Re: [PATCH v4 3/5] spi: spi-qpic: Add qpic spi nand driver support

From: Miquel Raynal
Date: Fri Mar 15 2024 - 08:08:55 EST

Hi,

quic_mdalam@xxxxxxxxxxx wrote on Fri, 8 Mar 2024 14:47:50 +0530:

> Add qpic spi nand driver support. The spi nand
> driver currently supported the below commands.
>
> -- RESET
> -- READ ID
> -- SET FEATURE
> -- GET FEATURE
> -- READ PAGE
> -- WRITE PAGE
> -- ERASE PAGE
>
> Co-developed-by: Sricharan Ramabadhran <quic_srichara@xxxxxxxxxxx>
> Signed-off-by: Sricharan Ramabadhran <quic_srichara@xxxxxxxxxxx>
> Co-developed-by: Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> Signed-off-by: Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> Signed-off-by: Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>

I don't like the "spi nand driver" wording here. It is a spi
controller, for spi-memories.

Plus, I'd expect some kind of check to see whether you support the
requested operation, I don't see any in the code.


> ---
> Change in [v4]
>
> * No change
>
> Change in [v3]
>
> * Set SPI_QPIC_SNAND to n and added COMPILE_TEST in Kconfig
>
> * Made driver name sorted in Make file
>
> * Made comment like c++
>
> * Changed macro to functions, snandc_set_read_loc_last()
> and snandc_set_read_loc_first()
>
> * Added error handling in snandc_set_reg()
>
> * Changed into normal conditional statement for
> return snandc->ecc_stats.failed ? -EBADMSG :
> snandc->ecc_stats.bitflips;
>
> * Remove cast of wbuf in qpic_snand_program_execute()
> function
>
> * Made num_cw variable instead hardcoded value
>
> * changed if..else condition of function qpic_snand_io_op()
> to switch..case statement
>
> * Added __devm_spi_alloc_controller() api instead of
> devm_spi_alloc_master()
>
> * Disabling clock in remove path
>
> Change in [v2]
>
> * Added initial support for SPI-NAND driver
>
> Change in [v1]
>
> * Added RFC patch for design review
>
> drivers/mtd/nand/qpic_common.c | 8 +
> drivers/spi/Kconfig | 8 +
> drivers/spi/Makefile | 1 +
> drivers/spi/spi-qpic-snand.c | 1041 ++++++++++++++++++++++++++
> include/linux/mtd/nand-qpic-common.h | 61 ++
> 5 files changed, 1119 insertions(+)
> create mode 100644 drivers/spi/spi-qpic-snand.c
>
> diff --git a/drivers/mtd/nand/qpic_common.c b/drivers/mtd/nand/qpic_common.c
> index 5b7c0d119d9a..67ccb3d05f20 100644
> --- a/drivers/mtd/nand/qpic_common.c
> +++ b/drivers/mtd/nand/qpic_common.c
> @@ -134,6 +134,14 @@ __le32 *qcom_offset_to_nandc_reg(struct nandc_regs *regs, int offset)
> return &regs->read_location_last2;
> case NAND_READ_LOCATION_LAST_CW_3:
> return &regs->read_location_last3;
> + case NAND_FLASH_SPI_CFG:
> + return &regs->spi_cfg;
> + case NAND_NUM_ADDR_CYCLES:
> + return &regs->num_addr_cycle;
> + case NAND_BUSY_CHECK_WAIT_CNT:
> + return &regs->busy_wait_cnt;
> + case NAND_FLASH_FEATURES:
> + return &regs->flash_feature;

I am still not convinced about these. I don't understand who you have
this indirection.

> default:
> return NULL;
> }
> diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig
> index bc7021da2fe9..63764e943d82 100644
> --- a/drivers/spi/Kconfig
> +++ b/drivers/spi/Kconfig
> @@ -882,6 +882,14 @@ config SPI_QCOM_QSPI
> help
> QSPI(Quad SPI) driver for Qualcomm QSPI controller.
>
> +config SPI_QPIC_SNAND
> + tristate "QPIC SNAND controller"
> + depends on ARCH_QCOM || COMPILE_TEST
> + help
> + QPIC_SNAND (QPIC SPI NAND) driver for Qualcomm QPIC controller.
> + QPIC controller supports both parallel nand and serial nand.
> + This config will enable serial nand driver for QPIC controller.
> +
> config SPI_QUP
> tristate "Qualcomm SPI controller with QUP interface"
> depends on ARCH_QCOM || COMPILE_TEST
> diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile
> index 4ff8d725ba5e..9015368f8c73 100644
> --- a/drivers/spi/Makefile
> +++ b/drivers/spi/Makefile
> @@ -111,6 +111,7 @@ obj-$(CONFIG_SPI_PXA2XX) += spi-pxa2xx-platform.o
> obj-$(CONFIG_SPI_PXA2XX_PCI) += spi-pxa2xx-pci.o
> obj-$(CONFIG_SPI_QCOM_GENI) += spi-geni-qcom.o
> obj-$(CONFIG_SPI_QCOM_QSPI) += spi-qcom-qspi.o
> +obj-$(CONFIG_SPI_QPIC_SNAND) += spi-qpic-snand.o
> obj-$(CONFIG_SPI_QUP) += spi-qup.o
> obj-$(CONFIG_SPI_ROCKCHIP) += spi-rockchip.o
> obj-$(CONFIG_SPI_ROCKCHIP_SFC) += spi-rockchip-sfc.o
> diff --git a/drivers/spi/spi-qpic-snand.c b/drivers/spi/spi-qpic-snand.c
> new file mode 100644
> index 000000000000..df7d5d8d4db2
> --- /dev/null
> +++ b/drivers/spi/spi-qpic-snand.c
> @@ -0,0 +1,1041 @@
> +/*
> + * SPDX-License-Identifier: GPL-2.0
> + *
> + * Copyright (c) 2023, Qualcomm Innovation Center, Inc. All rights reserved.
> + *
> + * Authors:
> + * Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>
> + * Sricharan R <quic_srichara@xxxxxxxxxxx>
> + * Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> + */
> +
> +#include <linux/mtd/spinand.h>
> +#include <linux/mtd/nand-qpic-common.h>
> +
> +/* QSPI NAND config reg bits */
> +#define LOAD_CLK_CNTR_INIT_EN BIT(28)
> +#define CLK_CNTR_INIT_VAL_VEC 0x924
> +#define FEA_STATUS_DEV_ADDR 0xc0
> +#define SPI_CFG BIT(0)
> +#define SPI_NUM_ADDR 0xDA4DB
> +#define SPI_WAIT_CNT 0x10
> +#define QPIC_QSPI_NUM_CS 1
> +#define SPI_TRANSFER_MODE_x1 BIT(29)
> +#define SPI_TRANSFER_MODE_x4 (3 << 29)
> +#define SPI_WP BIT(28)
> +#define SPI_HOLD BIT(27)
> +#define QPIC_SET_FEATURE BIT(31)
> +
> +#define SPINAND_RESET 0xff
> +#define SPINAND_READID 0x9f
> +#define SPINAND_GET_FEATURE 0x0f
> +#define SPINAND_SET_FEATURE 0x1f
> +#define SPINAND_READ 0x13
> +#define SPINAND_ERASE 0xd8
> +#define SPINAND_WRITE_EN 0x06
> +#define SPINAND_PROGRAM_EXECUTE 0x10
> +#define SPINAND_PROGRAM_LOAD 0x84
> +
> +struct qpic_snand_op {
> + u32 cmd_reg;
> + u32 addr1_reg;
> + u32 addr2_reg;
> +};
> +
> +struct snandc_read_status {
> + __le32 snandc_flash;
> + __le32 snandc_buffer;
> + __le32 snandc_erased_cw;
> +};
> +
> +static void snandc_set_reg(struct qcom_nand_controller *snandc, int offset, u32 val)

qcom_spi_ would be a better prefix maybe?

