u-boot/drivers/mtd/nand/Kconfig

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menu "NAND Device Support"
config SYS_NAND_SELF_INIT
bool
help
This option, if enabled, provides more flexible and linux-like
NAND initialization process.
config NAND_DENALI
bool "Support Denali NAND controller"
select SYS_NAND_SELF_INIT
help
Enable support for the Denali NAND controller.
config SYS_NAND_DENALI_64BIT
bool "Use 64-bit variant of Denali NAND controller"
depends on NAND_DENALI
help
The Denali NAND controller IP has some variations in terms of
the bus interface. The DMA setup sequence is completely differenct
between 32bit / 64bit AXI bus variants.
If your Denali NAND controller is the 64-bit variant, say Y.
Otherwise (32 bit), say N.
config NAND_DENALI_SPARE_AREA_SKIP_BYTES
int "Number of bytes skipped in OOB area"
depends on NAND_DENALI
range 0 63
help
This option specifies the number of bytes to skip from the beginning
of OOB area before last ECC sector data starts. This is potentially
used to preserve the bad block marker in the OOB area.
kconfig: switch to single .config configuration When Kconfig for U-boot was examined, one of the biggest issues was how to support multiple images (Normal, SPL, TPL). There were actually two options, "single .config" and "multiple .config". After some discussions and thought experiments, I chose the latter, i.e. to create ".config", "spl/.config", "tpl/.config" for Normal, SPL, TPL, respectively. It is true that the "multiple .config" strategy provided us the maximum flexibility and helped to avoid duplicating CONFIGs among Normal, SPL, TPL, but I have noticed some fatal problems: [1] It is impossible to share CONFIG options across the images. If you change the configuration of Main image, you often have to adjust some SPL configurations correspondingly. Currently, we cannot handle the dependencies between them. It means one of the biggest advantages of Kconfig is lost. [2] It is too painful to change both ".config" and "spl/.config". Sunxi guys started to work around this problem by creating a new configuration target. Commit cbdd9a9737cc (sunxi: kconfig: Add %_felconfig rule to enable FEL build of sunxi platforms.) added "make *_felconfig" to enable CONFIG_SPL_FEL on both images. Changing the configuration of multiple images in one command is a generic demand. The current implementation cannot propose any good solution about this. [3] Kconfig files are getting ugly and difficult to understand. Commit b724bd7d6349 (dm: Kconfig: Move CONFIG_SYS_MALLOC_F_LEN to Kconfig) has sprinkled "if !SPL_BUILD" over the Kconfig files. [4] The build system got more complicated than it should be. To adjust Linux-originated Kconfig to U-Boot, the helper script "scripts/multiconfig.sh" was introduced. Writing a complicated text processor is a shell script sometimes caused problems. Now I believe the "single .config" will serve us better. With it, all the problems above would go away. Instead, we will have to add some CONFIG_SPL_* (and CONFIG_TPL_*) options such as CONFIG_SPL_DM, but we will not have much. Anyway, this is what we do now in scripts/Makefile.spl. I admit my mistake with my apology and this commit switches to the single .config configuration. It is not so difficult to do that: - Remove unnecessary processings from scripts/multiconfig.sh This file will remain for a while to support the current defconfig format. It will be removed after more cleanups are done. - Adjust some makefiles and Kconfigs - Add some entries to include/config_uncmd_spl.h and the new file scripts/Makefile.uncmd_spl. Some CONFIG options that are not supported on SPL must be disabled because one .config is shared between SPL and U-Boot proper going forward. I know this is not a beautiful solution and I think we can do better, but let's see how much we will have to describe them. - update doc/README.kconfig More cleaning up patches will follow this. Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com> Reviewed-by: Simon Glass <sjg@chromium.org>
2015-02-24 13:26:20 +00:00
if SPL
config SPL_NAND_DENALI
bool "Support Denali NAND controller for SPL"
help
This is a small implementation of the Denali NAND controller
for use on SPL.
endif
endmenu