From c6908077b194e46e7180d241ff2dbb85dc30bbd1 Mon Sep 17 00:00:00 2001 From: Tudor Ambarus Date: Mon, 5 Oct 2020 21:01:31 +0530 Subject: mtd: spi-nor: Introduce SNOR_F_IO_MODE_EN_VOLATILE We don't want to enter a stateful mode, where a X-X-X I/O mode is entered by setting a non-volatile bit, because in case of a reset or a crash, once in the non-volatile mode, we may not be able to recover in bootloaders and we may break the SPI NOR boot. Forbid by default the I/O modes that are set via a non-volatile bit. SPI_NOR_IO_MODE_EN_VOLATILE should be set just for the flashes that don't define the optional SFDP SCCR Map, so that we don't pollute the flash info flags. Signed-off-by: Tudor Ambarus Signed-off-by: Pratyush Yadav Signed-off-by: Vignesh Raghavendra Link: https://lore.kernel.org/r/20201005153138.6437-9-p.yadav@ti.com --- drivers/mtd/spi-nor/core.c | 3 +++ drivers/mtd/spi-nor/core.h | 6 ++++++ 2 files changed, 9 insertions(+) (limited to 'drivers/mtd/spi-nor') diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c index 518d16511dee..45d45b51705e 100644 --- a/drivers/mtd/spi-nor/core.c +++ b/drivers/mtd/spi-nor/core.c @@ -3388,6 +3388,9 @@ int spi_nor_scan(struct spi_nor *nor, const char *name, if (info->flags & SPI_NOR_4B_OPCODES) nor->flags |= SNOR_F_4B_OPCODES; + if (info->flags & SPI_NOR_IO_MODE_EN_VOLATILE) + nor->flags |= SNOR_F_IO_MODE_EN_VOLATILE; + ret = spi_nor_set_addr_width(nor); if (ret) return ret; diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h index 9a33c8d07335..eaece1123c0b 100644 --- a/drivers/mtd/spi-nor/core.h +++ b/drivers/mtd/spi-nor/core.h @@ -26,6 +26,7 @@ enum spi_nor_option_flags { SNOR_F_HAS_SR_TB_BIT6 = BIT(11), SNOR_F_HAS_4BIT_BP = BIT(12), SNOR_F_HAS_SR_BP3_BIT6 = BIT(13), + SNOR_F_IO_MODE_EN_VOLATILE = BIT(14), }; struct spi_nor_read_command { @@ -320,6 +321,11 @@ struct flash_info { */ #define SPI_NOR_OCTAL_DTR_READ BIT(19) /* Flash supports octal DTR Read. */ #define SPI_NOR_OCTAL_DTR_PP BIT(20) /* Flash supports Octal DTR Page Program */ +#define SPI_NOR_IO_MODE_EN_VOLATILE BIT(21) /* + * Flash enables the best + * available I/O mode via a + * volatile bit. + */ /* Part specific fixup hooks. */ const struct spi_nor_fixups *fixups; -- cgit