> +{
> + struct nandc_regs *regs = snandc->regs;
> + __le32 *reg;
> +
> + reg = qcom_offset_to_nandc_reg(regs, offset);
> +
> + if (reg)
> + *reg = cpu_to_le32(val);
> +
> + if (WARN_ON(!reg))
> + return;

This whole logic really seems suboptimal.

> +}
> +
> +static void snandc_set_read_loc_first(struct qcom_nand_controller *snandc,
> + int reg, int cw_offset, int read_size,
> + int is_last_read_loc)
> +{
> + snandc_set_reg(snandc, reg, ((cw_offset) << READ_LOCATION_OFFSET) |
> + ((read_size) << READ_LOCATION_SIZE) | ((is_last_read_loc)
> + << READ_LOCATION_LAST));

FIELD_GET, FIELD_PREP ?

> +}
> +
> +static void snandc_set_read_loc_last(struct qcom_nand_controller *snandc,
> + int reg, int cw_offset, int read_size,
> + int is_last_read_loc)
> +{
> + snandc_set_reg(snandc, reg, ((cw_offset) << READ_LOCATION_OFFSET) |
> + ((read_size) << READ_LOCATION_SIZE) | ((is_last_read_loc)
> + << READ_LOCATION_LAST));
> +}
> +
> +static struct qcom_nand_controller *nand_to_qcom_snand(struct nand_device *nand)
> +{
> + struct nand_ecc_engine *eng = nand->ecc.engine;
> +
> + return container_of(eng, struct qcom_nand_controller, ecc_eng);
> +}
> +
> +static int qcom_snand_init(struct qcom_nand_controller *snandc)
> +{
> + u32 snand_cfg_val = 0x0;
> + int ret;
> +
> + snand_cfg_val |= (LOAD_CLK_CNTR_INIT_EN | (CLK_CNTR_INIT_VAL_VEC << 16)
> + | (FEA_STATUS_DEV_ADDR << 8) | SPI_CFG);

^
the | should be on the previous line.

> +
> + snandc_set_reg(snandc, NAND_FLASH_SPI_CFG, 0);
> + snandc_set_reg(snandc, NAND_FLASH_SPI_CFG, snand_cfg_val);
> + snandc_set_reg(snandc, NAND_NUM_ADDR_CYCLES, SPI_NUM_ADDR);
> + snandc_set_reg(snandc, NAND_BUSY_CHECK_WAIT_CNT, SPI_WAIT_CNT);
> +
> + qcom_write_reg_dma(snandc, NAND_FLASH_SPI_CFG, 1, 0);
> + qcom_write_reg_dma(snandc, NAND_FLASH_SPI_CFG, 1, 0);
> +
> + snand_cfg_val &= ~LOAD_CLK_CNTR_INIT_EN;
> + snandc_set_reg(snandc, NAND_FLASH_SPI_CFG, snand_cfg_val);
> +
> + qcom_write_reg_dma(snandc, NAND_FLASH_SPI_CFG, 1, 0);
> +
> + qcom_write_reg_dma(snandc, NAND_NUM_ADDR_CYCLES, 1, 0);
> + qcom_write_reg_dma(snandc, NAND_BUSY_CHECK_WAIT_CNT, 1, NAND_BAM_NEXT_SGL);
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret)
> + dev_err(snandc->dev, "failure in sbumitting spiinit descriptor\n");

Typos...

> +
> + return 0;

return ret ?

> +}
> +
> +static int qcom_snand_ooblayout_ecc(struct mtd_info *mtd, int section,
> + struct mtd_oob_region *oobregion)
> +{
> + struct nand_device *nand = mtd_to_nanddev(mtd);
> + struct qcom_nand_controller *snandc = nand_to_qcom_snand(nand);
> + struct qpic_ecc *qecc = snandc->ecc;
> +
> + if (section > 1)
> + return -ERANGE;
> +
> + if (!section) {
> + oobregion->length = (qecc->bytes * (qecc->steps - 1)) + qecc->bbm_size;
> + oobregion->offset = 0;

No BBM?

> + } else {
> + oobregion->length = qecc->ecc_bytes_hw + qecc->spare_bytes;
> + oobregion->offset = mtd->oobsize - oobregion->length;
> + }
> +
> + return 0;
> +}
> +
> +static int qcom_snand_ooblayout_free(struct mtd_info *mtd, int section,
> + struct mtd_oob_region *oobregion)
> +{
> + struct nand_device *nand = mtd_to_nanddev(mtd);
> + struct qcom_nand_controller *snandc = nand_to_qcom_snand(nand);
> + struct qpic_ecc *qecc = snandc->ecc;
> +
> + if (section)
> + return -ERANGE;
> +
> + oobregion->length = qecc->steps * 4;
> + oobregion->offset = ((qecc->steps - 1) * qecc->bytes) + qecc->bbm_size;
> +

Using the same order would be easier to compare with the above version

> + return 0;
> +}
> +
> +static const struct mtd_ooblayout_ops qcom_snand_ooblayout = {
> + .ecc = qcom_snand_ooblayout_ecc,
> + .free = qcom_snand_ooblayout_free,
> +};
> +
> +static int qpic_snand_ecc_init_ctx_pipelined(struct nand_device *nand)
> +{
> + struct qcom_nand_controller *snandc = nand_to_qcom_snand(nand);
> + struct nand_ecc_props *conf = &nand->ecc.ctx.conf;
> + struct nand_ecc_props *reqs = &nand->ecc.requirements;
> + struct nand_ecc_props *user = &nand->ecc.user_conf;
> + struct mtd_info *mtd = nanddev_to_mtd(nand);
> + int step_size = 0, strength = 0, steps;
> + int cwperpage, bad_block_byte;
> + struct qpic_ecc *ecc_cfg;
> +
> + cwperpage = mtd->writesize / NANDC_STEP_SIZE;
> + snandc->num_cw = cwperpage;
> +
> + ecc_cfg = kzalloc(sizeof(*ecc_cfg), GFP_KERNEL);
> + if (!ecc_cfg)
> + return -ENOMEM;
> +
> + nand->ecc.ctx.priv = ecc_cfg;
> +
> + if (user->step_size && user->strength) {
> + step_size = user->step_size;
> + strength = user->strength;
> + } else if (reqs->step_size && reqs->strength) {
> + step_size = reqs->step_size;
> + strength = reqs->strength;
> + }
> +
> + if (step_size && strength)
> + steps = mtd->writesize / step_size;
> +
> + ecc_cfg->ecc_bytes_hw = 7;
> + ecc_cfg->spare_bytes = 4;
> + ecc_cfg->bbm_size = 1;
> + ecc_cfg->bch_enabled = true;
> + ecc_cfg->bytes = ecc_cfg->ecc_bytes_hw + ecc_cfg->spare_bytes + ecc_cfg->bbm_size;
> +
> + ecc_cfg->steps = 4;
> + ecc_cfg->strength = 4;
> + ecc_cfg->step_size = 512;
> +
> + mtd_set_ooblayout(mtd, &qcom_snand_ooblayout);
> +
> + ecc_cfg->cw_data = 516;
> + ecc_cfg->cw_size = ecc_cfg->cw_data + ecc_cfg->bytes;
> + bad_block_byte = mtd->writesize - ecc_cfg->cw_size * (cwperpage - 1) + 1;
> +
> + ecc_cfg->cfg0 = (cwperpage - 1) << CW_PER_PAGE
> + | ecc_cfg->cw_data << UD_SIZE_BYTES
> + | 1 << DISABLE_STATUS_AFTER_WRITE
> + | 3 << NUM_ADDR_CYCLES
> + | ecc_cfg->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_RS
> + | 0 << STATUS_BFR_READ
> + | 1 << SET_RD_MODE_AFTER_STATUS
> + | ecc_cfg->spare_bytes << SPARE_SIZE_BYTES;
> +
> + ecc_cfg->cfg1 = 0 << NAND_RECOVERY_CYCLES
> + | 0 << CS_ACTIVE_BSY
> + | bad_block_byte << BAD_BLOCK_BYTE_NUM
> + | 0 << BAD_BLOCK_IN_SPARE_AREA
> + | 20 << WR_RD_BSY_GAP
> + | 0 << WIDE_FLASH
> + | ecc_cfg->bch_enabled << ENABLE_BCH_ECC;
> +
> + ecc_cfg->cfg0_raw = (cwperpage - 1) << CW_PER_PAGE
> + | ecc_cfg->cw_size << UD_SIZE_BYTES
> + | 3 << NUM_ADDR_CYCLES
> + | 0 << SPARE_SIZE_BYTES;
> +
> + ecc_cfg->cfg1_raw = 0 << NAND_RECOVERY_CYCLES
> + | 0 << CS_ACTIVE_BSY
> + | 17 << BAD_BLOCK_BYTE_NUM
> + | 1 << BAD_BLOCK_IN_SPARE_AREA
> + | 20 << WR_RD_BSY_GAP
> + | 0 << WIDE_FLASH
> + | 1 << DEV0_CFG1_ECC_DISABLE;
> +
> + ecc_cfg->ecc_bch_cfg = !ecc_cfg->bch_enabled << ECC_CFG_ECC_DISABLE
> + | 0 << ECC_SW_RESET
> + | ecc_cfg->cw_data << ECC_NUM_DATA_BYTES
> + | 1 << ECC_FORCE_CLK_OPEN
> + | 0 << ECC_MODE
> + | ecc_cfg->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_BCH;
> +
> + ecc_cfg->ecc_buf_cfg = 0x203 << NUM_STEPS;
> + ecc_cfg->clrflashstatus = FS_READY_BSY_N;
> + ecc_cfg->clrreadstatus = 0xc0;
> +
> + conf->step_size = ecc_cfg->step_size;
> + conf->strength = ecc_cfg->strength;
> +
> + if (ecc_cfg->strength < strength)
> + dev_warn(snandc->dev, "Unable to fulfill ECC requirements of %u bits.\n", strength);

Not needed I guess. Somewhat redundant with the core?

> +
> + dev_info(snandc->dev, "ECC strength: %u bits per %u bytes\n",
> + ecc_cfg->strength, ecc_cfg->step_size);

Debug?

> +
> + return 0;
> +}
> +
> +static void qpic_snand_ecc_cleanup_ctx_pipelined(struct nand_device *nand)
> +{
> + struct qpic_ecc *ecc_cfg = nand_to_ecc_ctx(nand);
> +
> + kfree(ecc_cfg);
> +}
> +
> +static int qpic_snand_ecc_prepare_io_req_pipelined(struct nand_device *nand,
> + struct nand_page_io_req *req)
> +{
> + struct qcom_nand_controller *snandc = nand_to_qcom_snand(nand);
> + struct qpic_ecc *ecc_cfg = nand_to_ecc_ctx(nand);
> +
> + snandc->ecc = ecc_cfg;
> + snandc->raw = false;
> + snandc->oob_read = false;
> +
> + if (req->mode == MTD_OPS_RAW) {
> + if (req->ooblen)
> + snandc->oob_read = true;
> + snandc->raw = true;
> + }
> +
> + return 0;
> +}
> +
> +static int qpic_snand_ecc_finish_io_req_pipelined(struct nand_device *nand,
> + struct nand_page_io_req *req)
> +{
> + struct qcom_nand_controller *snandc = nand_to_qcom_snand(nand);
> + struct mtd_info *mtd = nanddev_to_mtd(nand);
> +
> + if (req->mode == MTD_OPS_RAW || req->type != NAND_PAGE_READ)
> + return 0;
> +
> + if (snandc->ecc_stats.failed)
> + mtd->ecc_stats.failed += snandc->ecc_stats.failed;
> + mtd->ecc_stats.corrected += snandc->ecc_stats.corrected;
> +
> + if (snandc->ecc_stats.failed)

I hope you reset this counter at some point.

Did you run nandbiterrs -i ?

> + return -EBADMSG;
> + else
> + return snandc->ecc_stats.bitflips;
> +}
> +
> +static struct nand_ecc_engine_ops qcom_snand_ecc_engine_ops_pipelined = {
> + .init_ctx = qpic_snand_ecc_init_ctx_pipelined,
> + .cleanup_ctx = qpic_snand_ecc_cleanup_ctx_pipelined,
> + .prepare_io_req = qpic_snand_ecc_prepare_io_req_pipelined,
> + .finish_io_req = qpic_snand_ecc_finish_io_req_pipelined,
> +};
> +
> +/* helper to configure location register values */
> +static void snandc_set_read_loc(struct qcom_nand_controller *snandc, int cw, int reg,
> + int cw_offset, int read_size, int is_last_read_loc)
> +{
> + int reg_base = NAND_READ_LOCATION_0;
> +
> + if (cw == 3)
> + reg_base = NAND_READ_LOCATION_LAST_CW_0;
> +
> + reg_base += reg * 4;
> +
> + if (cw == 3)
> + return snandc_set_read_loc_last(snandc, reg_base, cw_offset,
> + read_size, is_last_read_loc);

Alignments are still wrong, again.

