand->bch == BCH_NONE) { Please use the definitions/constants from the core. > + /* Disable H/W ECC, ECC parity check enable bit during read page */ > + writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) & (~ECC_EN), > + nand->regs + MA35_NFI_REG_NANDCTL); Move the readl before the if and save it in the reg variable. In general please do not overload the lines like that when it's not needed. > + } else { > + /* Set BCH algorithm */ > + writel((readl(nand->regs + MA35_NFI_REG_NANDCTL) & (~BCH_MASK)) | Parenthesis are not needed ^ > + nand->bch, nand->regs + MA35_NFI_REG_NANDCTL); > + > + /* Enable H/W ECC, ECC parity check enable bit during read page */ > + writel(readl(nand->regs + MA35_NFI_REG_NANDCTL) | ECC_EN, > + nand->regs + MA35_NFI_REG_NANDCTL); > + } > +} > + > +/* Correct data by BCH alrogithm */ > +static void ma35_nfi_correct(struct ma35_nand_info *nand, u8 index, > + u8 err_cnt, u8 *addr) > +{ > + u32 temp_data[24], temp_addr[24]; > + u32 padding_len, parity_len; > + u32 value, offset, remain; > + u32 err_data[6]; > + u8 i, j; > + > + /* configurations */ > + switch (nand->bch) { > + case BCH_T24: > + parity_len = MA35_PARITY_BCH24; > + padding_len = MA35_BCH_PADDING_1024; > + break; > + case BCH_T12: > + parity_len = MA35_PARITY_BCH12; > + padding_len = MA35_BCH_PADDING_512; > + break; > + case BCH_T8: > + parity_len = MA35_PARITY_BCH8; > + padding_len = MA35_BCH_PADDING_512; > + break; > + default: > + dev_warn(nand->dev, "NAND ERROR: invalid SMCR_BCH_TSEL = 0x%08X\n", > + (u32)(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 * nand->chip.ecc.steps; > + > + /* correct each error bytes */ > + for (i = 0; i < err_cnt; i++) { > + u32 corrected_index = temp_addr[i]; > + > + /* for wrong data in field */ > + if (corrected_index < nand->chip.ecc.steps) > + *(addr + corrected_index) ^= temp_data[i]; > + > + /* for wrong first-3-bytes in redundancy area */ > + else if (corrected_index < (nand->chip.ecc.steps + 3)) { > + corrected_index -= nand->chip.ecc.steps; > + 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); > + } > + /* for wrong parity code in redundancy area > + * BCH_ERR_ADDRx = [data in field] + [3 bytes] + [xx] + [parity code] > + * |<-- padding bytes -->| > + * The BCH_ERR_ADDRx for last parity code always = field size + padding size. > + * So, 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 > + */ > + else { > + corrected_index -= (nand->chip.ecc.steps + 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 * nand->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 mtd_info *mtd = nand_to_mtd(chip); > + int i, j, nchunks = 0; > + int report_err = 0; > + int err_cnt = 0; > + u32 status; > + > + nchunks = mtd->writesize / chip->ecc.steps; > + if (nchunks < 4) > + nchunks = 1; > + else > + nchunks /= 4; > + > + for (j = 0; j < nchunks; 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)) { > + /* No error */ > + status >>= 8; > + continue; Remove this block, it will do the same and be more clear. > + } else if ((status & ECC_STATUS_MASK) == 0x01) { > + /* Correctable error */ > + err_cnt = (status >> 2) & ECC_ERR_CNT_MASK; > + ma35_nfi_correct(nand, j*4+i, err_cnt, addr); Spacing ^^^^^^ > + report_err += err_cnt; > + } else { > + /* uncorrectable error */ > + dev_warn(nand->dev, "uncorrectable error! 