Re: [PATCH] spi-nor: Add support for xt25f128b

[<Tudor.Ambarus@microchip.com>]

Hi, Andreas,

On 12/21/20 12:43 AM, Andreas Rammhold wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> This adds support for the xt25f128b as found on the rockpi4b SBC.
> 
> Signed-off-by: Andreas Rammhold <andreas@rammhold.de>
> ---
> 
> This continues the efforts done in [1] & [2] that went stale. I've
> tested this patch on my RockPi4b which only has the xt25f128b (and not
> the xt25f32b as also propsed in [2]). I have tried to obtain a copy of
> the datasheets but was unable to find them. Not sure whre you would get
> them.
> 
> While [1] was already for the new spi-nor layout it was missing the bits
> in the core.{c,h} files.
> 
> 
> [1]: https://patchwork.ozlabs.org/project/linux-mtd/patch/CAMgqO2y9MYDj6antOaWLBRKU8vGEwqCB-Y1TkXTSWsmsed+W6A@mail.gmail.com/
> [2]: https://patchwork.ozlabs.org/project/linux-mtd/patch/20200206171941.GA2398@makrotopia.org/
> 
>  drivers/mtd/spi-nor/Makefile |  1 +
>  drivers/mtd/spi-nor/core.c   |  1 +
>  drivers/mtd/spi-nor/core.h   |  1 +
>  drivers/mtd/spi-nor/xtx.c    | 16 ++++++++++++++++
>  4 files changed, 19 insertions(+)
>  create mode 100644 drivers/mtd/spi-nor/xtx.c
> 
> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> index 653923896205..3f7a52d7fa0b 100644
> --- a/drivers/mtd/spi-nor/Makefile
> +++ b/drivers/mtd/spi-nor/Makefile
> @@ -17,6 +17,7 @@ spi-nor-objs                  += sst.o
>  spi-nor-objs                   += winbond.o
>  spi-nor-objs                   += xilinx.o
>  spi-nor-objs                   += xmc.o
> +spi-nor-objs                   += xtx.o
>  obj-$(CONFIG_MTD_SPI_NOR)      += spi-nor.o
> 
>  obj-$(CONFIG_MTD_SPI_NOR)      += controllers/
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index f0ae7a01703a..ca1988554945 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -2024,6 +2024,7 @@ static const struct spi_nor_manufacturer *manufacturers[] = {
>         &spi_nor_winbond,
>         &spi_nor_xilinx,
>         &spi_nor_xmc,
> +       &spi_nor_xtx,
>  };
> 
>  static const struct flash_info *
> diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
> index 6f2f6b27173f..cea8c0c25c9f 100644
> --- a/drivers/mtd/spi-nor/core.h
> +++ b/drivers/mtd/spi-nor/core.h
> @@ -398,6 +398,7 @@ extern const struct spi_nor_manufacturer spi_nor_sst;
>  extern const struct spi_nor_manufacturer spi_nor_winbond;
>  extern const struct spi_nor_manufacturer spi_nor_xilinx;
>  extern const struct spi_nor_manufacturer spi_nor_xmc;
> +extern const struct spi_nor_manufacturer spi_nor_xtx;
> 
>  int spi_nor_write_enable(struct spi_nor *nor);
>  int spi_nor_write_disable(struct spi_nor *nor);
> diff --git a/drivers/mtd/spi-nor/xtx.c b/drivers/mtd/spi-nor/xtx.c
> new file mode 100644
> index 000000000000..a10102d8b3e2
> --- /dev/null
> +++ b/drivers/mtd/spi-nor/xtx.c
> @@ -0,0 +1,16 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/mtd/spi-nor.h>
> +
> +#include "core.h"
> +
> +static const struct flash_info xtx_parts[] = {
> + /* XTX (Shenzhen Xin Tian Xia Tech) */
> + { "xt25f128b", INFO(0x0b4018, 0, 64 * 1024, 256, SECT_4K) },

According to JEP106BA, the XTX's identification code is in bank 10
and is comprised of 9 Continuation Codes (0x7f) and then by 0B.
XTX's manufacturer ID should be:
0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x0b.

Can you hack the SPI_NOR_MAX_ID_LEN field, in order to read 12
or more bytes? I assume XTX got it wrong, and put the
continuation codes after the flash ID.

Cheers,
ta

> +};
> +
> +const struct spi_nor_manufacturer spi_nor_xtx = {
> + .name = "xtx",
> + .parts = xtx_parts,
> + .nparts = ARRAY_SIZE(xtx_parts),
> +};
> --
> 2.29.2
>