From 5d867bcc2321041445ebb60d437b818bf706162f Mon Sep 17 00:00:00 2001 From: Michael Walle Date: Wed, 9 Dec 2020 10:53:25 +0100 Subject: [PATCH] mtd: spi-nor: add unlock all config option Provide an explicit configuration option to disable default "unlock all" of any flash chip which supports locking. It doesn't make sense to automatically unprotect the entire flash on each u-boot startup if the block protection bits are actually used. Traditionally, the unlock was there to be able to write to flash devices which powered-up with the block protection bits set. Over time this feature creeped into all flash devices which support locking. For a more detailed description and discussion see: https://lore.kernel.org/linux-mtd/20201203162959.29589-8-michael@walle.cc/ Keep things simple in u-boot and just provide a configration option to disable this behavior which can be set per board. Signed-off-by: Michael Walle Reviewed-by: Priyanka Jain --- drivers/mtd/spi/Kconfig | 10 ++++++++++ drivers/mtd/spi/spi-nor-core.c | 9 +++++---- 2 files changed, 15 insertions(+), 4 deletions(-) diff --git a/drivers/mtd/spi/Kconfig b/drivers/mtd/spi/Kconfig index ea444436ad..f8db8e5213 100644 --- a/drivers/mtd/spi/Kconfig +++ b/drivers/mtd/spi/Kconfig @@ -95,6 +95,16 @@ config SPI_FLASH_BAR Bank/Extended address registers are used to access the flash which has size > 16MiB in 3-byte addressing. +config SPI_FLASH_UNLOCK_ALL + bool "Unlock the entire SPI flash on u-boot startup" + default y + help + Some flashes tend to power up with the software write protection + bits set. If this option is set, the whole flash will be unlocked. + + For legacy reasons, this option default to y. But if you intend to + actually use the software protection bits you should say n here. + config SF_DUAL_FLASH bool "SPI DUAL flash memory support" help diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index e16b0e1462..ef426dac02 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -2443,10 +2443,11 @@ static int spi_nor_init(struct spi_nor *nor) * 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) { + if (IS_ENABLED(CONFIG_SPI_FLASH_UNLOCK_ALL) && + (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); -- 2.39.5