U-Boot
From linux-sunxi.org
(Redirected from U-boot)
Initially developed by Tom Cubie and now developed and maintained by Henrik Nordström the u-boot support comes in two branches, one with NAND and android stuff(boot.img, fastboot) support and another with MMC-only (aka SD) support, which is more the traditional linux style.
For details see the linux-sunxi u-boot wiki.
Contents |
MMC Layout
| start | size | usage |
|---|---|---|
| 0 | 8KB | Unused, available for partition table etc. |
| 8 | 24KB | Initial SPL loader |
| 32 | 512KB | u-boot |
| 544 | 128KB | environment |
| 672 | 352KB | reserved |
| 1024 | - | Free for partitions |
Tutorials
How to remove the old environment from a card:
card=/dev/sdc #/dev/mmcblk0
dd if=/dev/zero of=${card} bs=1024 seek=544 count=128
u-boot nand enviroment
Example u-boot enviroment from a stock android u-boot enviroment partition
bootdelay=0
bootcmd=run setargs boot_normal
console=ttyS0,115200
nand_root=/dev/nandc
mmc_root=/dev/mmcblk0p4
init=/initloglevel=8
setargs=setenv bootargs console=${console} root=${nand_root} init=${init} loglevel=${loglevel}
boot_normal=nand read 40007800 boot;boota 40007800
boot_recovery=nand read 40007800 recovery;boota 40007800
boot_fastboot=fastboot
