uboot commad test test - minimal test like /bin/sh so we can use test command to some judge for example, test –n $uenvcmd    test var uenvcmd length !eq  zero detail learning you  can reference url: https://www.cnblogs.com/tankblog/p/6160808.html Not…

reference: http://www.denx.de/wiki/DULG/UBootCmdGroupExec => help source source - run script from memory Usage: source [addr] - run script starting at addr - A valid image header must be present => With the source command you can run "shell&quo…

=> fstypefstype - Look up a filesystem type Usage:fstype <interface> <dev>:<part>- print filesystem typefstype <interface> <dev>:<part> <varname>- set environment variable to filesystem type example: => fsty…

=> part --helppart - disk partition related commands Usage:part uuid <interface> <dev>:<part> - print partition UUIDpart uuid <interface> <dev>:<part> <varname> - set environment variable to partition UUIDpart…

我使用的U-Boot版本是u-boot-2012.10,编译的步骤为 cd u-boot-2012.10 make s5p_goni_config sudo make 然后,就会看到错误提示 /bin/bash: arm-linux-gcc: command not found dirname: missing operand Try 'dirname --help' for more information. 在arm-linux-gcc确认安装无误的前提下(可以参照 https://www.…

pseudocode: If(reset_button was pressed ) { Change  uboot env bootslot^1 }…

design: when uboot load kerne failed,we can switch to stanbdy system; how to realize: when boot fail, we can let uboot env bootKenrelFailCount++, then save to uboot_env partiton.    watchdog timeout will trigger cpu reset, when bootKernelFailCount bi…

find cpu datasheet , watchdog relate registers: 0x18060008 watchdong timer control 0x1806000c watchdog timer we can read and write watchdog register under uboot console: #mw 0x1806000c 0xffffffff  1 #mw 0x1806000c 0x10000000  1 #mw 0x18060008    0x3 …

reference :https://github.com/lentinj/u-boot/blob/master/doc/README.autoboot how to enable protect sonsole in uboot stage ? we can add follow contest in include/configs/xxxx.h +// add by panzidong for support  protect uboot console +#define CONFIG_AU…

reference: uboot_dir/doc/README.distro Linux distributions are faced with supporting a variety of boot mechanisms,environments or bootloaders (PC BIOS, EFI, U-Boot, Barebox, ...). This makeslife complicated. Worse, bootloaders such as U-Boot have a c…