Re: [PATCH 1/3] mtd: spi-nor: add Global Block Unlock support

From: Cyrille Pitchen
Date: Wed Jul 25 2018 - 08:26:43 EST


Hi Tudor,

Le 17/07/2018 Ã 18:28, Tudor Ambarus a ÃcritÂ:
> We can't determine this purely by manufacturer type and it's not
> autodetectable by anything like SFDP, so make a new flag for it:
> UNLOCK_GLOBAL_BLOCK.
>
> Note that the Global Block Unlock command has different names
> depending on the manufacturer, but always the same command value:
> 0x98. Macronix's MX25U12835F names it Gang Block Unlock,
> Winbound's W25Q128FV names it Global Block Unlock and
> Microchip's SST26VF064B names it Global Block Protection Unlock.
>
> Based on initial work done by Anurag Kumar Vulisha:
> https://patchwork.kernel.org/patch/7611271/
>
> Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>

Reviewed-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxxxxxx>

Best regards,

Cyrille
> ---
> drivers/mtd/spi-nor/spi-nor.c | 21 +++++++++++++++++++++
> include/linux/mtd/spi-nor.h | 1 +
> 2 files changed, 22 insertions(+)
>
> diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c
> index d9c368c..6648251 100644
> --- a/drivers/mtd/spi-nor/spi-nor.c
> +++ b/drivers/mtd/spi-nor/spi-nor.c
> @@ -89,6 +89,7 @@ struct flash_info {
> #define NO_CHIP_ERASE BIT(12) /* Chip does not support chip erase */
> #define SPI_NOR_SKIP_SFDP BIT(13) /* Skip parsing of SFDP tables */
> #define USE_CLSR BIT(14) /* use CLSR command */
> +#define UNLOCK_GLOBAL_BLOCK BIT(15) /* Unlock global block protection */
>
> int (*quad_enable)(struct spi_nor *nor);
> };
> @@ -2730,6 +2731,17 @@ static int spi_nor_setup(struct spi_nor *nor, const struct flash_info *info,
> return 0;
> }
>
> +static int spi_nor_unlock_global_block_protection(struct spi_nor *nor)
> +{
> + int ret;
> +
> + write_enable(nor);
> + ret = nor->write_reg(nor, SPINOR_OP_GBULK, NULL, 0);
> + if (ret < 0)
> + return ret;
> + return spi_nor_wait_till_ready(nor);
> +}
> +
> static int spi_nor_init(struct spi_nor *nor)
> {
> int err;
> @@ -2747,6 +2759,15 @@ static int spi_nor_init(struct spi_nor *nor)
> spi_nor_wait_till_ready(nor);
> }
>
> + if (nor->info->flags & UNLOCK_GLOBAL_BLOCK) {
> + err = spi_nor_unlock_global_block_protection(nor);
> + if (err) {
> + dev_err(nor->dev,
> + "Cannot unlock the global block protection\n");
> + return err;
> + }
> + }
> +
> if (nor->quad_enable) {
> err = nor->quad_enable(nor);
> if (err) {
> diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h
> index e60da0d..e8dd11d 100644
> --- a/include/linux/mtd/spi-nor.h
> +++ b/include/linux/mtd/spi-nor.h
> @@ -64,6 +64,7 @@
> #define SPINOR_OP_CLFSR 0x50 /* Clear flag status register */
> #define SPINOR_OP_RDEAR 0xc8 /* Read Extended Address Register */
> #define SPINOR_OP_WREAR 0xc5 /* Write Extended Address Register */
> +#define SPINOR_OP_GBULK 0x98 /* Global Block Unlock Protection */
>
> /* 4-byte address opcodes - used on Spansion and some Macronix flashes. */
> #define SPINOR_OP_READ_4B 0x13 /* Read data bytes (low frequency) */
>