> + else
> + return snandc_set_read_loc_first(snandc, reg_base, cw_offset,
> + read_size, is_last_read_loc);
> +}
> +
> +static void
> +snandc_config_cw_read(struct qcom_nand_controller *snandc, bool use_ecc, int cw)
> +{
> + int reg = NAND_READ_LOCATION_0;
> +
> + if (cw == 3)
> + reg = NAND_READ_LOCATION_LAST_CW_0;
> +
> + if (snandc->props->is_bam)
> + qcom_write_reg_dma(snandc, reg, 4, NAND_BAM_NEXT_SGL);
> +
> + qcom_write_reg_dma(snandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +
> + qcom_read_reg_dma(snandc, NAND_FLASH_STATUS, 2, 0);
> + qcom_read_reg_dma(snandc, NAND_ERASED_CW_DETECT_STATUS, 1,
> + NAND_BAM_NEXT_SGL);
> +}
> +
> +static int qpic_snand_block_erase(struct qcom_nand_controller *snandc)
> +{
> + struct qpic_ecc *ecc_cfg = snandc->ecc;
> + int ret;
> +
> + snandc->buf_count = 0;
> + snandc->buf_start = 0;
> + qcom_clear_read_regs(snandc);
> + qcom_clear_bam_transaction(snandc);
> +
> + snandc_set_reg(snandc, NAND_FLASH_CMD, snandc->cmd);
> + snandc_set_reg(snandc, NAND_ADDR0, snandc->addr1);
> + snandc_set_reg(snandc, NAND_ADDR1, snandc->addr2);
> + snandc_set_reg(snandc, NAND_DEV0_CFG0, ecc_cfg->cfg0_raw & ~(7 << CW_PER_PAGE));
> + snandc_set_reg(snandc, NAND_DEV0_CFG1, ecc_cfg->cfg1_raw);
> + snandc_set_reg(snandc, NAND_EXEC_CMD, 1);
> +
> + qcom_write_reg_dma(snandc, NAND_FLASH_CMD, 3, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_DEV0_CFG0, 2, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret) {
> + dev_err(snandc->dev, "failure to erase block\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void config_snand_single_cw_page_read(struct qcom_nand_controller *snandc,
> + bool use_ecc, int cw)
> +{
> + int reg;
> +
> + qcom_write_reg_dma(snandc, NAND_ADDR0, 2, 0);
> + qcom_write_reg_dma(snandc, NAND_DEV0_CFG0, 3, 0);
> + qcom_write_reg_dma(snandc, NAND_ERASED_CW_DETECT_CFG, 1, 0);
> + qcom_write_reg_dma(snandc, NAND_ERASED_CW_DETECT_CFG, 1,
> + NAND_ERASED_CW_SET | NAND_BAM_NEXT_SGL);
> +
> + reg = NAND_READ_LOCATION_0;
> + if (cw == 3)

This is hardcoded everywhere, I am not a big fan.

> + reg = NAND_READ_LOCATION_LAST_CW_0;
> + qcom_write_reg_dma(snandc, reg, 4, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +
> + qcom_read_reg_dma(snandc, NAND_FLASH_STATUS, 2, 0);
> + qcom_read_reg_dma(snandc, NAND_ERASED_CW_DETECT_STATUS, 1, NAND_BAM_NEXT_SGL);
> +}
> +
> +static int qpic_snand_read_oob(struct qcom_nand_controller *snandc,
> + const struct spi_mem_op *op)
> +{
> + struct qpic_ecc *ecc_cfg = snandc->ecc;
> + int size, ret;
> + int col, bbpos;
> + u32 cfg0, cfg1, ecc_bch_cfg;
> + u32 num_cw = snandc->num_cw;
> +
> + qcom_clear_bam_transaction(snandc);
> + qcom_clear_read_regs(snandc);
> +
> + size = ecc_cfg->cw_size;
> + col = ecc_cfg->cw_size * (num_cw - 1);
> +
> + /* prepare a clean read buffer */
> + memset(snandc->data_buffer, 0xff, size);
> + snandc_set_reg(snandc, NAND_ADDR0, (snandc->addr1 | col));
> + snandc_set_reg(snandc, NAND_ADDR1, snandc->addr2);
> +
> + cfg0 = (ecc_cfg->cfg0_raw & ~(7U << CW_PER_PAGE)) |
> + 0 << CW_PER_PAGE;
> + cfg1 = ecc_cfg->cfg1_raw;
> + ecc_bch_cfg = 1 << ECC_CFG_ECC_DISABLE;
> +
> + snandc_set_reg(snandc, NAND_FLASH_CMD, snandc->cmd);
> + snandc_set_reg(snandc, NAND_DEV0_CFG0, cfg0);
> + snandc_set_reg(snandc, NAND_DEV0_CFG1, cfg1);
> + snandc_set_reg(snandc, NAND_DEV0_ECC_CFG, ecc_bch_cfg);
> + snandc_set_reg(snandc, NAND_EXEC_CMD, 1);
> +
> + config_snand_single_cw_page_read(snandc, false, num_cw - 1);
> +
> + qcom_read_data_dma(snandc, FLASH_BUF_ACC, snandc->data_buffer, size, 0);
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret)
> + dev_err(snandc->dev, "failed to read oob\n");

Why don't you return here?

> +
> + qcom_nandc_read_buffer_sync(snandc, true);
> + u32 flash = le32_to_cpu(snandc->reg_read_buf[0]);

No compiler warning here?

> +
> + if (flash & (FS_OP_ERR | FS_MPU_ERR))
> + return -EIO;
> +
> + bbpos = 2048 - ecc_cfg->cw_size * (num_cw - 1);

Why is this size hardcoded?! That cannot work!

> + memcpy(op->data.buf.in, snandc->data_buffer + bbpos, op->data.nbytes);
> +
> + return ret;
> +}
> +
> +static int snandc_check_error(struct qcom_nand_controller *snandc)
> +{
> + struct snandc_read_status *buf;
> + int i, num_cw = snandc->num_cw;
> + bool serial_op_err = false, erased;
> +
> + qcom_nandc_read_buffer_sync(snandc, true);
> + buf = (struct snandc_read_status *)snandc->reg_read_buf;
> +
> + for (i = 0; i < num_cw; i++, buf++) {
> + u32 flash, buffer, erased_cw;
> +
> + flash = le32_to_cpu(buf->snandc_flash);
> + buffer = le32_to_cpu(buf->snandc_buffer);
> + erased_cw = le32_to_cpu(buf->snandc_erased_cw);
> +
> + if ((flash & FS_OP_ERR) && (buffer & BS_UNCORRECTABLE_BIT)) {
> + erased = (erased_cw & ERASED_CW) == ERASED_CW ?
> + true : false;

