| .. SPDX-License-Identifier: GPL-2.0+: | |
| .. index:: | |
| single: booti (command) | |
| booti command | |
| ============= | |
| Synopsis | |
| -------- | |
| :: | |
| booti [<addr> [<initrd>[:<size>]] [<fdt>]] | |
| Description | |
| ----------- | |
| The booti command is used to boot a Linux kernel in flat or compressed | |
| 'Image' format. Which compressed formats are supported is configurable. | |
| addr | |
| address of kernel image, defaults to CONFIG_SYS_LOAD_ADDR. | |
| initrd | |
| address of the initial RAM disk. Use '-' to boot a kernel with a device | |
| tree but without an initial RAM disk. | |
| size | |
| size of the initial RAM disk. This parameter must be specified for raw | |
| initial RAM disks. | |
| fdt | |
| address of the device tree. | |
| To support compressed Image files the following environment variables must be | |
| set: | |
| kernel_comp_addr_r | |
| start of memory area used for decompression | |
| kernel_comp_size | |
| size of the compressed file. The value has to be at least the size of | |
| loaded image for decompression to succeed. For the booti command the | |
| maximum decompressed size is 10 times this value. | |
| Example | |
| ------- | |
| This is the boot log of an Odroid C2 board: | |
| :: | |
| => load mmc 0:1 $fdt_addr_r dtb-5.10.0-3-arm64 | |
| 27530 bytes read in 7 ms (3.7 MiB/s) | |
| => load mmc 0:1 $kernel_addr_r vmlinuz-5.10.0-3-arm64 | |
| 26990448 bytes read in 1175 ms (21.9 MiB/s) | |
| => load mmc 0:1 $ramdisk_addr_r initrd.img-5.10.0-3-arm64 | |
| 27421776 bytes read in 1209 ms (21.6 MiB/s) | |
| => booti $kernel_addr_r $ramdisk_addr_r:$filesize $fdt_addr_r | |
| Moving Image from 0x8080000 to 0x8200000, end=9c60000 | |
| ## Flattened Device Tree blob at 08008000 | |
| Booting using the fdt blob at 0x8008000 | |
| Loading Ramdisk to 7a52a000, end 7bf50c50 ... OK | |
| Loading Device Tree to 000000007a520000, end 000000007a529b89 ... OK | |
| Starting kernel ... | |
| The kernel can be compressed with gzip: | |
| .. code-block:: bash | |
| cd /boot | |
| gzip -k vmlinuz-5.10.0-3-arm64 | |
| Here is the boot log for the compressed kernel: | |
| :: | |
| => setenv kernel_comp_addr_r 0x50000000 | |
| => setenv kernel_comp_size 0x04000000 | |
| => load mmc 0:1 $fdt_addr_r dtb-5.10.0-3-arm64 | |
| 27530 bytes read in 6 ms (4.4 MiB/s) | |
| => load mmc 0:1 $kernel_addr_r vmlinuz-5.10.0-3-arm64.gz | |
| 9267730 bytes read in 402 ms (22 MiB/s) | |
| => load mmc 0:1 $ramdisk_addr_r initrd.img-5.10.0-3-arm64 | |
| 27421776 bytes read in 1181 ms (22.1 MiB/s) | |
| => booti $kernel_addr_r $ramdisk_addr_r:$filesize $fdt_addr_r | |
| Uncompressing Kernel Image | |
| Moving Image from 0x8080000 to 0x8200000, end=9c60000 | |
| ## Flattened Device Tree blob at 08008000 | |
| Booting using the fdt blob at 0x8008000 | |
| Loading Ramdisk to 7a52a000, end 7bf50c50 ... OK | |
| Loading Device Tree to 000000007a520000, end 000000007a529b89 ... OK | |
| Starting kernel ... | |
| Configuration | |
| ------------- | |
| The booti command is only available if CONFIG_CMD_BOOTI=y. | |
| Which compression types are supported depends on: | |
| * CONFIG_BZIP2 | |
| * CONFIG_GZIP | |
| * CONFIG_LZ4 | |
| * CONFIG_LZMA | |
| * CONFIG_LZO | |
| * CONFIG_ZSTD | |
| Return value | |
| ------------ | |
| Normally this command does not return. If an error occurs, the return value $? | |
| is set to 1 (false). If the operating system returns to U-Boot, the system is | |
| reset. |