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* Avoid two step navigation to get to the description of the write command. * Add missing index entries * Correct formatting of the examples. * Describe configuration and return value. Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
50 lines
1.2 KiB
ReStructuredText
50 lines
1.2 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0-or-later
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.. index::
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single: read (command)
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read command
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============
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Synopsis
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--------
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::
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read <interface> <dev[:part|#partname]> <addr> <blk#> <cnt>
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Description
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-----------
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The read command can be used for raw reading data from a block device
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(or a partition therein), i.e. without going through a file system.
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The block device is specified using the <interface> (e.g. "mmc") and
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<dev> parameters. If the block device has a partition table, one can
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optionally specify a partition number (using the :part syntax) or
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partition name (using the #partname syntax). The command then reads
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the <cnt> blocks of data starting at block number <blk#> of the given
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device/partition to the memory address <addr>.
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Examples
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--------
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.. code-block:: bash
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# Read 2 MiB from partition 3 of mmc device 2 to $loadaddr
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read mmc 2.3 $loadaddr 0 0x1000
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# Read 16 MiB from the partition named 'kernel' of mmc device 1 to $loadaddr
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read mmc 1#kernel $loadaddr 0 0x8000
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Configuration
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-------------
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The read command is only available if CONFIG_CMD_READ=y.
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Return value
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------------
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The command sets the return value $? to 0 (true) on success or to 1 (false) in
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case of an error.
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