This ternary operation is useless

> + } else if (flash & (FS_OP_ERR | FS_MPU_ERR)) {
> + serial_op_err = true;
> + }
> + }
> +
> + if (serial_op_err)
> + return -EIO;
> +
> + return 0;
> +}
> +
> +static int qpic_snand_read_page_cache(struct qcom_nand_controller *snandc,
> + const struct spi_mem_op *op)
> +{
> + struct qpic_ecc *ecc_cfg = snandc->ecc;
> + u8 *data_buf;
> + int ret, i;
> + u32 cfg0, cfg1, ecc_bch_cfg, num_cw = snandc->num_cw;
> +
> + data_buf = op->data.buf.in;
> +
> + if (snandc->oob_read) {
> + return qpic_snand_read_oob(snandc, op);
> + snandc->oob_read = false;
> + }
> +
> + snandc->buf_count = 0;
> + snandc->buf_start = 0;
> + qcom_clear_read_regs(snandc);
> +
> + cfg0 = (ecc_cfg->cfg0 & ~(7U << CW_PER_PAGE)) |
> + (num_cw - 1) << CW_PER_PAGE;
> + cfg1 = ecc_cfg->cfg1;
> + ecc_bch_cfg = ecc_cfg->ecc_bch_cfg;
> +
> + snandc_set_reg(snandc, NAND_ADDR0, snandc->addr1);
> + snandc_set_reg(snandc, NAND_ADDR1, snandc->addr2);
> + snandc_set_reg(snandc, NAND_FLASH_CMD, snandc->cmd);
> + snandc_set_reg(snandc, NAND_DEV0_CFG0, cfg0);
> + snandc_set_reg(snandc, NAND_DEV0_CFG1, cfg1);
> + snandc_set_reg(snandc, NAND_DEV0_ECC_CFG, ecc_bch_cfg);
> + snandc_set_reg(snandc, NAND_FLASH_STATUS, ecc_cfg->clrflashstatus);
> + snandc_set_reg(snandc, NAND_READ_STATUS, ecc_cfg->clrreadstatus);
> + snandc_set_reg(snandc, NAND_EXEC_CMD, 1);
> + snandc_set_read_loc(snandc, 0, 0, 0, ecc_cfg->cw_data, 1);
> +
> + qcom_clear_bam_transaction(snandc);
> +
> + qcom_write_reg_dma(snandc, NAND_ADDR0, 2, 0);
> + qcom_write_reg_dma(snandc, NAND_DEV0_CFG0, 3, 0);
> + qcom_write_reg_dma(snandc, NAND_ERASED_CW_DETECT_CFG, 1, 0);
> + qcom_write_reg_dma(snandc, NAND_ERASED_CW_DETECT_CFG, 1,
> + NAND_ERASED_CW_SET | NAND_BAM_NEXT_SGL);
> +
> + for (i = 0; i < num_cw; i++) {
> + int data_size;
> +
> + if (i == (num_cw - 1))
> + data_size = 512 - ((num_cw - 1) << 2);
> + else
> + data_size = ecc_cfg->cw_data;
> +
> + if (data_buf)
> + snandc_set_read_loc(snandc, i, 0, 0, data_size, 1);
> +
> + snandc_config_cw_read(snandc, true, i);
> +
> + if (data_buf)
> + qcom_read_data_dma(snandc, FLASH_BUF_ACC, data_buf,
> + data_size, 0);
> +
> + if (data_buf)
> + data_buf += data_size;
> + }
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret) {
> + dev_err(snandc->dev, "failure to read page/oob\n");
> + return ret;
> + }
> +
> + return snandc_check_error(snandc);
> +}
> +
> +static void config_snand_page_write(struct qcom_nand_controller *snandc)
> +{
> + qcom_write_reg_dma(snandc, NAND_ADDR0, 2, 0);
> + qcom_write_reg_dma(snandc, NAND_DEV0_CFG0, 3, 0);
> + qcom_write_reg_dma(snandc, NAND_EBI2_ECC_BUF_CFG, 1, NAND_BAM_NEXT_SGL);
> +}
> +
> +static void config_snand_cw_write(struct qcom_nand_controller *snandc)
> +{
> + qcom_write_reg_dma(snandc, NAND_FLASH_CMD, 1, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +}
> +
> +static int qpic_snand_program_execute(struct qcom_nand_controller *snandc,
> + const struct spi_mem_op *op)
> +{
> + struct qpic_ecc *ecc_cfg = snandc->ecc;
> + u8 *data_buf;
> + int i, ret;
> + int num_cw = snandc->num_cw;
> + u32 cfg0, cfg1, ecc_bch_cfg, ecc_buf_cfg;
> +
> + cfg0 = (ecc_cfg->cfg0 & ~(7U << CW_PER_PAGE)) |
> + (num_cw - 1) << CW_PER_PAGE;
> + cfg1 = ecc_cfg->cfg1;
> + ecc_bch_cfg = ecc_cfg->ecc_bch_cfg;
> + ecc_buf_cfg = ecc_cfg->ecc_buf_cfg;
> +
> + data_buf = snandc->wbuf;
> +
> + snandc->buf_count = 0;
> + snandc->buf_start = 0;
> + qcom_clear_read_regs(snandc);
> + qcom_clear_bam_transaction(snandc);
> +
> + snandc_set_reg(snandc, NAND_ADDR0, snandc->addr1);
> + snandc_set_reg(snandc, NAND_ADDR1, snandc->addr2);
> + snandc_set_reg(snandc, NAND_FLASH_CMD, snandc->cmd);
> +
> + snandc_set_reg(snandc, NAND_DEV0_CFG0, cfg0);
> + snandc_set_reg(snandc, NAND_DEV0_CFG1, cfg1);
> + snandc_set_reg(snandc, NAND_DEV0_ECC_CFG, ecc_bch_cfg);
> +
> + snandc_set_reg(snandc, NAND_EBI2_ECC_BUF_CFG, ecc_buf_cfg);
> +
> + snandc_set_reg(snandc, NAND_EXEC_CMD, 1);
> +
> + config_snand_page_write(snandc);
> +
> + for (i = 0; i < num_cw; i++) {
> + int data_size;
> +
> + if (i == (num_cw - 1))
> + data_size = NANDC_STEP_SIZE - ((num_cw - 1) << 2);
> + else
> + data_size = ecc_cfg->cw_data;
> +
> + qcom_write_data_dma(snandc, FLASH_BUF_ACC, data_buf, data_size,
> + i == (num_cw - 1) ? NAND_BAM_NO_EOT : 0);
> +
> + config_snand_cw_write(snandc);
> + if (data_buf)
> + data_buf += data_size;
> + }
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret) {
> + dev_err(snandc->dev, "failure to write page\n");
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static u32 qpic_snand_cmd_mapping(struct qcom_nand_controller *snandc, u32 opcode)
> +{
> + u32 cmd = 0x0;
> +
> + switch (opcode) {
> + case SPINAND_RESET:
> + cmd = (SPI_WP | SPI_HOLD | SPI_TRANSFER_MODE_x1 | OP_RESET_DEVICE);
> + break;
> + case SPINAND_READID:
> + cmd = (SPI_WP | SPI_HOLD | SPI_TRANSFER_MODE_x1 | OP_FETCH_ID);
> + break;
> + case SPINAND_GET_FEATURE:
> + cmd = (SPI_TRANSFER_MODE_x1 | SPI_WP | SPI_HOLD | ACC_FEATURE);
> + break;
> + case SPINAND_SET_FEATURE:
> + cmd = (SPI_TRANSFER_MODE_x1 | SPI_WP | SPI_HOLD | ACC_FEATURE |
> + QPIC_SET_FEATURE);
> + break;
> + case SPINAND_READ:
> + if (snandc->raw)
> + cmd = (PAGE_ACC | LAST_PAGE | SPI_TRANSFER_MODE_x1 |
> + SPI_WP | SPI_HOLD | OP_PAGE_READ);
> + else
> + cmd = (PAGE_ACC | LAST_PAGE | SPI_TRANSFER_MODE_x1 |
> + SPI_WP | SPI_HOLD | OP_PAGE_READ_WITH_ECC);
> + break;
> + case SPINAND_ERASE:
> + cmd = OP_BLOCK_ERASE | PAGE_ACC | LAST_PAGE | SPI_WP |
> + SPI_HOLD | SPI_TRANSFER_MODE_x1;
> + break;
> + case SPINAND_WRITE_EN:
> + cmd = SPINAND_WRITE_EN;
> + break;
> + case SPINAND_PROGRAM_EXECUTE:
> + cmd = (PAGE_ACC | LAST_PAGE | SPI_TRANSFER_MODE_x1 |
> + SPI_WP | SPI_HOLD | OP_PROGRAM_PAGE);
> + break;
> + case SPINAND_PROGRAM_LOAD:
> + cmd = SPINAND_PROGRAM_LOAD;
> + break;
> + default:
> + break;

