Igor, > On 19 Feb 2017, at 12:52, Igor Grinberg <grinb...@compulab.co.il> wrote: > > On 02/17/17 19:28, Philipp Tomsich wrote: >> This introduces the ability to override the environment offets from the >> device tree by setting the following nodes in '/config': >> 'u-boot,mmc-env-offset' - overrides CONFIG_ENV_OFFSET >> 'u-boot,mmc-env-offset-redundant' >> - overrides CONFIG_ENV_OFFSET_REDUND >> >> To keep with the previous logic, the CONFIG_* defines still need to >> be available and the statically defined values become the defaults, >> when the corresponding properties are not set in the device-tree. > > That sounds too odd... > DT's purpose is to describe the h/w... and that does not look so... > We also, have a dt file name in the environment, so this creates will create > a chicken and an egg problem…
I don’t really follow… as far as I knew the DT name would have to come from some other source anyway, as the device containing the env might only be described through the device tree (e.g. mmc0). U-Boot usually locates the FDT to use at a preconfigured address (or one configured in the early environment). This will not be the environment we’d load from a MMC device configured via DM_MMC. So there shouldn’t be a chicken & egg here. > I really don't think we should go that direction. DT is not meant to provide > a solution to all your problems... I don’t see how this is different from other entries in chosen and config as of today: common/autoboot.c allows an override through /config/bootdelay common/board_r.c uses /config/load-environment common/cli.c can pull in /config/bootcmd drivers/serial/serial-uclass.c uses /chosen/stdout-path In fact, it is the absence of this mechanism that is causing problems today: CONFIG_ENV_OFFSET is not configurable through Kconfig, so we would need board-specific defines (e.g. CONFIG_SUNXI_BOARD_LYNX) and matching #ifdef primitives in a shared header (sunxi-common.h in our case). So putting this in the DT is the best (and least intrusive) option available. Regards, Philipp. _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot