Re: [PATCH v2 4/9] mtd: rawnand: jz4780: Add support for the JZ4740

Boris Brezillon
2019-02-03T07:32:16Z

On Sat, 2 Feb 2019 20:19:21 -0300
Paul Cercueil <paul@crapouillou.net> wrote:

> Add support for probing the jz4780-nand driver on the JZ4740 SoC from
> Ingenic.
>
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> ---
>
> Changes:
>
> v2: - Add support for the JZ4740 and not the JZ4725B: they behave the
> same, and JZ4740 is fully upstream while JZ4725B is not. The
> JZ4725B devicetree will then simply use the "ingenic,jz4740-nand"
> compatible string.
> - Fix the number of bytes for the ECC when the ECC strength is 4.
> This is needed for the JZ4740, which uses Reed-Solomon instead of
> BCH.
>
> drivers/mtd/nand/raw/ingenic/jz4780_nand.c | 48 +++++++++++++++++-----

If we're going to make the driver compatible with jz4740 and jz4725b
maybe we should rename the source files jz47xx_{nand,bch}.{c,h}.

> 1 file changed, 37 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/mtd/nand/raw/ingenic/jz4780_nand.c b/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
> index 7f55358b860f..c0855fef7735 100644
> --- a/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
> +++ b/drivers/mtd/nand/raw/ingenic/jz4780_nand.c
> @@ -13,6 +13,7 @@
> #include <linux/module.h>
> #include <linux/of.h>
> #include <linux/of_address.h>
> +#include <linux/of_device.h>
> #include <linux/gpio/consumer.h>
> #include <linux/platform_device.h>
> #include <linux/slab.h>
> @@ -26,13 +27,15 @@
>
> #define DRV_NAME "jz4780-nand"
>
> -#define OFFSET_DATA 0x00000000
> -#define OFFSET_CMD 0x00400000
> -#define OFFSET_ADDR 0x00800000
> -
> /* Command delay when there is no R/B pin. */
> #define RB_DELAY_US 100
>
> +struct jz_soc_info {
> + unsigned long data_offset;
> + unsigned long addr_offset;
> + unsigned long cmd_offset;
> +};
> +
> struct jz4780_nand_cs {
> unsigned int bank;
> void __iomem *base;
> @@ -40,6 +43,7 @@ struct jz4780_nand_cs {
>
> struct jz4780_nand_controller {
> struct device *dev;
> + const struct jz_soc_info *soc_info;
> struct jz4780_bch *bch;
> struct nand_controller controller;
> unsigned int num_banks;
> @@ -101,9 +105,9 @@ static void jz4780_nand_cmd_ctrl(struct nand_chip *chip, int cmd,
> return;
>
> if (ctrl & NAND_ALE)
> - writeb(cmd, cs->base + OFFSET_ADDR);
> + writeb(cmd, cs->base + nfc->soc_info->addr_offset);
> else if (ctrl & NAND_CLE)
> - writeb(cmd, cs->base + OFFSET_CMD);
> + writeb(cmd, cs->base + nfc->soc_info->cmd_offset);
> }
>
> static int jz4780_nand_dev_ready(struct nand_chip *chip)
> @@ -161,8 +165,13 @@ static int jz4780_nand_attach_chip(struct nand_chip *chip)
> struct jz4780_nand_controller *nfc = to_jz4780_nand_controller(chip->controller);
> int eccbytes;
>
> - chip->ecc.bytes = fls((1 + 8) * chip->ecc.size) *
> - (chip->ecc.strength / 8);
> + if (chip->ecc.strength == 4) {
> + /* JZ4740 uses 9 bytes of ECC to correct maximum 4 errors */
> + chip->ecc.bytes = 9;
> + } else {
> + chip->ecc.bytes = fls((1 + 8) * chip->ecc.size) *
> + (chip->ecc.strength / 8);
> + }
>
> switch (chip->ecc.mode) {
> case NAND_ECC_HW:
> @@ -272,8 +281,8 @@ static int jz4780_nand_init_chip(struct platform_device *pdev,
> return -ENOMEM;
> mtd->dev.parent = dev;
>
> - chip->legacy.IO_ADDR_R = cs->base + OFFSET_DATA;
> - chip->legacy.IO_ADDR_W = cs->base + OFFSET_DATA;
> + chip->legacy.IO_ADDR_R = cs->base + nfc->soc_info->data_offset;
> + chip->legacy.IO_ADDR_W = cs->base + nfc->soc_info->data_offset;
> chip->legacy.chip_delay = RB_DELAY_US;
> chip->options = NAND_NO_SUBPAGE_WRITE;
> chip->legacy.select_chip = jz4780_nand_select_chip;
> @@ -353,6 +362,10 @@ static int jz4780_nand_probe(struct platform_device *pdev)
> if (!nfc)
> return -ENOMEM;
>
> + nfc->soc_info = device_get_match_data(dev);
> + if (!nfc->soc_info)
> + return -EINVAL;
> +
> /*
> * Check for BCH HW before we call nand_scan_ident, to prevent us from
> * having to call it again if the BCH driver returns -EPROBE_DEFER.
> @@ -390,8 +403,21 @@ static int jz4780_nand_remove(struct platform_device *pdev)
> return 0;
> }
>
> +static const struct jz_soc_info jz4740_soc_info = {
> + .data_offset = 0x00000000,
> + .cmd_offset = 0x00008000,
> + .addr_offset = 0x00010000,
> +};
> +
> +static const struct jz_soc_info jz4780_soc_info = {
> + .data_offset = 0x00000000,
> + .cmd_offset = 0x00400000,
> + .addr_offset = 0x00800000,
> +};
> +
> static const struct of_device_id jz4780_nand_dt_match[] = {
> - { .compatible = "ingenic,jz4780-nand" },
> + { .compatible = "ingenic,jz4740-nand", .data = &jz4740_soc_info },
> + { .compatible = "ingenic,jz4780-nand", .data = &jz4780_soc_info },
> {},
> };
> MODULE_DEVICE_TABLE(of, jz4780_nand_dt_match);