diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 73172d7f512b..0c2ec1c21434 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -1636,6 +1636,95 @@ static int sr2_bit7_quad_enable(struct spi_nor *nor) return 0; } +/** + * spi_nor_clear_sr_bp() - clear the Status Register Block Protection bits. + * @nor: pointer to a 'struct spi_nor' + * + * Read-modify-write function that clears the Block Protection bits from the + * Status Register without affecting other bits. + * + * Return: 0 on success, -errno otherwise. + */ +static int spi_nor_clear_sr_bp(struct spi_nor *nor) +{ + int ret; + u8 mask = SR_BP2 | SR_BP1 | SR_BP0; + + ret = read_sr(nor); + if (ret < 0) { + dev_err(nor->dev, "error while reading status register\n"); + return ret; + } + + write_enable(nor); + + ret = write_sr(nor, ret & ~mask); + if (ret) { + dev_err(nor->dev, "write to status register failed\n"); + return ret; + } + + ret = spi_nor_wait_till_ready(nor); + if (ret) + dev_err(nor->dev, "timeout while writing status register\n"); + return ret; +} + +/** + * spi_nor_spansion_clear_sr_bp() - clear the Status Register Block Protection + * bits on spansion flashes. + * @nor: pointer to a 'struct spi_nor' + * + * Read-modify-write function that clears the Block Protection bits from the + * Status Register without affecting other bits. The function is tightly + * coupled with the spansion_quad_enable() function. Both assume that the Write + * Register with 16 bits, together with the Read Configuration Register (35h) + * instructions are supported. + * + * Return: 0 on success, -errno otherwise. + */ +static int spi_nor_spansion_clear_sr_bp(struct spi_nor *nor) +{ + int ret; + u8 mask = SR_BP2 | SR_BP1 | SR_BP0; + u8 sr_cr[2] = {0}; + + /* Check current Quad Enable bit value. */ + ret = read_cr(nor); + if (ret < 0) { + dev_err(nor->dev, + "error while reading configuration register\n"); + return ret; + } + + /* + * When the configuration register Quad Enable bit is one, only the + * Write Status (01h) command with two data bytes may be used. + */ + if (ret & CR_QUAD_EN_SPAN) { + sr_cr[1] = ret; + + ret = read_sr(nor); + if (ret < 0) { + dev_err(nor->dev, + "error while reading status register\n"); + return ret; + } + sr_cr[0] = ret & ~mask; + + ret = write_sr_cr(nor, sr_cr); + if (ret) + dev_err(nor->dev, "16-bit write register failed\n"); + return ret; + } + + /* + * If the Quad Enable bit is zero, use the Write Status (01h) command + * with one data byte. + */ + return spi_nor_clear_sr_bp(nor); +} + /* Used when the "_ext_id" is two bytes at most */ #define INFO(_jedec_id, _ext_id, _sector_size, _n_sectors, _flags) \ .id = { \ @@ -3660,6 +3749,8 @@ static int spi_nor_init_params(struct spi_nor *nor, default: /* Kept only for backward compatibility purpose. */ params->quad_enable = spansion_quad_enable; + if (nor->clear_sr_bp) + nor->clear_sr_bp = spi_nor_spansion_clear_sr_bp; break; } @@ -3912,17 +4003,13 @@ static int spi_nor_init(struct spi_nor *nor) { int err; - /* - * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up - * with the software protection bits set - */ - if (JEDEC_MFR(nor->info) == SNOR_MFR_ATMEL || - JEDEC_MFR(nor->info) == SNOR_MFR_INTEL || - JEDEC_MFR(nor->info) == SNOR_MFR_SST || - nor->info->flags & SPI_NOR_HAS_LOCK) { - write_enable(nor); - write_sr(nor, 0); - spi_nor_wait_till_ready(nor); + if (nor->clear_sr_bp) { + err = nor->clear_sr_bp(nor); + if (err) { + dev_err(nor->dev, + "fail to clear block protection bits\n"); + return err; + } } if (nor->quad_enable) { @@ -4047,6 +4134,16 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, if (info->flags & SPI_S3AN) nor->flags |= SNOR_F_READY_XSR_RDY; + /* + * Atmel, SST, Intel/Numonyx, and others serial NOR tend to power up + * with the software protection bits set. + */ + if (JEDEC_MFR(nor->info) == SNOR_MFR_ATMEL || + JEDEC_MFR(nor->info) == SNOR_MFR_INTEL || + JEDEC_MFR(nor->info) == SNOR_MFR_SST || + nor->info->flags & SPI_NOR_HAS_LOCK) + nor->clear_sr_bp = spi_nor_clear_sr_bp; + /* Parse the Serial Flash Discoverable Parameters table. */ ret = spi_nor_init_params(nor, ¶ms); if (ret) diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index b3d360b0ee3d..9f57cdfcc93d 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -373,6 +373,8 @@ struct flash_info; * @flash_unlock: [FLASH-SPECIFIC] unlock a region of the SPI NOR * @flash_is_locked: [FLASH-SPECIFIC] check if a region of the SPI NOR is * @quad_enable: [FLASH-SPECIFIC] enables SPI NOR quad mode + * @clear_sr_bp: [FLASH-SPECIFIC] clears the Block Protection Bits from + * the SPI NOR Status Register. * completely locked * @priv: the private data */ @@ -410,6 +412,7 @@ struct spi_nor { int (*flash_unlock)(struct spi_nor *nor, loff_t ofs, uint64_t len); int (*flash_is_locked)(struct spi_nor *nor, loff_t ofs, uint64_t len); int (*quad_enable)(struct spi_nor *nor); + int (*clear_sr_bp)(struct spi_nor *nor); void *priv; };