From 05635c14a292de0e1a221dc31c04aba3913f03c8 Mon Sep 17 00:00:00 2001 From: Jungseung Lee Date: Wed, 18 Mar 2020 21:06:14 +0900 Subject: [PATCH] mtd: spi-nor: Add SR 4bit block protection support Currently we are supporting block protection only for flash chips with 3 block protection bits (BP0-2) in the SR register. Enable block protection support for flashes with 4 block protection bits (BP0-3). Add a flash_info flag for flashes that describe 4 block protection bits. Add another flash_info flag for flashes in which BP3 bit is not adjacent to the BP0-2 bits. Tested with a n25q512ax3 (BP0-3) and w25q128 (BP0-2). Signed-off-by: Jungseung Lee Reviewed-by: Michael Walle Tested-by: Michael Walle Signed-off-by: Tudor Ambarus --- drivers/mtd/spi-nor/core.c | 66 +++++++++++++++++++++++++++---------- drivers/mtd/spi-nor/core.h | 10 ++++++ include/linux/mtd/spi-nor.h | 2 ++ 3 files changed, 60 insertions(+), 18 deletions(-) diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index 8146d82afe61..cc68ea84318e 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -1536,13 +1536,34 @@ static int spi_nor_erase(struct mtd_info *mtd, struct erase_info *instr) return ret; } +static u8 spi_nor_get_sr_bp_mask(struct spi_nor *nor) +{ + u8 mask = SR_BP2 | SR_BP1 | SR_BP0; + + if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6) + return mask | SR_BP3_BIT6; + + if (nor->flags & SNOR_F_HAS_4BIT_BP) + return mask | SR_BP3; + + return mask; +} + +static u8 spi_nor_get_sr_tb_mask(struct spi_nor *nor) +{ + if (nor->flags & SNOR_F_HAS_SR_TB_BIT6) + return SR_TB_BIT6; + else + return SR_TB_BIT5; +} + static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor) { unsigned int bp_slots, bp_slots_needed; - u8 mask = SR_BP2 | SR_BP1 | SR_BP0; + u8 mask = spi_nor_get_sr_bp_mask(nor); /* Reserved one for "protect none" and one for "protect all". */ - bp_slots = (mask >> SR_BP_SHIFT) + 1 - 2; + bp_slots = (1 << hweight8(mask)) - 2; bp_slots_needed = ilog2(nor->info->n_sectors); if (bp_slots_needed > bp_slots) @@ -1557,12 +1578,14 @@ static void spi_nor_get_locked_range_sr(struct spi_nor *nor, u8 sr, loff_t *ofs, { struct mtd_info *mtd = &nor->mtd; u64 min_prot_len; - u8 mask = SR_BP2 | SR_BP1 | SR_BP0; - u8 tb_mask = SR_TB_BIT5; - u8 bp = (sr & mask) >> SR_BP_SHIFT; + u8 mask = spi_nor_get_sr_bp_mask(nor); + u8 tb_mask = spi_nor_get_sr_tb_mask(nor); + u8 bp, val = sr & mask; - if (nor->flags & SNOR_F_HAS_SR_TB_BIT6) - tb_mask = SR_TB_BIT6; + if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3_BIT6) + val = (val & ~SR_BP3_BIT6) | SR_BP3; + + bp = val >> SR_BP_SHIFT; if (!bp) { /* No protection */ @@ -1620,7 +1643,8 @@ static int spi_nor_is_unlocked_sr(struct spi_nor *nor, loff_t ofs, uint64_t len, /* * Lock a region of the flash. Compatible with ST Micro and similar flash. - * Supports the block protection bits BP{0,1,2} in the status register + * Supports the block protection bits BP{0,1,2}/BP{0,1,2,3} in the status + * register * (SR). Does not support these features found in newer SR bitfields: * - SEC: sector/block protect - only handle SEC=0 (block protect) * - CMP: complement protect - only support CMP=0 (range is not complemented) @@ -1655,8 +1679,8 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) struct mtd_info *mtd = &nor->mtd; u64 min_prot_len; int ret, status_old, status_new; - u8 mask = SR_BP2 | SR_BP1 | SR_BP0; - u8 tb_mask = SR_TB_BIT5; + u8 mask = spi_nor_get_sr_bp_mask(nor); + u8 