No, no, no and no again. You've been sending NAND contributions for
years, and you still continue to assume all the commands are defined
and we will never check for supported ops. Please.

> + }
> +
> + return cmd;
> +}
> +
> +static int qpic_snand_write_page_cache(struct qcom_nand_controller *snandc,
> + const struct spi_mem_op *op)
> +{
> + struct qpic_snand_op s_op = {};
> + u32 cmd;
> +
> + cmd = qpic_snand_cmd_mapping(snandc, op->cmd.opcode);
> + s_op.cmd_reg = cmd;
> +
> + if (op->cmd.opcode == SPINAND_PROGRAM_LOAD) {
> + snandc->wbuf = (u8 *)op->data.buf.out;
> + snandc->wlen = op->data.nbytes;
> + }
> +
> + return 0;
> +}
> +
> +static int qpic_snand_send_cmdaddr(struct qcom_nand_controller *snandc,
> + const struct spi_mem_op *op)
> +{
> + struct qpic_snand_op s_op = {};
> + u32 cmd;
> + int ret;
> +
> + cmd = qpic_snand_cmd_mapping(snandc, op->cmd.opcode);
> +
> + s_op.cmd_reg = cmd;
> + s_op.addr1_reg = op->addr.val;
> + s_op.addr2_reg = 0;
> +
Would a switch case be more appropriate?

> + if (op->cmd.opcode == SPINAND_WRITE_EN)
> + return 0;
> +
> + if (op->cmd.opcode == SPINAND_PROGRAM_EXECUTE) {
> + s_op.addr1_reg = op->addr.val << 16;
> + s_op.addr2_reg = op->addr.val >> 16 & 0xff;
> + snandc->addr1 = s_op.addr1_reg;
> + snandc->addr2 = s_op.addr2_reg;
> + snandc->cmd = cmd;
> + return qpic_snand_program_execute(snandc, op);
> + }
> +
> + if (op->cmd.opcode == SPINAND_READ) {
> + s_op.addr1_reg = (op->addr.val << 16);
> + s_op.addr2_reg = op->addr.val >> 16 & 0xff;
> + snandc->addr1 = s_op.addr1_reg;
> + snandc->addr2 = s_op.addr2_reg;
> + snandc->cmd = cmd;
> + return 0;
> + }
> +
> + if (op->cmd.opcode == SPINAND_ERASE) {
> + s_op.addr2_reg = (op->addr.val >> 16) & 0xffff;
> + s_op.addr1_reg = op->addr.val;
> + snandc->addr1 = s_op.addr1_reg;
> + snandc->addr1 <<= 16;
> + snandc->addr2 = s_op.addr2_reg;
> + snandc->cmd = cmd;
> + qpic_snand_block_erase(snandc);
> + return 0;
> + }
> +
> + snandc->buf_count = 0;
> + snandc->buf_start = 0;
> + qcom_clear_read_regs(snandc);
> + qcom_clear_bam_transaction(snandc);
> +
> + snandc_set_reg(snandc, NAND_FLASH_CMD, s_op.cmd_reg);
> + snandc_set_reg(snandc, NAND_EXEC_CMD, 0x1);
> + snandc_set_reg(snandc, NAND_ADDR0, s_op.addr1_reg);
> + snandc_set_reg(snandc, NAND_ADDR1, s_op.addr2_reg);
> +
> + qcom_write_reg_dma(snandc, NAND_FLASH_CMD, 3, NAND_BAM_NEXT_SGL);
> + qcom_write_reg_dma(snandc, NAND_EXEC_CMD, 1, NAND_BAM_NEXT_SGL);
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret)
> + dev_err(snandc->dev, "failure in sbumitting cmd descriptor\n");
> +
> + return ret;
> +}
> +
> +static int qpic_snand_io_op(struct qcom_nand_controller *snandc, const struct spi_mem_op *op)
> +{
> + int ret, val, opcode;
> + bool copy = false, copy_ftr = false;
> +
> + ret = qpic_snand_send_cmdaddr(snandc, op);
> + if (ret)
> + return ret;
> +
> + snandc->buf_count = 0;
> + snandc->buf_start = 0;
> + qcom_clear_read_regs(snandc);
> + qcom_clear_bam_transaction(snandc);
> + opcode = op->cmd.opcode;
> +
> + switch (opcode) {
> + case SPINAND_READID:
> + snandc->buf_count = 4;
> + qcom_read_reg_dma(snandc, NAND_READ_ID, 1, NAND_BAM_NEXT_SGL);
> + copy = true;
> + break;
> + case SPINAND_GET_FEATURE:
> + snandc->buf_count = 4;
> + qcom_read_reg_dma(snandc, NAND_FLASH_FEATURES, 1, NAND_BAM_NEXT_SGL);
> + copy_ftr = true;
> + break;
> + case SPINAND_SET_FEATURE:
> + snandc_set_reg(snandc, NAND_FLASH_FEATURES, *(u32 *)op->data.buf.out);
> + qcom_write_reg_dma(snandc, NAND_FLASH_FEATURES, 1, NAND_BAM_NEXT_SGL);
> + break;
> + default:
> + return 0;
> + }
> +
> + ret = qcom_submit_descs(snandc);
> + if (ret)
> + dev_err(snandc->dev, "failure in submitting descriptor for:%d\n", opcode);
> +
> + if (copy) {
> + qcom_nandc_read_buffer_sync(snandc, true);
> + memcpy(op->data.buf.in, snandc->reg_read_buf, snandc->buf_count);
> + }
> +
> + if (copy_ftr) {
> + qcom_nandc_read_buffer_sync(snandc, true);
> + val = le32_to_cpu(*(__le32 *)snandc->reg_read_buf);
> + val >>= 8;
> + memcpy(op->data.buf.in, &val, snandc->buf_count);
> + }
> +
> + return ret;
> +}
> +
> +static bool qpic_snand_is_page_op(const struct spi_mem_op *op)
> +{
> + if (op->addr.buswidth != 1 && op->addr.buswidth != 2 && op->addr.buswidth != 4)
> + return false;
> +
> + if (op->data.dir == SPI_MEM_DATA_IN) {
> + if (op->addr.buswidth == 4 && op->data.buswidth == 4)
> + return true;
> +
> + if (op->addr.nbytes == 2 && op->addr.buswidth == 1)
> + return true;
> +
> + } else if (op->data.dir == SPI_MEM_DATA_OUT) {
> + if (op->data.buswidth == 4)
> + return true;
> + if (op->addr.nbytes == 2 && op->addr.buswidth == 1)
> + return true;
> + }
> +
> + return false;
> +}
> +
> +static bool qpic_snand_supports_op(struct spi_mem *mem, const struct spi_mem_op *op)
> +{
> + if (!spi_mem_default_supports_op(mem, op))
> + return false;
> +
> + if (op->cmd.nbytes != 1 || op->cmd.buswidth != 1)
> + return false;
> +
> + if (qpic_snand_is_page_op(op))
> + return true;
> +
> + return ((op->addr.nbytes == 0 || op->addr.buswidth == 1) &&

