U-Boot patch to use uEnv.txt instead of boot.scr

Hi,

attached is a patch for U-Boot (should work on 2016.09-rc1 and 2016-09-rc2-dirty, will probably work on older ones as well) that makes it use the plain text file uEnv.txt instead of boot.scr, which has to be translated to a binary file first. This way changing the environment means only editing a text file, instead of editing a file, converting it to binary, and copying it over to the /boot partition on the SD. This becomes active if the U-Boot config has the option OLD_SUNXI_COMPAT disabled (in the menuconfig this is under ARM architecture -> Enable workarounds for booting old kernels).

It also adds a small patch to board/sunxi/board.c to skip the setting of the MAC address if the option CONFIG_CMD_NET is disabled. That way it is possible to leave out networking stuff and save some time at boot because it doesn't init the networking stuff. Personally i prefer a boot that is as quick as possible, because i just hate it to wait for no useful reason On my board it basically just falls through to immediately boot the kernel after power-up, because i have the wait time for user-input disabled as well in the config.

As an example, this is what my uEnv.txt looks like, i have reserved a core and incresed the loglevel:

machid=1029
bootm_boot_mode=sec
bootargs=console=ttyS0,115200 noinitrd root=/dev/mmcblk0p2 rootfstype=ext4 rootwait loglevel=7 isolcpus=3
bootcmd=load mmc 0 0x43000000 script.bin; load mmc 0 0x40008000 uImage; bootm 0x40008000

Greetings,

Chris

0000-use-uEnv.txt-by-default-on-sunxi.patch.gz