tb_mask = spi_nor_get_sr_tb_mask(nor); u8 pow, val; loff_t lock_len; bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB; @@ -1693,9 +1717,6 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) else lock_len = ofs + len; - if (nor->flags & SNOR_F_HAS_SR_TB_BIT6) - tb_mask = SR_TB_BIT6; - if (lock_len == mtd->size) { val = mask; } else { @@ -1703,6 +1724,9 @@ static int spi_nor_sr_lock(struct spi_nor *nor, loff_t ofs, uint64_t len) pow = ilog2(lock_len) - ilog2(min_prot_len) + 1; val = pow << SR_BP_SHIFT; + if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3) + val = (val & ~SR_BP3) | SR_BP3_BIT6; + if (val & ~mask) return -EINVAL; @@ -1740,8 +1764,8 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) struct mtd_info *mtd = &nor->mtd; u64 min_prot_len; int ret, status_old, status_new; - u8 mask = SR_BP2 | SR_BP1 | SR_BP0; - u8 tb_mask = SR_TB_BIT5; + u8 mask = spi_nor_get_sr_bp_mask(nor); + u8 tb_mask = spi_nor_get_sr_tb_mask(nor); u8 pow, val; loff_t lock_len; bool can_be_top = true, can_be_bottom = nor->flags & SNOR_F_HAS_SR_TB; @@ -1778,9 +1802,6 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) else lock_len = ofs; - if (nor->flags & SNOR_F_HAS_SR_TB_BIT6) - tb_mask = SR_TB_BIT6; - if (lock_len == 0) { val = 0; /* fully unlocked */ } else { @@ -1788,6 +1809,9 @@ static int spi_nor_sr_unlock(struct spi_nor *nor, loff_t ofs, uint64_t len) pow = ilog2(lock_len) - ilog2(min_prot_len) + 1; val = pow << SR_BP_SHIFT; + if (nor->flags & SNOR_F_HAS_SR_BP3_BIT6 && val & SR_BP3) + val = (val & ~SR_BP3) | SR_BP3_BIT6; + /* Some power-of-two sizes are not supported */ if (val & ~mask) return -EINVAL; @@ -3147,6 +3171,12 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, if (info->flags & USE_CLSR) nor->flags |= SNOR_F_USE_CLSR; + if (info->flags & SPI_NOR_4BIT_BP) { + nor->flags |= SNOR_F_HAS_4BIT_BP; + if (info->flags & SPI_NOR_BP3_SR_BIT6) + nor->flags |= SNOR_F_HAS_SR_BP3_BIT6; + } + if (info->flags & SPI_NOR_NO_ERASE) mtd->flags |= MTD_NO_ERASE; diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h index 3ce826b35ad1..6f2f6b27173f 100644 --- a/drivers/mtd/spi-nor/core.h +++ b/drivers/mtd/spi-nor/core.h @@ -24,6 +24,8 @@ enum spi_nor_option_flags { SNOR_F_HAS_16BIT_SR = BIT(9), SNOR_F_NO_READ_CR = BIT(10), SNOR_F_HAS_SR_TB_BIT6 = BIT(11), + SNOR_F_HAS_4BIT_BP = BIT(12), + SNOR_F_HAS_SR_BP3_BIT6 = BIT(13), }; struct spi_nor_read_command { @@ -301,6 +303,14 @@ struct flash_info { * status register. Must be used with * SPI_NOR_HAS_TB. */ +#define SPI_NOR_4BIT_BP BIT(17) /* + * Flash SR has 4 bit fields (BP0-3) + * for block protection. + */ +#define SPI_NOR_BP3_SR_BIT6 BIT(18) /* + * BP3 is bit 6 of status register. + * Must be used with SPI_NOR_4BIT_BP. + */ /* Part specific fixup hooks. */ const struct spi_nor_fixups *fixups; diff --git a/include/linux/mtd/spi-nor.h b/include/linux/mtd/spi-nor.h index e656858b50a5..1e2af0ec1f03 100644 --- a/include/linux/mtd/spi-nor.h +++ b/include/linux/mtd/spi-nor.h @@ -111,7 +111,9 @@ #define SR_BP0 BIT(2) /* Block protect 0 */ #define SR_BP1 BIT(3) /* Block protect 1 */ #define SR_BP2 BIT(4) /* Block protect 2 */ +#define SR_BP3 BIT(5) /* Block protect 3 */ #define SR_TB_BIT5 BIT(5) /* Top/Bottom protect */ +#define SR_BP3_BIT6 BIT(6) /* Block protect 3 */ #define SR_TB_BIT6 BIT(6) /* Top/Bottom protect */ #define SR_SRWD BIT(7) /* SR write protect */ /* Spansion/Cypress specific status bits */