On Tue, Dec 06, 2016 at 02:48:27PM +0100, Fabien Parent wrote:
Moving to CONFIG_SPL_*_LOAD options to Kconfig offers several advantage:
- simpler config headers
- on some boards we can easily switch to another boot media without needing to modify the config headers.
This series fixes an issue in davinci where a wrong option was used in place of a CONFIG_SPL_*_LOAD option, then move the options to Kconfig options, and finally start using these Kconfig options for the OMAPL138-LCDK board.
Fabien Parent (3): davinci: spl: use correct macro to select boot device SPL: create Kconfig options for CONFIG_SPL_*_LOAD davinci: omapl138_lcdk: use new CONFIG_SPL_*_LOAD Kconfig options
arch/arm/mach-davinci/spl.c | 2 +- common/spl/Kconfig | 25 +++++++++++++++++++++++++ configs/omapl138_lcdk_defconfig | 1 + include/configs/omapl138_lcdk.h | 2 -- scripts/config_whitelist.txt | 3 --- 5 files changed, 27 insertions(+), 6 deletions(-)
So, I think this shows that some of the SPL framework needs to be revisited for davinci. First, lets make it clear what CONFIG_SPL_{SPI,NAND,MMC}_LOAD is doing.
CONFIG_SPL_MMC_LOAD is used to flag that on davinci we're loading U-Boot from MMC. It's not set / used today but I assume it was working when I introduced all of this.
CONFIG_SPL_NAND_LOAD is used for two things. First, it is used to flag that on davinci we're loading U-Boot from NAND. Second, it is used to enable the non-SPL_FRAMEWORK NAND driver (drivers/mtd/nand/nand_spl_load.c). This driver is not used on davinci.
CONFIG_SPL_SPI_LOAD is used for two things. First, it is used to flag that on davinci we're loading U-Boot from SPI flash. Second, it used globally to enable common/spl/spl_spi.c.
NAND boot is done here via CONFIG_SPL_NAND_SIMPLE which is the regular SPL framework based NAND driver (drivers/mtd/nand/nand_spl_simple.c). This also means that the patch to update CONFIG_SYS_NAND_U_BOOT_SIZE was not needed since we don't use that driver.
Now, I think that in retrospect arch/arm/mach-davinci/spl.c::spl_boot_device could be re-worked to key off of CONFIG_SPL_NAND_SIMPLE / CONFIG_SPL_SPI_SUPPORT / SPL_MMC_SUPPORT.
And a good but possibly complex series would be to consolidate the usage of SPL_SPI_SUPPORT, SPL_SPI_FLASH_SUPPORT and SPL_SPI_LOAD just in to SPL_SPI_SUPPORT. I'll probably try and do this myself as there's a ton of build testing and size checking to make sure nothing odd breaks here to do.