!op->addr.nbytes and so on

> + (op->dummy.nbytes == 0 || op->dummy.buswidth == 1) &&
> + (op->data.nbytes == 0 || op->data.buswidth == 1));
> +}
> +
> +static int qpic_snand_exec_op(struct spi_mem *mem, const struct spi_mem_op *op)
> +{
> + struct qcom_nand_controller *snandc = spi_controller_get_devdata(mem->spi->controller);
> +
> + dev_dbg(snandc->dev, "OP %02x ADDR %08llX@%d:%u DATA %d:%u", op->cmd.opcode,
> + op->addr.val, op->addr.buswidth, op->addr.nbytes,
> + op->data.buswidth, op->data.nbytes);
> +
> + if (qpic_snand_is_page_op(op)) {
> + if (op->data.dir == SPI_MEM_DATA_IN)
> + return qpic_snand_read_page_cache(snandc, op);
> + if (op->data.dir == SPI_MEM_DATA_OUT)
> + return qpic_snand_write_page_cache(snandc, op);
> + } else {
> + return qpic_snand_io_op(snandc, op);
> + }
> +
> + return 0;
> +}
> +
> +static const struct spi_controller_mem_ops qcom_spi_mem_ops = {
> + .supports_op = qpic_snand_supports_op,
> + .exec_op = qpic_snand_exec_op,
> +};
> +
> +static const struct spi_controller_mem_caps qcom_snand_mem_caps = {
> + .ecc = true,
> +};
> +
> +static int qcom_snand_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct spi_controller *ctlr;
> + struct qcom_nand_controller *snandc;
> + struct resource *res;
> + const void *dev_data;
> + struct qpic_ecc *ecc;
> + int ret;
> +
> + ecc = devm_kzalloc(dev, sizeof(*ecc), GFP_KERNEL);
> + if (!ecc)
> + return -ENOMEM;
> +
> + ctlr = __devm_spi_alloc_controller(dev, sizeof(*snandc), false);

I don't know if that is legitimate, why using __devm?

> + if (!ctlr)
> + return -ENOMEM;
> +
> + platform_set_drvdata(pdev, ctlr);
> +
> + snandc = spi_controller_get_devdata(ctlr);
> +
> + snandc->ctlr = ctlr;
> + snandc->dev = dev;
> + snandc->ecc = ecc;
> +
> + dev_data = of_device_get_match_data(dev);
> + if (!dev_data) {
> + dev_err(&pdev->dev, "failed to get device data\n");
> + return -ENODEV;
> + }
> +
> + snandc->props = dev_data;
> + snandc->dev = &pdev->dev;
> +
> + snandc->core_clk = devm_clk_get(dev, "core");
> + if (IS_ERR(snandc->core_clk))
> + return PTR_ERR(snandc->core_clk);
> +
> + snandc->aon_clk = devm_clk_get(dev, "aon");
> + if (IS_ERR(snandc->aon_clk))
> + return PTR_ERR(snandc->aon_clk);
> +
> + snandc->iomacro_clk = devm_clk_get(dev, "iom");
> + if (IS_ERR(snandc->iomacro_clk))
> + return PTR_ERR(snandc->iomacro_clk);
> +
> + snandc->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
> + if (IS_ERR(snandc->base))
> + return PTR_ERR(snandc->base);
> +
> + snandc->base_phys = res->start;
> + snandc->base_dma = dma_map_resource(dev, res->start, resource_size(res),
> + DMA_BIDIRECTIONAL, 0);
> + if (dma_mapping_error(dev, snandc->base_dma))
> + return -ENXIO;
> +
> + ret = clk_prepare_enable(snandc->core_clk);
> + if (ret)
> + goto err_core_clk;
> +
> + ret = clk_prepare_enable(snandc->aon_clk);
> + if (ret)
> + goto err_aon_clk;
> +
> + ret = clk_prepare_enable(snandc->iomacro_clk);
> + if (ret)
> + goto err_snandc_alloc;
> +
> + ret = qcom_nandc_alloc(snandc);
> + if (ret)
> + goto err_snandc_alloc;
> +
> + ret = qcom_snand_init(snandc);
> + if (ret)
> + goto err_init;
> +
> + /* setup ECC engine */
> + snandc->ecc_eng.dev = &pdev->dev;
> + snandc->ecc_eng.integration = NAND_ECC_ENGINE_INTEGRATION_PIPELINED;
> + snandc->ecc_eng.ops = &qcom_snand_ecc_engine_ops_pipelined;
> + snandc->ecc_eng.priv = snandc;
> +
> + ret = nand_ecc_register_on_host_hw_engine(&snandc->ecc_eng);
> + if (ret) {
> + dev_err(&pdev->dev, "failed to register ecc engine.\n");
> + goto err_init;
> + }
> +
> + ctlr->num_chipselect = QPIC_QSPI_NUM_CS;
> + ctlr->mem_ops = &qcom_spi_mem_ops;
> + ctlr->mem_caps = &qcom_snand_mem_caps;
> + ctlr->dev.of_node = pdev->dev.of_node;
> + ctlr->mode_bits = SPI_TX_DUAL | SPI_RX_DUAL |
> + SPI_TX_QUAD | SPI_RX_QUAD;
> +
> + ret = spi_register_controller(ctlr);
> + if (ret) {
> + dev_err(&pdev->dev, "spi_register_controller failed.\n");
> + goto err_init;
> + }
> +
> + return 0;
> +
> +err_init:
> + qcom_nandc_unalloc(snandc);
> +err_snandc_alloc:
> + clk_disable_unprepare(snandc->aon_clk);
> +err_aon_clk:
> + clk_disable_unprepare(snandc->core_clk);

Don't you miss one clock ?

