On modern NAND it's more than recommended to have a backup copy of the u-boot binary to recover from corruption: bitflips are quite common on MLC NANDs, and the read-disturbance will corrupt your u-boot partitition more quickly than what you would see on an SLC NAND.
Add an extra Kconfig option to specify the offset of the redundant u-boot image.
Signed-off-by: Boris Brezillon boris.brezillon@free-electrons.com --- common/spl/spl_nand.c | 8 ++++++++ drivers/mtd/nand/Kconfig | 6 ++++++ 2 files changed, 14 insertions(+)
diff --git a/common/spl/spl_nand.c b/common/spl/spl_nand.c index 612bd4a..0bf0848 100644 --- a/common/spl/spl_nand.c +++ b/common/spl/spl_nand.c @@ -12,6 +12,9 @@
#ifndef CONFIG_SYS_NAND_U_BOOT_OFFS #define CONFIG_SYS_NAND_U_BOOT_OFFS CONFIG_SPL_NAND_U_BOOT_OFFS +#define CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND CONFIG_SPL_NAND_U_BOOT_OFFS_REDUND +#else +#define CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND CONFIG_SYS_NAND_U_BOOT_OFFS #endif
#if defined(CONFIG_SPL_NAND_RAW_ONLY) @@ -111,6 +114,11 @@ int spl_nand_load_image(void) #endif /* Load u-boot */ err = spl_nand_load_element(CONFIG_SYS_NAND_U_BOOT_OFFS, header); +#if CONFIG_SYS_NAND_U_BOOT_OFFS != CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND + if (err) + err = spl_nand_load_element(CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND, + header); +#endif nand_deselect(); return err; } diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig index 4b0f92c..2f1d1f7 100644 --- a/drivers/mtd/nand/Kconfig +++ b/drivers/mtd/nand/Kconfig @@ -110,6 +110,12 @@ config SPL_NAND_U_BOOT_OFFS Set the offset from the start of the nand where u-boot should be loaded from.
+config SPL_NAND_U_BOOT_OFFS_REDUND + hex "Location in NAND to read U-Boot from" + default SPL_NAND_U_BOOT_OFFS + help + Set the offset from the start of the nand where u-boot should be + loaded from.
config SPL_NAND_DENALI bool "Support Denali NAND controller for SPL"