0x%4x\n", status); > + return -1; Not a valid error code > + } > + status >>= 8; > + } > + } > + return report_err; > +} > + > +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 */ > + writel(INT_DMA | INT_ECC, nand->regs + MA35_NFI_REG_NANDINTSTS); > + > + init_completion(&nand->complete); You're gonna call init_completion more than once during suspend/resume cycles, this is unsafe. > +} > + > +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); > + > + writel(mtd->oobsize, nand->regs + MA35_NFI_REG_NANDRACTL); > + > + writel(INT_DMA, nand->regs + MA35_NFI_REG_NANDINTEN); > + /* 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); > + > + writel((unsigned long)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) = (u8)readl(nand->regs + MA35_NFI_REG_NANDDATA); Mmh, that line is strange. Please don't do that. addr[i] = readb() ? > + return 0; > + } > + > + ma35_nand_dmac_init(nand); > + > + writel(mtd->oobsize, nand->regs + MA35_NFI_REG_NANDRACTL); > + > + /* 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; > + } > + > + writel((unsigned long)dma_addr, nand->regs + MA35_NFI_REG_DMASA); Please enforce a dma mask of 32 (even though it might be the fault). > + 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(&nand->chip, addr); > + if (cnt < 0) { > + mtd->ecc_stats.failed++; > + 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); > + } else { > + mtd->ecc_stats.corrected += cnt; > + nand->bitflips = cnt; > + } > + writel(INT_ECC, nand->regs + MA35_NFI_REG_NANDINTSTS); > + } > + > + return ret; > +} > + > +static int ma35_nand_write_page_hwecc(struct nand_chip *chip, const u8 *buf, > + int oob_required, int page) > +{ > + struct mtd_info *mtd = nand_to_mtd(chip); > + void *ecc_calc = chip->ecc.calc_buf; > + > + 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, buf, mtd->writesize); > + nand_prog_page_end_op(chip); > + > + /* Copy parity code in NANDRA to calc */ > + ma35_read_spare(chip, chip->ecc.total, (u32 *)ecc_calc, > + mtd->oobsize - chip->ecc.total); > + > + /* Copy parity code in calc to oob_poi */ > + memcpy(chip->oob_poi + (mtd->oobsize - chip->ecc.total), > + ecc_calc, chip->ecc.total); > + > + return 0; > +} > + > +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); > + u32 reg; > + > + /* read the OOB area */ > + nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize); > + nand->bitflips = 0; Why storing this value in your structure? > + > + /* copy OOB data to NANDRA for page read */ > + ma35_write_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi); > + > + reg = readl(nand->regs + MA35_NFI_REG_NANDRA0); > + if (reg & 0xffff0000) { > + memset((void *)buf, 0xff, mtd->writesize); > + } else { > + /* read data from nand */ > + nand_read_page_op(chip, page, 0, buf, mtd->writesize); ret = if (ret) ... > + > + /* restore OOB data from SMRA */ > + ma35_read_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi, 0); same > + } > + > + return nand->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; > + > + nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize); > + > + /* copy OOB data to NANDRA for page read */ What is NANDRA? does not mean anything to me. > + ma35_write_spare(chip, mtd->oobsize, (u32 *)chip->oob_poi); > + > + reg = readl(nand->regs + MA35_NFI_REG_NANDRA0); > + if (reg & 0xffff0000) > + memset((void *)chip->oob_poi, 0xff, mtd->oobsize); What does this mean? > + > + return 0; > +} > + > +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); > + } I guess a more future proof implementation would always writel(isr); to silence the interrupt. Otherwise of course you must call complete() only upon isr & INT_DMA. > + > + return IRQ_HANDLED; > +} > + > +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); > + unsigned int reg; > + > + if (chip->options & NAND_BUSWIDTH_16) { > + dev_err(nand->dev, "16 bits bus width not supported"); > + return -EINVAL; > + } > + > + /* support only ecc hw mode */ Why ? Please don't. > + if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST) { > + dev_err(nand->dev, "ecc.engine_type not supported\n"); > + return -EINVAL; > + } > + > + nand->ecc_buf = devm_kzalloc(nand->dev, mtd->writesize + mtd->oobsize, > + GFP_KERNEL); > + if (!nand->ecc_buf) > + return -ENOMEM; > + chip->ecc.calc_buf = nand->ecc_buf; Are you sure you need this? I don't see the point. > + > + /* Set PSize */ > + reg = readl(nand->regs + MA35_NFI_REG_NANDCTL) & (~PSIZE_MASK); > + if (mtd->writesize == 2048) > + writel(reg | PSIZE_2K, nand->regs + MA35_NFI_REG_NANDCTL); > + else if (mtd->writesize == 4096) > + writel(reg | PSIZE_4K, nand->regs + MA35_NFI_REG_NANDCTL); > + else if (mtd->writesize == 8192) > + writel(reg | PSIZE_8K, nand->regs + MA35_NFI_REG_NANDCTL); > + > + chip->ecc.steps = mtd->writesize / chip->ecc.size; > + if (chip->ecc.strength == 0) { > + nand->bch = BCH_NONE; /* No ECC */ > + chip->ecc.total = 0; > + } else if (chip->ecc.strength <= 8) { > + nand->bch = BCH_T8; /* T8 */ bch is probably a bad name, and in general I don't see the point of saving this value. Just check the ECC strength in the above switch cases and don't use this intermediate variable. > + chip->ecc.total = chip->ecc.steps * MA35_PARITY_BCH8; > + } else if (chip->ecc.strength <= 12) { > + nand->bch = BCH_T12; /* T12 */ > + chip->ecc.total = chip->ecc.steps * MA35_PARITY_BCH12; > + } else if (chip->ecc.strength <= 24) { > + nand->bch = BCH_T24; /* T24 */ > + chip->ecc.total = chip->ecc.steps * MA35_PARITY_BCH24; > + } else { > + dev_warn(nand->dev, "NAND Controller is not support this flash. (%d, %d)\n", > + mtd->writesize, mtd->oobsize); This must be a dev_err() and return an error immediately. Also the string is not correct. > + } > + > + chip->ecc.bytes = chip->ecc.total / chip->ecc.steps; > + mtd_set_ooblayout(mtd, &ma35_ooblayout_ops); > + > + /* add mtd-id. The string should same as uboot definition */ > + mtd->name = "nand0"; No! There are DT labels for that and mtd->name will automatically be set when calling nand_set_flash_node(). > + > + ma35_nand_hwecc_init(nand); > + > + writel(DISABLE_WP, nand->regs + MA35_NFI_REG_NANDECTL); > + > + 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; > + u32 status; > + > + switch (instr->type) { > + case NAND_OP_CMD_INSTR: > + writel(instr->ctx.cmd.opcode, nand->regs + MA35_NFI_REG_NANDCMD); > + return 0; > + 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); > + } > + return 0; > + case NAND_OP_DATA_IN_INSTR: > + ma35_nand_do_read(chip, instr->ctx.data.buf.in, instr->ctx.data.len); > + return 0; > + case NAND_OP_DATA_OUT_INSTR: > + ma35_nand_do_write(chip, instr->ctx.data.buf.out, instr->ctx.data.len); > + return 0; > + 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 * 1000); MSEC_PER_SEC > + default: > + break; > + } > + > + return -EINVAL; > +} This is much better than the legacy hooks! > + > +static int ma35_nfc_exec_op(struct nand_chip *chip, > + const struct nand_operation *op, > + bool check_only) > +{ > + struct ma35_nand_info *nand = nand_get_controller_data(chip); > + int ret = 0; > + u32 i, reg; > + > + if (check_only) > + return 0; > + > + ma35_nand_target_enable(nand); > + > + reg = readl(nand->regs + MA35_NFI_REG_NANDINTSTS); > + reg |= INT_RB0; This RB pin looks like something hardcoded, whereas it should not :-) If you have several RB, it means you have several CS as well! > + writel(reg, nand->regs + MA35_NFI_REG_NANDINTSTS); > + > + for (i = 0; i < op->ninstrs; i++) { > + ret = ma35_nfc_exec_instr(chip, &op->instrs[i]); > + if (ret) > + break; > + } > + > + ma35_nand_target_disable(nand); > + > + 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_probe(struct platform_device *pdev) > +{ > + struct ma35_nand_info *nand; > + struct nand_chip *chip; > + struct mtd_info *mtd; > + int ret = 0; > + > + nand = devm_kzalloc(&pdev->dev, sizeof(*nand), GFP_KERNEL); > + if (!nand) > + return -ENOMEM; > + > + nand_controller_init(&nand->controller); > + nand->controller.ops = &ma35_nfc_ops; > + > + nand->regs = devm_platform_ioremap_resource(pdev, 0); > + if (IS_ERR(nand->regs)) > + return PTR_ERR(nand->regs); > + > + nand->dev = &pdev->dev; > + chip = &nand->chip; > + nand_set_controller_data(chip, nand); > + nand_set_flash_node(chip, pdev->dev.of_node); > + > + 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 > + > + 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", nand); > + if (ret) { > + dev_err(&pdev->dev, "failed to request NAND irq\n"); > + return -ENXIO; > + } > + > + nand->chip.controller = &nand->controller; > + platform_set_drvdata(pdev, nand); > + > + chip->options |= NAND_NO_SUBPAGE_WRITE | NAND_USES_DMA; > + > + chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST; > + chip->ecc.write_page = ma35_nand_write_page_hwecc; > + chip->ecc.read_page = ma35_nand_read_page_hwecc; > + chip->ecc.read_oob = ma35_nand_read_oob_hwecc; You support to disable the ECC engine, so you must support software corrections as well. Please don't force hw ECC use. Please look at other implementations, there is usually a helper with a switch case which supports various ECC configurations. > + > + mtd = nand_to_mtd(chip); > + mtd->priv = chip; > + mtd->owner = THIS_MODULE; > + mtd->dev.parent = &pdev->dev; > + > + writel(NAND_EN, nand->regs + MA35_NFI_REG_GCTL); I would expect your reset bit to be set before this writel. > + > + ret = nand_scan(chip, 1); > + if (ret) > + return ret; > + > + ret = mtd_device_register(mtd, NULL, 0); > + if (ret) { > + nand_cleanup(chip); > + return ret; > + } > + > + return ret; return 0; then > +} > + > +static void ma35_nand_remove(struct platform_device *pdev) > +{ > + struct ma35_nand_info *nand = platform_get_drvdata(pdev); > + int ret; > + > + ret = mtd_device_unregister(nand_to_mtd(&nand->chip)); > + WARN_ON(ret); > + nand_cleanup(&nand->chip); > +} > + > +/* PM Support */ > +#ifdef CONFIG_PM > +static int ma35_nand_suspend(struct platform_device *pdev, pm_message_t pm) > +{ > + struct ma35_nand_info *nand = platform_get_drvdata(pdev); > + int ret = 0; > + u32 val; > + > + /* wait DMAC to ready */ be > + ret = readl_poll_timeout(nand->regs + MA35_NFI_REG_DMACTL, val, > + !(val & DMA_BUSY), 50, HZ/2); > + if (ret) > + dev_warn(&pdev->dev, "dma busy\n"); DMA And please make a sentence. > + > + clk_disable(nand->clk); If you decide to return ret != 0, shall you really disable this clock ? > + > + return ret; > +} > + > +static int ma35_nand_resume(struct platform_device *pdev) > +{ > + struct ma35_nand_info *nand = platform_get_drvdata(pdev); > + > + clk_enable(nand->clk); > + ma35_nand_hwecc_init(nand); The naming is wrong. This init is not just the hw ECC controller. > + ma35_nand_dmac_init(nand); > + > + return 0; > +} > + > +#else > +#define ma35_nand_suspend NULL > +#define ma35_nand_resume NULL > +#endif > + > +static const struct of_device_id ma35_nfi_of_match[] = { ma35_nfi or ma35_nand, take one and please stick to it. > + { .compatible = "nuvoton,ma35d1-nand" }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, ma35_nfi_of_match); > + > +static struct platform_driver ma35_nand_driver = { > + .driver = { > + .name = "ma35d1-nand", > + .of_match_table = ma35_nfi_of_match, > + }, > + .probe = ma35_nand_probe, > + .remove = ma35_nand_remove, > + .suspend = ma35_nand_suspend, > + .resume = ma35_nand_resume, > +}; > + > +module_platform_driver(ma35_nand_driver); > + > +MODULE_DESCRIPTION("Nuvoton ma35 NAND driver"); > +MODULE_AUTHOR("Hui-Ping Chen <hpchen0nvt@xxxxxxxxx>"); > +MODULE_LICENSE("GPL"); Thanks, Miquèl