| .. SPDX-License-Identifier: GPL-2.0-or-later | |
| .. index:: | |
| single: read (command) | |
| read command | |
| ============ | |
| Synopsis | |
| -------- | |
| :: | |
| read <interface> <dev[:part|#partname]> <addr> <blk#> <cnt> | |
| Description | |
| ----------- | |
| The read command can be used for raw reading data from a block device | |
| (or a partition therein), i.e. without going through a file system. | |
| The block device is specified using the <interface> (e.g. "mmc") and | |
| <dev> parameters. If the block device has a partition table, one can | |
| optionally specify a partition number (using the :part syntax) or | |
| partition name (using the #partname syntax). The command then reads | |
| the <cnt> blocks of data starting at block number <blk#> of the given | |
| device/partition to the memory address <addr>. | |
| Examples | |
| -------- | |
| .. code-block:: bash | |
| # Read 2 MiB from partition 3 of mmc device 2 to $loadaddr | |
| read mmc 2.3 $loadaddr 0 0x1000 | |
| # Read 16 MiB from the partition named 'kernel' of mmc device 1 to $loadaddr | |
| read mmc 1#kernel $loadaddr 0 0x8000 | |
| Configuration | |
| ------------- | |
| The read command is only available if CONFIG_CMD_READ=y. | |
| Return value | |
| ------------ | |
| The command sets the return value $? to 0 (true) on success or to 1 (false) in | |
| case of an error. |