doc/usage/cmd/fatload.rst

.. SPDX-License-Identifier: GPL-2.0+:

.. index::
   single: fatload (command)

fatload command
===============

Synopsis
--------

::

    fatload <interface> [<dev[:part]> [<addr> [<filename> [bytes [pos]]]]]

Description
-----------

The fatload command is used to read a file from a FAT filesystem into memory.
You can always use the :doc:`load command <load>` instead.

The number of transferred bytes is saved in the environment variable filesize.
The load address is saved in the environment variable fileaddr.

interface
    interface for accessing the block device (mmc, sata, scsi, usb, ....)

dev
    device number

part
    partition number, defaults to 0 (whole device)

addr
    load address, defaults to environment variable loadaddr or if loadaddr is
    not set to configuration variable CONFIG_SYS_LOAD_ADDR

filename
    path to file, defaults to environment variable bootfile

bytes
    maximum number of bytes to load

pos
    number of bytes to skip

addr, bytes, pos are hexadecimal numbers.

If either 'pos' or 'bytes' are not aligned according to the minimum alignment
requirement for DMA transfer (ARCH_DMA_MINALIGN) additional buffering will be
used, a misaligned buffer warning will be printed, and performance will suffer
for the load.

Example
-------

::

    => fatload mmc 0:1 ${kernel_addr_r} snp.efi
    149280 bytes read in 11 ms (12.9 MiB/s)
    =>
    => fatload mmc 0:1 ${kernel_addr_r} snp.efi 1000000
    149280 bytes read in 9 ms (15.8 MiB/s)
    =>
    => fatload mmc 0:1 ${kernel_addr_r} snp.efi 1000000 100
    149024 bytes read in 10 ms (14.2 MiB/s)
    =>
    => fatload mmc 0:1 ${kernel_addr_r} snp.efi 10
    16 bytes read in 1 ms (15.6 KiB/s)
    =>

Configuration
-------------

The fatload command is only available if CONFIG_CMD_FAT=y.

Return value
------------

The return value $? is set to 0 (true) if the file was successfully loaded
even if the number of bytes is less then the specified length.

If an error occurs, the return value $? is set to 1 (false).