What is U-Boot command line?

What is U-Boot command line?

Das U-Boot (“the Universal Boot Loader” or U-Boot) is an open-source bootloader that can be used on ST boards to initialize the platform and load the Linux® kernel.

How do I get to U-Boot from command prompt?

Booting into U-Boot

1. Log in to your switch via the console.
2. Reboot the switch: cumulus@switch~:$ sudo reboot.
3. Press any key when you see the following prompt: Hit any key to stop autoboot: 0 The full output from the boot sequence is in this file: reboot.txt.
4. The switch will now boot into U-Boot.

How do I turn off U-Boot?

3.4 The boot process To stop the automatic booting (autoboot) of the pre-installed kernel, send a character to the serial port by pressing a key from the serial console connected to the target. If U-Boot is stopped, it displays a command line console (also called monitor).

What is U-Boot used for?

U-Boot runs a command-line interface on a console or a serial port. Using the CLI, users can load and boot a kernel, possibly changing parameters from the default. There are also commands to read device information, read and write flash memory, download files (kernels, boot images, etc.)

How configure U-Boot?

To summarize, you need to configure U-Boot for your with the following steps:

1. Add your board device tree: arch/arm/dts/.
2. Create your own board support directory: board//.
3. Add TARGET_ _ in Kconfig.
4. Create your board defconfig: defconfig/_defconfig.

How do I configure u-boot?

How do I enable debug prints in u-boot?

activate the debug UART feature:

1. add in defconfig of U-Boot configuration. CONFIG_DEBUG_UART. CONFIG_DEBUG_UART_STM32.
2. adpat the function board_debug_uart_init(): that configures the required resources (pad, clock) before initialization by the U-Boot driver. This function needs to be adapted for your board.

What does the U mean in BIOS?

BIOS is essentially a PC concept, having appeared in CP/M personal computers and the original IBM PC. U-Boot tries to live up to its name (“Universal Boot”), and has been ported to many architectures/platforms.

How do you compile U-Boot for arms?

Compile U-Boot

1. Get a toolchain. If you haven’t done so before, get a suitable toolchain installed and added to your PATH.
2. Get the Device-tree Compiler.
3. Clone the repository.
4. Determine build target.
5. Build.
6. Boot.
7. Setting u-boot environment variables.
8. NAND.

What is Bootargs in U-Boot?

When combined with a U-Boot variable named bootargs, this feature allows you to tell the kernel how to configure various device drivers, where to find the root filesystem and can even be used to pass information to applications on the system. …