> +err_core_clk:
> + dma_unmap_resource(dev, res->start, resource_size(res),
> + DMA_BIDIRECTIONAL, 0);
> + return ret;
> +}
> +
> +static int qcom_snand_remove(struct platform_device *pdev)
> +{
> + struct spi_controller *ctlr = platform_get_drvdata(pdev);
> + struct qcom_nand_controller *snandc = spi_controller_get_devdata(ctlr);
> + struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +
> + spi_unregister_controller(ctlr);
> +
> + clk_disable_unprepare(snandc->aon_clk);
> + clk_disable_unprepare(snandc->core_clk);
> + clk_disable_unprepare(snandc->iomacro_clk);
> +
> + dma_unmap_resource(&pdev->dev, snandc->base_dma, resource_size(res),
> + DMA_BIDIRECTIONAL, 0);
> + return 0;
> +}
> +
> +static const struct qcom_nandc_props ipq9574_snandc_props = {
> + .dev_cmd_reg_start = 0x7000,
> + .is_bam = true,

Same comment about "is_bam"

> +};
> +
> +static const struct of_device_id qcom_snandc_of_match[] = {
> + {
> + .compatible = "qcom,spi-qpic-snand",
> + .data = &ipq9574_snandc_props,
> + },
> + {}
> +}
> +MODULE_DEVICE_TABLE(of, qcom_snandc_of_match);
> +
> +static struct platform_driver qcom_snand_driver = {
> + .driver = {
> + .name = "qcom_snand",
> + .of_match_table = qcom_snandc_of_match,
> + },
> + .probe = qcom_snand_probe,
> + .remove = qcom_snand_remove,
> +};
> +module_platform_driver(qcom_snand_driver);
> +
> +MODULE_DESCRIPTION("SPI driver for QPIC QSPI cores");
> +MODULE_AUTHOR("Md Sadre Alam <quic_mdalam@xxxxxxxxxxx>");
> +MODULE_LICENSE("GPL");
> diff --git a/include/linux/mtd/nand-qpic-common.h b/include/linux/mtd/nand-qpic-common.h
> index aced15866627..4673cd36ff0a 100644
> --- a/include/linux/mtd/nand-qpic-common.h
> +++ b/include/linux/mtd/nand-qpic-common.h
> @@ -45,6 +45,9 @@
> #define NAND_DEV_CMD1 0xa4
> #define NAND_DEV_CMD2 0xa8
> #define NAND_DEV_CMD_VLD 0xac
> +#define NAND_FLASH_SPI_CFG 0xc0
> +#define NAND_NUM_ADDR_CYCLES 0xc4
> +#define NAND_BUSY_CHECK_WAIT_CNT 0xc8

If this is specific to the spi-nand implementation, then it's not
common and has no reason to be shared here. Same for the other
definitions of course.

> #define SFLASHC_BURST_CFG 0xe0
> #define NAND_ERASED_CW_DETECT_CFG 0xe8
> #define NAND_ERASED_CW_DETECT_STATUS 0xec
> @@ -61,6 +64,7 @@
> #define NAND_READ_LOCATION_LAST_CW_1 0xf44
> #define NAND_READ_LOCATION_LAST_CW_2 0xf48
> #define NAND_READ_LOCATION_LAST_CW_3 0xf4c
> +#define NAND_FLASH_FEATURES 0xf64
>
> /* dummy register offsets, used by write_reg_dma */
> #define NAND_DEV_CMD1_RESTORE 0xdead
> @@ -169,6 +173,7 @@
> #define OP_CHECK_STATUS 0xc
> #define OP_FETCH_ID 0xb
> #define OP_RESET_DEVICE 0xd
> +#define ACC_FEATURE 0xe
>
> /* Default Value for NAND_DEV_CMD_VLD */
> #define NAND_DEV_CMD_VLD_VAL (READ_START_VLD | WRITE_START_VLD | \
> @@ -329,11 +334,53 @@ struct nandc_regs {
> __le32 read_location_last1;
> __le32 read_location_last2;
> __le32 read_location_last3;
> + __le32 spi_cfg;
> + __le32 num_addr_cycle;
> + __le32 busy_wait_cnt;
> + __le32 flash_feature;
>
> __le32 erased_cw_detect_cfg_clr;
> __le32 erased_cw_detect_cfg_set;
> };
>
> +struct qcom_ecc_stats {
> + u32 corrected;
> + u32 bitflips;
> + u32 failed;
> +};
> +
> +/*
> + * QPIC ECC data struct
> + *
> + */
> +struct qpic_ecc {
> + struct device *dev;
> + const struct qpic_ecc_caps *caps;
> + struct completion done;
> + u32 sectors;
> + u8 *eccdata;
> + bool use_ecc;
> + u32 ecc_modes;
> + int ecc_bytes_hw;
> + int spare_bytes;
> + int bbm_size;
> + int ecc_mode;
> + int bytes;
> + int steps;
> + int step_size;
> + int strength;
> + int cw_size;
> + int cw_data;
> + u32 cfg0, cfg1;
> + u32 cfg0_raw, cfg1_raw;
> + u32 ecc_buf_cfg;
> + u32 ecc_bch_cfg;
> + u32 clrflashstatus;
> + u32 clrreadstatus;
> + bool bch_enabled;
> +};
> +
> +struct qpic_ecc;
> /*
> * NAND controller data struct
> *
> @@ -352,6 +399,7 @@ struct nandc_regs {
> * initialized via DT match data
> *
> * @controller: base controller structure
> + * @ctlr: spi controller structure
> * @host_list: list containing all the chips attached to the
> * controller
> *
> @@ -389,6 +437,7 @@ struct qcom_nand_controller {
>
> struct clk *core_clk;
> struct clk *aon_clk;
> + struct clk *iomacro_clk;
>
> struct nandc_regs *regs;
> struct bam_transaction *bam_txn;
> @@ -396,6 +445,7 @@ struct qcom_nand_controller {
> const struct qcom_nandc_props *props;
>
> struct nand_controller controller;
> + struct spi_controller *ctlr;
> struct list_head host_list;
>
> union {
> @@ -432,6 +482,17 @@ struct qcom_nand_controller {
>
> u32 cmd1, vld;
> bool exec_opwrite;
> + struct qpic_ecc *ecc;
> + struct qcom_ecc_stats ecc_stats;
> + struct nand_ecc_engine ecc_eng;
> + u8 *wbuf;
> + u32 wlen;
> + u32 addr1;
> + u32 addr2;
> + u32 cmd;
> + u32 num_cw;
> + bool oob_read;
> + bool raw;
> };
>
> /*


Thanks,
Miquèl