Re: [PATCH V3] mtd: rawnand: qcom: avoid writing to obsolete register

From: Miquel Raynal
Date: Mon Jun 07 2021 - 05:50:46 EST


Hello,

Md Sadre Alam <mdalam@xxxxxxxxxxxxxx> wrote on Mon, 7 Jun 2021
15:13:37 +0530:

> QPIC_EBI2_ECC_BUF_CFG register got obsolete from QPIC V2.0 onwards.
> Avoid writing this register if QPIC version is V2.0 or newer.
>
> Also fixed nandc undeclared issue reported by,
>
> Reported-by: kernel test robot <lkp@xxxxxxxxx>

This tag should only be added when you fix something that is already in
mainline. The Reported-by here points to v2, which makes no sense.
Please drop it.

> Signed-off-by: Md Sadre Alam <mdalam@xxxxxxxxxxxxxx>
> ---
> [V3]
> * Fixed nandc undeclared issue.
> drivers/mtd/nand/raw/qcom_nandc.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/qcom_nandc.c b/drivers/mtd/nand/raw/qcom_nandc.c
> index a64fb6c..ee5985d 100644
> --- a/drivers/mtd/nand/raw/qcom_nandc.c
> +++ b/drivers/mtd/nand/raw/qcom_nandc.c
> @@ -734,6 +734,7 @@ static void update_rw_regs(struct qcom_nand_host *host, int num_cw, bool read, i
> {
> struct nand_chip *chip = &host->chip;
> u32 cmd, cfg0, cfg1, ecc_bch_cfg;
> + struct qcom_nand_controller *nandc = get_qcom_nand_controller(chip);
>
> if (read) {
> if (host->use_ecc)
> @@ -762,7 +763,8 @@ static void update_rw_regs(struct qcom_nand_host *host, int num_cw, bool read, i
> nandc_set_reg(chip, NAND_DEV0_CFG0, cfg0);
> nandc_set_reg(chip, NAND_DEV0_CFG1, cfg1);
> nandc_set_reg(chip, NAND_DEV0_ECC_CFG, ecc_bch_cfg);
> - nandc_set_reg(chip, NAND_EBI2_ECC_BUF_CFG, host->ecc_buf_cfg);
> + if (!nandc->props->qpic_v2)
> + nandc_set_reg(chip, NAND_EBI2_ECC_BUF_CFG, host->ecc_buf_cfg);
> nandc_set_reg(chip, NAND_FLASH_STATUS, host->clrflashstatus);
> nandc_set_reg(chip, NAND_READ_STATUS, host->clrreadstatus);
> nandc_set_reg(chip, NAND_EXEC_CMD, 1);
> @@ -1133,7 +1135,8 @@ static void config_nand_page_read(struct nand_chip *chip)
>
> write_reg_dma(nandc, NAND_ADDR0, 2, 0);
> write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0);
> - write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1, 0);
> + if (!nandc->props->qpic_v2)
> + write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1, 0);
> write_reg_dma(nandc, NAND_ERASED_CW_DETECT_CFG, 1, 0);
> write_reg_dma(nandc, NAND_ERASED_CW_DETECT_CFG, 1,
> NAND_ERASED_CW_SET | NAND_BAM_NEXT_SGL);
> @@ -1191,8 +1194,9 @@ static void config_nand_page_write(struct nand_chip *chip)
>
> write_reg_dma(nandc, NAND_ADDR0, 2, 0);
> write_reg_dma(nandc, NAND_DEV0_CFG0, 3, 0);
> - write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1,
> - NAND_BAM_NEXT_SGL);
> + if (!nandc->props->qpic_v2)
> + write_reg_dma(nandc, NAND_EBI2_ECC_BUF_CFG, 1,
> + NAND_BAM_NEXT_SGL);
> }
>
> /*
> @@ -1248,7 +1252,8 @@ static int nandc_param(struct qcom_nand_host *host)
> | 2 << WR_RD_BSY_GAP
> | 0 << WIDE_FLASH
> | 1 << DEV0_CFG1_ECC_DISABLE);
> - nandc_set_reg(chip, NAND_EBI2_ECC_BUF_CFG, 1 << ECC_CFG_ECC_DISABLE);
> + if (!nandc->props->qpic_v2)
> + nandc_set_reg(chip, NAND_EBI2_ECC_BUF_CFG, 1 << ECC_CFG_ECC_DISABLE);
>
> /* configure CMD1 and VLD for ONFI param probing in QPIC v1 */
> if (!nandc->props->qpic_v2) {
> @@ -2689,7 +2694,8 @@ static int qcom_nand_attach_chip(struct nand_chip *chip)
> | ecc_mode << ECC_MODE
> | host->ecc_bytes_hw << ECC_PARITY_SIZE_BYTES_BCH;
>
> - host->ecc_buf_cfg = 0x203 << NUM_STEPS;
> + if (!nandc->props->qpic_v2)
> + host->ecc_buf_cfg = 0x203 << NUM_STEPS;
>
> host->clrflashstatus = FS_READY_BSY_N;
> host->clrreadstatus = 0xc0;


Thanks,
Miquèl