diff options
Diffstat (limited to 'target/linux/generic/pending-5.4/470-mtd-spi-nor-support-limiting-4K-sectors-support-base.patch')
| -rw-r--r-- | target/linux/generic/pending-5.4/470-mtd-spi-nor-support-limiting-4K-sectors-support-base.patch | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/target/linux/generic/pending-5.4/470-mtd-spi-nor-support-limiting-4K-sectors-support-base.patch b/target/linux/generic/pending-5.4/470-mtd-spi-nor-support-limiting-4K-sectors-support-base.patch new file mode 100644 index 0000000000..12d785856a --- /dev/null +++ b/target/linux/generic/pending-5.4/470-mtd-spi-nor-support-limiting-4K-sectors-support-base.patch @@ -0,0 +1,56 @@ +From: Felix Fietkau <nbd@nbd.name> +Date: Sat, 4 Nov 2017 07:40:23 +0100 +Subject: [PATCH] mtd: spi-nor: support limiting 4K sectors support based on + flash size + +Some devices need 4K sectors to be able to deal with small flash chips. +For instance, w25x05 is 64 KiB in size, and without 4K sectors, the +entire chip is just one erase block. +On bigger flash chip sizes, using 4K sectors can significantly slow down +many operations, including using a writable filesystem. There are several +platforms where it makes sense to use a single kernel on both kinds of +devices. + +To support this properly, allow configuring an upper flash chip size +limit for 4K sectors support. + +Signed-off-by: Felix Fietkau <nbd@nbd.name> +--- + +--- a/drivers/mtd/spi-nor/Kconfig ++++ b/drivers/mtd/spi-nor/Kconfig +@@ -39,6 +39,17 @@ config SPI_ASPEED_SMC + and support for the SPI flash memory controller (SPI) for + the host firmware. The implementation only supports SPI NOR. + ++config MTD_SPI_NOR_USE_4K_SECTORS_LIMIT ++ int "Maximum flash chip size to use 4K sectors on (in KiB)" ++ depends on MTD_SPI_NOR_USE_4K_SECTORS ++ default "4096" ++ help ++ There are many flash chips that support 4K sectors, but are so large ++ that using them significantly slows down writing large amounts of ++ data or using a writable filesystem. ++ Any flash chip larger than the size specified in this option will ++ not use 4K sectors. ++ + config SPI_ATMEL_QUADSPI + tristate "Atmel Quad SPI Controller" + depends on ARCH_AT91 || (ARM && COMPILE_TEST && !ARCH_EBSA110) +--- a/drivers/mtd/spi-nor/spi-nor.c ++++ b/drivers/mtd/spi-nor/spi-nor.c +@@ -2649,10 +2649,12 @@ static int spi_nor_select_erase(struct s + + #ifdef CONFIG_MTD_SPI_NOR_USE_4K_SECTORS + /* prefer "small sector" erase if possible */ +- if (info->flags & SECT_4K) { ++ if ((info->flags & SECT_4K) && (mtd->size <= ++ CONFIG_MTD_SPI_NOR_USE_4K_SECTORS_LIMIT * 1024)) { + nor->erase_opcode = SPINOR_OP_BE_4K; + mtd->erasesize = 4096; +- } else if (info->flags & SECT_4K_PMC) { ++ } else if ((info->flags & SECT_4K_PMC) && (mtd->size <= ++ CONFIG_MTD_SPI_NOR_USE_4K_SECTORS_LIMIT * 1024)) { + nor->erase_opcode = SPINOR_OP_BE_4K_PMC; + mtd->erasesize = 4096; + } else |